Distribution and accumulation of biogenic silica in the intertidal sediments of the Yangtze Est

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应用流式细胞术测定淡水、海洋沉积物中异养细菌前处理条件的选择

2008年第3卷生态毒理学报Vol.3, 2008第3期, 307−312Asian Journal of Ecotoxicology No.3, 307−312应用流式细胞术测定淡水、海洋沉积物中异养细菌前处理条件的选择季倩，张经*华东师范大学河口海岸学国家重点实验室，上海 200062摘要：目前流式细胞术(FCM)已被广泛应用于水体异养细菌的检测，采用适当的前处理方法可将黏附在沉积物颗粒上的异养细菌提取到水相中进而利用FCM进行检测. 选择合适的前处理方法是将FCM应用于沉积物异养细菌检测的关键.论文对FCM测定沉积物中异养细菌的前处理方法进行了探讨，实验同步考虑了淡水及海洋沉积物. 结果表明，对于实验所用淡水、海洋沉积物，较优的前处理条件为：1mmol·L−1焦磷酸钠作为分散剂，暗处孵育10min，20w、40KHz水浴超声1min，并每30s人工振荡1次，2800r·min−1常温离心萃取3次.关键词：流式细胞术；异养细菌；沉积物；前处理文章编号：1673-5897(2008)3-307-06 中图分类号：Q93，X172文献标识码：AOptimization in Pretreatment Conditions for Determination of Heterotrophic Bacteria from Freshwater and Marine Sediments Using Flow CytometryJI Qian, ZHANG Jing*State Key Laboratory of Estuarine and Coastal Research, East China Normal University, Shanghai 200062Received12 March 2008 accepted 6 May 2008Abstract:The Flow Cytometry (FCM) has been widely used to determine the heterotrophic bacteria in water environment presently. Also, it can be used to determine the heterotrophic bacteria in benthos environment after the appropriate pretreatment. The treatmentof extracting sediment-attached bacteria to water environment is the key point of applying the FCM to the study of benthos. This paper discussed the methods of pretreatment for the FCM to detect the heterotrophic bacteria both in freshwater and marine sediments. Results showed that the relatively preferable pretreatment conditions for sediments were: sodium pyrophosphate as the dispersant with the final concentration of 1mmol·L−1 and incubated 10min in dark; sonicate 1min in water bath at 20w, 40KHz power with a manual shake every 30s; and centrifugal extraction 3 times with 2800 r·min−1 at room temperature.Keywords: flow cytometry; heterotrophic bacteria; sediment; pretreatment收稿日期:2008-03-12 录用日期: 2008-05-06基金项目: 教育部“创新团队”项目(No. PCSIRT0427)；国家自然科学基金项目(No. 40476036)作者简介: 季倩(1982—)，女，硕士研究生，E-mail: jiqian22@；*通讯作者(Corresponding author)，E-mail: jzhang@sklec.308 生态毒理学报第3卷1引言(Introduction)流式细胞术(Flow cytometry)以其样品制备简单、可进行快速多参数数据采集、测定精确、不易受溶解有机物的干扰等优越性而成为水生和环境微生物学研究的重要工具(潘洛安等，2005). 上世纪80年代后，FCM被应用于海洋科学研究中，主要用于检测海水环境中的微型、微微型浮游生物，并已建立起一套相对完善的检测方法. 近年来，利用FCM 检测水体中异养细菌也屡有报道(焦念志等，1999；潘洛安等，2005). 异养细菌既是分解者又是生产者，底栖环境包括海洋沉积物、陆地土壤等均含有大量的异养细菌. 有毒物质在沉积物中的转化主要受到生物降解作用的影响，而底栖环境中异养细菌对生物降解、生态系统能量的传递等均具有十分重要的作用(张志南等，2003). 准确检测沉积物中的异养细菌是研究海洋沉积物生态毒理学、生物地球化学循环的重要前提之一.关于沉积物中异养细菌的检测，最开始采用直接培养法或荧光镜检的方法来计算其丰度(赵昌会等，2006；Dumahel et al., 2006；赵海萍等，2007)，过程繁琐，误差较大. 而FCM主要针对液相样品，因此对沉积物中异养细菌的检测存在一定的限制，需要将沉积物中的异养细菌转移到溶液中，而后根据已有的测定水样中异养细菌的方法进行检测. 为了有效地提取沉积物中的异养细菌，首先需要将沉积物和异养细菌分离. 目前，文献中提到的方法主要有添加分散剂、超声、离心萃取等(Maranger et al., 1996；Danovaro et al., 2001；2002；Dumahel et al., 2006). Danovaron等(2001；2002)讨论了FCM测定沉积物中的病毒的前处理方法，但是否可用于异养细菌的检测并没有详细分析；Dumahel等(2006)对FCM测定沉积物中的异养细菌进行了讨论，但其主要针对湖水沉积物，同时没有对磷酸盐分散剂种类及终浓度和孵育时间进行讨论. 国内关于利用FCM 检测沉积物异养细菌的前处理方法则未见报道. 本文以淡水、海洋沉积物为研究对象，对利用FCM测定沉积物中异养细菌的前处理条件进行了选择，初步确定了分散剂的种类、浓度、超声时间、萃取次数等，以期最大程度地将沉积物中的异养细菌萃取到上层液相样品中，从而运用FCM进行染色测定. 2 材料与方法(Materials and methods)2.1 沉积物样本实验中，海洋、淡水表层沉积物样品分别取自东海大陆架(125.01°E，28.27°N)及长江下游的徐六泾(121.03°E，31.77°N)，徐六泾沉积物样品由抓斗取得，东海大陆架沉积物样品由箱式采样器取得. 在实验中，为减少取样误差，先将沉积物样品搅拌均匀，后各取0.5mL沉积物作为平行分样，加入经0.02μm滤膜过滤的1%多聚甲醛4mL固定后，漩涡混合器振荡3min，暗处保存.2.2 主要的实验仪器及试剂FACScan型流式细胞仪(Becton Dickinson公司，美国)，SYBR Green I染料(SYBR-I，Molecular Probes 公司，美国)，0.02μm滤膜(Whatman公司，美国)，1.002μm荧光微球(Polysciences公司，美国)，微量移液枪，焦磷酸钠(Na4P2O7·10H2O，AR级)，六偏磷酸钠((NaPO3)6，CP级)，漩涡混合器，SCSF-1B 超声波仪，LXJ-II型离心沉淀机，高压灭菌锅. 实验中用新鲜制备的Milli-Q水配制所需试剂，并在0.1MPa、120℃条件下高压灭菌. 测定结果用Cell-Quest TM软件统计分析，t-检验用SPSS统计软件进行.2.3 实验方法参考文献报道数据，假定实验条件，然后对某一前处理条件进行优化选择. 考虑沉积物中异养细菌的可检测数量及相关的FCM分析的信号清晰程度，选择最优的前处理条件，以利于FCM的检测分析. 具体的假定实验条件见表1，所选择的前处理条件见表2.表1FCM测定沉积物中异养细菌实验的假定前处理条件Table 1 The assumed pretreatment conditions to detect the heterotrophic bacteria in the sediments using FCM假定实验条件沉积物0.5mL分散剂焦磷酸钠分散剂终浓度5mmol·L−1孵育时间10min超声时间1)3min离心萃取次数2)3次注：1): 采用SCSF-1B超声波仪(20w、40KHz)；2): 采用LXJ-II型离心沉淀机(650w、50Hz、2800r·min−1)第3期季倩等: 应用流式细胞术测定淡水、海洋沉积物中异养细菌前处理条件的选择309表2FCM测定沉积物中异养细菌实验所选择的前处理条件Table 2 The pretreatment conditions to detect theheterotrophic bacteria in the sediments using FCM所选择的实验条件分散剂焦磷酸钠、六偏磷酸钠分散剂终浓度0、1、2、3、4、5、10mmol·L−1孵育时间0、5、10、15、20min超声时间1)0、1、3、5、10、15min离心萃取次数2)1、2、3次注：1): 采用SCSF-1B超声波仪(20w、40KHz)；2): 采用LXJ-II型离心沉淀机(650w、50Hz、2800r·min−1)由于各个前处理条件的选择并不是一次完成，因此各次实验所用的沉积物可能略有不同，不同批次实验沉积物中的异养细菌数量可能会有一定变动.3结果与分析(Results and analysis)3.1 分散剂水体异养细菌常呈个体分散状态，但也可以因为水团扰动及细菌本身的生活习性而黏附在动植物排泄物和碎屑上(Tuner, 2002；Spiglazov et al., 2004)，集聚成菌团(Aggregates)(国家海洋局，1975)，从而沉降到水底，进入沉积物环境中. 因而需要添加分散剂或表面活性剂，使块状、粘状的沉积物分散为单个个体，解聚菌团，有利于微生物细胞与沉积物颗粒分离(徐永健等，2004).通常采用磷酸盐的缓冲液作为沉积物的分散剂，最常用的是六偏磷酸钠(Sodium hexameta- phosphate)，如在沉积物粒度分析、海洋地质调查中，均将六偏磷酸钠作为分散剂(国家海洋局，1975；孙有斌等，2001)，而在海洋底栖微生物的研究中，则常采用焦磷酸钠(Sodium pyrophosphate)作为分散剂(Bakken et al., 1985；Danovaro et al., 2001；Duhamel et al., 2006). 本实验选择焦磷酸钠和六偏磷酸钠进行对比研究，确定分散剂的终浓度、孵育时间、超声、离心萃取等前处理条件.3.1.1 分散剂终浓度Maranger等(1996)和Danovaro等(2001)指出，焦磷酸钠等分散剂终浓度越高，对微生物的检测噪音越大，因此需要选取最适宜的分散剂浓度. 图1为淡水沉积物、海洋沉积物添加不同浓度分散剂后异养细菌的测定结果. 对于淡水沉积物样品，选择焦磷酸钠所提取的异养细菌略高于六偏磷酸钠，但各浓度下差异不显著(p>0.01). 而对于海洋沉积物选择交磷酸钠所提取的异养细菌则远高于六偏磷酸钠，添加焦磷酸钠更有利于异养细菌的检测，这与Danovaro等(2001)、Duhamel等(2006)的研究结果基本相同. 由图1还可以看出，相比其他浓度，1mmol·L−1焦磷酸钠可以提取更多的异养细菌. 因此综合考虑淡水、海洋沉积物，实验选择焦磷酸钠为分散剂，并选用1mmol·L−1作为终浓度条件. 值得注意的是，对于淡水沉积物样品，添加分散剂后，样品中可检测得的异养细菌数量明显小于未添加分散剂的样品(p<0.01)，可能是由于未添加分散剂的沉图1不同终浓度分散剂对淡水沉积物(a)、海洋沉积物(b)异养细菌测定结果的影响(圆圈表示最终选择的实验条件；异养细菌单位为103·mL−1，以沉积物体积计)Fig.1 The heterotrophic bacterium abundance of freshwater sediment (a) and marine sediment (b) with different finalconcentrations of two dispersants(Circles indicate the selected experimental conditions; unit of bacteria: 103·mL−1, calculated with sediment volumes)310 生态毒理学报第3卷积物样品中，微生物颗粒之间以及非生物颗粒之间的相互粘连，不利于流式细胞仪染色荧光信号的检测，造成信号的重叠或假相增加.3.1.2 分散剂的孵育时间本实验以0~20min为界，讨论分散剂的孵育时间对沉积物中异养细菌的分散效果(图2). 由图2可见，分散剂对淡水及海洋沉积物的作用结果基本一致：随着孵育时间的增加，对异养细菌的提取效率呈先升高后降低趋势，当孵育时间为10min时，可以检测到相对较多的异养细菌. 同时，对于两种沉积物，焦磷酸钠作用效果均优于六偏磷酸钠. 因此，实验选择焦磷酸钠作为分散剂，孵育时间选择10min，以使沉积物获得最好的分散效果.3.2 超声时间通常在PBS缓冲溶液中对沉积物进行超声处理，可使细胞和颗粒进一步分散开，但超声是一种破坏性技术，破碎沉积物的同时也会造成微生物细胞的裂解(Ellery et al., 1984；Boenigk，2004；徐永健等，2004；Foladori et al., 2007)，因此需要选择适中的超声条件. Kepner等(1994)发现在50w条件下超声2.5min可以分离最大数量的吸附微生物，60w、冰浴条件下超声1min分离病毒的效果最好. Maranger和Bird(1996)选择室温超声45s，Danovaro 等(2001，2002)、Duhamel等(2006)则选择室温超声3min. Duhamel等(2006)指出，冰浴超声与室温超声对异养细菌的提取没有很大差别. 本研究根据SCSF-1B超声波仪具体的实验条件，选用20w、40KHz进行实验.超声时间对异养细菌提取的影响如图3所示. 对于淡水沉积物，不同超声时间下，选择焦磷酸钠所提取得异养细菌通常低于六偏磷酸钠，但在超声1min时，二者相差不大，同时超声1min时，焦磷酸钠的提取效果达到最佳. 对于海洋沉积物，在各超声时间下，焦磷酸钠提取效率通常高于六偏磷酸钠，且在超声1min时达到最高. 因此，实验在选用焦磷酸钠作为分散剂的前提下，室温下超声1min，每30s人工振荡1次，可以获得最好的分离效果.3.3 离心萃取次数采用LXJ-II型离心沉淀机(650w、50Hz)，2800r·min−1下离心15min可获得上清液. 通过计算每一次萃取得到的异养细菌浓度与各次萃取所得的异养细菌浓度总和的比值，来检测异养细菌的提取效率(Danovaro et al., 2001). 离心萃取次数对异养细菌提取效率的影响如图4所示. 以淡水沉积物为例，第一次离心萃取效率为69.1%，第二次萃取效率为23.5%，第三、第四次萃取效率分别为4.9%、2.5%. 可见萃取3次，基本上可将沉积物中的异养细菌完全提取.综合以上实验结果，同时考虑淡水、海洋沉积物，选择焦磷酸钠作为分散剂，并添加至1mmol·L−1终浓度，暗处孵育10min，室温下120w、40KHz水图2不同孵育时间对淡水沉积物(a)、海洋沉积物(b)异养细菌测定结果的影响(圆圈表示最终选择的实验条件；异养细菌单位为103·mL−1，以沉积物体积计)Fig.2 The heterotrophic bacterium abundance of freshwater sediment (a) and marine sediment (b) with different incubation time (Circles indicate the selected experimental conditions; unit of bacteria: 103·mL−1, calculated with sediment volumes)第3期季倩等: 应用流式细胞术测定淡水、海洋沉积物中异养细菌前处理条件的选择 311图3 不同超声时间对淡水沉积物(a)、海洋沉积物(b)异养细菌测定结果的影响(圆圈表示最终选择的实验条件；异养细菌单位为103·mL −1，以沉积物体积计)Fig.3 The heterotrophic bacterium abundance of freshwater sediment (a) and marine sediment (b) with different sonication time(Circles indicate the selected experimental conditions; unit of bacteria: 103·mL −1, calculated with sediment volumes)图4 离心萃取次数对淡水沉积物(a)、海洋沉积物(b)异养细菌测定结果的影响(异养细菌单位为103·mL −1，以沉积物体积计)Fig.4 The heterotrophic bacterium abundance of freshwater sediment (a) and marine sediment (b) withdifferent times of centrifuge extraction(unit of bacteria: 103·mL −1, calculated with sediment volumes)浴超声1min ，每30s 人工振荡1次，高速离心萃取3次，可获得较高的异养细菌提取效率.通讯作者简介：张经(1957—)，博士，中国科学院院士，华东师范大学教授，主要从事海洋生物地球化学研究.ReferencesBakken L R. 1985. 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Journal of Ocean University of Qingdao, 33: 375−383 (in Chinese)Zhao C H, Ye D Z, Wei W L. 2006. Research on deep-sea microbiology [J]. Microbiology, 33: 142−146 (in Chinese)Zhao H P, Li X Q, Tao J H. 2007. Methods of fluorescence enumeration of marine bacteria and application [J]. Journal of Hebei University of Engineering (Natural Science Edition), 24: 57−60 (in Chinese)中文参考文献国家海洋局. 1975. GB12763 海洋调查规范(第四分册：海洋地质调查)[S]. 北京: 国家海洋局潘洛安，张利华，张经. 2005. 应用流式细胞术测定水体异养细菌[J]. 海洋环境科学，24: 54−58孙有斌，高抒，鹿化煜. 2001. 前处理方法对北黄海沉积物粒度的影响[J]. 海洋与湖沼，32: 665−671徐永健，焦念志，钱鲁闽. 2004. 水体及沉积物中微生物的分离、检测与鉴定[J]. 微生物学通报，31: 151−155张志南，田胜艳. 2003. 异养细菌在海洋生态系统中的作用[J]. 青岛海洋大学学报，33: 375−383赵昌会，叶德赞，魏文铃. 2006. 深海微生物的研究进展[J]. 微生物学通报，33: 142−146赵海萍，李清雪，陶建华. 2007. 海洋细菌荧光显微计数法及其应用[J]. 河北工程大学学报(自然科学版)，24: 57−60 ◆。

