History of virus
外研版九年级英语下册同步练习：Module 5 unit2---3同步练习题含答案
Unit 2Ⅰ.用括号中所给单词的适当形式填空1．It is necessary for teenagers to get about eight ________ (hour) sleep a night.2．The flowers require ________(water)．3．________ (keep) fit, you have to do more exercise every day.4．—The plane________ (not arrive) yet.—Yes. It ________ (arrive) in five minutes.5．Parents always expect their children ________ (work) hard.Ⅰ. 用适当的介词填空6．People who were born ________ the nineteenth century need more physical effort to work.7．Don't always sit ________ the sofa! Go out and play with your friends.8．Lily's dress is the same ________ the one I bought last week.9．David got a new computer from his father. Now he often uses it ________ his homework.10．It is necessary ________ teenagers to have enough sleep everyday.Ⅰ. 用方框中所给短语的适当形式填空get off, not just…but…，think about，at the same time, at least 11．________ you ________ he likes country music very much.12．Mark never ________________ other people. So nobody wants to be his friend.13．The bus doesn't go to the train station. I'm afraid you'll have to ________________ at the library and take the A52.14．The doctor said that the boy would have to remain in hospital ________________ 7 days.15．You can ride your bike to school, but remember to be careful ________________．Ⅰ.按要求完成下列各题16．Thanks to your help, we were successful in the competition. (改为同义句)________ ________ your help, we were successful in the competition.17．People believe that happiness is important for our general health. (改为同义句)________ ________ ________ that happiness is important for our general health.18．People often walked for miles every day in the past. (对画线部分提问)________ ________ ________ people often ________ every day in the past?19．Eating too much fast food does harm to your health. (改为同义句)________ ________ ________ to your health ________ ________ too much fast food.20．Teenagers do not need as much sleep as babies. (改为同义句) Babies need ________ ________ ________ teenagers.Ⅰ.单项填空()21.—Has Jane done the washing yet?—You cannot ________ her to do such a thing.A．want B．hope C．expect D．wish()22.—Is ________ hard for you to finish this task?—No. I can deal with it.A．that B．this C．they D．it()23.Ms Zhang helped us to find the hotel.Let's ________ thanks to her.A．speak B．say C．talk D．tell()24.Travelling ________ good health and some money.A．offers B．requiresC．manages D．controls()25.—Do you know the boy________ got the first prize in the talent show?—Of course. He's my new neighbour.A．whose B．whom C．which D．whoⅠ.阅读理解How to fight against COVID19? We choose some books to help you. The books were translated into 13 languages, including Japanese, French and Russian. They are convenient for readers to enjoy.family members to prevent the disease.A Brief History of Viruses for Children (Writer:Changsha Whiteflag Dolphin Children's BookWorkshop)This storybook tells the beginning of the virus, sothe readers can understand the history of the viruseasily. The book sets up a “Ten Questions aboutCOVID19” section, which explains the knowledge ofCOVID19 (including how it spreads), helpingchildren readers to understand the virus basingon(基于) reason and science.()26.All the four books are about ________．A．children's daily activitiesB．ten questions about COVID19C．fighting against COVID19D．love between family members, friends and everyone()27.If you want to know the beginning of the virus, you can read ________．A．Virus, Virus, You Cannot Scare Me!B．A Special Spring FestivalC．Ten Tips to Fight MonstersD．A Brief History of Viruses for Children()28.Which writer hopes children can protect wildlife? A．Mu Xiangzhen.B．Gao Jing.C．Dong Ruihan.D．Changsha Whiteflag Dolphin Children's Book Workshop. ()29.The spread of the virus is mentioned in ________．①Virus, Virus, You Cannot Scare Me!②A Special Spring Festival③Ten Tips to Fight Monsters④A Brief History of Viruses for ChildrenA．①②③ B．①②④C．①③④ D．②③④()30.According to the passage, which one is NOT true? A．The books were translated into many languages.B．Children can do something to protect themselves.C．We can understand the virus basing on reason and science.D．We have won the war against COVID19 completely.Ⅰ.任务型阅读It's important to develop healthy habits in your daily life. The following ways will help you become healthier and keep perfect shape.Eat properly. A healthy diet is very important to everybody. Breakfast is the most important in a day. Doctors suggest that students' breakfast should include fruit, eggs, milk, rice or noodles, because these can offer them necessary energy(能量), help them listen carefully in class and keep them healthy. Eat enough for lunch and little for supper. But remember too much sugar is bad for your teeth and blood.Keep off germs(病菌). Daily tooth cleaning reduces the amount of germs which will spread diseases. Germs in the mouth are likely to enter the blood and cause illness, even heart disease. Even if you are not sick, always remember to cough or sneeze into your arms instead of your hands because hands can spread germs to others when you touch something else. Besides, washing hands is necessary after going to the toilet or before having a meal.Exercise regularly. Regular exercise can improve your moods(情绪) and balance(平衡). What's more, it's good for bones. There are many forms of exercise：walking, running, playing ball games or swimming. You can choose your favourite to practise regularly. You will not only feel energetic but also think better after doing exercise.Stay connected. Having regular communication with friends is the key to reducing(减少) stress. And sharing happiness and sadness, exchanging information with others can also help improve memory. Having a friend or a circle of friends can help you feel good.阅读短文，完成表格。
人教版英语八年级下学期Unit 8随堂练习完整版(含答案)
Unit 8 Have you read Treasure Island yet?Section A教材核心知识精炼一、词汇运用(A)根据汉语或音标提示写出单词1. We can see different kinds of birds on this ____(岛).2. We went to Dalian by ____(船) this summer, and I saw the sea for the first time in my life.3. We deeply believe that 5G ____(技术) can lead us to a better future.4.[2019江苏盐城中考改编]Knowledge is a ____(珍宝), but practice is the key to it.5. Mrs. Green loves gardening, and she has a set of garden ____(工具).6. I'm comfortable speaking ____[frentʃ] now.(B)用所给单词的适当形式填空7.____(hurry) up, or you will miss the early bus.8. Hepburn played a role of a princess in Roman Holiday and it is a ____(classic).9. You can ____ some ____ on the trees so that you won't get lost in the forests. (mark)10. After sailing on the sea for thirty days, it was good to be back on ____(land).二、根据汉语意思完成句子(每空一词)1.这本书棒极了。
WHO新冠疫苗技术线路(英文)
