404 not found the stability and persistence of urls published in medline

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Cronkhite-Canada综合征三例报道并文献复习

·4210·1420.2018.05.012.WANG Q W，ZHANG T，WEN J G，et al. Analysis of multivariate prognosis of upper urinary tract urothelial carcinoma and risk factors of postoperative bladder cancer［J］. Journal of Clinical Urology，2018，33（5）：385-389. DOI：10.13201/j.issn.1001-1420.2018.05.012.［13］PRICE S J，SHEPHARD E A，STAPLEY S A，et al. Non-visibleversus visible haematuria and bladder cancer risk：a study of electronic records in primary care［J］. Br J Gen Pract，2014，64（626）：e584-589. DOI：10.3399/bjgp14X681409.［14］VIVANTE A，AFEK A，FRENKEL-NIR Y，et al. Persistentasymptomatic isolated microscopic hematuria in Israeli adolescents and young adults and risk for end-stage renal disease［J］. JAMA，2011，306（7）：729-736. DOI：10.1001/jama.2011.1141.［15］MATULEWICZ R S，MEEKS J J. Blood in the urine （hematuria）［J］.JAMA，2016，316（14）：1508. DOI：10.1001/jama.2016.4716.［16］KASHTAN C E，DING J，GAROSI G，et al. Alport syndrome：a unified classification of genetic disorders of collagen IV α345：a position paper of the Alport Syndrome Classification Working Group［J］. Kidney Int，2018，93（5）：1045-1051. DOI：10.1016/j.kint.2017.12.018.［17］NIELSEN M，QASEEM A，High Value Care Task Force of theAmerican College of Physicians. Hematuria as a marker of occult urinary tract cancer：advice for high-value care from the American college of physicians［J］. Ann Intern Med，2016，164（7）：488-497. DOI：10.7326/M15-1496.（收稿日期：2022-02-11；修回日期：2022-05-28）（本文编辑：贾萌萌）·全科医生诊室·Cronkhite-Canada 综合征三例报道并文献复习李淑英1，林颖敏2，王敏1，3*【摘要】　Cronkhite-Canada 综合征（CCS ）目前被认为是一种非遗传性疾病，临床较为罕见，内镜下多表现为胃肠道多发息肉，临床上以消化道症状、皮肤色素沉着、脱发、脱甲等为主要表现。

第八章pubmed 检索方法

(3)著者检索：遵循“姓前名后”原则，姓用全称，名用缩写。如：Smith JR
Smith J@ Yang[AU]
(4)刊名检索：可用期刊名全称，也可用MesH期刊名缩写检索。如：Molecular biology of the cell[ta]
Mol biol cell[ta]
(5)文献类型检索：文献类型标识符[PT]，如欲检索综述文献可使用检索式review[PT]即可。
Internet网络上有三十多个站点提供Free Medline检索服务，如：PubMed, HealthGate， Medscape，Medical Matrix，BioMedNet等。但只有PubMed是官方网站。
/pubmed
三、Pubmed检索系统
Pubmed检索规则：
Pubmed进行字段限定检索时，字段标识符加在检索词之后；字段标识符必须用方括号括起来；大小写以及检索词与方括号之间有无空格无关紧要。
Pubmed处理布尔逻辑表达式是按从左到右的顺序进行的。但可以通过括号来改变运算顺序。如果Pubmed发现检索式中有非限定的词组，它就自动检索该词组，再将该集合与检索式的其它项进行运算。
字段标识符 [AD]：机构、第一作者地址 [ALL]：所有字段 [AU]：作者姓名 [TA]：期刊名 [LA]：语种 [MAJR]：主要概念的医学主题词 [MH]：医学主题词 [PT]：出版类型 [TW]：文本词 [TI]：题名 [DP]: 出版日期
练习题： 1、查肺肿瘤放射疗法，任选题录、文摘、全文各1篇，按Medline格式显示。（lung neoplasms/radiography[mh]） 2、比较brain[tw]和brain的检索结果 3、检索Vitamin h,查验检索词的转换情况 4、比较Smith JR[AU]和Smith JR的检索结果 5、查期刊molecular biology of the cell 上的文章 6、检索肺肿瘤2002年综述文献

Medline中3093种期刊的缩写与全称对照表

Medline中3093种期刊的缩写与全称对照表20 century British history. (20 Century Br Hist)AACN clinical issues. (AACN Clin Issues)AANA journal. (AANA J)AAPS pharmSci [electronic resource]. (AAPS PharmSci)ACP journal club. (ACP J Club)AIDS (London, England) (AIDS)AIDS alert. (Aids Alert)AIDS care. (AIDS Care)AIDS education and prevention : official publication of the International Society for AIDS Education. (AIDS Educ Prev)AIDS patient care and STDs. (AIDS Patient Care STDS)AIDS research and human retroviruses. (AIDS Res Hum Retroviruses)AIHAJ : a journal for the science of occupational and environmental health and safety. (AIHAJ) AJNR. American journal of neuroradiology. (AJNR Am J Neuroradiol)AJS; American journal of sociology. (AJS)ANS. Advances in nursing science. (ANS Adv Nurs Sci)ANZ journal of surgery. (ANZ J Surg)APMIS : acta pathologica, microbiologica, et immunologica Scandinavica. (APMIS)ASHA. (ASHA)Abdominal imaging. (Abdom Imaging)Academic emergency medicine : official journal of the Society for Academic Emergency Medicine. (Acad Emerg Med)Academic medicine : journal of the Association of American Medical Colleges. (Acad Med) Academy of Management journal. Academy of Management. (Acad Manage J)Academy of management review. Academy of Management. (Acad Manage Rev)Accident and emergency nursing. (Accid Emerg Nurs)Accident; analysis and prevention. (Accid Anal Prev)Accounts of chemical research. (Acc Chem Res)Acta anaesthesiologica Scandinavica. (Acta Anaesthesiol Scand)Acta anatomica. (Acta Anat (Basel))Acta astronautica. (Acta Astronaut)Acta biotheoretica. (Acta Biotheor)Acta crystallographica. Section A, Foundations of crystallography. (Acta Crystallogr A)Acta crystallographica. Section B, Structural science. (Acta Crystallogr B)Acta crystallographica. Section C, Crystal structure communications. (Acta Crystallogr C)Acta crystallographica. Section D, Biological crystallography. 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Jpn. J. Clin. Oncol.-2012-Kotake-29-35