小学上册第9次英语第六单元测验卷

小学上册英语第六单元测验卷英语试题一、综合题(本题有100小题，每小题1分，共100分.每小题不选、错误，均不给分)1. A solution that contains more solute than it can normally hold is called a _____ solution.2.Planting _____ (树木) can help combat climate change.3._____ (护林员) protect forests and their ecosystems.4.shoreline) is where land meets water. The ____5. A chemical change is often irreversible, while a physical change is ______.6.What do we call a place where you can see many different kinds of animals?A. ZooB. AquariumC. MuseumD. ParkA7.How many legs does a spider have?A. 6B. 8C. 4D. 108.The playground is ________ (适合孩子们).9.She is learning to ___. (swim)10.My brother is a _____ (学生) who enjoys reading history.11.What do we call the planet we live on?A. MarsB. VenusC. EarthD. JupiterC12.The vegetables in the garden are _______ (花园里的蔬菜_______).13.The __________ is a large body of saltwater that is smaller than an ocean.14.The ______ shares interesting facts about animals.15.The book is _____ (interesting/boring).16.She is a _____ (作家) contributing to literary magazines.17.My dad loves __________ (培养兴趣).18.My _____ (嫂子) is expecting a baby.19.The __________ (绿色空间) is essential for health.20.I love to read ______ (fiction) books.21.What is the name of the bear from the jungle?A. TeddyB. BalooC. PaddingtonD. WinnieB22.How many zeros are in one thousand?A. OneB. TwoC. ThreeD. Four23.What do you call the plant that grows in water?A. TreeB. FlowerC. Aquatic plantD. BushC24.The bear forages for food, preparing for the cold months ahead in the ____.25.I bought a new ______ (玩具车) that can go very fast. I love to race it with my ______ (朋友).26.What is the common term for a young cat?A. PuppyB. KittenC. CubD. CalfB27.I see a _____ on the table. (lamp)28.My pet ___ (小鸟) sings every morning.29.My aunt visits us every ____.30.What do we call the time of year when it gets cooler?A. WinterB. SpringC. SummerD. Autumn31.The painting is ___. (beautiful)32.We should _______ (敬爱) our teachers.33.The _______ can be very delicate.34.What do we call a young dog?A. KittenB. PuppyC. CubD. FoalB35. A _______ (小鸟) builds its nest in the spring.36.The _____ (peach) tree bears sweet fruit.37. A __________ is formed by the slow accumulation of sediment.38.What do we call the study of the human body?A. AnatomyB. PhysiologyC. BiologyD. MedicineA Anatomy39.I have a toy ________ that can walk.40. A goat climbs _______ and rocky hills easily.41.The symbol for tungsten is _____.42.What type of animal is a frog?A. MammalB. ReptileC. AmphibianD. FishC43.She is wearing a beautiful ___. (hat)44.The zebra has black and white _______ (条纹).45.The chemical formula for sodium sulfite is ______.46. A spring can store _______ energy when compressed.47.The fall of the __________ (罗马帝国) marked the beginning of the Middle Ages.48.The chemical symbol for iron is _____.anic chemistry is the study of ______ compounds.50.What is the name of the festival celebrated on the last day of October?A. ChristmasB. HalloweenC. EasterD. Thanksgiving51.My sister is my best _______ who shares everything.52.What do you call the main character in a movie?A. LeadB. Supporting actorC. ExtraD. DirectorA53.What is the shape of a basketball?A. SquareB. TriangleC. OvalD. Round54.The _____ (dog/cat) is barking.55.The capital city of Nicaragua is __________.56.What is the capital of Argentina?A. Buenos AiresB. SantiagoC. LimaD. Montevideo57.My sister is good at ________ (跳舞).58.How many sides does a square have?A. 2B. 3C. 4D. 559.The _____ (willow) tree has long, drooping branches.60.What is the first month of the year?A. FebruaryB. MarchC. JanuaryD. AprilC61.The cake is ___ (delicious/yummy).62. A chemical equation must be balanced to show the conservation of ______.63.I like to write ______ (诗) about nature and my feelings.64.The river is ______ (calm) and clear.65.What do you call the person who studies stars and planets?A. BiologistB. PhysicistC. AstronomerD. GeologistC66.Which animal is known as "man's best friend"?A. CatB. DogC. RabbitD. Fish67.I like to ___ (write) stories.68.The hummingbird is the only bird that can fly ______ (倒退).69.The ________ (植物经济) is vital for trade.70.Cacti store _______ in their stems.71.How many continents are there?A. 5B. 6C. 7D. 872.The __________ was a significant battle during the American Revolutionary War. (萨拉托加战役)73.I have a collection of ________ (硬币) from different years.74.My aunt gives me good ____.75.I enjoy attending events like __________. They allow me to meet new people and learn about various topics. I always leave feeling inspired.76.What is 4 x 4?A. 12B. 14C. 16D. 18C77.What do we call the study of the distribution and movement of populations?A. DemographyB. SociologyC. AnthropologyD. GeographyA78.The __________ (社区服务) improves quality of life.79.My teacher gives us __________. (作业)80.The river is ___. (flowing)81.The reaction of an acid with a metal produces ______ gas.82.Did you know that a _______ (小海马) changes color?83.My uncle is a fantastic __________ (老师).84.The teacher is _____ (kind/strict) to us.85._____ (阳光) is essential for plants to make their food.86.Certain plants can ______ (提供) shade and cooling.87.The __________ (历史的交织) illustrates unity.88. A wave can travel through solids, liquids, and ______.89.What do we call the person who studies space?A. AstronomerB. AstrologerC. MeteorologistD. PhysicistA Astronomer90.I like to ______ (参与) in environmental campaigns.91. A ______ is a type of rodent that loves to run.92.He is a _____ (工程师) who designs software.93.The __________ (科学技术发展) shapes the future.94.I see a _____ (fox) in the distance.95. A reaction that is reversible can go in ______ directions.96.I find ________ (心理学) fascinating.97.The _____ (邮局) is nearby.98.How many continents are there in the world?A. FiveB. SevenC. SixD. FourB99.What is 10 4?A. 5B. 6C. 7D. 8B100.What do we call a person who flies an airplane?A. PilotB. EngineerC. DoctorD. Teacher。

癌的分化诱导治疗和分化诱导剂汇总

癌的分化诱导治疗和分化诱导剂作者：闫晓光(A1435)综述周训银1 吴军正2审校一般认为，癌细胞的分化程度较正常低，主要有以下几种观点：⑴癌细胞来源于未能完全分化的正常干细胞的异常分化；⑵癌细胞是已完全分化的正常细胞的反分化形成的；⑶癌变是细胞发育的阻抑，即细胞在早期分化阶段被致癌物转化为低分化、高增殖的癌细胞；而在细胞接近于分化完成时，被致癌物转化为高度分化的、低增殖的癌细胞。

不管癌细胞是来自成熟细胞的反分化，或来自未成熟细胞的异常分化，还是阻抑正常细胞的分化，都可以看作是一种细胞分化的疾病，目前已经有许多把恶性细胞再分化成高分化不(或低)增殖正常细胞的例子：⑴Mckinell等人将蛙肾肿瘤细胞核注入受精的去核卵，结果发现肿瘤细胞核改变了基因的表达，经过正常分化，成长为正常的蝌蚪，及至成年蛙，都没有一点恶性肿瘤的迹象。

⑵Mintz由含特异标志的小黑鼠分离畸胎瘤细胞，直接注入另一种含不同基因标志的小白鼠胚胎，然后将胚胎移植到假孕的寄养母鼠的子宫内，结果胚胎长成了正常鼠。

从上面的实验中可以得出下面的启示：⑴至少有部分癌是由于基因的表达及功能改变所致，而基因的结构并未改变。

如果癌都是由于基因的永久性突变，那么畸胎瘤就不可能再分化为正常细胞。

⑵如果癌细胞可以向正常逆转，就有可能设计出一种治疗癌瘤的药物，促使癌细胞再分化成正常细胞。

很多生成因子或化学物质在体内或体外可促进癌细胞分化而降低肿瘤恶性程度的事实，为发展抗癌治疗开辟了一条新途径──分化诱导治疗[1]。

1 分化诱导疗法特点肿瘤细胞分化诱导疗法的基本特点为不杀伤肿瘤细胞，而诱导肿瘤细胞分化为正常或接近正常细胞，即在一些化学制剂的作用下，有的肿瘤细胞出现类似正常细胞的表型，有的恢复了正常细胞的某些功能，这些制剂被称为分化诱导剂，运用分化诱导剂促进体内肿瘤细胞分化来治疗癌症，被称为分化诱导疗法。

目前国内外文献资料对癌细胞分化的叫法有所不同，如：逆转、表型逆转、逆向转化、正常化、脱癌、去恶性及去恶化等，总之，均表达出肿瘤细胞向正常细胞方向发展。

Phytoremediation

Case study
- A liquid fertilizer was supplied weekly to the plants - grow time 4 weeks - Adding selected soil amendments - Plants were harvested 1 week after adding amendments - Shoots were washed - Were dried in an oven at 70°C - Analyzed for U by ICP-AES
Case study
Desorption to soil solution
200 fold increase from 1.2 to 240 mg pH was reduced by 0.5 to 1 unit
Case study
Case study
Case study: Results
- B. juncea is the best plant to accumulate U -Citric acid is the best acid to increase the U uptake of plants -U accumulation is associated with a stronger Pb accumulation -Even in one species there are differences in U uptake -For remediation, the soil has to be washed first with acid to desorp from soil particles - Hyperaccumulation is rapid