WHO新冠疫苗技术线路(英文)A coordinatedGlobal ResearchRoadmapto respond to theD-19 epidemic and beyondThere is broad consensus on the need for research to focus on actions that can save lives now and to facilitate action so that those affected are promptly diagnosed and receive optimal care; while integrating innovation fully withineach research area.Moreover, there is an imperative to support research priorities in a way that leads to the development of sustainable global research platforms pre-prepared for the next disease Xepidemic; thus, allowing for accelerated research, innovative solutions and R&D of diagnostics, therapeutics and vaccines, as well as their timely and equitable access for thoseat highest risk.4 March 20212021 novel Coronavirus Global research and innovation forum: towards a research roadmapTable of contentsTable of contents _____________________________________________________________________ 2 ABOUT THIS DOCUMENT _______________________________________________________________ 7 GOALS OF THE GLOBAL RESEARCH ROADMAP __________________________________________ 9 PROPOSED STRATEGIC APPROACHES AND CRITICAL ACTIONS___________________________ 11 IMMEDIATE NEXT STEPS TO CONTRIBUTE TO CONTROL THE OUTBREAK_____________________ 13 SELECTED KNOWLEDGE GAPS _________________________________________________________ 14 CROSS-CUTTING RESEARCH PRIORITIES ________________________________________________ 15 SCALING UP RESEARCH AND INNOVATION ACTIONS ___________________________________ 16 TIMELINE FOR IMPLEMENTATION OF SELECTED RESEARCH ACTIONS ______________________ 17 MIDTERM AND LONGTERM PRIORITIES TO CONTRIBUTE TO CONTROL THE OUTBREAK _______ 231. Virus natural history, transmission and diagnostics ______________________________________ 232. Animal and environmental research on the virus origin, and management measures at the human-animal interface__________________________________________________________________ 23 3. Epidemiological studies _______________________________________________________________ 24 4. Clinical management _________________________________________________________________ 24 5. Infection prevention and control, including health care workers’protection ______________ 25 6. Candidate therapeutics R&D __________________________________________________________ 25 7. Candidate vaccines R&D______________________________________________________________ 25 8. Ethics Considerations for Research _____________________________________________________ 26 9. Social Sciences in the Outbreak Response _____________________________________________ 26 OPTIMIZNG FUNDING EFFORTS ________________________________________________________ 27 GOVERNANCE_____________________________________________________________________ _ 28 VIRUS NATURAL HISTORY, TRANSMISSION AND DIAGNOSTICS ___________________________ 31 State of the Art _____________________________________________________________________ _______ 31 Knowledge gaps _____________________________________________________________________ ____ 31Clinical virus detection _____________________________________________________________________ ______ 31 Immunity and immune diagnostics ________________________________________________________________ 32 Tools for infection control _____________________________________________________________________ ____ 32 Engineered solutions to clinical diagnostics ________________________________________________________ 32Ongoing research efforts __________________________________________________________________ 32 22021 novel Coronavirus Global research and innovation forum: towards a research roadmapResearch priorities _____________________________________________________________________ ___ 33Other research priorities _____________________________________________________________________ _____ 34What are the key milestones per research priority? _________________________________________ 34 ANIMAL AND ENVIRONMENTAL RESEARCH ON THE VIRUS ORIGIN, AND MANAGEMENT MEASURES AT THE HUMAN-ANIMAL INTERFACE _________________________________________ 36State of the art _____________________________________________________________________ _______ 36 Knowledge gaps _____________________________________________________________________ ____ 37 Ongoing research efforts __________________________________________________________________ 37 Research priorities _____________________________________________________________________ ___ 38 What are the key milestones per research priority___________________________________________ 40 Essential references_____________________________________________________________________ __ 41 EPIDEMIOLOGICAL STUDIES ___________________________________________________________ 42 State of the Art _____________________________________________________________________ _______ 42 Key epidemiological parameters__________________________________________________________ 42 Transmission dynamics ____________________________________________________________________ 42 Disease severity _____________________________________________________________________ _____ 43 Susceptibility _____________________________________________________________________ ________ 43 Control and mitigation measures __________________________________________________________ 44 Knowledge gaps _____________________________________________________________________ ____ 45Transmission dynamics _____________________________________________________________________ ______ 45 Severity _____________________________________________________________________ ____________________ 45 Susceptibility _____________________________________________________________________ _______________ 45 Control and mitigation measures _________________________________________________________________ 45 Ongoing research efforts __________________________________________________________________ 46 Research priorities _____________________________________________________________________ ___ 47 What are the key milestones per research priority___________________________________________ 49 Essential references_____________________________________________________________________ __ 50 CLINICAL CHARACTERIZATION AND MANAGEMENT____________________________________ 51 State of the art _____________________________________________________________________ _______ 51 Knowledge gaps _____________________________________________________________________ ____ 51Scientific gaps _____________________________________________________________________ ______________ 51 Operational gaps _____________________________________________________________________ ___________ 52Ongoing research efforts __________________________________________________________________ 52 32021 novel Coronavirus Global research and innovation forum: towards a research roadmapResearch priorities _____________________________________________________________________ ___ 53Objective 1: Define the natural history of COVID-19 infection _______________________________________ 53 Objective 2: Determine interventions that improve the clinical oute of COVID-19 infected patients53 Objective 3: Determine optimal clinical practice strategies to improve the processes of care_________ 53 Objective 4: Determine how best to link key research questions with researchers in affected regions who are able to recruit patients _____________________________________________________________________ __ 54 Objective 5: Develop platform(s) to of data collection across trials, and collaborations between trials _____________________________________________________________________ 54What are the research priorities for clinical research for this outbreak and beyond?