Number of Lymph Nodes Retrieved is an Important Determinant of Survival of Patients with Stage II and Stage III Colorectal CancerKenjiro Kotake 1,2,*,Satoshi Honjo 2,Kenichi Sugihara 2,Yojiro Hashiguchi 2,Tomoyuki Kato 2,Susumu Kodaira 2,Tetsuichiro Muto 2and Yasuo Koyama 21Department of Surgery,Tochigi Cancer Center and 2Registry Committee,Japanese Society for Cancer of the Colon and Rectum,Tochigi-ken,Japan*For reprints and all correspondence:Kenjiro Kotake,Department of Surgery,Tochigi Cancer Center,4-9-13Yohnan,Utsunomiya,Tochigi-ken 320-0834,Japan.E-mail:kkotake@tcc.pref.tochigi.lg.jpReceived June 30,2011;accepted October 21,2011Objective:The number of lymph nodes retrieved is recognized to be a prognostic factor of Stage II colorectal cancer.However,the prognostic signiﬁcance of the number of lymph nodes retrieved in Stage III colorectal cancer remains controversial.Methods:The relationship between the number of lymph nodes retrieved and clinical and pathological factors,and signiﬁcance of the number of lymph nodes retrieved for prognosis of Stage II and III colorectal cancer were investigated.A total of 16865patients with T3/T4colo-rectal cancer who had R0resection were analysed.Results:The arithmetic mean of the number of lymph nodes retrieved of all cases was 20.0.The number of lymph nodes retrieved were varied according to several clinical and patho-logical variables with signiﬁcant difference,and the greater difference was observed in scope of nodal dissection.Survival of Stages II and III was signiﬁcantly associated with the number of lymph nodes retrieved.Five-year overall survival of the patients with 9of the number of lymph nodes retrieved and those with .27differed by 6.4%for Stage II colon cancer,8.8%for Stage III colon cancer,12.5%for Stage II rectal cancer and 10.6%for Stage III rectal cancer.With one increase in the number of lymph nodes retrieved,the mortality risk was decreased by 2.1%for Stage II and by 0.8%for Stage III,respectively.The cut-off point of the number of lymph nodes retrieved was not obtained.Conclusions:The number of lymph nodes retrieved was shown to be an important prognos-tic variable not only in Stage II but also in Stage III colorectal cancer,and it was most promin-ently determined by the scope of nodal dissection.A cut-off value for the number of lymph nodes retrieved was not found,and it is necessary to carry out appropriate nodal dissection and examine as many lymph nodes as possible.Key words:colorectal cancer –number of lymph nodes retrieved –lymph node dissectionINTRODUCTIONLymph node metastasis is the most important determinant of survival in localized colorectal cancer (CRC),and it has been used as an indicator for postoperative adjuvant chemo-therapy.In recent years,it has been recognized that in add-ition to lymph node metastasis,the number of lymph nodes retrieved (NLNR)is closely related to prognosis of Stage II CRC (1–4).Some clinical guidelines recommendpostoperative adjuvant chemotherapy in Stage II CRC with a small NLNR to prevent recurrence (5,6).However,the precise mechanism how the NLNR works on prognosis has not been clariﬁed,because the NLNR is thought to be de-pendent on the scope of lymph node dissection,quality of pathologic examination and individual differences in the number of lymph node present.Signiﬁcance of the NLNR in Stage III CRC remains controversial (1,7–10).Clinical#The Author 2011.Published by Oxford University Press.All rights reserved.For Permissions,please email:journals.permissions@Jpn J Clin Oncol 2012;42(1)29–35doi:10.1093/jjco/hyr164Advance Access Publication 18November2011at United Arab Emirates University on May 9, 2014/Downloaded fromevidence on the NLNR should be formulated,also allowing for the fact that laparoscopic surgery has been rapidly spreading in Japan since the late 1990s (11).The aim of this study is not only to investigate the rela-tionship between the NLNR and clinical and pathological factors,but also to clarify signiﬁcance of the NLNR on prog-nosis of Stage II and III CRC,using the database for the Japanese Society for Cancer of the Colon and Rectum (JSCCR),which contains information of a large number of patients with CRC recorded in accordance with the clinical and pathological classiﬁcation of the JSCCR (12).PATIENTS AND METHODSThe JSCCR has a registration system which has started in 1980.The member institutions which are located all over Japan voluntarily have been registering the clinical and pathological information of patients with CRC who were treated in each institute.The database currently contains in-formation about 140000CRC patients treated between 1974and 2002(13).A total of 16865patients who had T3or T4colorectal adenocarcinoma and underwent R0resection accompanied by D2or D3lymph node dissection between 1985and 1994were extracted from the database.Because laparoscopic surgery for CRC was introduced in 1992(11),nearly all the cases in the present study were treated with open surgery.During this period,chemotherapeutic regimens of neither 5-ﬂuorouracil and leucovorin nor oxaliplatin were available in Japan.In colon cancer,D2dissection means removal of peri-colic nodes and intermediate nodes,and D3dissection means removal of main lymph nodes at the root of the re-gional artery in addition to D2dissection.In rectal cancer,D2dissection is removal of both peri-rectal nodes locating in the mesorectum and lymph nodes along the middle rectal artery between the proper rectal fascia and the pelvic nerve plexus,and D3dissection includes removal of the main nodes around the inferior mesenteric artery and lateral nodes dissection which means removal of internal iliac and obtur-ator lymph nodes in addition to D2dissection.The classiﬁ-cation of JSCCR clearly states the scope of dissection (12).Exclusion criteria were as follows:unspeciﬁed age,syn-chronous multiple cancers,no pathologic examination of lymph nodes,unknown followed-up status and receiving perioperative radiotherapy.To eliminate possible data entry errors at the time of registration,patients with 100or more lymph nodes retrieved were also excluded.The correlation between the histologically proven NLNR and the following variables were investigated:year of treat-ment,age,gender,tumour site,histological grade,depth of tumour invasion,degree of lymph node metastasis,tumour size,scope of lymph node dissection,postoperative adjuvant chemotherapy and the number of patients registered per insti-tution.The depth of tumour invasion and degree of lymph node metastasis described by the JSCCR classiﬁcation (12),which is not translated into the UICC-TNM classiﬁcation system,is given in Table 1.S TATISTICAL M ETHODSFirst,the NLNR was investigated in relation to age,gender,tumour site,depth of tumour invasion,stage and other clinic-al and pathological characteristics using multiple linear re-gression with mutual adjustment of these factors to calculate adjusted means due to each level of them (14).Secondly,an association of the NLNR in Stage III with the number of metastasized lymph nodes was investigated by the Kruskal–Wallis test for the categorized NLNR and by the use of Spearman’s correlation coefﬁcient for the NLNR treated as continuous variable.Thirdly,survival analysis was done according to the quartiles of the NLNR for patients