名词解释

1、生物药剂学(biopharmaceutics,biophamacy)研究药物及其剂型在体内的吸收、分布、代谢、排泄的过程，阐明药物的剂型因素、机体生物因素和药物疗效之间相互关系的科学。

2、吸收(absorption)药物从用药部位进入体循环的过程。

3、药物的吸收(absorption of drug)药物从用药部位进入体循环的过程。

4、分布(distribution)药物进入体循环后向各组织、器官或者体液转运的过程。

5、代谢(metabolism)药物在吸收过程或进入体循环后，受肠道菌丛或体内酶系统的作用，结构发生转变的过程。

6、生物转化(biotranformation)又称代谢。

同上7、排泄(excretion)药物或其代谢产物排出体外的过程。

8、药物转运(transport)药物吸收、分布、排泄过程的统称。

9、处置(disposition)药物分布、代谢、排泄的过程。

10、消除(elimination)代谢和排泄过程药物被清除，合成消除。

11、膜转运(membrane transport)物质通过生物膜的现象。

12、被动转运(passive transport)指药物的膜转运服从浓度梯度扩散原理，即从高浓度一侧向低浓度一侧扩散的过程。

13、膜孔转运(pore transport)药物通过含水小孔转运的过程。

14、载体媒介转运(carrier-mediated transport)借助生物膜上载体蛋白的作用，使药物透过生物膜而被吸收的过程称为载体媒介蛋白15、促进扩散/易化扩散(facilitated diffusion)指某些物质在细胞膜载体的帮助下，由膜高浓度侧向低浓度侧扩散的过程。

16、主动转运(active transport)借助载体或酶促系统的作用，药物从低浓度侧向高浓度侧的转运过程。

17、膜动转运(membrane mobile transport)通过细胞膜的主动变形将药物摄入细胞内或者从细胞内释放到细胞外的转运过程。

木糖葡萄球菌与金黄色葡萄球菌、表面葡萄球菌的基因组比较(阐述毒力、侵染性,样本是健康人的鼻腔)副本

LETTER TO THE EDITORGenome of Staphylococcus xylosus and Comparison with S.aureusand S.epidermidisStaphylococci are Gram-positive,AT-rich cocci,and often stick together in grape-like clusters.The genus can be classi-ﬁed into two groups based on their ability to produce coagu-lase,an enzyme that causes clotting of blood plasma (Otto,2004).Coagulase-positive Staphylococci include Staphylo-coccus aureus ,a common pathogen of community-acquired and nosocomial infections (Smith et al.,2009).Their inva-siveness is associated with the ability to adhere to host sur-faces (Vuong et al.,2003).Among coagulase-negative Staphylococci (CNS),S.epidermidis is the most frequently found pathogen in humans,and is also a common cause of nosocomial infections (Nostro et al.,2007;Wang et al.,2009).S.epidermidis is believed to account for most of the infections caused by CNS and is highly resistant to many antibiotics including penicillins and cephalosporins (Al-Shuneigat et al.,2005).S.xylosus is also a CNS.It is naturally present in raw meat and milk and is commonly used in starter culture for fermentation (Planchon et al.,2006,2007).This species is normally regarded as non-pathogenic,but a few strains are related to human opportunistic infections (Akhaddar et al.,2010).In addition,some S.xylosus strains have the ability to form bioﬁlm (Planchon et al.,2006).Bacterial virulence genes can be regulated by diffusible signal molecules termed autoinducers (AIs).Because the control of gene expression by AIs is cell-density dependent,this phenomenon has been called quorum sensing (Brelles-Marino and Bedmar,2001;Antunes et al.,2010).In Staphy-lococci,there are two quorum sensing systems,P2and P3.Their regulatory mechanism was described earlier by Liu et al.(2012).Other regulatory genes and virulence factors shared by S.epidermidis and S.aureus have also been reported (Frebourg et al.,2000;Gelosia et al.,2001).However,it is still not clear whether these virulence related genes are also present in non-pathogenic S.xylosus genome.In this study,we isolated S.xylosus NJ from a nasal sample of a healthy person at Jiangsu People’s Hospital in China and determined its genome sequence using whole-genome shotgun sequencing strategy with a Hiseq2000(Illumina,CA,USA)sequencer.The project generated a total of w 2739Mbsequences and w 927folds coverage of the genome.The draft genome data were assembled using the Velvet assembly pro-gram.The assembly generated 45contigs with a size of >200bp,22of which were longer than 500bp with the N 50length of 396,400bp.These 45contigs were deposited in GenBank and annotated using Rapid Annotation using Sub-system Technology (RAST)server.In addition,96tandem repeat sequences were found in these contigs.The draft genome contained a chromosome of 2,940,053bp with a 32.40%G þC content.The general features are listed in Table 1.There are 6predicted rRNA genes and 22tRNA genes,and 83.64%nucleotides are predicted to encode proteins.By a combination of coding potential prediction and homology search,2783coding DNA sequences (CDSs)with an average length of 884bp were identiﬁed on the draft genome (Table 1).The 2199CDSs annotated by speciﬁc Clusters of Orthologous Groups (COG)function groups can be classiﬁed into 21COG categories,and 2456CDSs can be annotated into 1221KEGG orthology by KAAS (Moriya et al.,2007).The organization of the genome of S.xylosus NJ was shown in a circular map in Fig.1A.In addition,phylogenetic dendrogram based on a comparison of 16S rRNA sequences for S.xylosus NJ with members of the Staphylococcus was shown in Fig.S1.There is another S.xylosus draft genome,S.xylosus DMB3-Bh1,in GenBank.Therefore,we compared S.xylosus NJ with S.xylosus DMB3-Bh1using BLAST (version 2.2.26).The result showed that there are 2319CDSs in S.xylosus DMB3-Bh1(89.30%)similar to S.xylosus NJ (Fig.S2).The metabolic network of S.xylosus NJ was constructed using the RAST server with the 411subsystems identiﬁed in the genome.There are many carbohydrate subsystem features,including genes involved in organic acids,fermentation,sugar alcohols,di-and oligo-saccharides,central carbohydrates,monosaccharides,and one-carbon metabolisms.Many protein metabolism features are also present,including protein biosynthesis machinery such as the small subunit (SSU)and large subunit (LSU)of the bacterial ribosome.Moreover,we prepared the comparative analysis of this genome with other staphylococcal genomes (S.aureus subsp.aureus N315(S.Available online at ScienceDirectJournal of Genetics and Genomics 41(2014)413e 416JGG1673-8527/$-see front matter Copyright Ó2014,Institute of Genetics and Developmental Biology,Chinese Academy of Sciences,and Genetics Society of China.Published by Elsevier Limited and Science Press.All rights reserved./10.1016/j.jgg.2014.03.007aureus N315)and S.epidermidis ATCC12228).The results showed that there are 404subsystems for S.aureus N315genome and 381subsystems for S.epidermidis ATCC12228genome.A comparative metabolic network analysis showed that D-galacturonate and D-glucuronate utilization subsystem is only present in S.xylosus NJ genome.However,serine-glyoxylate cycle subsystem is absent in S.aureus N315genome.A more detailed comparative analysis of this genome with these two staphylococcal genomes is summarized in Table S1.The genomic organization of S.xylosus NJ was compared with those of S.aureus N315and S.epidermidis ATCC12228(Table 1).There are 1502CDSs (55.20%)in S.xylosus NJ similar to those in S.aureus N315and 1446CDSs (53.14%)similar to those in S.epidermidis ATCC12228.The number of shared genes among S.xylosus NJ,S.aureus N315,and S.epidermidis ATCC12228was shown in Fig.1B.Over 92%of homologous genes were assigned to COG function groups (Fig.S3).In addition,the larger amount of unique proteins is present for S.xylosus NJ with 1145proteins.Meanwhile,unique genes of three strains were assigned to COG function group.The result showed that the numbers of genes related to energy production and conversion,carbohydrate transport and metabolism,and general function in S.xylosus NJ genome are considerably more than other strains (Fig.S4).Compared to S.aureus N315and S.epidermidis ATCC12228genomes,S.xylosus NJ genome possesses some signiﬁcant differences,such as virulence and defense ability,cell wall and capsule constitution,phages,prophages,trans-posable elements and plasmids,and cell regulation and signaling.In virulence and defense category,adhesins have previously been reported as virulence factors by promoting the accumu-lation phase of bioﬁlm (Corrigan et al.,2007;Kim et al.,2010).In consistent with the non-pathogenic property,no adhesin was detected in S.xylosus NJ.In contrast,six adhesins were present in S.epidermidi s ATCC12228and 22in S.aureus N315(Table S2).Another important gene family,staphylococcal enterotoxins (SEs)encodes powerfulsuperantigens that stimulate non-speciﬁc T-cell proliferation (Balaban and Rasooly,2000).However,there was no gene associated with SEs in S.xylosus NJ genome.S.aureus pro-duce a -hemolysin,g -hemolysin,and leukocidin toxins,which function as two component toxins in the disruption and lysis of erythrocytes and leukocytes (Gouaux et al.,1997).Compared with S.aureus N315,there was no gene in the subcategory of toxins and superantigens in S.xylosus NJ.However,S.xylosusTable 1Chromosome features of S.xylosus NJ,S.aureus N315,and S.epidermidis ATCC12228S.xylosus S.aureus S.epidermidisFig.1.The genomic organization of S.xylosus NJ and the comparison with other Staphylococcus .A:Circular representation of the S.xylosus NJ chromosome.GC-skew:sliding window size of 10kb and calculating (G ÀC)/(G þC)in 500bp steps.Circles from outside to inside:1,contigs were arrange in clockwise direction from large to small;2,CDS on forward strand;3,CDS on reverse strand;4,tRNA genes;5,rRNA genes;6,GC-skew (window size of 10kb);and 7,purple indicates C content and yellow indicates G content (step size 500bp).B:Venn diagram for the deduced proteins in S.xylosus NJ,S.aureus N315and S.epidermidis ATCC12228.The total number of all deduced proteins for these three species is 7781.The number of proteins per each chromosome is given.Values were identiﬁed by BLASTCLUST (version 2.2.26)using an identity of >60%,an alignment coverage of >70%and an e -value of 1e-6as cut-off.The number of clusters represents the non-redundant protein coding genes for intersection.The overlapping sections indicate shared numbers of proteins.414Letter to the Editor /Journal of Genetics and Genomics 41(2014)413e 416NJ carried fewer antibiotic-resistance genes.For instance, teicoplanin andﬂuoroquinolones resistance genes were pre-sent in S.xylosus NJ.Meanwhile,multidrug-resistance efﬂux pumps were also present in S.xylosus NJ,which supports a previous observation made by Piddock(2006)that multidrug-resistance efﬂux pumps have roles not only for resistance to antibiotics,but also in bacterial pathogenicity.However, methicillin resistance genes were not found in S.xylosus NJ.In cell wall and capsule category,sialic acid is a bioavail-able carbon and nitrogen source that is abundant on mucosal surfaces and in secretions in the commensal environment (Olson et al.,2013).It has been shown by Almagro-Moreno and Boyd(2009)that several pathogens,including S.aureus N315,could utilize sialic acid as a carbon source,which in turn establish a competitive advantage in heavily sialylated environments such as the human gut.Our data indicate that S. xylosus NJ,but not S.epidermidis ATCC12228,contains genes associated with sialic acid metabolism(Table S3).Most Staphylococci produce types5and8microcapsules,which account for75%of human infections(Lowy,1998).Types5 and8cap genes were not found in S.xylosus NJ(Table S3).In category of phages,prophages,transposable elements and plasmids,Tn552is not detected in the genome of S.xylosus NJ. The staphylococcal pathogenicity islands(SaPIs)encoded one or more staphylococcal superantigens.We identiﬁed17path-ogenicity islands in S.aureus N315.However,no one was detected in S.xylosus NJ(Table S4).Interestingly,in contrast to S.aureus N315and S.epidermidis ATCC12228,ten copies related to phages and prophages were detected in S.xylosus NJ.In category of cell regulation and signaling,S.xylosus NJ showed signiﬁcant differences in bioﬁlm formation and staph-ylococcal accessory gene regulator systems compared to S. aureus N315and S.epidermidis ATCC12228.Besides adhesins absence in S.xylosus NJ,entire ica genes involved in bioﬁlm formation were not found.Although a few bioﬁlm-positive strains do not produce detectable polysaccharide intercellular adhesin(PIA),the mechanism was not due to the absence of the ica operon,but was a result of reduced transcription or trans-lation of ica genes(Zhang et al.,2003).In addition,S.epi-dermidis ATCC12228is non-bioﬁlm-forming strain due to lack of ica operon(Zhang et al.,2003).So,we speculated that S. xylosus NJ may not form bioﬁlm.However,staphylococcal accessory regulator A(SarA),biofunctional autolysin Atl,and RNA polymerase sigma factor SigB were present in S.xylosus NJ(Table S5).Therefore,we speculated that the function of these genes may be not for bioﬁlm formation,but for others such as virulence factor production.In staphylococcal acces-sory gene regulator system,there were13genes in S.aureus N315and8in S.epidermidis ATCC12228,but none in S. xylosus NJ(Table S5).This may explain the great difference among these strains in virulence.One of the important factors contributing to staphylococcal toxin is their peptide-based quorum sensing system,encoded by the accessory gene regu-lator(agr)locus(Balaban et al.,2004;Kiran et al.,2008; Antunes et al.,2010).The agr locus(agr ABCD)and related genes were not detected in S.xylosus NJ.The comparative genomic analysis suggests that S.xylosus NJ may be less virulent.In addition,we found that ElaA protein and prophage Clp protease-like protein were only present in S.xylosus NJ.In summary,the comparative genomic analysis of S.xylo-sus NJ with S.aureus N315and S.epidermidis ATCC12228 showed great difference on genome composition within this genus.Particularly,ica operon and agr operon were absent in S.xylosus NJ.Here,we described the genome analysis of S. xylosus NJ to provide a new genome for Staphylococcus genome database.In addition,we analyzed genes in S.xylosus NJ different from those in S.aureus N315and S.epidermidis ATCC12228.Their differences mainly exist in genes associ-ated with virulence and pathogenicity,such as adhesins, superantigens,resistance to antibiotics,capsular poly-saccharide synthesis enzymes,pathogenicity islands,quorum sensing and bioﬁlm formation.This study can help reveal how commensal S.xylosus strains evolved into invasive strains. ACKNOWLEDGMENTSThis work was supported by the grants from the National Natural Science Foundation of China(Nos.81301475, 31170131and31070312)and Jiangsu Qinglan Project,and the Shaoxing Major Scientiﬁc and Technological Projects(No. 2011A11013).SUPPLEMENTARY DATASupplementary data related to this article can be found at /10.1016/j.jgg.2014.03.007Xiaojuan Tan a,1,Lin Liu b,c,1,Shili Liu d,Dongting Yang a, Yikun Liu c,Shuang Yang c,Aiqun Jia a,*,Nan Qin b,* a School of Environmental and Biological Engineering,Nanjing University ofScience and Technology,Nanjing210094,Chinab State Key Laboratory for Diagnosis and Treatment of Infectious Disease, The First Afﬁliated Hospital,Zhejiang University,Hangzhou310003,Chinac NGS Sequencing Department,Beijing Genomics Institute(BGI),Shenzhen518083,China d Institute of Pathogen Microbiology,School of Medicine,Shandong University,Jinan250012,China*Corresponding authors.Tel/fax:þ86057187236421. E-mail addresses:nqin@(N.Qin);jiaaiqun@(A.Jia)1These authors contributed equally to this work.Received24January2014Revised21March2014Accepted25March2014Available online12April2014 REFERENCESAkhaddar,A.,Elouennass,M.,Naama,O.,Boucetta,M.,2010.Staphylo-coccus xylosus isolated from an otogenic brain abscess in an adolescent.Surg.Infect.(Larchmt)11,559e561.Almagro-Moreno,S.,Boyd,E.F.,2009.Insights into the evolution of sialic acid catabolism among bacteria.BMC Evol.Biol.9,118.415Letter to the Editor/Journal of Genetics and Genomics41(2014)413e416Al-Shuneigat,J.,Cox,S.D.,Markham,J.L.,2005.Effects of a topical essential oil-containing formulation on bioﬁlm-forming coagulase-negative staph-ylococci.Lett.Appl.Microbiol.41,52e55.Antunes,L.C.,Ferreira,R.B.,Buckner,M.M.,Finlay,B.B.,2010.Quorum sensing in bacterial virulence.Microbiology156,2271e2282. 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石油英语词汇M2