___________ 55What are the key milestones per research priority___________________________________________ 57Essential references _____________________________________________________________________ __ 59INFECTION PREVENTION AND CONTROL, INCLUDING HEALTH CARE WORKERS’PROTECTION 60State of the art _____________________________________________________________________ _______ 60Knowledge gaps _____________________________________________________________________ ____ 61Modes and duration of transmission _______________________________________________________________ 61 Environmental stability of the virus and effective methods to minimize the role of the environment in transmission _____________________________________________________________________ ________________ 61 Personal protective equipment (PPE) and IPC measures____________________________________________ 61 Isolation, quarantine, and optimal health care pathways __________________________________________ 61 Understanding IPC pliance and perception using behavioural change and social science ______ 61 IPC in the munity setting _____________________________________________________________________ 62Ongoing research efforts __________________________________________________________________ 62 Research priorities _____________________________________________________________________ ___ 62Objective 1: Understand the effectiveness of movement control strategies to prevent secondary transmission in health care and munity settings ________________________________________________ 62 Objective 2: Optimize the effectiveness of PPE and its use in reducing the risk of transmission in health care and munity settings_____________________________________________________________ ________ 62 Objective 3: Minimize the role of the environment in transmission of the COVID-19 virus_______________ 62What are the research priorities for IPC for this outbreak and beyond? _______________________ 62What are the key milestones per research priority___________________________________________ 65Essential references _____________________________________________________________________ __ 66CANDIDATE THERAPEUTICS R&D _______________________________________________________ 67State of the art _____________________________________________________________________ _______ 67Knowledge gaps _____________________________________________________________________ ____ 68Ongoing research efforts __________________________________________________________________ 69 Research priorities _____________________________________________________________________ ___ 69Objective 1: Identification of candidates for clinical evaluation in addition to the ones already prioritised. _____________________________________________________________________ __________________ 6942021 novel Coronavirus Global research and innovation forum: towards a research roadmapObjective 2: Multicentre Master Protocol to evaluate efficacy and safety. ___________________________ 69 Objective 3: Coordinated collaboration to implement clinical trials, for evaluation of safety of therapeutics. _____________________________________________________________________ _______________ 69What are the research priorities for each individual thematic area -for this outbreak and beyond? _____________________________________________________________________ ____________ 70 What are the key milestones per research priority___________________________________________ 72 What are the most important actions to facilitate the successful evaluation and use of any of the investigational medical countermeasures? _________________________________________________ 73 Essential references_____________________________________________________________________ __ 74 CANDIDATE VACCINES R&D __________________________________________________________ 75 State of the art _____________________________________________________________________ _______ 75 Critical knowledge gaps __________________________________________________________________ 75 Key research priorities ____________________________________________________________________ 76 Independent Expert Groups _______________________________________________________________ 77 ETHICS CONSIDERATIONS FOR RESEARCH ______________________________________________ 78 State of the art_____________________________________________________________________ _______ 78 Knowledge gaps _____________________________________________________________________ ____ 79 Research priorities _____________________________________________________________________ ___ 80Objective 1: To enable the identification of key knowledge gaps and research priorities._____________ 80 Objective 2: To formulate a clearly defined research governance framework which enables effective and ethical collaboration between multiple stakeholders, including WHO, the global research munity, subject matter experts, public health officials, funders, and ethicists. ____________________ 80 Objective 3: To facilitate effective cross-working and collaboration across the research thematic areas._____________________________________________________________________ ________内容过长，仅展示部分文字预览，全文请查看图片预览。
2020年山东省各地市中考英语试卷附答案解析版
毕业学校姓名准考证号绝密★启用前在2020 年山东省滨州市初中学业水平考试英 语温馨提示:此1. 本试卷分第Ⅰ卷和第Ⅱ卷两部分，共 18 页。
满分 150 分。
考试用时 120 分钟。
考试结束后，将试题卷和答题卡一并交回。
2. 答卷前，考生务必用 0.5 毫米黑色签字笔将自己的姓名、准考证号、座号填写在试卷 题卷和答题卡规定的位置上。
3. 第Ⅰ卷每小题选出答案后，用 2B 铅笔把答题卡上对应题目的答案标号涂黑；如需改动，用橡皮擦干净后，再选涂其他答案标号。
答案不能答在试题卷上。
4. 第Ⅱ卷必须用 0.5 毫米黑色签字笔作答，答案必须写在答题卡各题目指定区域内上相应的位置，不能写在试题卷上；如需改动，先划掉原来的答案，然后再写上新的答案；不准使用涂改液、胶带纸、修正带。
不按以上要求作答的答案无效。
第I 卷（选择题 共 100 分）答一、听力选择（共 20 小题，计 30 分。
每小题约有 8 秒钟的答题时间。
）（一）录音中有五个句子，听句子两遍后，从每小题 A 、B 、C 三个选项中选出能对每个句子做出适当反应的答语。
1. A. Yes, I am. B. No, I can’t. C. Yes, I do.题2. A. You are welcome. B. It doesn’t matter. C. Sure, it’s over there.3. A. Four kilos. B. Three dollars. C. Five hours.4. A. Much better.B. Never mind.C. Sorry to hear that. 无5. A. I can play the guitar.B. I like country music.C. My favorite singer is Jack.（二）录音中有五组对话和五个问题，听对话和问题两遍后，从每小题A 、B 、C 三个选项中选出能回答所给问题的正确答案。
病毒学病毒进化
AIDS, West Nile virus in US, SARS and Influenza virus (H7N9) in China, HCV, HBV, Ebola, MERS-CoV, Zika virus ……,
• Regular bouts every year with influenza and common cold virus
• If 109 viral particles produced in a person per day, then 108 mutant progeny are being produced in that one individual each day of infection!