with Stages II and III by the Kaplan–Meier methods,and statis-tical signiﬁcance for the difference was tested by log-rank test with length of the follow-up period being truncated at 5years.Fourthly,the Cox proportional hazard model was employed to examine an effect of the NLNR on survival adjusted for other clinical variables in multivariate analyses.Table 1.Classiﬁcation of depth of tumour invasion and lymph node metastasis according to the rules by the JSCCR Depth of tumour invasion a sm Invasion beyond the mucosa but within the submucosa mpInvasion beyond the submucosa but within the proper muscle layerFor further invasion of cancers arising from the intestine covered with the serosa ss Invasion beyond the proper muscle layer but not exposed on the serosal surfacese Invasion exposed on the serosal surface siInvasion to other organs or structuresFor further invasion of cancers arising from the intestine not covered with the serosa a1Invasion beyond the proper muscle layer but penetrating not deeplya2Invasion beyond the proper muscle layer and penetrating deeply ai Invasion to other organs or structures Lymph node metastasisn0No lymph node metastasisn1Metastasis to lymph nodes that are located along the marginal artery and adjacent to the colonn2Metastasis to lymph nodes that are located along the course of the major vessels supplying the arean3Metastasis to lymph nodes that are located around the superior or inferior mesenteric vessels,and/or metastasis to lateral lymph nodes for some cases with rectal cancern4Metastasis to lymph node more distant than that for n3JSCCR,Japanese Society for Cancer of the Colon and Rectum.asm,mp,a group consisting of ss,a1and a2,another group consisting of se,ai and si are corresponding to the UICC pT1,pT2,pT3and pT4,respectively.30Number of lymph nodes retrievedat United Arab Emirates University on May 9, 2014/Downloaded fromDummy variables in the models were assigned to levels of relevant variables other than a reference category of each variable.Interactions between the NLNR and degree of lymph node metastasis (presence or absence),scope of lymph node dissection and tumour site (colon vs.rectum)on the risk for death due to CRC were examined by comparing the full model with the model having also the interaction terms;the likelihood ratio statistics obtained from 22times difference in log-likelihood between the two models was tested as x 2statistics.Because the interaction between the NLNR and the lymph node metastasis was statistically sig-niﬁcant as shown in the latter,the multivariate analysis by the Cox model was performed for the Stage II and III cancers separately.Finally,martingale residuals (15)were computed based on the model including the year of treat-ment,age,gender,depth of tumour invasion,histological grade,tumour site,tumour size,lymph node dissection,post-operative chemotherapy (done vs.not done)and the number of registrations from institution.The residuals were plotted against the NLNR for Stages II and III,separately.All statis-tical analyses were performed using STATA Statistical Software (STATA Corporation,College Station,TX,USA),and P ,0.05was regarded as denoting statistical signiﬁ-cance otherwise speciﬁed.RESULTSFigure 1shows the distribution of the NLNR for 16865patients.A total of 336857lymph nodes were retrieved,with a median of 17.0,an arithmetic mean of 20.0with a standard deviation of 14.0and a mode of 10.Because the NLNR was distributed with the right skewness,a log-transformed value of the NLNR was used in most statistical analyses and the geometric mean was calculated instead of the arithmetic mean in the following section.As shown in Table 2,the NLNR was varied according to categories of selected variables including age,gender,degree of tumour invasion,histological grade,tumour site,tumour size,scope of lymph node dissection,degree of lymph node metastasis and number of registration per insti-tute.The greater difference in the NLNR was observed in scope of lymph node dissection.The NLNR was divided into four subgroups (quartiles): 9,10–16,17–26and 27.The number of metastatic nodes for each subgroup is shown in Table 3.The number of positive lymph nodes was increased with the increasing NLNR.The same was observed in each site.Even when handling the both number as continuous variables,the two were weakly correlated to each other (Spearman’s correlation coefﬁcient ¼0.0813,P ,0.01).Overall survival of Stages II and III was signiﬁcantly asso-ciated with the NLNR.The same results were observed even if it was investigated according to tumour sites (Table 4).When comparison was made between patients with 9of the NLNR and those with 27,the 5-year overall survival differed by 6.4%for Stage II colon cancer,8.8%for Stage III colon cancer,12.5%for Stage II rectal cancer and 10.6%for Stage III rectal cancer.The 5-year disease-speciﬁc survival differed similarly between those with 9of the NLNR and with 27(P ,0.001,data not shown).Scope of the lymph node dissection and tumour site did not inﬂuence the effect of the NLNR on the risk for death (P for interaction ¼0.91and 0.58,respectively,when the NLNR was categorized;and 0.19and 0.84,respectively,when the NLNR was treated as a continuous variable),but lymph node metastasis inﬂuenced the effect of the NLNR (P ,0.01when the NLNR was categorized or treated as con-tinuous).Therefore,the Cox proportional hazard model was employed for the Stage II and III CRC separately examining CRC mortality risk due to the increasing NLNR adjusted for age,sex,scope of the dissection and other factors (Table 5).Stages II and III with 27of the NLNR had the decreased risk by 54and 25%when compared with those with 9,re-spectively.With one increase in the NLNR,CRC mortality risk was decreased by 2.1%for Stage II and by 0.8%for Stage III,respectively.For both Stages II and III,the cut-off point was not obtained because the plots of the martingale residuals were fairly linear (data not shown).DISCUSSIONIn the present study,it was shown that the NLNR was a crit-ical prognosticator for not only Stage II but also Stage III CRC.The arithmetic average of the NLNR in our study was comparable to the reports based on data from single institu-tion (16–18).On the other hand,the NLNR was around 10in the studies that examined large-scale database,such as the NCDB and SEER (2,10,19,20).Theoretically,the NLNR may be inﬂuenced by the extent of surgery or scope of lymph node dissection,technique of pathologic examination and individual difference intheFigure 1.Number of lymph nodes retrieved per patient in 16865colorectal cancer patients using the JSCCR database.JSCCR,Japanese Society for Cancer of the Colon and Rectum.Jpn J Clin Oncol 2012;42(1)31at United Arab Emirates University on May 9, 2014/Downloaded fromTable 2.Adjusted means of the number of lymph nodes retrieved (NLNR)according to clinical and pathological variables Variables Number of cases Adjusted means of NLNR 95%conﬁdence interval P value1985148315.52Reference 1986167815.3614.5916.160.6891987165115.0714.3215.870.2631988167914.7013.9615.480.0391989185815.0514.3215.820.2311990194815.3214.5816.100.6151991164115.3314.5516.140.6361992156316.3015.4717.170.0671993155416.4015.5617.280.0401994181015.7915.0016.610.510Trend0.001Age (years)16–4054220.5219.2421.88,0.00141–54348717.2416.7117.78,0.00155–64549915.54Reference 65–74480514.7214.3115.15,0.00175þ253213.5913.1214.08,0.001Trend,0.001Sex Male 971615.13Reference Female 714915.9215.5716.28,0.001Depth of invasion ss/a1989215.14Reference s/a2606716.0015.6316.39,0.001si/ai 90615.3514.5916.150.600Trend0.001HistologyWell differentiated 841516.00Reference Moderately differentiated 714314.9914.6515.34,0.001Others 130714.6914.0615.35,0.001SiteRight colon 481717.60Reference Left colon 528113.5713.1813.97,0.001Rectum 676715.6015.1716.04,0.001Diameter (mm)10–1915910.859.6912.14,0.00120–2982710.9610.3911.58,0.00130–39221512.6212.1513.11,0.00140–49332414.18Reference 50–59332115.8515.3216.40,0.00160–69249117.2216.6017.87,0.00170–79150118.1017.3318.90,0.00180–8997119.0018.0520.00,0.001Continued32Number of lymph nodes retrievedat United Arab Emirates University on May 9, 2014/Downloaded fromnumber of nodes present.The present study clearly showed that the scope of lymph node dissection affected the NLNR. More lymph nodes are to be harvested for D3than for D2 dissection if the pathological examination technique is con-stant.The NLNR was dependent on factors other than scope of lymph node dissection in the present investigation,and theﬁndings on several factors were comparable with those from previous studies including gender,age,degree of lymph node metastasis,grade of differentiation,tumour site, depth of tumour invasion and size(2,3,9,10,17,19,21).Associations of those factors with the NLNR may be explained as follows:(i)the reported association between the NLNR and lymph node metastasis may be possibly related to the larger size of metastatic nodes than that of non-metastatic ones(19,22),(ii)proliferation of lymph tissue around the ileocecal region and the longer removed bowel may be associated with the larger NLNR for the right than for the left colon and(iii)lateral dissection for rectal cancer should be associated with the increased NLNR.Although we have no direct evidence showing the contribution ofTable2.ContinuedVariables Number of cases Adjusted means of NLNR95%conﬁdence interval P value90–9954219.5518.3220.87,0.001 100–19972919.3018.2020.48,0.001Trend,0.001 Scope of lymph node dissectionD2624412.31ReferenceD3*******.6617.2518.08,0.001 Grade of lymph node metastasisn0914315.00Referencen1461515.9615.5516.38,0.001 n2260116.4315.9016.97,0.001 n350614.6013.6715.600.429Trend,0.001 Reported chemotherapyNo587015.61ReferenceYes1099515.3815.0115.750.219 Number of registrations per institution1–1957512.2611.5013.07,0.001 20–49139714.9314.3115.590.518 50–99337414.7814.3315.250.806 100–199603014.72Reference200þ548917.2716.8117.75,0.001Trend,0.001Table3.Number of lymph node retrieved and that of metastatic lymph nodesNLNR Total Number of metastatic lymph nodes(mean)Right colon Left colon Rectum1–9 2.1 2.2 1.9 2.110–16 2.9 3.2 2.7 2.717–26 3.4 3.9 2.9 3.127þ 4.1 4.8 3.4 3.6 Overall 3.2 3.6 2.65 3.03Table4.Five-year overall survival rates of the patients with Stage II and III colorectal cancer according to the number of lymph nodes retrievedNLNR Stage II Stage IIIColon Rectum Colon Rectum1–981.071.664.253.910–1684.379.468.155.817–2684.682.968.854.827þ87.484.173.064.5Log-rank0.0006,0.00010.0003,0.0001Jpn J Clin Oncol2012;42(1)33at United Arab Emirates University on May 9, 2014/Downloaded frompathological technique to the NLNR (2),it is difﬁcult to ﬁnd other speculation other than differentiated precision of patho-logical examination for the variation in the NLNR by insti-tute (23).It remains unknown why age and gender were related to the NLNR as shown not only in the present but also in other studies (2,3,10).Studies have reported that the NLNR is inﬂuenced also by inﬂammation (21),diverticulum (21)and obesity (19,23,24).In this manner,the NLNR is determined most prominently by the extent of surgery,but is inﬂuenced to some degree by other factors.In the present study,patients with the larger NLNR had a signiﬁcantly better prognosis,and the increased NLNR was associated with decreased risk of death.Furthermore,there was a positive correlation between the NLNR and the number of lymph node metastases (16).When more lymph nodes are examined,the opportunity for discovering a meta-static lymph node is believed to increase and the likelihood of under-staging may decrease.However,the ﬁnding that patients with the larger NLNR may have the better chance for survival,regardless of the number or metastasized nodes,should be more important (10).This cannot be explained based solely on stage migration.Because the present study is retrospective,a residual confounding effect from other related clinical factors should remain after statistical adjust-ment for those.We found no clear statistical evidence for interaction between the scope of lymph node dissection and the NLNR on the risk for death while the NLNR was signiﬁ-cantly larger for D3than for D2.This ﬁnding may explain not only the valid staging but also a possible resection of occult metastasis to lymph nodes is potentially related to im-provement in prognosis.The effects of the NLNR on prognosis,however,cannot be explained based solely on the extent of surgery and pathological examination.The reason for this is that few surgeons would alter the extent of surgery and few patholo-gists would modify examination techniques based on gender,age and histological grade.Thus,a third factor,such as individual differences in lymph nodes as deﬁned by host –tumour relationships,may be considered to be involved.Leibl et al.(21)hypothesized that ‘lymph node neo-formation’established by micro-vessels and peri-capillary lymphocyte accumulation may contribute to indi-vidual variation in the NLNR.Further studies are required to explain the association of individual difference in lymph node and prognosis.For proper assessment of resection and staging,the NLNR is a critical clinical issue to solve.With UICC and AJCC TNM classiﬁcation,based on the recommendation by the Working Party Report to the World Congress of Gastroenterology in 1999(25,26),at least 12lymph nodes should be examined to ensure N0.However,this recommen-dation has few pieces of evidence.Swanson et al.(2)com-mented that 13or more of lymph nodes should be examined to be judged as N0,Wong (17)and Tepper (1)reported 14,Goldstein did 17(16)and Le Voyer et al.