石油英语词汇(M2)margianl-ocean basin 边缘洋盆margin capacity 备用容量margin design 边限设计margin for contingencies 发生意外预留量margin line 界限线margin of drill 钻头切削边缘；钻锋圆边margin of lift 升举限度margin of safety 安全系数margin plate bracket 舭肘板margin plate 缘板margin tolerance 公差范围margin 边缘marginal accretion 边缘增生marginal adjustment 边际调整marginal analysis 边际分析marginal arc 边缘弧marginal assimilation 边缘同化marginal aulacogen 边缘坳拉槽marginal bank 边滩marginal barrier 边缘堤marginal basin 边缘盆地marginal capital coefficient 边际资本系数marginal checking 边缘校验marginal contribution 边际效益marginal cost 边际成本marginal crude oil production 边际原油生产marginal data 图例说明marginal deep sea 陆缘深海marginal deep 边渊marginal definition 边缘清晰度marginal deposit 边缘沉积marginal depression 边缘坳陷marginal development 从油田边缘向中间开发marginal distribution 边缘分布marginal efficiency of capital 资本边际效率marginal efficiency 边际效率marginal facies association 边缘相组合marginal facies 边缘相marginal fault 边缘断层marginal field 边际油气田marginal flood 边缘注水marginal fold 边缘褶皱；附加褶皱marginal freight rate 边际运费率marginal geosyncline 陆缘地槽marginal income statement 边际收益表marginal income 边际收益marginal indifference curve 边际无差别曲线marginal investment 边际投资marginal lagoon 边缘泻湖marginal layer 边际油气层marginal market 边际市场marginal offset 边缘断错marginal oil field 边际油田marginal operation 边缘操作marginal output curve 边际产量曲线marginal price 边际价格marginal principle 边际原理marginal probability 边际概率marginal producer 边际生产井marginal production rate 边际产量marginal productivity 边际生产力marginal profit 边际利润marginal prospects 边际矿区marginal ray 边光marginal revenue 边际收入marginal ridge 围脊marginal ring depression 边缘环形坳陷marginal rise 边缘隆起marginal sea 陆缘海marginal sharpness 边缘清晰度marginal spray 边界喷涂marginal stability 临界稳定性marginal strike 边际产量发现井marginal subsidence 边缘沉陷marginal swell 边缘隆起marginal thrust 边缘冲断层marginal time 临界时间marginal trench 边缘海沟marginal type wharf 顺岸码头marginal unconformity 边缘不整合marginal upthrust 边缘上冲断层marginal utility 边际效用marginal value 临界值；边际值marginal well 边际井marginal 边缘的marginal-marine 滨海的marginalia 图廓marginality 边际性marginarium 边缘区Margodoporites 边沟孔粉属maria mare的复数marialite 钠柱石marignacite 铈烧绿石marigraph 验潮计marine 3-D survey 海上三维勘探marine accident 海上事故marine accumulation 海洋堆积marine acoustics 水声学marine airgun 海洋空气枪marine algae 海藻marine anchor 海上锚定物marine animal 海洋动物marine bar 海相砂坝marine basin 海盆marine beach 海滩marine bed 海相层；海床marine bench 海蚀台marine biocycle 海洋生物带marine biology 海洋生物学marine bottom community 海底群落marine bottom sediment 海底沉积物marine cable 海上电缆marine chemistry 海洋化学marine clastics 海上碎屑岩marine clay 海相粘土marine climate 海洋性气候marine conductor 海上钻井导管marine corrosion 海水腐蚀marine crossing 水下穿越marine cycle 海蚀旋回marine cylinder oil 船用汽缸油marine delta plain 海洋三角洲平原marine denudation 海水侵蚀marine deposit 海相沉积marine detector cable 海上检波电缆marine detector 海上检波器marine diesel engine oil 船用柴油机油marine disaster 海难marine drift 海流marine drilling platform 海上钻井平台marine drilling 海上钻井marine ecology 海洋生态学marine energy source 海上震源marine engine 船用发动机marine engineering survey 海洋工程测量marine environment 海洋环境marine erosion 海蚀marine erosional unconformity 海蚀不整合marine erratics 海相漂砾marine evaporite 海相蒸发岩marine exposure test 海洋环境腐蚀试验marine facies 海相marine fouling organism 海洋污着生物marine fouling 海洋污着marine fungi 海生菌类marine gathering line 海上集输管线marine geochemical prospecting 海洋地球化学探矿marine geology 海洋地质学marine geophysics 海洋地球物理学marine gravimeter 海洋重力仪marine gravimetric survey 海洋重力测量marine gravity meter 海洋重力仪marine group 海员marine growth 海生物marine hydrology 海洋水文学marine ingression 海进marine insurance contract 海洋运输保险合同marine invasion 海侵marine law 海上法marine life 海洋生物marine limestone 海相灰岩marine loss 海损marine magnetometer 海洋磁力仪marine magnetometry 海洋磁力测量marine map 海图marine marsh 沿海沼泽marine navigation 海上导航marine offlap 海上退覆marine oil spill 海上漏油marine oil 海洋石油marine onlap 海相上超marine operation 海上作业marine organism 海洋生物marine origin 海成marine petroleum exploitation 海洋石油开采marine pipe-laying 海上铺管marine plain 海蚀平原；海积平原marine platform 海蚀台地；海上平台marine pneumatic seismic source 海洋压缩空气震源marine pollution prevention law 海洋防污染法规marine pollution 海洋污染marine positioning 海洋定位marine processing technique 海上处理技术marine progressive overlap 海侵超覆marine prospecting 海上勘探marine protection 海洋保护marine railway cradle 船排承架marine railway 船排marine reconnaissance 海上普查marine reflection survey 海洋反射测量marine refraction survey 海洋折射测量marine regression 海退marine reptiles 海栖爬行类marine reservoir rock 海相储集岩marine resources 海洋资源marine riser 隔水管marine salina 海边盐沼marine sdeimentation 海洋沉积作用marine sediment 海洋沉积marine seepage 海底油苗marine seismic cable 海洋地震电缆marine seismic crew 海上地震队marine seismic generator 海洋地震信号发生器marine seismic operation 海上地震作业marine seismic source 海上震源marine seismic streamer 海洋地震拖缆marine seismics 海洋地震学marine seismograph 海洋地震仪marine slipway 船排marine source 海上震源marine streamer 海洋拖缆marine structure 海工结构marine succession 海洋生态演替marine swamp 沿海木本沼泽marine swivel 船用旋转接头marine talus 海下岩屑堆积marine tankage 油轮载量marine terminal 海洋油库；海运末站marine time 海洋地质时代marine transgression 海侵marine trap 海相圈闭marine unconformity 海成不整合marine vertical seismic profiling 海洋垂直地震剖面marine white gasoline 船用白汽油marine 海上的；船用的；船舶marine-built 海积的marineline 海底管线mariner's compass 船用罗盘marining 海侵mariposite 铬硅云母mariposition 海洋沉积Marisat 海上卫星通信系统maritime affair 海运事务Maritime Arbitration Commission 海事仲裁委员会maritime climate 海洋性气候maritime distress 海难maritime glacier 海洋性冰川maritime insurance 海上保险maritime law 海洋法maritime peril 海上遇险maritime province 沿海区域Maritime resources 海洋资源maritime sequence 海岸层序maritime territory 领海maritime work 海工；海塘工程maritime 海的mariupolite 淡霞钠长岩mark buoy 标识浮标mark card 标记卡片mark of conformity 合格标志mark off 区分mark out 标出mark pulse 标志脉冲mark reader 标记读出器mark scannng 标记扫描mark sensed card 标记读出卡片mark up pricing 提高标价法mark 标志mark-on 加标mark-up 涨价Markalius 马卡里氏颗石marked check 保付支票marked compound 标记化合物marked depth line 标定深度线marked flask 带刻度烧瓶marked point 觇标点marked prescription bottle 有标记的样品瓶markedness 显著marker beacon 无线电指向标marker bed 标准层marker bouy 标志浮筒marker crude price 基准油价marker crude 标志原油marker formation 标准层marker horizon 标准层marker register 时标寄存器marker spacing 标志间距marker velocity 标准层速度marker 反射标准层marker-and-cell method 标记点和格子法market abroad 海外市场market analysis 市场分析market climate 市场气候market collapse 市场不景气market consultation 市场咨询market control 市场控制market demand factor 市场需求系数market demand stages 市场需求层次market economy 市场经济market environment 市场环境market feedback 市场反馈market for capital goods 生产资料市场market forecast 市场预测market growth rate 市场需求增长速度market intelligence 市场情报market letter 商情报告书market mechanism 市场机制market mentality 市场心态market occupancy 市场占有率market outlet 市场销路market outlook 市场前景market ouvert 公开市场market practice 习惯作法market price 市场价格market readjustment 市场调节market report 市场报告market research 市场调查market risk 市场风险market saturation 市场饱和market segmentation 市场区分market sepculation 市场投机market share 市场占有率market structure 市场结构market study 市场调研market survey 市场调查market value of the share 股票市价market value of the stock 股票市价market value 市价market 市场market-grade screen 市场级筛网market-oriented production 面向市场的生产market-sharing arrangement 市场分配协定market-to-cost method 市价-成本法marketability 变现能力marketable natural gas 商品天然气marketable securities 可售证券marketable value 市场价值marketable 有销路的marketing channel 销售渠道marketing decision variable 销售决策变量marketing expenses 销售费用marketing indicia 推销标识marketing information 销售信息marketing myopia 经营短视者marketing operation 销售业务marketing planning 市场规划marketing strategy simulation 市场策略模拟marketing technique 销售技术marketing 市场学marketing-oriented management 市场导向型管理markfieldite 斜长花斑岩marking compound 涂色剂marking current 信号电流marking ink 划线蓝铅油marking pin 测钎marking point 标志点marking 标志Markite 导电性塑料markka 马克Markov chain 马尔科夫链Markov operator 马尔科夫算子Markov process 马尔科夫过程Markov sequence 马尔科夫序列Markovian decision 马尔科夫决策Markovian variable 马尔科夫变量markovnikite 富萘石油Markovnikov's rule 马尔科夫尼科夫法则marl ball 泥灰球marl biscuit 泥灰饼marl lake 泥灰湖marl shale 泥灰页岩marl slate 易劈泥灰岩marl 泥灰岩marlaceous 泥灰质的marlekor 冰泥钙结核marlin 绳索marline spike 穿钢绳的工具marlite 硬泥灰岩marloesite 橄榄钠长斑岩marlstone 硬泥灰岩marly bituminous shale 泥灰沥青质页岩marly clay 泥灰质粘土marly 泥灰岩的marmolite 白叶蛇纹岩Marmor 马莫阶marmoration 用大理石贴面marmorization 大理岩化marmorosis 大理岩化marosion 海洋侵蚀marosite 云辉等色岩marque 商品型号marquench 分级淬火marriage 密切结合marrow 髓；精华；活力marry the rope 接钢绳MARS 多道存取检索系统MARS 多孔磁阻开关MARS 管理分析报告系统Mars 火星marscoite 花岗辉长混染岩marsh basin 沼泽盆地marsh buggy 沼泽车marsh dragline 沼泽地拉铲挖土机Marsh funnel