• The replication error rate for HIV is such that each newly synthesized HIV genome carries on average approximately one mutation.
DNA viruses
• Usually use their host’s enzymes to replicate their DNA so they usually have mutation rates that are more similar to their hosts；However in cases where they do use their own enzymes their mutation rates are often 20 to 100 times greater than that of their hosts.
• Quasispecies and virulence/attenuation
virus
WHERE WE STAND IN 2001: PREVENTING • CONTROLING • CURING VIRAL DISEASES
Viral diseases have played a major role in human history over whatever time scale we choose to explore:
Over the past 1000 years: Smallpox and measles were brought to North and South America by early European explorers/conquerers. These diseases, for which the native American populations had no acquired partial immunity, killed large fractions of the populations, and were a major factor in the decimation of these societies. Over the past 100 years: A newly emerged strain of influenza killed 20 million people in 1918-1919 in the immediate aftermath of World War I. A decade later, polio became one of the most feared infections of children and young adults (including Franklin D. Roosevelt, the U.S. President throughout the Depression and World War II). As the century entered its final 20 years, a new ~100% lethal virus, HIV, spread rapidly around the world via body fluid transmission.
艾滋病的进化史(英文)
Natural history of HIV/AIDS Penny LewthwaiteEd WilkinsAIDS was first recognized in 1981 and is caused by HIV-1. HIV-2 causes a similar illness, but is less aggressive and restricted mainly to West Africa. Continuous high-level HIV replication leads to virus-mediated and immune-mediated destruction of the key immune effector cell, the CD4 lymphocyte. T wo decades of study of the pandemic have provided a wealth of information about the natural history of HIV, leading to the development of highly active antiretroviral therapy (HAART), which has radically improved the prognosis.HIV-1 and HIV-2 – HIV-1 can be divided into different groups (M, O and N) and genetic subtypes. Group M strains account for the HIV epidemic and have 11 subtypes (A–K). Each of these tends to be associated with a particular geographical area, with less strong associations with transmission categories and resistance patterns. Subtype B is most prevalent in the Americas, Japan, Australia, the Caribbean and Europe. HIV-2 infection differs from HIV-1 in that patients have lower viral loads, slower CD4 decline, lower rates of vertical transmission and slower progression to AIDS (12-fold lower). It is important to distinguish between HIV-1 and HIV-2, because HIV-2 is inherently resistant to non-nucleoside reverse transcriptase inhibitors (NNRTIs).EpidemiologyHIV affects 40 million individuals worldwide, with 4.9 million new cases and 3.1 million deaths estimated by the WHO in 2004. Sub-Saharan Africa has the greatest burden of disease, with an estimated 26 million infected individuals. In Southern African countries, 25–40% of adults are infected; the prevalence is 5–15% in most other Sub-Saharan countries. South Africa now accounts for one-third of deaths worldwide. In the UK, 6600 new cases were reported to the Health Protection Agency in 2003; the prevalence was estimated at 53,000, using population estimates and anonymous linked testing.Worldwide, the major route of transmission (> 75%) is hetero-sexual. About 5–10% of new HIV infections are in children and Penny Lewthwaite is Specialist Registrar in Infectious Diseases, TropicalMedicine and General Internal Medicine at North Manchester GeneralHospital, Manchester, UK. Conflict of interests: none declared.Ed Wilkins is Consultant in and Clinical Director of Infectious Diseasesat North Manchester General Hospital, Manchester, UK. His research interests include the toxicity of HIV antiretroviral drugs, hepatitisco-infection, and the investigation of treatment strategies. Conflict of interests: none declared.more than 90% of these are infected during pregnancy, birth or breast-feeding. Most of these cases occur in Africa, the Caribbean or South East Asia, but heterosexual transmission is also the most common mode of transmission in industrialized nations; racial and ethnic minorities represent an increasing proportion of cases. The incidence in injecting drug-users varies widely between countries. It is relatively low in the UK (< 1%), but may be up to 50% in other areas (e.g. Eastern Europe, Vietnam, north-east India, China). Natural historyInfectionHIV can be transmitted through blood, bodily fluids, sexual contact or breast milk. About 4–6 weeks after infection, the individual starts to develop antibodies to HIV. At an earlier stage, HIV is detectable in the plasma by nucleic amplification or p24 antigen. Most infected individuals seroconvert by 3 months and are HIV antibody positive; rarely, this takes up to 6 months.With the advent of antiretroviral drugs, the prognosis has changed dramatically; there is a potential for normal or near-normal life expectancy, particularly when the diagnosis is made before HIV-related complications occur. The prognosis is less good in those presenting later, with a CD4 count of less than 200/µl, but is improving as knowledge of the disease increases and drug therapies improve. In 10–15% of cases, however, drug-resistant HIV is transmitted, and occasional strains are resistant to all three major classes of antiretroviral drugs. In many cases, resistant virus has a lower replication capacity than wild-type virus, but certain factors can reverse this.SeroconversionSeroconversion illness occurs in 40–90% of infected individuals as a consequence of high levels of circulating HIV-1 and the immune system response (Figure 1). The most common symptoms are fever (80%), malaise (68%), arthralgia (54%), maculopapular rash (51%), myalgia, oral ulcers and pharyngitis. Most symptoms resolve after 7–10 days. In a few patients, the illness is more 1severe and may be associated with an opportunistic infection (e.g. pneumocystis pneumonia, oesophageal candidiasis) as the CD4 count transiently declines below 200/µl. Neurological problems such as Guillain–Barré syndrome and Bell’s palsy may occur at this stage. Those with more severe symptoms are more likely to undergo rapid disease progression.Asymptomatic disease (Centers for Disease Control (CDC) category A disease)After seroconversion, the CD4 count usually increases again, but usually to a level below normal. Patients with CD4 counts of 350–800/µl are usually well. The viral load stabilizes at a set-point. The time before late-stage disease or AIDS develops varies.