(10)did 20.In these studies,no coherent logic leading to the proper NLNR has been established.In the present study,a cut-off value for the NLNR was not determined.This ﬁnding was comparable to a large-scale SEER study (4),as well as a study conducted by individual institution (16).In addition to the NLNR,recent studies demonstrate that a ratio of metastatic lymph node to NLNR (i.e.lymph node ratio)has prognostic signiﬁcance for estimating overall survival for the patients with colon cancer (27–29),although the cut-off value of the ratio remains undetermined.Therefore,at the present,it is required to dissect and examine as many regional lymph nodes as possible for reliable staging.Patients with the small NLNR following proper dissection and pathological examination should be considered at high risk of recurrence.The mainstay of treatment against CRC is surgery.Local control with proper surgery and appropriate adjuvant therapy based on reliable pathological staging are essential.The NLNR may be a potential indicator for postoperative adju-vant therapy.Table 5.Hazard ratio of patients with Stage II and III colorectal cancer according to NLNR analysed by Cox’s proportional model NLNRStage II Stage III Number of casesHazard ratio a 95%CI P valueNumber of cases Hazard ratio 95%CI P value1–92294 1.00Reference 1758 1.00Reference 10–1623330.630.530.76,0.0119490.910.80 1.030.1417–2622900.590.490.72,0.0119690.920.81 1.050.2327þ22260.460.370.57,0.0120460.750.650.86,0.01Trend ,0.01Trend ,0.01Increase by 1node0.9790.9720.985,0.010.9920.9890.996,0.01CI,conﬁdence interval.aHazard ratio of patients with Stage II and III CRC according to NLNR analysed by Cox’s proportional model.34Number of lymph nodes retrievedat United Arab Emirates University on May 9, 2014/Downloaded fromFinally,we should mention the limitations of the study. Since the present study was retrospectively done and infor-mation on cases without follow-up was not used for the ana-lyses,the effect of the NLNR on the survival in the present study is possibly over-or underestimated. CONCLUSIONSIn the present analysis of a database containing information on patients with20lymph nodes retrieved on average,the NLNR was shown to be an important prognostic variable in Stage II and III CRC,especially in patients with Stage III, as well as the number of metastatic nodes.The NLNR was determined most prominently by the scope of lymph node dissection and by other patient’s proﬁle and characteristics of tumour.A cut-off value for the NLNR was not found,and it is necessary to carry out proper dissection and examine as many lymph nodes as possible(4,9).Basic and clinical studies investigating the relation between the varying NLNR across individuals and oncological outcome should be reinforced.FundingJapanese Society for Cancer of the Colon and Rectum. Grant-in-Aid from the Ministry of Health,Labour and Welfare of Japan.Conﬂict of interest statementNone declared.References1.Tepper JE,O’Connell MJ,Niedzwiecki D,Hollis D,Compton C,Benson AB,3rd,et al.Impact of number of nodes retrieved on outcome in patients with rectal cancer.J Clin Oncol2001;19:157–63.2.Swanson RS,Compton CC,Stewart AK,Bland KI.The prognosis ofT3N0colon cancer is dependent on the number of lymph nodes examined.Ann Surg Oncol2003;10:65–71.3.Sarli L,Bader G,Iusco D,Salvemini C,Mauro DD,Mazzeo A,et al.Number of lymph nodes examined and prognosis of TNM stage II colorectal cancer.Eur J Cancer2005;41:272–9.4.Cserni G,Vinh-Hung V,Burzykowski T.Is there a minimum number oflymph nodes that should be histologically assessed for a reliable nodal staging of T3N0M0colorectal carcinomas?J Surg Oncol2002;81: 63–9.5.NCCN Clinical Practice Guidelines in Oncology.Colon Cancer.V.3.2010./professionals/physician_gls/PDF/colon.pdf6.National Cancer Institute.Colon Cancer(PDQ)./cancertopics/pdq/treatment/colon/healthprofessional7.Prandi M,Lionetto R,Bini A,Francioni G,Accarpio G,Anfossi A,et al.Prognostic evaluation of stage B colon cancer patients is improved by an adequate lymphadenectomy:results of a secondary analysis of a large scale adjuvant trial.Ann Surg2002;235:458–63.8.Caplin S,Cerottini JP,Bosman FT,Constanda MT,Givel JC.Forpatients with Dukes’B(TNM Stage II)colorectal carcinoma, examination of six or fewer lymph nodes is related to poor prognosis.Cancer1998;83:666–72.9.Johnson PM,Porter GA,Ricciardi R,Baxter NN.Increasing negativelymph node count is independently associated with improved long-termsurvival in stage IIIB and IIIC colon cancer.J Clin Oncol2006;24:3570–5.10.Le Voyer TE,Sigurdson ER,Hanlon AL,Mayer RJ,Macdonald JS,Catalano PJ,et al.Colon cancer survival is associated with increasingnumber of lymph nodes analyzed:a secondary survey of intergroup trialINT-0089.J Clin Oncol2003;21:2912–9.11.Inomata M,Yasuda K,Shiraishi N,Kitano S.Clinical evidences oflaparoscopic versus open surgery for colorectal cancer.Jpn J ClinOncol2009;39:471–7.12.Japanese Society for Cancer of the Colon and Rectum.JapaneseClassiﬁcation of Colorectal Carcinoma.2nd English edition.Tokyo:Kanehara&Co.,Ltd2009.13.Kotake K,Honjo S,Sugihara K,Kato T,Kodaira S,Takahashi T,et al.Changes in colorectal cancer during a20-year period:an extendedreport from the multi-institutional registry of large bowel cancer,Japan.Dis Colon Rectum2003;46:S32–43.14.Armitage P,Berry G.Statistical Methods in Medical Research.3rd edn.Oxford:Blackwell Science1994.15.Therneau TM,Grambsch PM,Fleming RE.Martingale based residualsfor survival models.Biometrika1990;77:147–60.16.Goldstein NS.Lymph node recoveries from2427pT3colorectalresection specimens spanning45years:recommendations for aminimum number of recovered lymph nodes based on predictiveprobabilities.Am J Surg Pathol2002;26:179–89.17.Wong JH,Johnson DS,Hemmings D,Hsu A,Imai T,Tominaga GT.Assessing the quality of colorectal cancer staging:documenting theprocess in improving the staging of node-negative colorectal cancer.Arch Surg2005;140:881–6;discussion886–7.18.Hashiguchi Y,Hase K,Ueno H,Mochizuki H,Kajiwara Y,Ichikura T,et al.Prognostic signiﬁcance of the number of lymph nodes examinedin colon cancer surgery:clinical application beyond simplemeasurement.Ann Surg2010;251:872–81.19.Baxter NN,Virnig DJ,Rothenberger DA,Morris AM,Jessurun J,Virnig BA.Lymph node evaluation in colorectal cancer patients:apopulation-based study.J Natl Cancer Inst2005;97:219–25.20.Joseph NE,Sigurdson ER,Hanlon AL,Wang H,Mayer RJ,MacDonald JS,et al.Accuracy of determining nodal negativity incolorectal cancer on the basis of the number of nodes retrieved onresection.Ann Surg Oncol2003;10:213–8.21.Leibl S,Tsybrovskyy O,Denk H.How many lymph nodes arenecessary to stage early and advanced adenocarcinoma of the sigmoidcolon and upper rectum?Virchows Arch2003;443:133–8.22.Mo¨nig SP,Baldus SE,Zirbes TK,Schro¨der W,Lindemann DG,Dienes HP,et al.Lymph node size and metastatic inﬁltration in coloncancer.Ann Surg Oncol1999;6:579–81.ler EA,Woosley J,Martin CF,Sandler RS.Hospital-to-hospitalvariation in lymph node detection after colorectal resection.Cancer2004;101:1065–71.24.Go¨ro¨g D,Nagy P,Pe´ter A,Perner F.Inﬂuence of obesity on lymphnode recovery from rectal resection specimens.Pathol Oncol Res2003;9:180–3.pton CC,Fielding LP,Burgart LJ,Conley B,Cooper HS,Hamilton SR,et al.Prognostic factors in colorectal cancer.College ofAmerican Pathologists Consensus Statement1999.Arch Pathol LabMed2000;124:979–94.26.Hammond ME,Fitzgibbons PL,Compton CC,Grignon DJ,Page DL,Fielding LP,et al.College of American Pathologists ConferenceXXXV:solid tumor prognostic factors-which,how and so what?Summary document and recommendations for implementation.CancerCommittee and Conference Participants.Arch Pathol Lab Med2000;124:958–65.27.Mammen JM,James LE,Molloy M,Williams A,Wray CJ,Sussman JJ.The relationship of lymph node dissection and colon cancer survival inthe Veterans Affairs Central Cancer Registry.Am J Surg2007;194:349–54.28.Wang J,Hassett JM,Dayton MT,Kulaylat MN.Lymph node ratio:rolein the staging of node-positive colon cancer.Ann Surg Oncol2008;15:1600–8.29.Chen SL,Steele SR,Eberhardt J,Zhu K,Bilchik A,Stojadinovic A.Lymph node ratio as a quality and prognostic indicator in stage IIIcolon cancer.Ann Surg2011;253:82–7.Jpn J Clin Oncol2012;42(1)35at United Arab Emirates University on May 9, 2014/Downloaded from。