viscosity 马氏漏斗粘度Marsh funnel 马氏漏斗marsh gas 沼气marsh geophone 沼泽检波器marsh ground 沼泽地marsh lake 沼泽湖marsh land coast 沼泽海岸marsh land 沼泽地区marsh peat 沼泽泥炭marsh pipelaying barge 沼泽地铺管船marsh pipeline 沼泽地管线marsh plant 沼泽植物Marsh viscometer 马氏粘度计marsh 沼泽marshal 整顿；安排；引导；集结marshy terrain 沼泽地带marshy 沼泽的marsupials 有袋类Marsupipollenites 袋粉属mart 商业中心；市场martempering 分级淬火martensite 马氏体martensitic stucture 马氏体组织martingale 弓式接线；弓形拉线Martiniaster 马廷尼星石martinite 响白碧玄岩marundite 珠云刚玉岩MARV 机动重返大气层运载工具marver 乳光玻璃板marworking 形变热处理mAs 毫安秒MAS 金属-氧化铝-硅MAS 金属氧化铝半导体MAS 魔角旋转技术masafuerite 多橄玄武岩mascareignite 植物蛋白石mascon 质量密集masculine 阳性maser 微波激射器mash 压碎masher 磨碎机mask operation 屏蔽操作mask register 时标寄存器mask 罩maskant 保护层masked element 掩蔽元素masked group 掩蔽团masked radical 掩蔽基masking agent 掩蔽剂masking compound 掩蔽化合物masking 掩蔽Maslovichara 马斯洛夫轮藻属mason 泥瓦工masonite 绝缘纤维板masonry 砖石工程；砌体masout 黑油mass absorption coefficient 质量吸收系数mass accumulation 质量累积mass action law 质量作用定律mass action 质量作用mass analyzer 质谱分析器mass attenuation coefficient 质量衰减系数mass balance 质量平衡mass chromatogram 质量色谱图mass chromatography 质量色谱mass coefficient 附加质量系数mass collection 大量采集mass concentration 质量浓度mass conservation law 质量守恒定律mass conservation 质量守恒mass coupling coefficient 质量耦合系数mass data 大量数据mass defect 质量亏损mass density 质量密度mass depletion 质量亏空mass detector 质量检测器mass distribution 质量分布mass energy absorption coefficient 质能吸收系数mass erosion 重力侵蚀mass excess 质量剩余mass extinction 大量灭亡mass flow imbalance alarm 质量流量不平衡报警器mass flow rate sensitive detector 质量流量敏感型检测器mass flow rate 质量流量mass flow 质量流；块体流mass flowmeter 质量流量计mass flux 质量通量mass force 惯性力mass law 质量定律mass load 惯性负荷mass memory 大容量存储器mass metering 测质量mass mortality 大量死亡mass number 质量数mass output 质量流量mass overthrust 推覆大断层mass peak 质量峰mass point 质点mass polymerization 本体聚合法；整体聚合法mass production 大量生产mass rate of production 质量产量mass rate 质量流量mass ratio 质量比mass resolution 质量分辨率mass scale 质量标度mass spectrogram 质谱mass spectrograph 质谱仪mass spectrographic analysis 质谱分析mass spectrography 质谱分析mass spectrometer 质谱仪mass spectrometric analysis 质谱分析mass spectrophotometer 质谱分光光度计mass spectrophotometry 质谱分析mass spectroscope 质谱仪mass spectroscopy 质谱法mass storage 大容量存储器mass thickness 质量厚度mass transfer coefficient 传质系数mass transfer 传质mass velocity 质量速度mass weighted mean value 质量加权平均值mass 质量；块mass-energy equivalence 质能等价性mass-flow deposit 块体流沉积mass-flow gas meter 气体质量流量计mass-gravity transport 块体重力搬运mass-spectrometer tube 质谱仪管mass-spectrometry 质谱学mass-spectrum 质谱mass-synchrometer 同步质谱仪mass-to-charge ratio 质荷比mass-wasting 块体坡移massenfilter 滤质器massicot 氧化铅massif 地块massive conglomeratic reservoir 块状砾岩储集层massive exposure 强照射massive foundation 大块式基础massive hydraulic fracturing 大型水力压裂massive oil pool 块状油藏massive sandstone facies 块状砂岩相massive slump 块状滑动massive 重的massiveness 厚实；块状；非晶质；均匀构造massula 花粉块mast antenna 桅杆式天线mast crane 桅杆起重机mast raising sheave 井架起升滑轮mast support 井架支座mast 柱mast-up 吊装架master budget 总预算master bushing 转盘方瓦master cable 大线master calibration 主刻度；总调master chart 主控图master check 校正master clock 母钟；时钟脉冲；主脉冲master clock-pulse generator 母时钟脉冲发生器master clutch 主离合器master computer 主机master console 主控制台master control board 主控制板master control gate 总闸门；主控制栅；主控制门master control panel 主控制盘master control program 主控程序master control routine 主控程序master control 主控制master controller 主控制器master curve 理论曲线量板master data 基本数据master design 总体设计master drawing 通用坐标图master end 主动侧master fault 主断层master file 主文件master frequency 主频master gate 总闸门；主控制栅；主控制门master gauge 标准规master gear 主齿轮；标准齿轮master hydraulic control manifold 总液压控制管汇master international frequency list 国际频率总表master joint 主节理master lever 主操作杆master manuscript 原图master map 原始资料图master menu 主菜单master meter calibration unit 标准流量计标定装置master meter method 标准仪表检验法master meter prover 标准流量计检定装置master meter 主表master mode 主方式master mould 原始模型master nozzle 校对喷嘴Master of Science 理科硕士master oscillator 主控振荡器master pattern 原始模型master plan 总平面图master processor 主处理机master profile 标准剖面图master program 主程序master ram =blank rammaster route sheet 总路线表master routine 主程序master sample 标准样品master scale 标准刻度；标准秤master set 校对调整master slave system 主从系统master station amplifier 主台放大器master station 主站master subswitcher 校准用副转换开关master switch 总开关master switcher 校准用转换开关master sync signal 主同步信号master tap 标准丝锥master tape unit 主磁带机master terminal unit 主终端装置master trip 主停机装置master valve 总阀master well course map 井筒走向图master 总的master-slave configuration 主从配置master-slave flip-flop 主从触发器masterbatch colouring 母料着色masterbatch 母料masterpiece 杰作mastership 控制；硕士学位；精通masterslave 主从的masterwork =masterpiecemastery 控制；掌握；优势；精通masthead 桅顶；报头栏；报头mastic coating 胶粘涂料mastic gum 胶粘剂mastic 胶mastication 咀嚼；撕捏；素炼masticator 捏和机；素炼机；搅拌机masut 重油mat bottom 沉垫底部mat deck plan 沉垫甲板图mat fender 绳结护舷软垫mat foundation 底板基础mat support jack-up rig 沉垫自升式钻井平台mat top 沉垫顶部mat 粗糙的MAT 甲醇-丙酮-甲苯MAT 微合金晶体管mat-supported drilling platform 刚性腿座架支承的钻井平台mat-ups 纤维缠结match exponent 对阶match gate 同门match point 拟合点match value 拟合值match 相配matched curve 拟合曲线matched element 匹配元件matched filter 匹配滤波器matched filtering 匹配滤波matched image 匹配图象matched impedance 匹配阻抗matched line 匹配线matched print 立体象对matched-die molding 合模模塑matcher 制榫机；匹配机matching additive 匹配的添加剂matching construction 配套工程matching error 匹配误差matching parameter 匹配参数matching point 平衡工作点matching requirements 装配要求matching 匹配mate 伙伴；副船长material aging 材料老化material balance equation 物质平衡方程material balance method 物质平衡法material balance 物质平衡material behavior 材料特性material cost method 原材料成本法material cycle 物质循环material handling equipment 材料装卸设备material in transit 在途材料material incentive 物质刺激material industry 原材料工业material list 材料明细表material management 物资管理material misrepresentation 实质性表述不当material of spoiled work 损坏工作汇总表material point 质点material purchases 材料采购material requirements planning 库存管理；材料需要量计划material shed 材料棚material shortage 材料紧缺material test 材料试验material 物料material-mud 泥浆料materialism 唯物主义materiality 物质；有形性；重要性；实质性materialization 物质化；具体化；实现materialman 材料员materials engineering menual 材料工程手册materials outside of the state plan 计划外物资materials specification manual 材料规格手册math 数学math 数学的mathematic 数学的mathematical algorithm 数学算法mathematical analysis 数学分析mathematical blocking routine 数学分层程序mathematical expectation 数学期望mathematical forecast 数值预报mathematical geology 数学地质学mathematical homology 数学相当mathematical induction 数学归纳法mathematical justification 数学证明mathematical logic 数理逻辑mathematical model 数学模型mathematical modeling 数学模拟mathematical optimization 数学最优化法mathematical parameterization 数学参数化法mathematical pendulum 数学摆mathematical physics 数学物理学mathematical programming 数学规划mathematical regression 数学回归mathematical relation 数学关系mathematical routine 数学程序mathematical search procedure 数学寻优过程mathematical sedimentology 数学沉积学mathematical simulation 数学模拟mathematical stability 数学稳定性mathematical statistics 数理统计mathematical treatment 数学处理mathematician 数学家mathematics manipulation 数学处理mathematics 数学Matheson and Dresser joint 防漏接头Matheson joint 钟形接头Matin heat resistance test 马丁耐热试验mating endcap 配套堵头mating gear 配对齿轮mating member 配对件mating profile 配对齿廓mating surface 配合面mating 配合Matoniaceae 马通蕨科matric algebra 矩阵代数matrice 矩阵；真值表；母式matrices matrix的复数matrix acidizing 基岩酸化matrix acoustic velocity 基岩中声速matrix algebra 矩阵代数matrix algorithms 矩阵算法matrix arithmetic processor 矩阵运算处理器matrix array algorithm 矩阵数列算法matrix compiler 矩阵编译程序matrix cracking 基质裂化matrix crown 胎体冠部matrix density 岩石骨架密度matrix differential equation 矩阵微分方程matrix display panel 矩阵显示板matrix eigenvalues 矩阵特征值matrix element 矩阵元素matrix encoder 矩阵编码器matrix equation 矩阵方程matrix fibre 基质型纤维matrix gate 矩阵门matrix identification 骨架识别matrix inversion 矩阵求逆matrix iteration 矩阵迭代法matrix keyboard 矩阵键盘matrix limestone 微晶灰岩matrix management 矩阵管理制matrix matching 阵列匹配matrix material 基质matrix memory 矩阵存储器matrix method 矩阵方法matrix mineral 骨架矿物matrix multiplication 矩阵乘法matrix norm 矩阵范数matrix notation 矩阵符号表示matrix of coefficients 系数矩阵matrix operation 矩阵运算matrix organization 矩阵式组织matrix pair 骨架对matrix permeability 原生渗透率matrix polymer 母体聚合物matrix porosity 基岩孔隙度matrix printer 触针式打印机matrix propagator method 矩阵传播函数法matrix representation 矩阵表示matrix skeleton 胎体骨架matrix solid material 造岩物质matrix storage 矩阵存储器matrix store 矩阵存储器matrix stress 基岩应力；基体应力matrix structure 矩阵结构matrix switch 矩阵开关matrix topology 骨架拓扑结构matrix trace 矩阵的迹matrix type structure 矩阵式结构matrix velocity 骨架速度matrix 填质matrix-banding scheme 矩阵列图matrix-fibre interface 基质-纤维界面matrix-fibril bicomponent fibre 基质-原纤型双组分纤维matrixer 矩阵变换电路matrixing 换算matrosite 孢芽油页岩matte print 无光相片matte surface 无光面matte 无光泽的matted staple 并结短纤维matter wave 物质波matter 物质matting agent 消光剂matting 席子；编席；褪光；无光表面；清洗工序mattock 鹤嘴锄mattress 褥垫；钢筋网maturation factor 成熟因子maturation gradient 熟化梯度maturation index 成熟指数maturation period 熟化期maturation products 成熟产物maturation 成熟maturative 促进成熟的mature gas 成熟气mature index 成熟指数mature mud 充分水化的泥浆mature river 壮年河mature sandstone 成熟砂岩mature stage 壮年期mature topography 壮年地形mature turbidite 成熟浊积岩mature waterflood 成熟注水mature 成熟matured note 到期票据maturing colonies 成熟的菌落maturing field 老油田maturity book 到期日记簿maturity index 成熟度指数maturity stage 成熟期maturity 成熟度；壮年；到期maul 大槌；殴打；刺破；弄乱mauve 苯胺紫；紫红色mavel 奇迹；奇观；惊异max cap. 