• In some individuals, CD4 count declines rapidly over the fol-lowing 6–12 months. This usually indicates that the viral strain is using the CXCR4 rather than the CCR5 receptor.• In most cases, CD4 count declines slowly over 6–8 years.• In 5–10% of individuals (termed ‘long-term non-progressors’), CD4 count remains stable and viral load relatively low for many years or even decades. In a few cases, viral or host factors explain the slow progression; in most, however, the cause is unknown.Infected individuals may be completely asymptomatic or may have persistent generalized lymphadenopathy (defined as enlarged glands at two or more extra-inguinal sites). This is usually sym-metrical, affecting cervical, axillary and inguinal nodes, but is usually mild and may not be noticed by the individual.CD4 count 200–350/µl (CDC category B disease)Without therapy, the CD4 count eventually declines. At a count of 350/µl, the individual becomes increasingly susceptible to pathogens such as Mycobacterium tuberculosis, Streptococcus pneumoniae and varicella-zoster virus (Figure 2). In a young patient, shingles is a sensitive marker of HIV infection.T uberculosis (TB) is a particular hazard in patients with HIV infection, who are at greater risk of:• reactivation of latent infection (7–10% annual risk, compared with 5–10% lifetime risk in HIV-uninfected individuals)• acquiring TB from a contact (10–20%, compared with 5–10%)• developing progressive primary disease (30–40%, compared with 5–10%)• developing disseminated, miliary or extrapulmonary disease (> 60%, compared with < 25%).Patients are also at risk of second episodes of TB from exogenous infection, as demonstrated by isolate typing.The risk of TB depends on its prevalence in the community and whether the individual is latently infected with M. tuberculosis. Any HIV patient with symptoms of cough, weight loss and night sweats should be investigated for TB; radiological appearances may be atypical with advancing immunosuppression. Treatment is as in HIV-negative patients, with quadruple initial therapy followed by rifampicin and isoniazid, completed in 6 months in total.Pneumococcal pneumonia can occur at any CD4 count and is more often bacteraemic and recurrent.Recurrent oral and vaginal candidiasis invariably becomes a problem as the CD4 count approaches 200/µl. The finding of oral candidiasis without a history of inhaled corticosteroid use or antibiotics should suggest a diagnosis of HIV. First-line treatment is fluconazole.Oral hairy leucoplakia may occur; this appears as white cor-rugations on the side of the tongue and is caused by Epstein–Barr virus. It is usually asymptomatic and highly suggestive of HIV infection. Treatment is seldom required.CD4 count < 200/µl (CDC category C disease)As the CD4 count continues to decline, opportunistic infections and HIV-related tumours may develop (Figure 2).Pneumocystis jirovecii (formerly known as P. carinii) pneu-monia (Figure 3) commonly presents in patients with a CD4 count of less than 200/µl. Before the advent of HAART, it caused significant mortality; this was reduced only by the introduction of primary prophylaxis in those with CD4 counts of less than 200/µl. Patients usually present with a 2–3-week history of dry cough, fever and disproportionate breathlessness. Co-trimoxazole is the agent of choice for prophylaxis and treatment. Alternative treatments include parenteral pentamidine, or clindamycin and primaquine; corticosteroids should be given for moderate-to-severe disease. Cerebral toxoplasmosis – in more than 90% of cases, cerebral toxoplasmosis is caused by reactivation of latent infection. Patients present with a 2–3-week history of fever, headache and seizures, with localizing signs on examination. Multiple ring-enhancingFeatures of HIV infection with declining CD4 countCD4 count 200–350/µl • Pulmonary tuberculosis • Herpes zoster• Oropharyngeal candidiasis • Oral hairy leucoplakia • Salmonellosis • Kaposi’s sarcoma• HIV-associated idiopathic thrombocytopenic purpura • Cervical intraepithelial neoplasia II–III • Lymphoid interstitial pneumonitis CD4 count < 200/µl• Pneumocystis jirovecii pneumonia • Mucocutaneous herpes simplex • Cryptosporidium infection • Microsporidium infection • Oesophageal candidiasis• Miliary/extrapulmonary tuberculosis • HIV-associated wasting • Peripheral neuropathyCD4 count < 100/µl• Cerebral toxoplasmosis • Cryptococcal meningitis • Primary CNS lymphoma • Non-Hodgkin’s lymphoma • HIV-associated dementia• Progressive multifocal leucoencephalopathy• Cytomegalovirus retinitis/gastrointestinal disease • Disseminated Mycobacterium avium intracellulare2lesions are identified on CT or MRI. The absence of IgG antibodies is suggestive of an alternative cause. First-line therapy is with sulfa-diazine and pyrimethamine. Cerebral toxoplasmosis is prevented by co-trimoxazole prophylaxis, and those who are seronegative should be advised not to handle cat litter or eat undercooked meat.Kaposi’s sarcoma (Figure 4) is the most common malignancy associated with HIV . It is caused by human herpesvirus 8. Patients present with discrete, non-pruritic, non-tender, pink-purple papules that are often arranged symmetrically and develop on crease lines. Significant oedema from lymphatic involvement can occur and may precede the cutaneous lesions. The disease may be indolent or fulminant, with rapid visceral