pubmed 文献调研组合检索

pubmed 文献调研组合检索Pubmed是一个由美国国立卫生研究院（NIH）开发的生物医学文献数据库，收录了全球范围内的生物医学文献，包括医学、生物学、生物化学、生理学、药学等领域的文献。

在进行文献调研时，组合检索是一种常用的方法，可以帮助我们更快速、准确地找到所需的文献。

组合检索是指将多个关键词或者检索词组合在一起进行检索，以缩小检索结果的范围，提高检索的准确性。

在使用Pubmed进行文献检索时，我们可以使用以下几种组合检索的方法：1. AND检索：将多个关键词用AND连接起来，表示同时包含这些关键词的文献。

例如，我们想要查找关于“心脏病”和“高血压”的文献，可以使用“heart disease AND hypertension”进行检索。

2. OR检索：将多个关键词用OR连接起来，表示包含其中任意一个关键词的文献。

例如，我们想要查找关于“心脏病”或“高血压”的文献，可以使用“heart disease OR hypertension”进行检索。

3. NOT检索：将一个关键词用NOT连接起来，表示不包含该关键词的文献。

例如，我们想要查找关于“心脏病”的文献，但是不想包含“高血压”的文献，可以使用“heart disease NOT hypertension”进行检索。

4. 括号检索：使用括号可以改变检索词的优先级，使得检索结果更加准确。

例如，我们想要查找关于“心脏病”和（“高血压”或“糖尿病”）的文献，可以使用“heart disease AND (hypertension OR diabetes)”进行检索。