最大容量max-flow-min-cut theorem 极大流转极小割截定理max-value function 极大值函数Max. hp. 最大马力max. 最大Maxalog 射流逻辑元件MAXI brake 弹簧安全刹车maxim 原理；谚语；最大值maxima maximum的复数maximal draw ratio 最大拉伸比maximal invariant 极大不变量maximal value 最大值maximal 极大maximal-flow algorithm 最大流量算法maximax criterion 极大极大准则maximin 极大化极小maximised locking force 最大闭锁力maximization 极大化maximize 使达到最大值maximizing 达到最大值maximum adiabatic flame temperature 最高绝热火焰温度maximum allowable weight on bit 大允许钻压maximum allowed dose 最大容许剂量maximum allowed presure drop 最大允许压力降maximum available gain 最大可用增益maximum bubble pressure method 最大泡点压力法maximum coherency filtering 最大相干滤波maximum convexity migration 最大凸点偏移maximum convexity 最大凸率maximum crest 最大峰值maximum design condition 最大设计条件maximum design pressure 最高设计压力maximum disk capacity 最大磁盘容量maximum displacement 最大顶替量maximum drilling string load 最大钻柱载荷maximum elevation 最大高程maximum entropy method 最大熵法maximum entropy spectrum 最大熵谱maximum error 最大误差maximum extension 最大扩张maximum flow 最大流量maximum frequency 最大频率maximum glaciation 最大冰期maximum hydraulic horsepower 最大水马力maximum inventory 最大库存量maximum lift 最大举升力maximum likelihood classifier 最大似然分级器maximum likelihood estimator 极大似然估计量maximum likelihood 最大似然率maximum no effect level 最大无影响剂量maximum norm 最大模maximum offset 最大偏移距maximum operation frequency 最高工作频率maximum output 最大输出maximum parallelism degree 最大并行度maximum penetration rate 最高钻速maximum penetration 最大穿透深度maximum permeability 最大磁导率maximum permisible service temperature 最高允许使用温度maximum permissible concentration 最大允许浓度maximum permissible dogleg 最大允许狗腿maximum permissible rate 最大允许产量maximum phase 最大相位maximum polished rod load 悬点最大载荷maximum possible rate 最大可能产量maximum pressure rating 最大压力额定值maximum pulling capacity 最大提升能力maximum queue length 最大排队长度maximum rainfall 最大降雨量maximum recording thermometer 最高读数温度计maximum recovery rate 最大开采速度maximum relay 过载继电器maximum safe limit 安全极限maximum safe working pressure 最高安全工作压力maximum sand free production 最高无砂产量maximum saturation condition 最大饱和条件maximum shear 最大剪应力maximum slope 最大斜率maximum span 最大跨度maximum stacking velocity 最大叠加速度maximum stiffness 最大刚度maximum stress 最大应力maximum surge pressure 最大水击压力maximum term 极大项maximum test pressure 最大试验压力maximum thermometer 最高温度计maximum tolerated dose 最大耐受剂量maximum transfer rate 最大传送率maximum turnover 最高周转率maximum twist number 断裂捻数maximum uncertainty 最大不确定性maximum vacuum 最大真空度maximum value 极大值maximum variance norm deconvolution 最大方差模反褶积maximum water 油井固井中最高水灰比maximum 最大maximum-delay 最大延迟maximum-likelihood criterion 最大似然准则maximum-likelihood deconvolution 最大似然反褶积maximum-reading thermometer 最高读数温度计maxipulse 最大脉冲法MAXIS 多功能数据采集和成象系统maxmin criterion 最大最小准则maxmin strategy 极大化极小策略Maxwell equation 麦克斯韦方程式maxwellmeter 磁通计mayberyite 富硫石油mayday 无线电话中求救信号mayonnaise sludge 发动机低温淤渣Maysvillian 迈斯维尔阶mazarine 深蓝色maze 迷宫mazut =masutmazy 迷宫式的MB 磁方位角MB 存储缓冲器MB 电磁制动器MB 多频带mb 毫巴mb 毫靶MB 信箱Mb 兆位MB 兆字节MB 主电池MBB 磁吹灭弧断路器MBB 先接后断MBPD 千桶日MBS 叠前偏移MBSIM 多波束扫描成图法MBT 亚甲基蓝测定法MBT 主边界逆掩断层MBT 主压载水舱Mbytes 兆字节MC 边缘校验MC 磁心MC 电磁离合器MC 复式接点mc 毫居里MC 机器MC 机器合格证MC 米-烛光MC 米制克拉mc 泥饼MC 人工控制MC 瞬时接触MC 微居里MC 维修中心MC 小型电容器Mc 兆居里MC 兆周MC 主控制MCA 除泥浆堵塞化学剂MCA 多道分析器MCA 泥酸MCC 短周期计数器MCC 多片电路MCC 马达控制中心MCC 主控制台MCD 磁力裂缝探测MCD 多臂井径仪MCD 最低成本钻井MCF 多道滤波器MCF 多道相干滤波器MCF 千立方英尺MCFCD 千英尺 3 日历日MCFPD 千英尺 3 日MCGS 微波指令制导系统mCi 毫居mckittinite 地沥青MCLT 套管磁测井仪MCM 多次接触混相MCOGA 中陆地区油气协会MCOR 泥浆校正MCP 多道信息处理机MCP 制造更改要点MCP 主控程序mcps 兆赫MCS 多道定标MCS 计算机科学硕士MCS 主控装置MCSB 多路传输通道选择位MCSI 多路传输通道选择禁止MCST 泥饼样品温度MCT 机械切割式井壁取心器MCT 主要中央逆掩断层MCtr 主控制器MCtt 电磁接触器MD 测量深度MD 磁鼓md 毫达西md 量测井深MD 平均偏差MD 图上距离MD 质量检测器Md 钔MD-Macr 磁鼓宏指令MDA 最小检出放射性强度mdarcy 毫达西MDAS 多光谱数据分析系统MDC 磁鼓控制器mdd 毫克分米 2 ·日MDDPM 磁鼓数据处理机MDEC 磁偏角MDEN 骨架密度MDET 矿物鉴别MDF 市场需求因素MDF 总配线架MDH analysis 米勒-戴斯-赫钦森试井分析法MDH graphs 米勒型处理压力恢复资料的图解法MDH-type curve MDH型曲线MDIA 平均井径mdl 中央；中间的；中等的MDP 最大排出压力MDR 被乘数-除数寄存器MDR 多道数据记录器MDR 甲基二苯噻吩二苯噻吩比值MDR 任务数据简化MDS 故障探测系统MDS 最小可辨信号mdse. 商品；货物MDT 平均停工期MDTL 改进的二极管晶体管逻辑MDU 移动式潜水装置ME 测量元件ME 存储误差ME 分子电子学ME 管理技术ME 机械效率Me 甲基ME 设备维修ME 制造工艺ME 中东ME 主机ME 最小仰角；最低高度MEA 单乙醇胺meacon 错误信号发生设备；虚造干扰meadow bog 草甸沼泽meadow peat 草甸泥炭meadow 牧场；草地meager profit 微利meagre coal 贫煤mean absolute deviation 平均绝对偏差mean absolute error 平均绝对误差mean activity 平均活度mean anomaly 平均导常mean approximation 平均近似mean arrival rate 平均到达率mean asperity height of fracture face 裂缝面平均粗糙度mean average boiling point 中平均沸点mean carrier velocity 平均载气线速mean curvature 平均曲率mean deriation 均差mean deviation 平均偏差mean diameter 平均直径mean difference 均差mean displacement rate 平均驱替速度mean distance 平均距离mean dose 平均剂量mean effective pressure 平均有效压力mean effective value 平均有效值；均方根值mean error 平均误差mean fibre length 纤维平均长度mean fibre width 纤维平均宽度mean forward current 平均正向电流mean free error time 平均无故障时间mean free path 平均自由程mean geometrical distance 几何平均距离mean grain size 平均粒径mean heat capacity 平均热容量mean high tide 平均高潮面mean high-water level 平均高水位mean hydraulic radius 平均水力半径mean indication pressure 平均指示压力mean life 平均寿命mean lifetime 平均寿命mean line 等分线mean linear range 平均直线射程mean low level 平均低潮面mean low water 平均低潮面mean low-water level 平均低水位mean matrix 平均矩阵mean molal heat capacity 平均克分子热容mean molar quantity 平均摩尔数量mean molecular weight 平均分子量mean multiplier gain 倍增管平均增益mean neutron lifetime 中子平均寿命mean normal intension 平均法向强度mean pair product 平均偶积mean parameter 平均参数mean particle size 平均颗粒大小mean permeability 平均渗透率mean pressure 平均压力mean proportional 比例中项mean radius 平均半径mean range 平均距离；平均射程；平均自由程；平均极差；平均潮差mean rate 平均速率mean relative deviation 平均相对偏差mean replacement static 平均置换静校正mean reservoir pressure 平均地层压力mean scale 平均比例尺mean sea depth 平均海水深度mean sea level 平均海平面mean service rate 平均服务率mean specific heat 平均比热mean square deviation 均方差mean square dip 均方地层倾角mean square error 均方误差mean square modulus 均方模mean square regression 均方回归mean square root 均方根mean square slowing-down length 均方慢化长度mean square value 均方值mean square 均方mean stress 平均应力mean temperature difference 平均温差mean time between failures 平均故障间隔时间mean time to failure 平均初次出故障时间mean value 平均值mean vector 均值向量mean velocity 平均速度mean water level 平均水平面mean wave 平均波mean 中间的；平均的；中项；平均值mean-square channel diameter 均方孔道直径mean-trace 平均道meander amplitude 曲流幅度meander bar 曲流沙坝meander belt 曲流河段meander bend 河曲meander breadth 河曲宽度meander curve 曲流meander cut-off 曲流裁弯取直meander line 折测线meander loop 河曲的环状河道meander migration 河曲迁移meander reach 曲流段meander scroll 曲流内侧坝meander trough 曲流槽meander 河曲meandering course 曲流meandering river 曲流河meandering tidal channel 弯曲潮道meandering valley 曲流河谷meandering 曲折的meaningless 无意义的；失效means of livelihood 生活资料means of recourse 追索办法means of transportation 运输手段；运输工具means 方法means-end analysis 手段和目的分析meantime 时隔时间；其间meanwhile =meantimemeas 量measurability 可测性measurable anomaly 可测异常measurable property 可测特性measurable 可测的measurand 被测物理量measuration =measurement measure analysis 体积分析measure expansion 体膨胀measure in 下钻测算井深measure kelly overstand 量方余measure of skewness 偏斜度measure of value 定值；价值尺度measure out 起钻测算井深measure point 测量点measure up to 够得上measure 量测；量度measured depth 量测深度；量测井深measured deviation 测量误差measured direction 实测方位measured distance 实测距离measured drilling depth 量测的井深measured inclination 测量的井斜角measured profile 实测纵断面measured reserves 测定储量measured section 实测剖面measured signal 被测信号measured value 实测值measured 实测的measurement accuracy 量测精度measurement capacity 载货容量measurement crew 划线小组measurement error 测量误差measurement goods 按体积计运费货物measurement inaccuracy 测量误差measurement instrument 测量仪表measurement matrix 测量矩阵measurement noise 测量噪音measurement of angle 角度测量measurement of azimuth 方位角测量measurement of bearing 方位测量。