involvement and clinical deteri-oration; this is more likely at lower CD4 counts. Visceral disease can occur systemically in the lungs, the gastrointestinal tract and the lymphoreticular system. Palatal Kaposi’s is strongly sugges-tive of systemic disease. HAART and local therapy (radiotherapy or intralesional chemotherapy) is often curative in limited or localized cutaneous disease. In systemic disease, chemotherapy with liposomal doxorubicin or paclitaxel is required in addition to HAART.Oesophageal candidiasis causing pain and difficulty on swal-lowing can be a problem at this stage. Treatment is with flucon-3Chest radiograph in pneumocystis pneumonia.4Kaposi’s sarcoma.azole. In patients who fail to respond, alternative diagnoses such as cytomegalovirus and herpes simplex oesophagitis should be considered.Diarrhoeal disease occurs at all stages of HIV infection and can be causd by various pathogens. Cryptosporidium parvum is a zoonotic intestinal parasite causing self-limiting diarrhoeal illness in HIV-negative patients and in those with CD4 counts of more than 200/µl. Chronic diarrhoea leading to weight loss and malabsorption may occur in patients with significant immunodeficiency. Microsporidium causes a less severe but similar illness. T ogether, these two organisms account for about 20% of cases of diarrhoea. Resolution is best achieved with HAART and reconstitution of the immune system to a CD4 count of more than 200/µl. Cytomegalovirus may affect the whole bowel, but most commonly causes inflammatory colitis associated with bloody diarrhoea.CD4 count < 100/µl (Figure 2)Disseminated Mycobacterium avium intracellulare infection may be a problem as the CD4 count declines. Presentation is with fevers, weight loss, hepatosplenomegaly and anaemia. The diagnosis is usually made on mycobacterial blood culture, and treatment is with four agents (usually rifabutin, azithromycin, ethambutol and ciprofloxacin) for a prolonged period. On completing therapy, if the CD4 count remains less than 100/µl, secondary prophylaxis with weekly azithromycin should be used. Once HAART is initi-ated and the CD4 count reaches 100/µl, secondary prophylaxis can be stopped.Systemic fungal infection may occur in those with advanced disease. In the UK, the most common is Cryptococcus neoformans, which usually causes meningitis but can cause skin lesions and pneumonia. In patients from South East Asia, Penicillium marneffei is the second most common AIDS-defining diagnosis, whereas in those from the Southern USA and South America disseminated infection with Histoplasma capsulatum may occur.Cytomegalovirus infection often represents reactivation of latent disease. It has various presentations; retinitis and colitis are most common. Diagnosis involves histology (showing the charac-teristic owl’s-eye inclusion bodies), viral culture, IgM serology orpolymerase chain reaction analysis. Treatment is with intravenous ganciclovir, cidofovir or oral valganciclovir.Neurological problems at CD4 counts of less than 100/µl include progressive multifocal leucoencephalopathy caused by JC virus, primary CNS lymphoma, and HIV encephalopathy leading to AIDS dementia.High-grade B cell non-Hodgkin’s lymphoma is 100 times more common in HIV-infected individuals than in the non-infected population. It is most common in those with CD4 counts of less than 100/µl and more likely to present with extranodal disease. There are several histological types. Treatment is with systemic chemotherapy.Highly active antiretroviral therapyHAART with three or more drugs has improved life expectancy and prognosis in patients with HIV infection. Since its introduc-tion, there has been an 80% decrease in mortality in industrialized nations. There are three major classes of drugs – nucleoside reverse transcriptase inhibitors (NRTIs), NNRTIs and protease inhibitors. HAART usually comprises two NRTIs combined with one NNRTI or one ritonavir-boosted protease inhibitor. All of these agents have side-effects, including an increased risk of cardiovascular disease. As a result, lifestyle factors such as nutrition, smoking, immunizations, exercise, diet and sleep are becoming increasingly important.LipodystrophyLipodystrophy is estimated to occur in 30–50% of HIV-infected patients. Clinical features include loss of subcutaneous fat (lipoatrophy) from the face (Figure 5) and limbs, and increased fat deposition in the trunk (central obesity). The cause is multi-factorial, with contributions from HIV, genetic factors and anti-HIV drugs, particularly protease inhibitors. Mitochondrial toxicity (mainly NRTI-related) and insulin resistance (mainly protease inhibitor-related) are the two most important under-lying events. Lipid abnormalities include hypertriglyceridaemia, hypercholesterolaemia, increased free fatty acids and reduced high-density lipoprotein. AIDS-defining conditions•Oesophageal candidiasis•Cryptococcal meningitis•Chronic cryptosporidial diarrhoea•Cytomegalovirus retinitis•Chronic mucocutaneous herpes simplex•Disseminated Mycobacterium avium intracellulare•Miliary or extrapulmonary tuberculosis•Pneumocystis jirovecii pneumonia•Progressive multifocal leucoencephalopthy•Recurrent non-typhi Salmonella septicaemia•Cerebral toxoplasmosis•Kaposi’s sarcoma•Non-Hodgkin’s lymphoma•Primary cerebral lymphoma•HIV-associated wasting•HIV-associated dementia5Facial lipoatrophy.。
2022年广东省佛山市南海区九江镇初级中学中考二模英语试题