除了以上几种组合检索的方法，我们还可以使用通配符、引号、限定词等方式进行检索，以更加精确地找到所需的文献。

在使用Pubmed进行文献检索时，我们需要注意以下几点：1. 关键词的选择：选择合适的关键词可以帮助我们更快速地找到所需的文献。

关键词应该具有代表性、准确性和广泛性。

2. 检索词的组合：合理地组合检索词可以缩小检索结果的范围，提高检索的准确性。

pubmed检索技巧

1 检索词的类型
（3 ）刊名检索：在检索框中键入刊名简称或 MEDLINE 形式的
简写、ISSN号。例如，“Molecular biology reports”,或“Mol Biol Rep”,然后点击检索，系统将在刊名字段检索，并显示检索结果。（4）日期或日期范围检索：可以在检索框中键入日期和日期范围，然后点击检索，系统会按日期检索，日期输入格式为 YYYY/MM/DD,也可以只输入年代或月份，如2000或2005/12 （ 5 ）检索带文摘的记录：检索的格式为 “ 检索词 and has Abstrat ”。注意 MEDLINE 数据库 1975 年出版的文章没有摘要。（6）布尔逻辑检索：Pubmed系统允许使用布尔逻辑检索，其使用方法和MEDLINE
二 PUBMED检索方法
（一）PubMed简单检索 1 检索词的类型（1）词语（主题）检索：在PubMed主页的检索框中键入英文单词或短语，然后点击检索，PubMed即用其自动转换功能进行检索。（2）著者检索：在检索框中键入著者姓氏全部和名字的首字母缩写，格式为“著者姓、名字（首字母缩写）”，如“Smith JA”,然后点击搜索，系统会自动到著者字段去检索，并显示检索结果。
PUBLISHER SUPPLIED CITATIONS
Publisher Supplied Citations 是出版商直接向 Pubmed 递送的电子记录。每条记录都标有 “Pubmed as supplied by publisher”,该记录一旦被 PreMEDLINE收录，则改为“Pubmed in process”, 经标引后改为“Pubmed indexed for Medline”。出版商提供的所有文献记录， MEDLINE并非每篇记录都收录，若不属于收录范围，记录一直保留“Pubmed as supplied by publisher”

Pubmed基本的检索知识

Pubmed基本的检索知识Pubmed是医学专业常用的数据库，对于医学科研工作至关重要，但是对于Pubmed最基本的检索知识你都了解吗？下面介绍了Pubmed三种检索方式，检验一下你都get到了吗？Pubmed主界面1基本检索引文状态标记值分为：[PubMed-indexed for MEDLINE]、[PubMed-in process]、[PubMed-OLDMEDLINE]、[PubMed – as supplied by publisher]四种状态。

[PubMed-indexed for MEDLINE]：被MEDLINE所收录并被标引MeSH主题词，具有完整的书目题录信息，检索此类文章方法:在检索框输入medline [sb]。

[PubMed-in process]：每天收录由MEDLINE的期刊出版商提供的尚未经过规范化处理的数据，该库中的记录只具有简单的书目信息和文摘、每星期当该库中数据被标引MeSH词、文献类型及其他数据时转入MedLine一次，而被处理前的数据从该数据库中删除。

检索此类文章方法:在检索框输入inprocess [sb]。

[PubMed-OLDMEDLINE]：含1950年至1965年期间发表的200万篇生物医学文献。

OldMedline的记录没有MeSH字段和摘要。

检索此类文章方法:在检索框输入oldmedline [sb] [PubMed –as supplied by publisher]：是由出版商提供的电子文献MEDLINE收录范围的文献，每日被添加到In Process Citation中去，换上[PubMed – in process]的标记，并赋予一个MEDLINE的数据识别号UI；不属于MEDLINE收录范围的文献则只有PubMed数据识别号PMID 而没有MEDLINE UI。

布尔逻辑运算符（检索时需大写）AND可用来表示其所连接的两个检索项的交叉部分，也即交集部分。

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BIOINFORMATICSVol.20no.52004,pages668–672DOI:10.1093/bioinformatics/btg465

404notfound:thestabilityandpersistenceofURLspublishedinMEDLINE

JonathanD.WrenAdvancedCenterforGenomeTechnology,DepartmentofBotanyandMicrobiology,TheUniversityofOklahoma,620ParringtonOvalRm.106,Norman,OK73019,USA

ReceivedonJune18,2003;acceptedonJune25,2003AdvanceAccesspublicationJanuary22,2004

ABSTRACTMotivation:TheadventoftheWorldWideWebhasenabledunprecedentedsupplementationoftraditionaljournalpublica-tions,allowingaccesstoresources,suchasvideo,sound,software,databases,datasetstoolargetopublish,andevensupplementaryinformationanddiscussion.However,unliketraditionalpublications,continuedavailabilityoftheseonlineresourcesisnotguaranteed.Anautomatedsurveywascon-ductedtoquantifythegrowthinUniformResourceLocators(URLs)publishedtodateinMEDLINEabstracts,theircurrentavailabilityanddistributionbyjournal.Results:Of1630uniqueURLsidentiﬁed,formattingand/orspellingerrorsweredetectedwithin201(12%)ofthemaspublished.Aftercorrectionsweremade,asurveyrevealedthat∼63%oftheseURLswereconsistentlyavailable,andanother19%wereavailableintermittently.TherateoffailurewasfarworseforanonymouslogintoFTPsites,withonly12of33sites(36%)responding.Thissurveyalsoshowsthatjournalsvarydisproportionatelyinthenumberofwebcitationspublished,suggestingpolicyimplementationamongafewcouldhaveaprofoundimpactoverall.Outofthe306journalswithaURLpublishedinanabstract,Bioinformaticspublishedthemost(12%oftotal).Availability:URLdatabaseandprogramavailablebyrequest.Contact:Jonathan.Wren@OU.edu