211036557_聚苯乙烯纳米塑料在小鼠组织和细胞水平的累积分布规律及动态毒性响应

生态毒理学报Asian Journal of Ecotoxicology第18卷第1期2023年2月V ol.18,No.1Feb.2023㊀㊀基金项目:浙江省基础公益研究计划资助项目(LTGY23B070001);浙江中医药大学校级科研基金资助项目(2020ZG29);浙江中医药大学中青年科研创新基金资助项目(KC201920)㊀㊀第一作者:陈煊威(1996 ),男,硕士研究生,研究方向为环境毒理学,E -mail:************************.cn ㊀㊀*通信作者(Corresponding author ),E -mail:********************.cnDOI:10.7524/AJE.1673-5897.20220523001陈煊威,许健,陈瑾.聚苯乙烯纳米塑料在小鼠组织和细胞水平的累积分布规律及动态毒性响应[J].生态毒理学报,2023,18(1):351-360Chen X W,Xu J,Chen J.Cumulative distribution and dynamic toxicity response of polystyrene nanoplastics at tissue and cell levels in mice [J].Asian Journal of Ecotoxicology,2023,18(1):351-360(in Chinese)聚苯乙烯纳米塑料在小鼠组织和细胞水平的累积分布规律及动态毒性响应陈煊威,许健,陈瑾*浙江中医药大学医学技术与信息工程学院,杭州310053收稿日期:2022-05-23㊀㊀录用日期:2022-08-09摘要:环境中的纳米塑料已证实能被动物摄取并在体内累积,成为潜在的生物危害因素㊂为阐明纳米塑料在组织和细胞水平的分布和积累规律及其毒性动态规律,本研究分别通过纳米聚苯乙烯塑料(PS -NPs)灌胃BALB/c 小鼠和进行RAW264.7巨噬细胞暴露,研究纳米塑料急㊁慢性暴露时的体内分布规律和细胞动态应激响应规律㊂结果表明,PS -NPs 在小鼠灌胃1h 内,即从胃向肠道转移,24h 后基本代谢完全;但慢性暴露21d 在胃肠道发现严重炎性损伤㊂细胞吞噬动力学结果显示8h 内胞内积累的PS -NPs 量随时间线性增长,随后下降,在12h 后趋于稳定;同步诱导胞内活性氧(ROS)水平显著上升,8h 内与PS -NPs 胞内含量成正相关,但对炎性因子TNF -α和IL -6的诱导效应与进入细胞的PS -NPs 量不相关㊂PS -NPs 对TNF -α的激活效应显著高于IL -6,表明主要引起细胞免疫反应㊂本研究结果将有助于纳米塑料的生物危害性及人群健康风险评估,尤其警惕长期低剂量的暴露风险㊂关键词:纳米塑料;巨噬细胞;氧化损伤;动态分布文章编号:1673-5897(2023)1-351-10㊀㊀中图分类号:X171.5㊀㊀文献标识码:ACumulative Distribution and Dynamic Toxicity Response of Polystyrene Nanoplastics at Tissue and Cell Levels in MiceChen Xuanwei,Xu Jian,Chen Jin *School of Medical Technology and Information Engineering,Zhejiang Chinese Medical University,Hangzhou 310053,ChinaReceived 23May 2022㊀㊀accepted 9August 2022Abstract :Nanoplastics in the environment have been confirmed to be ingested and accumulated in animal body,and become a potential biohazard factor.In order to elucidate the distribution and accumulation of nano -plastics in tissues and cells and their dynamic toxicity,BALB/c mice and RAW264.7macrophages were selected to respective -ly study the in vivo distribution and dynamic stress response of cells during acute and chronic exposure of polysty -rene nanoplastics (PS -NPs).The results showed that PS -NPs was transferred from stomach to intestinal tract within 1h ㊀in mice after gavage,and were basically metabolized after 24h.However,severe inflammatory damage was found in the gastrointestinal tract after chronic exposure for 21d.The results of phagocytosis kinetics showed that the amount of PS -NPs accumulated in macrophages increased linearly with time within 8h and became stable after352㊀生态毒理学报第18卷12h.Intracellular reactive oxygen species(ROS)level increased synchronously,and was positively correlated with the intracellular content of PS-NPs within8h.Whereas,the induction effect on the inflammatory factors TNF-αand IL-6was independent of the PS-NPs amount entered into cells.The activation effect of PS-NPs on TNF-αwas significantly higher than that of IL-6,indicating that it mainly caused cellular immune response.The results of this study is contributable to the assessment of biohazardous and human health risks of nanoplastics,especially the risk of long-term and low-dose exposure.Keywords:nanoplastics;macrophage;dynamic distribution;oxidative damage㊀㊀塑料的广泛使用带来了极为严重的环境问题,环境中的塑料垃圾降解可生成更小的微塑料(micro-plastics,MPs;1μm~5mm)和纳米塑料(nanoplastics, NPs;<1μm)㊂多项针对环境的调查研究指出微塑料在海洋㊁土壤㊁湖泊㊁河流和水库等环境中均有分布,水体中塑料浓度从24.8个㊃m-3到10200个㊃m-3不等,而土壤中含量更高,平均为18760个㊃kg-1[1-5]㊂环境中塑料丰度整体呈现随粒径变小而指数增长的趋势,预测50nm的塑料颗粒浓度是5μm的3倍以上[6]㊂环境中塑料成分主要为聚乙烯(polyethylene,PE)㊁聚丙烯(polypropylene,PP)㊁聚苯乙烯(polystyrene,PS)㊁聚对苯二甲酸乙二酯(PE terephthalate,PET)和聚甲基丙烯酸甲酯(polymethyl methacrylate,PMMA),其中聚苯乙烯常用于制作一次性餐盒㊁保温材料等,且在自然环境中较难降解,也因此成为研究的热点[7]㊂环境中的微/纳米塑料可以通过饮食㊁饮水等途径被动物摄入,在鱼㊁虾和双壳类动物的肠道㊁肌肉和腮中均检测到微塑料颗粒[8]㊂哺乳动物进而通过饮水㊁食用海产品㊁海盐等方式摄入微/纳米塑料㊂近年在人体粪便和肠道中检出微塑料,给出了人体摄入塑料颗粒的直接证据[9-10];Leslie等[11]的最新研究证实人体血液中存在塑料颗粒,表明塑料颗粒可进入血液循环系统,造成多器官暴露㊂小鼠动物模型表明纳米塑料较微米尺度塑料具有更强生物富集性,因其小粒径更易被肠道上皮细胞吸收并通过循环系统,在肝脏中积累,甚至穿过血脑屏障和生殖屏障富集于大脑㊁睾丸等组织[12]㊂但是不同研究之间的塑料颗粒积累规律及毒性效应有较大差异[13]㊂Meng等[14]用50nm的纳米聚苯乙烯颗粒(PS-NPs)灌胃小鼠(5mg㊃d-1)4周,发现PS-NPs在肠道和肾脏蓄积并造成组织结构损伤,诱导血清超氧化物歧化酶(SOD)㊁过氧化氢酶(CAT)和谷胱甘肽(GSH)等抗氧化酶活性上升;然而Nikolic等[15]使用40nm的PS-NPs暴露小鼠(0.1mg㊃d-1)5周却未在肾脏中发现PS-NPs的积累,主要分布在胃㊁肠道和睾丸生精小管,并导致睾丸激素水平下降和IL-23等炎症因子表达上升㊂因此不同暴露剂量和暴露周期可能影响塑料颗粒的代谢动力学过程,需进一步动态监测纳米塑料摄入后的组织乃至细胞水平分布规律,以明确其主要作用靶器官和致毒机制㊂纳米塑料通过饮食摄入后在胃肠道主要被巨噬细胞吞噬,上调炎症因子表达,诱导炎症细胞的浸润,引起肠道炎症反应[16]㊂巨噬细胞被称为肠道免疫系统的守卫 ,通过识别有害病原菌及异物,维持肠道免疫系统平衡㊂Kuhn等[17]证明纳米塑料可通过大胞饮㊁吞噬作用及网格蛋白介导的内吞作用进入巨噬细胞㊂体外研究发现,小鼠巨噬细胞RAW264.7暴露于100μg㊃mL-1的PS-NPs4h便会导致活性氧(ROS)大量产生,诱导细胞氧化应激损伤[18-19]㊂但纳米塑料在胞内的动态累积分布规律及毒性动态响应仍不明确㊂本研究通过对小鼠进行PS-NPs灌胃处理,研究塑料在小鼠胃肠器官中的动态积累规律及造成的病理损伤;进一步用小鼠巨噬细胞RAW264.7为模型,在细胞水平探讨PS-NPs细胞内暴露剂量及细胞应激响应,揭示纳米塑料细胞毒性的时间效应规律,为后续对环境塑料污染健康风险评估提供依据㊂1㊀材料与方法(Materials and methods)1.1㊀试剂本研究采用的纳米聚苯乙烯(绿色㊁红色荧光标记和无荧光标记,平均粒径80nm,货号分别为7-3-0008㊁7-1-0008㊁6-1-0006,成分为90%苯乙烯+10%甲基丙烯酸甲酯(MMA),纯度90%)购自天津市倍思乐色谱技术开发中心;ROS试剂盒购自碧云天生物技术有限公司(货号:S0033S);IL-6(货号:EK206/3-96)㊁TNF-α(货号:EK282HS-96)ELISA试剂盒购自杭州联科生物技术股份有限公司;胎牛血清(FBS)购自浙江天杭生物科技股份有限公司(货号:11011-8611); DMEM培养基购自Gibco(货号:C11995500BT)㊂第1期陈煊威等:聚苯乙烯纳米塑料在小鼠组织和细胞水平的累积分布规律及动态毒性响应353㊀1.2㊀实验动物和细胞BALB/c小鼠购自上海BK公司,饲养在浙江中医药大学动物中心,环境室温(23ʃ2)ħ,相对湿度45%~60%,昼夜交替周期为12h,在环境中适应一周,期间自由饮水㊁摄食㊂实验方案经浙江中医药大学实验动物伦理要求批准㊂RAW264.7细胞购自中国科学院上海细胞库,使用含10%FBS的DMEM 培养㊂1.3㊀实验方法动态光散射(DLS)测定㊂用含有10%FBS的DMEM培养液配制浓度为1mg㊃mL-1的PS-NPs,并将悬液在60W功率下(开4s关1s)超声处理10 min㊂稳定20min后,通过动态光散射仪(Zetasizer Nano Series,Malvern)测量它们的团聚性,包括流体动力学尺寸和Zeta电位㊂体内分布检测㊂提前一天剔除小鼠体毛,第2天灌胃1.5mg红色荧光标记的PS-NPs,分别在10 min㊁30min㊁1h和24h使用IVIS LuminaⅢ小动物活体成像系统的cy5通道检测小鼠体内红色荧光分布和强度㊂病理学检测㊂将20只小鼠随机分为4组,每组5只,分别灌胃无菌水㊁0.015㊁0.15和1.5mg㊃d-1PS-NPs连续21d,处死后取胃肠组织,经4%多聚甲醛固定㊁梯度酒精脱水㊁二甲苯透明㊁浸蜡㊁包埋㊁切片㊁展片和黏片后,进行苏木素-伊红(HE)染色,中性树脂封片,镜下观察㊂细胞摄取测定㊂参考Liu等[20]方法借助塑料颗粒标记荧光强度定量PS-NPs在胞内的含量,首先将绿色荧光标记的PS-NPs用含10%FBS的DMEM培养液,按10倍梯度进行稀释,配制成0.001㊁0.01㊁0.1㊁1㊁10㊁100㊁1000μg㊃mL-1的PS-NPs 悬液,并利用流式细胞仪(CytoFLEX,Bechman Coul-ter)吸取200μL悬液检测荧光强度,制作PS-NPs荧光强度-颗粒含量的标准曲线㊂将RAW264.7细胞以5 104个㊃mL-1密度种于12孔培养板上,用100μg㊃mL-1的绿色荧光标记的PS-NPs处理1~24h后,用不含EDTA的胰酶消化后离心再用PBS重悬离心清洗2次后,以200μL 的PBS重悬,过200目筛网,用流式细胞仪检测荧光强度㊂活性氧测定㊂将细胞以5 104个㊃mL-1密度种于培养板上,用100μg㊃mL-1的无荧光标记的PS-NPs处理1~24h后,以不含血清的DMEM清洗2次,加入以不含血清的DMEM稀释1000倍的DCFH-DA探针孵育30min,再用不含血清的DMEM清洗2次,用不含EDTA的胰酶消化后离心再用PBS重悬离心清洗2次后,以200μL的PBS 重悬,过200目筛网,用流式细胞仪检测ROS水平㊂ELISA测定㊂将细胞以5 104个㊃mL-1密度种于培养板上,以100μg㊃mL-1浓度的无荧光标记的PS-NPs刺激细胞1~24h后,收集上清液,300g离心10min取上清用ELISA试剂盒检测IL-6和TNF-α㊂1.4㊀数据处理使用GraphPad Prism8和SPSS26进行数据分析,所有试验设置3组平行㊂实验结果以平均值ʃ标准差呈现,采用单因素方差分析(One-way ANO-V A)处理组与对照组的显著性差异,以P<0.05为差异有统计学意义㊂2㊀结果(Results)2.1㊀PS-NPs的流体动力学分析通过DLS测量在培养液环境中,PS-NPs粒子的颗粒大小和团聚情况㊂结果表明,55.2%的PS-NPs颗粒在培养液中的粒径集中在100~200nm,团聚粒径为131.3nm,Zeta为-13.8mV,未发生明显团聚(图1和表1)㊂图1㊀纳米聚苯乙烯塑料(PS-NPs)在细胞培养液中的粒径分析Fig.1㊀Particle size analysis of polystyrene nanoplastics(PS-NPs)in cell culture medium354㊀生态毒理学报第18卷2.2㊀PS -NPs 在小鼠体内的分布规律及病理损伤对BALB/c 小鼠灌胃1.5mg PS -NPs 后,小鼠体内的分布和转移结果如图2所示㊂在灌胃后1h 内,PS -NPs 逐步从胃向肠道转移,而在24h 后,仅在肠道有少许PS -NPs 残留能检测到荧光信号㊂急性暴露后(24h),本实验剂量PS -NPs 并未对胃肠道造成明显病理损伤,但在对BALB/c 小鼠灌胃PS -NPs 21d 后(低剂量0.015mg ㊃d -1,中剂量0.15mg ㊃d -1,高剂量1.5mg ㊃d -1),发现和对照组相比,经PS -NPs 暴露的小鼠消化道存在不同程度的病理性损伤,胃肠道腺体明显减少,炎症细胞大量浸润(箭头所示),且随暴露浓度的增加,组织受损程表1㊀PS-NPs 在细胞培养液中的水动力学特征分析Table 1㊀Hydrodynamic analysis of PS -NPs in cell culture medium原始粒径/nm Original particle size/nm团聚粒径/nmAgglomerated particle size/nmZeta 电位/mV Zeta potential/mV60131.3-13.8图2㊀灌胃24h 内PS-NPs 在小鼠体内的分布和转运注:(a)PS -NPs 在24h 内的体内转运和分布;(b)小鼠口腔㊁胃和肠道24h 内PS -NPs 的定量分析㊂Fig.2㊀Distribution and transport of PS -NPs in mice within 24h after gavageNote:(a)Transport and distribution of PS -NPs in vivo within 24h;(b)Quantitative analysis of PS -NPs in the oral cavity,stomach and intestinal tract of mice within 24h.