2022年广东省佛山市南海区九江镇初级中学中考二模英语试题学校:___________姓名：___________班级：___________考号：___________一、语法选择My grandpa loves playing chess. Every day he plays chess with his friends. Last week, he came to visit us in the city. But he was very disappointed when he found nobody here___1___ play chess with him.One day, ___2___ I came back from school, I found my grandpa sitting quietly in his room, doing nothing. I knew he was lonely. “Why not advise him ___3___ online chess on the computer?” I thought.“Grandpa, someone ___4___ for you to play chess.” I said to him. ___5___ his eyes wide open, he said, “Really? Who? And where?”I took him to ___6___ computer in my room and said, “Right here.” Then I taught him how to use the Internet and how to play chess online. At first, he was slow. Having tried several times, he became better and began to play chess with people from around the world.“___7___ interesting it is! This is simply fantastic!” he cried excitedly. Now my grandpa is quite good at playing chess online and ___8___ a lot of friends on the Internet at the same time. And he is much ___9___ than before. Grandpa ____10____ back home soon. But I believe the time when we played chess online was so great that both of us will never forget. 1．A．can B．should C．could D．must 2．A．when B．if C．unless D．while 3．A．play B．playing C．to play D．played 4．A．waits B．will wait C．has waited D．is waiting 5．A．For B．In C．With D．Without 6．A．a B．an C．the D．/ 7．A．How B．How a C．What D．What a 8．A．will make B．makes C．has made D．was making 9．A．happy B．happier C．happiest D．the happiest 10．A．goes B．will go C．went D．is going二、完形填空Everyone has only one life, all of us want to do something __11__ to prove the value of life. But sometimes that really needs more courage（勇气）.You have probably never heard of Fan Jinshi. She is a very great woman who I admire a lot. She is a thin woman from the south of China. She is always __12__ in historical culture and ancient art. She __13__ from Peking University. She could find a good job in a big city. Also, she could choose to teach in her university. However, she __14__ all the good conditions and made a brave __15__ to work in Dunhuang, Gansu Province. It’s very dry and short of water there. __16__ it is always windy and sandy all year round. And she couldn’t__17__ delicious food or wear nice clothes. She just did one thing that she must fight against the terrible environment there every day. But she didn’t care. She stuck to __18__ in the desert place and made an effort to contribute（奉献）her youth. What a strong woman fighter she is! I will never forget __19__ she said, “I love my work and I also love every area of my motherland forever. ” Just as Dong Qing said, “__20__ is that you still love your life after seeing the truth clearly. ”11．A．colorful B．beautiful C．awful D．meaningful 12．A．fond B．bored C．interested D．surprised 13．A．learned B．graduated C．taught D．studied 14．A．made up B．gave up C．took up D．put up 15．A．decision B．thought C．try D．action 16．A．However B．Suddenly C．Besides D．Luckily 17．A．enjoy B．produce C．invent D．buy 18．A．travelling B．staying C．studying D．teaching 19．A．where B．when C．how D．what 20．A．Confidence B．Love C．Courage D．Success三、阅读单选We choose one useful books to help you to fight against COVID-19. The books were translated into 13 languages, including Japanese, French and Russian. They are convenientfor readers to enjoy.21．All the lour books are about ________.A．children’s daily activities B．ten questions about COVID-19C．fighting against COVID-19D．love between family members, friends and everyone22．If you want to know the beginning of the virus, you can read ________.A．A special Spring Festival B．Virus, Virus, You Cannot Scare Me! C．A Brief History of Viruses for Children D．Ten Tips to Fight Monsters 23．Which writer hopes children can protect wild life?A．Gao Jing.B．Mu Xiangzhen.C．Dong Ruihan.D．Changsha White-flag Dolphin Children's Book Workshop.24．The underlined word “disease” probably means ________ in Chinese in this passage. A．疾病B．疫情C．灾难D．病毒25．Which of the following is NOT true?A．Children can do something to protect themselves.B．The books were translated into many languages.C．We can understand the virus basing on reason and science.D．We have won the war against COVID-19 completely.Smart home technology doesn’t just mean using apps and automation (自动化). For example, you can now be sitting at the office and simply tell your smart home to turn on the lamps at sunset, or wake up and order the curtains to rise as you do. But things that support voice demands aren’t just for young people, either.The Puleyuan Nursing Home (普乐园敬老院) in South Beijing is a good example. All the electronic devices in the rooms are controlled by smart speaker Tmall Genie (天猫精灵).The machine, developed by Alibaba, started as a speaker that can play whatever music or audio programs when it was asked to play.Rooms equipped with it can detect human presence, as well as temperature, which ensure the safety of the environment for the people. At night, it can also sense (检测)wake-up movements and automatically turn on the lights.Besides, the idea of a voice-controlled home will make nursing homes an even more attractive choice for the elderly, and they are totally affordable. A Tmall Genie costs 499 yuan and other sensors are around 100 yuan. People don’t have to pay extra for these services.More than one million Chinese families are using Tmall Genie. China will have 400million people aged 60 or more before 2033. A Tmall Genie makes it easier to look after the elderly.26．From the passage, we know that Tmall Genie is used in ________.A．a school in Beijing B．a factory in BeijingC．a nursing home D．young people’s home27．The speaker in the passage that can play music or audio programs is developed by________.A．Alibaba B．Baidu C．Puleyuan D．Tmall Genie 28．The underlined word “affordable” means ________ in Chinese.A．昂贵的B．负担得起的C．方便的D．自动化的29．If you want to get the services like those in the Puleyuan Nursing Home, you should pay ________.A．100 yuan B．399 yuan C．49 yuan D．599 yuan 30．The passage mainly talks about ________.A．the smart home technology B．the life of the old people in Beijing C．a nursing home in Beijing D．the introduction of Tmall Genie四、阅读匹配五、短文语境提示填空请用适当的词完成下面的短文，并把所缺单词填写在答题卡指定的位置上，每个空只能填写一个形式正确、意义相符的单词。
药物化学中抗病毒药物
历史回眸： 鼠疫、天花、流感 …人类与瘟疫的较量
“黑死病”曾导致欧洲1/3~1/2的人口死亡，病原体是耶尔 森杆菌，传播途径是由跳蚤把病菌从老鼠传播给人；鼠疫 杆菌袭击淋巴腺导致的腺鼠疫。 天花成了殖民者的秘密武器，在天花的肆虐下，几个原先 有数百万人口的主要印第安部落减少到只剩数千人或完全 灭绝。天花是感染天花病毒引起的，是第一种、也是至今 惟一一种被消灭的传染病。 历史上死亡人数最多的一次瘟疫是流感。1918年，一场致 命的流感席卷全球，造成了2000万到5000万人死亡。
-Transmitted through the
respiratory, gastrointestinal and genital tracts, and the skin, urine, blood, and placenta.
