UNIT6远古以来，传染病对人类历史有着引人注目的影响。
传染病影响了——并且受到了经济状况、战争和自然灾害的影响。
Since time immemorial, infectious diseases have had a dramatic impact on human history. They have affected—and been affected by—economic conditions, wars, and natural disasters.确实，传染病的影响可能远比已知的灾害大得多。
1918年席卷全球的流感流行使2千万～5千万人丧生，是第一次世界大战死亡人数的2～5倍。
ndeed, the impact of infectious diseases can be far greater than better-known calamities. An epidemic of influenza that swept the globe in 1918 killed from 20 million to 50 million people—two to five times more deaths than were caused by World War I.无论是新老传染病，继续在全球影响平民百姓。
全球每小时就有1 500人因传染病死去这一事实表明，传染病依然是全球的主要死因。
Infectious diseases, whether old or new, continue to affect citizens worldwide. The fact that 1,500 people die each hour as a result of infectious diseases indicates that infectious diseases remain a dominant cause of death.近100年来，人类开发出各种抗生素以便控制和根除传染病。
随着20世纪60年代新型抗菌药物和疫苗的开发，科学界曾认为可以宣称战胜了致病菌。
Over the past 100 years, humans have developed various antibiotics in order to control and eradicate infectious diseases. With the development of new classes of antimicrobials and vaccines in the 1960s, the scientific community thought it could claim victory over microbes.但是40多年后我们还将继续与像疟疾、结核病、麻疹、艾滋病、禽流感等新老传染病作斗争。
Yet some 40 years later, we continue to struggle with old and new infectious diseases like malaria, tuberculosis, measles, HIV, and bird flu.值得汲取的一个教训是：在继续研发疫苗和疗法的同时，国际社会必须在监测、检测和早期应对体系方面共同合作来与传染性疾病作斗争。
A worthwhile lesson is that, while continuing research and development of vaccines and therapies, the international community must cooperate in surveillance, testing, and early response systems to combat infectious diseases.1. Many women artists complain that their work ___is not taken seriously_(没得到严肃对待).2. ___Only by soaking yourself in the details_(只有靠沉浸于细节里) can you gain a thorough understanding of the subject.3. We had no reason to _suspect that he might try to kill himself__(猜疑他可能试图自杀).4. Tropical fevers can _ sweep through whole populations (迅速袭击全体人群) in a remarkably short time.5. The amount of money spent on treating disease is in sharp contrast to that spent on prevention(与用在预防上的资金形成鲜明对比).6. The worry over the likelihood of breast cancer prompted her to have a genetic testing(促使她去做遗传检测).7.It’s amazing how soon the pathogen _adapts to its new surroundings(适应其新的环境) to survive.8. His ears are so sensitive that they can pick up very faint sounds(很灵敏可以听到非常微弱的声音) from a long way away.9. The doctor will attach a special monitor to(把专门的监听器系缚在) the pregnant woman’s stomach so that she can list en to the baby’s heart.10. His share was more than all the others put together (比所有其他的合在一起还多).UNIT7干细胞是所有身体组织的来源，能够自身复制，或成为构建一个生物所必需的任何类型的细胞。
我们的成长和发展——从单一细胞到成熟的成人——起源于并由干细胞来维持。
Stem cells, source of all body tissues, can replicate themselves or make any type of cell required to build an organism. Our growth and development—from single cell to mature adult—arises from and is maintained by stem cells.此外，干细胞能为生物学研究和医疗提供强大的工具。
科学家们正在研究在医学中利用干细胞的两种主要方式。
Moreover, stem cells may provide powerful tools for biological research and medical treatment.Scientists are investigating two primary approaches to using stem cells in medicine.第1种方式涉及到培育可移植来同特定疾病作斗争的干细胞。
第2种涉及了解利用身体自身提供干细胞, 用作治疗各种疾病的出发点。
The first approach involves developing stem cells that could be transplanted to combat a specific disease. The second approach involves learning to use the body’s own supply of stem cells, which could serve as starting points in therapy for a wide variety of medical conditions.干细胞研究引起了很多争议。
很大部分争议是围绕着研究中使用的干细胞的来源。
一些反对使用胚胎干细胞的人指出科研人员可以依靠其他来源。
Stem cells research has stirred considerable controversy. In large part, the controversy revolves around the source of stem cells used in research. Some people who oppose the use of embryonic stem cells point out that scientific investigators could rely on other sources.种种身体组织，包括骨髓和脐带血，也能提供干细胞。
然而，这些组织产生的干细胞是否在其多用性和治疗人类疾病的潜能方面比得上胚胎细胞，还无人知晓。
A variety of body tissues—including bone marrow and blood from an umbilical cord—can also provide stem cells. However, no one knows if these tissues produce stem cells that equal embryonic cells in their versatility and thus in their potential for treating human disease.1. Nurses went back and forth among the wounded(护士们在伤员中来回走动), bringing food and medicine.2. They are determined to press ahead with their research project (奋力推进他们的研究项目) despite opposition from some medical ethicists.3. I’m sure that most doctors will approve of using stem cells_ (赞成使用干细胞) for medical research.4. The Football Association is likely tocall for a ban on alcohol(要求禁酒) at football games.5. Those rockets were built at a time when ___space technology was still in its infancy(空间技术还处于初期).6. The evidence before us points clearly to the side-effects(清楚地表明副作用) of the new painkilling drug.7. Recent findings suggest that crime victimsbenefit from talking about their experiences(受益于谈论他们的经历).8. The town was surrounded by the enemy and the citizens did not know if they could hang on until help arrived(他们能否坚持直到援助到来).9. There are a few things that need mopping up (需要完成) before I can leave.10. If we can get around these difficulties (避开这些困难), we’ll be able to discuss the really important points.UNIT8医学移植指的是将健康的活体组织或器官移植给一个受伤或有病的人，目的是使受者恢复健康或减少伤残Medical transplantation refers to the transfer of a living tissue or organ to an injured or ill person to restore health or reduce disability in a recipient.自从20世纪中叶器官移植首次成功以来，当代医学在给病重的人移植器官方面取得了巨大的进展Since the first successful organ transplant in the mid-1950, great strides have been made in contemporary medicine in its capability of implanting organs in people who are seriously ill.现在至少有20多种不同的器官和组织，如心、肝、肾、角膜和骨髓等，能够成功地移植入患者体内，这些患者能够生存数年甚至数十年。