第1期陈煊威等:聚苯乙烯纳米塑料在小鼠组织和细胞水平的累积分布规律及动态毒性响应355㊀度也愈发严重,如图3所示㊂2.3㊀PS -NPs 在RAW264.7细胞中的动态分布根据纳米塑料荧光强度与浓度的关系得到标准曲线y =1337.28+2133.23x (R 2=0.99)(图4),验证准确率bias 为-4.152%,回收率108.7%㊂通过荧光信号对胞内PS -NPs 进行动态示踪,并根据荧光强度与颗粒含量的线性关系来定量PS -NPs 的胞内剂量㊂观察RAW264.7细胞PS -NPs 暴露1~24h 的纳米塑料摄入量,结果表明PS -NPs 在细胞暴露的前8h ,胞内的塑料颗粒含量呈线性增加(y =-3.86888+3.4436x ,R 2=0.99),到8h 到达峰值;随后至24h ,含量下降趋于稳定(图5(a))㊂图3㊀PS-NPs 灌胃后小鼠胃肠道HE 染色观察注:1000 放大倍数,箭头指示炎症细胞浸润㊂Fig.3㊀HE staining observation of mouse gastrointestinal tract after intragastric administration of PS -NPsNote:1000 magnification,arrows indicate inflammatory cellinfiltration.图4㊀PS-NPs 含量与荧光强度的拟合曲线Fig.4㊀Fitting curve of PS -NPs concentrationand fluorescence intensity2.4㊀PS -NPs 诱导RAW264.7细胞内氧化应激损伤PS -NPs 被巨噬细胞吞噬后可诱导胞内氧化应激损伤[21],本研究具体探讨其产生活性氧的动态规律,结果表明在24h 内,ROS 的产生总体呈现正弦函数波形分布;在前12h 内具有较好的线性递增规律(y =-1205.77+2751.24x ,R 2=0.96)(图6(b)),但在16~20h ROS 大幅下降,而在24h 再次增强(图6(a))㊂ROS 的产生与胞内PS -NPs 的累积在8h 内呈显著正相关(皮尔逊相关系数0.9821)(图7(b)),而在8h 后胞内含量变化与ROS 的产生并不同步㊂2.5㊀PS -NPs 诱导RAW264.7细胞内炎性因子表达规律㊀㊀在动物水平观察到PS -NPs 暴露后有明显的炎症细胞浸润,进而在细胞水平分析其诱导炎性因子产生规律㊂使用ELISA 试剂盒检测经PS -NPs 暴露后的IL -6和TNF -α的表达,结果显示TNF -α表达量在1h 后便急剧上升,且随时间延长基本趋于稳定;但是PS -NPs 诱导IL -6的表达仅在24h 后才有显著的上升(图8)㊂同时炎症因子的上调与胞内PS -NPs 的积累并无显著相关性(TNF -α的皮尔逊相关系数为0.572,IL -6为0.332)㊂356㊀生态毒理学报第18卷图5㊀PS-NPs 在RAW264.7细胞内随时间的积累情况注:(a)PS -NPs 在RAW264.7细胞中24h 内的累积情况;(b)PS -NPs 在RAW264.7细胞中8h 内的累积情况(*P <0.05)㊂Fig.5㊀The accumulation of PS -NPs in RAW264.7cells over timeNote:(a)Accumulation of PS -NPs in RAW264.7cells within 24h;(b)Accumulation of PS -NPs in RAW264.7cells within 8h (*P<0.05).图6㊀PS-NPs 在不同时间点刺激RAW264.7细胞产生的活性氧(ROS )水平注:(a)PS -NPs 在24h 内诱导的ROS 水平;(b)PS -NPs 在12h 内诱导的ROS 水平(*P <0.05)㊂Fig.6㊀The reactive oxygen species (ROS)levels induced by PS -NPs in RAW264.7cells at different time pointsNote:(a)ROS levels induced by PS -NPs within 24h;(b)ROS levels induced by PS -NPs within 12h (*P <0.05).3㊀讨论(Discussion )近年在市售的瓶装矿泉水㊁海鲜㊁海盐和饮用茶包中均发现塑料颗粒,引发对塑料颗粒通过饮食途径摄入造成人体暴露风险的高度关注[9-10]㊂动物模型已证实通过饮食途径摄入的微/纳米塑料颗粒不仅会在肠道大量沉积,影响肠道结构功能,还会在肝脏㊁肾脏和肺积累,造成脏器的损伤,尤其纳米粒径颗粒能透过生殖屏障和血脑屏障(表2)㊂但不同研究暴露时间不同,不能阐明其迁移规律㊂本研究以小鼠为模型,模拟了纳米塑料摄入后对胃肠道的动态积累影响,结果表明通过饮食途径摄入的纳米塑料在1h 内快速由胃向肠道转移,但是在24h 内荧光信号已衰减至难以检测,可能是一部分纳米塑料随代谢物排出体外,如Peng 等[22]用串联液相色谱质谱检测到,大鼠通过粪便排泄纳米聚酰胺的半衰期为36.9h ;另一部分纳米塑料可能进入血液循环系统迁移至其他器官富集,后续我们将进一步研究不同器官的PS -NPs 积累情况㊂本研究表明PS -NPs 急性暴露并不对会胃肠道有明显的影响,但长期暴露下,存在剂量依赖的炎症效应,表明即使是低剂量第1期陈煊威等:聚苯乙烯纳米塑料在小鼠组织和细胞水平的累积分布规律及动态毒性响应357㊀的摄入也会因为累积效应造成严重的组织结构损伤㊂小鼠肠道的病理分析表明PS -NPs 暴露导致了大量炎症细胞的浸润,其中肠道巨噬细胞是其免疫功能的重要执行者,进入肠道的塑料颗粒主要被巨噬细胞吞噬,从而维持其肠道稳态[33]㊂本研究在细胞水平上探索了PS -NPs 被巨噬细胞吞噬的动力学规律及其对细胞的急性毒性㊂研究结果表明,纳米塑料被细胞吞噬同时存在吐出的代谢过程,如Liu 等[20]在大鼠嗜碱性粒细胞中研究50㊁500和5000nm 粒径的PS 塑料颗粒转运规律,发现胞内的PS 浓度也在8h 时达到峰值,随后开始下降;且撤除暴露源后,再培养基中观察到塑料颗粒,证实细胞存在外排机制㊂本实验中,在8h 内塑料颗粒进入细胞的量与时间呈显著正相关,而12h 后,胞内的塑料颗粒趋向于饱和,表明开始细胞对塑料的摄入量大于排出量,最后二者达成动态平衡,使得胞内的塑料颗粒数量维持在稳定状态,但是巨噬细胞对纳米塑料的胞吞㊁胞吐调控机制有待进一步明晰㊂图7㊀PS-NPs 诱导细胞产生的ROS 水平与其胞内含量的相关性分析注:(a)PS -NPs 在24h 内诱导的ROS 水平与其胞内含量之间的相关性分析;(b)PS -NPs 在8h 内诱导的ROS 水平与其胞内含量之间的相关性分析㊂Fig.7㊀Correlation analysis of ROS levels induced by PS -NPs in RAW264.7cells and their intracellular massNote:(a)Correlation analysis between the level of ROS induced by PS -NPs within 24h and its intracellular content;(b)Correlation analysis between the level of ROS induced by PS -NPs within 8h and its intracellularcontent.图8㊀PS-NPs 在不同时间点刺激RAW264.7细胞产生的炎症因子水平注:(a)PS -NPs 诱导的细胞TNF -α表达水平;(b)PS -NPs 诱导的细胞IL -6表达水平(*P <0.05)㊂Fig.8㊀The levels of inflammatory factors induced by PS -NPs at different time pointsNote:(a)The level of TNF -αinduced by PS -NPs;(b)The level of IL -6induced by PS -NPs (*P <0.05).358㊀生态毒理学报第18卷表2㊀微/纳米塑料暴露的体内分布和毒性结果统计Table2㊀A statistical table of toxicity and distribution of microplastics and nanoplastics塑料种类Kind of plastic暴露方式Way of exposure暴露时间Time of exposure主要累积部位Main accumulation site主要效应Main effect文献ReferencesPS㊁PS-COOH㊁PS-NH2(80nm)吸入Inhalation7d大脑㊁肝Brain,liver神经毒性Neurotoxicity[23]PS(100nm㊁3μm㊁10μm)灌胃Gavage4h肠㊁肝㊁脂肪Intestine,liver,fat未检测Undetected[24]PS(4μm㊁10μm)灌胃Gavage28d睾丸Testis破坏生殖屏障Disruption of reproductive barrier[25]PS(20nm㊁220nm㊁1μm㊁6μm)灌胃Gavage48h胃㊁肠Stomach,intestine未检测Undetected[26]PS(50nm㊁500nm㊁5μm)灌胃Gavage28d胃㊁肠Stomach,intestine破坏肠道屏障Disruption of intestinal barrier[27]PS㊁PS-COOH㊁PS-NH2(100nm)灌胃Gavage28d胃㊁肠㊁睾丸㊁肾Stomach,intestine,testis,kidney局部炎症Local inflammation[12]PS(5μm㊁20μm)灌胃Gavage28d肝㊁肾㊁肠Liver,kidney,intestine脂质代谢异常Abnormal lipid metabolism[28]PE(10~150μm)混入食物Added to food5周5weeks肠Intestine肠道菌群失调㊁炎症Alteration of intestinal flora,inflammation[29]PS(5μm)混入饮水Dissolvedin drinking water28d未统计Uncounted加重DSS诱导的结肠炎Exacerbation of DSS-induced colitis[30]PS(157nm)尾静脉注射Tail vein injection21d肝㊁肺㊁脂肪Liver,lung,fat血糖升高㊁脂质代谢异常Elevated blood glucose,abnormal lipid metabolism[31]PS(50nm)灌胃Gavage7d肠㊁脑Intestine,brain破坏血脑屏障㊁炎症Disruption of blood-brain barrier,inflammation[32]注:PS-COOH表示表面用羧基修饰的PS-NPs,PS-NH2表示表面用氨基修饰的PS-NPs;PE表示聚乙烯;DSS表示葡聚糖硫酸钠㊂Note:PS-COOH means carboxyl functionalized PS-NPs,PS-NH2means amino functionalized PS-NPs;PE means polyethylene;DSS means dextransul-fatesodium.㊀㊀细胞对纳米塑料的应激响应主要为氧化应激损伤及炎症反应㊂我们的研究也证明PS-NPs在进入细胞后会刺激细胞产生氧化应激损伤,并在12h内与PS-NPs浓度成正相关,随后ROS水平下降,这可能是由于细胞内超氧化物歧化酶㊁过氧化氢酶和谷胱甘肽过氧化物酶等抗氧化物酶被活化,激活胞内抗氧化机制[34]㊂在细胞炎症响应上,PS-NPs对TNF-α表现出较明显的激活作用,但只诱导极少量的IL-6产生,这可能与TNF-α和IL-6的生理功能有关㊂TNF-α和IL-6都是参与炎症调控的重要细胞因子,是机体对抗外来病原体入侵时的重要信号分子,但是在效应细胞上有所区别,TNF-α分泌会进一步激活CD4+㊁CD8+T细胞以及Treg细胞,调控细胞免疫过程[35];而IL-6调控B细胞,在体液免疫中具有重要作用[36]㊂因此PS-NPs主要诱导肠道细胞免疫反应㊂Xu等[37]在A549细胞中同样发现70 nm PS-NPs刺激后TNF-α基因表达远高于IL-6,表明纳米塑料在不同组织间的致炎效应存在一致性㊂目前对纳米塑料在动物体内甚至细胞内的动力学分布规律研究较少,且不少研究的结果之间也存在差异㊂一方面可能是由于选用模型生物不同,个体差异性较大,另一方面是由于纳米塑料难以检测,第1期陈煊威等:聚苯乙烯纳米塑料在小鼠组织和细胞水平的累积分布规律及动态毒性响应359㊀目前常用的检测方式是对纳米塑料标记荧光信号,但是荧光技术在应用于动物时容易受到生物自发荧光的干扰,对结果影响较大[38]㊂近年来有研究团队通过对纳米塑料标记金属锆的同位素,解决了荧光信号干扰大的问题,为后续检测纳米塑料的体内分布和转运规律提供新的研究方法[26]㊂通信作者简介:陈瑾(1987 ),女,博士,讲师,主要研究方向为环境微污染毒性预警与健康风险评价㊂参考文献(References):[1]㊀Eriksen M,Lebreton L C,Carson H S,et al.Plastic pollu-tion in the world s oceans:More than5trillion plasticpieces weighing over250,000tons afloat at sea[J].PLoSOne,2014,9(12):e111913[2]㊀Zhang G S,Liu Y F.The distribution of microplastics insoil aggregate fractions in southwestern China[J].TheScience of the Total Environment,2018,642:12-20 [3]㊀Zhang K,Shi H H,Peng J P,et al.Microplastic pollutionin China s inland water systems:A review of findings,methods,characteristics,effects,and management[J].TheScience of the Total Environment,2018,630:1641-1653 [4]㊀Zhang K,Xiong X,Hu H J,et al.Occurrence and 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