Viruses
• Size: 0.02 ~ 0.4 mm • Consist of a nucleic acid core --- DNA --- RNA • Capsid（病毒壳体）+ Protein Coat ---> Nucleocapsid • Envelope composed of glycoproteins that are viral antigens • Complete package is known as VIRION
Virus Group
Species
Lymphocytic choriomeningitis virus Lassa fever virus Influenza A,B and C viruses Parainfluenza virus Respiratory syncytial virus（呼吸合胞体病 毒）, Measles (rubeola)
吉林省长春市省第二实验(高新、远洋)学校2021-2022学年八年级下学期期中英语试题(五四学制)
吉林省长春市省第二实验（高新、远洋）学校2021-2022学年八年级下学期期中英语试题（五四学制）学校:___________姓名：___________班级：___________考号：___________一、单项选择1．My cousin is such ________ honest man that all of us like him very much.A．a B．an C．the D．/2．—_________ have you lived in the countryside?—Since five years ago.A．How soon B．How much C．How often D．How long 3．—Where is Lucy? I haven’t seen her for days.—She ________ Chengdu. She’ll be back next week.A．has gone to B．has been to C．have gone to D．have been to 4．—Are you looking for your car?—Yes, I am. I parked my car ________ in this area, but now I can’t find it. A．somewhere B．anywhere C．nowhere D．everywhere 5．My sister wants to save some money ________ she can buy her favorite schoolbag. A．unless B．until C．so that D．as soon as 6．The basketball game was wonderful yesterday, ________ the 3 points at the last minute. A．probably B．recently C．mostly D．especially 7．—Are you interested in the ending of the movie?—I have to say “No”, because she ________ me the story.A．tells B．will tell C．has told D．is telling 8．—Do you know The Three-Body Problem will soon be made into an English-language TV show?—Fantastic. I’m sure it will be very popular ________ young people.A．among B．opposite C．between D．through 9．—The songs the little girl sings are very sweet.—She ________ a good voice. Nobody taught her.A．takes care of B．is similar to C．looks forward to D．is born with 10．—Could you please tell me the meaning of the word “attention”?—Sorry, I don’t know, either. Why not ________ in the dictionary?A．give it up B．lay it out C．hand it out D．look it up 11．Mr. Wang is very friendly to us. He is__________ of all the persons I know. A．patient B．less patientC．more patient D．the most patient :12．—________rapid progress our country is making in science and technology!—So it is. We are enjoying the convenience of modern technology.A．What B．How C．What a D．How a 13．________ the reading speed, we should pay attention to the key words, not read word by word.A．To increase B．Increase C．Increasing D．Increased 14．I have some tickets for the football match. I called my friends to see___________. A．where did they buy them B．why they liked to go thereC．when did we go together D．whether they’d like to go15．—I haven’t seen the play Teahouse.—________. Shall we go and see it this weekend?A．Yes, please B．No, thanks C．Me neither D．Me too二、补全对话6选5根据对话内容，运用文后所给的句子选项补全对话，选项中有一项是多余的。
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• 1988 The ARPANET worm, written by Robert Morris, disables approx 6,000 computers on the network. “ I remember when it happened. It was a big deal to computer people like me, but in 1988 the Internet was unknown even to the most sophisticated media reporters, and the World Wide Web had not been invented yet. I remember the NBC Evening News devoting less than 30 seconds to the topic. If an equally severe disruption of the Internet were to happen today, the President of the United States would probably hold a press conference to calm the nation.” Donn Seeley
8
“It has raised the public awareness to a considerable degree.” [Robert H Morris, quoted in the New York Times 11/5/88]
9
Trojan Horse Virus
Any program with a hidden intent. Disguise: useful program
Fred Cohen given credit for the word “VIRUS” being applied to an unwanted piece of code
5
1986 “Brain” - the first IBM PC Computer Virus The Pakistani virus
The history of virus
1
1981 Elk Cloner
First Virus when?
2
1981 Elk Cloner - First Virus – Apple II
Boot Sector Virus Spread on Apple II floppy disks (which contained the operating system)
3
Elk Cloner 1981, Apple II
Cloner stayed in the computer if it was not turned off, continuing to copy itself onto other disks.
4
1983 - The First Documented Experimental Virus
11
12
• 1990 Anti-virus software begins to appear
1991 Norton Anti-Virus software is released by Symantec.
13
1980s – 1994 virus Summary
• Boot sector virus
Virus written by two Pakistani brothers, Amjad and Basit Farooq Alvi.
Bootsector (of any disk) • information about the disk • Short program to display a message
10
1989 - AIDS Trojan First example of ransom（赎金）-ware?
• In the fall of 1989, approximately 10,000 copies of an “AIDS Information” package were sent out from a company calling itself PC Cyborg（半机械人）. • The program encrypted the hard disk. The user was then presented with an invoice（发票） and a demand to pay the license fee in return for the encryption（编码） key.
Well over 1,000 viruses are now thought to exist.
– 1981 Apple, Elk Virus – 1986 Brain Virus – Pakistani Virus
• • • • • •
File (Program) Virus – late 80s Internet Worm of 1988 AIDS Trojan Virus (example of ransom-ware) 1990s first anti- virus software 1991 Norton anti-virus software 1992 “the great scare” Michelangelo
tool against software piracy
6
From Virus to Worm
• (File) Virus: a program fragment that inserts itself into other programs • Worm: a program that propagates（传播） itself across a network, using resources on one machine to attack other machines.