INTRODUCTIONScientistshaveusedtheInternetalmostsinceitsinceptionin1969,butitwasdata-intensiveundertakingssuchastheHumanGenomeProject(HGP)thatspawnedanincreasedrelianceuponitthroughacommunityneedtoshare,analyzeandannotatedata(e.g.seeNowak,1993).TheInternetwasthemostpracticalmediumtoprovidesuchanalyticaltoolsandresourcestothescientiﬁccommunity.Asthecostofcomputerhardwaredropped,connectionsbecamemorewide-spreadandbasiccomputerliteracyincreased,theInternetbecameanincreasinglypopularmediumtoaccessabroadvarietyofscientiﬁcinformationandresources.Thepublica-tionoflinkstoonlineresources,however,isaslightlymorerecentdevelopment.In1994,theﬁrstwebpageUniformFig.1.ThenumberofuniqueURLspublishedinMEDLINE,plottedasafunctionoftime.TheproportionofURLscurrentlyaccessible(asofthissurvey)isbrokendownbyyearanddisplayedasshadingoneachbar.Onlineresourcesareplayinganincreasinglyimportantroleinscientiﬁcresearch,asevidencedbytheirinclusionintheabstract.Notsurprisingly,themorerecentthepublication,themorelikelytheURLisstillactive.Datafrom2003isonlyupuntilApril.ResourceLocator(URL)waspublishedwithinaMEDLINEabstract(Williams,1994),andprecededarapidgrowthintheinclusionofonlineresourcesasbeingofcentralimportancetopublishedresearch.Sincethen,thenumberofabstractscontaininganURLhasincreasedrapidly(Fig.1).From1997to2002theaverageannualincreaseinthenumberoftheseURLswas47%,comparedwithaconsistentaverageannualincreaseof5%inthetotalnumberofMEDLINErecordsoverthesameperiod.Today,theInternethasbecomeavaluable,perhapsindispensable,resourceinconductingscientiﬁcresearch(LawrenceandGiles,1999),notjustbecauseoftheaddedconvenienceofrapidinformationretrievalandsharing,butbecauseitalsoprovidesameansofmakingresourcesavail-ablethattheprintedmediasimplycannot.Informationis

668Bioinformatics20(5)©OxfordUniversityPress2004;allrightsreserved.404notfoundoftengatheredinformsnotamenabletothetraditionalprintedmediaofjournals,suchasvideo,audio,softwareprogramsanddatabaseaccess.Often,dataamenabletotheprintedmediaisstilltoolargetobepublishedinajournal.TheHGPusheredinanenormousamountofsequencedatathatwouldbeimpracticalforotherstocopymanuallyfortheirownuse,baseforbase,evenifprintedinajournal.Thissamedatacouldpotentiallychangeasmoresequencewasgatheredandbasequalitycheckingmethodsimproved.Thistrendofgeneratinglargedatasetspersistsandnowencompassesotherdata-intensiveﬁelds,suchasmicroarrayanalysisandproteo-mics.Theneedtostore,manage,distributeandanalyzesuchinformationhasmovedtheInternetfrombeingofsupple-mentalimportancetoaprimaryresourceformanybiologistsandmedicalpractitioners.Inmanyways,onlineresourcesarepartofanewrevolutioninscientiﬁcresearchthatincreasestheaccessibilityofdata,broadensperspectiveandprovidesaccesstotoolsthataidscientiﬁcresearch.Theseresources,how-ever,alsopresentnewchallengestothetraditionalscientiﬁcpeer-reviewprocessforthepublicationofresearch,sincetheycanchangeincontent.Furthermore,becausetheseonlineresourcescandisappearaltogether,theyalsoprovideauniquechallengeintermsofpreservingourhistoricalscientiﬁcknowledgeandevaluatingnewresourcesastheyarise.AnyexperiencedInternetuserwillhaveencounteredthetraditional‘404notfound’messagereturnedbyawebserverinresponsetoanURLthatisnolongeravailable.Severalstudiestodatehavedealtwiththisgeneralproblemof‘URLdecay’.Koehler,forexampleexaminedboththeaccessib-ilityandcontentof360randomlychosenURLsobtainedfromWebcrawlerover3years.Hefoundthat∼50%ofthemwerestillactiveattheendofthistimeandmosthadchangedincontent(Koehler,1999,2002).Morespeciﬁctothebiomedicalﬁeld,anotherstudyexamined184websitesavailablebetween1998–1999withinformationrelatedtotheherbalremedyOpuntiaandfoundonly76(41%)ofthemwerestillavailablein2002(Veronin,2002).WhileboththesestudiesfoundaveryhighrateofURLdecay,theprimarysourceoftheURLsanalyzedwasobtainedthroughsearchenginesandnotthepeer-reviewedliterature.Web-sites,ingeneral,havearelativelyshortlifespan.Numbersvary,regardingthelifespanoftheaveragewebpage,withoneauthorpublishingrangesfrom44days(Kahle,1997)to75days(http://www.archive.org/sciam_article.html).Optimally,thelifespanofpeer-reviewedresourcesrelatedtoscholarlypursuitswouldbepermanent,butwewouldatleasthopetheirlifespanwouldbesubstantiallylongerthantheaveragewebpage.ItisthereforeimportanttoidentifytowhatextentURLdecayisaprobleminthescientiﬁcliterature.Studiesconcerningtheincreaseandpersistenceofpub-lishedURLshavebeenconductedinotherﬁeldssuchascomputerscienceandlaw,bothofwhichdocumentarapidincreaseinthenumberofURLsreferencedbypapersovertimeandatime-dependantdecayinURLavailability.Spinellis(2003)surveyedthefull-textoftwojournals(Communica-tionsoftheACMandIEEEComputerSociety)over4yearsandfoundthat72%ofURLscontainedwithinwerestillactive.Lawrenceandco-workersconductedalarge-scaleanalysisoftheCiteSeerdatabase(Lawrenceetal.,1999),ﬁndingatime-dependentURLdecaywithavailabilityratesrangingfrom47%(for1994data)to77%(for1999data)(Lawrenceetal.,2001).Inthelegalﬁeld,theURLdecayratewasfoundtobehigherwithinfull-textdocuments,rangingfrom30%availab-ility(1997data)to62%availabilityofpublishedwebsitesin2001(Rumsey,2002).However,trendshaveyettobeestab-lishedforthebiomedicalliteratureascontainedinMEDLINE,andgivenanincreasedrelianceupononlineresourcesinconductingbiomedicalresearchitisimportanttodoso.Theaimofthisreportistoestimatethenumber,growthandcurrentavailabilityofallURLaddressespreviouslypublishedwithinMEDLINEabstracts,aswellasprovidestatisticalestimatesofURLuptimeandcontinuityinthebiomedicalliterature.Abstractswerechosenforthisstudybecausetheyarebothreadilyavailableinelectronicformatandintendedtosummarizethemostimportantaspectsofthepublishedwork.Thus,URLsappearinginabstractsareexpectedtobeofcentralimportancetotheworkasawhole.