大学医学英语课文翻译课文翻译.doc

第一单元 疾病介绍1 人体是一个艺术杰作。我们对身体功能了解越深，就越赏识它。即使在生病时，身体在故障修复和补偿方面表现也相当出色。身体内不断发生变化，然而，一个称之为内环境稳态平稳状态能大抵保持平衡。机体内环境稳态如果出现某种严重紊乱，就能诱发各种各样反响，显现疾病体征和病症。比方，由于运发动对氧气需求增加，他们体内红细胞计数就会异常升高。这是一个使更多血红蛋白循环自然补偿机制，但它却是红细胞增多症一个病症，这在下文中会有涉及。2 当一个器官需要做更多工作时，它往往会增大，肥大。心脏会因为血压高地一直不降而增大，因为它必须不连续地克制巨大阻力把血液输送到全身。当瓣膜存在缺陷时，心肌同样也会肥大，因为那些要么太宽，要么太窄瓣膜需要额外抽吸作用。如果一个肾衰竭了，另一个肾就会增大以满足身体需要，并弥补那个有缺陷肾。当流向这两个肾血液缺乏时，它们会通过分泌荷尔蒙激素使血压升高。然而，如果某个器官或身体某个部位没有得到使用，它就会萎缩，或者，也就是说，体积变小或功能下降。3 血液在维持内环境稳态上发挥着一些作用。当组织受到创伤，损伤，或者感染时，血流就会积聚在受损区域。这一点极其重要，因为血液携带细胞可专门去除有害物质和细胞碎片。 血液中其他细胞那么产生抗体，以抵抗致病微生物入侵。4 疾病是某个身体部位，生理系统，或整个机体不安康状态，其中构造或功能会发生紊乱。疾病经常始于细胞水平。一个异常基因不管是因遗传所得，还是因环境因素引起突变或变异，都能启动疾病程序。比方，当基因信息遭到侵袭常被病毒侵袭时，癌症发生会伴随着细胞疯长。新研究技术正使得某些疾病与异常基因研究结果联系起来成为可能。 疾病可以是一种构造性异常，比方，先天性心脏缺陷，也可以是没有器质性改变功能性病变。疾病可能是一种构造性异常，比方，先天性心脏缺陷，也可能是没有器质性变化功能性病变，比方，高血压或精神创伤。组织或功能异常称之为病变，一个病变可能是一处创伤，损伤，或一种病理疾病。5 关于疾病，一个重要方面是它病因学或病因。许多熟悉疾病是由病原体造成。普通感冒和流感都是病毒感染，但是脓肿和脓毒性链球菌咽喉炎是由细菌造成，而真菌和寄生虫分别是运发动足部疾病和蠕虫病病原体。一种疾病或异常病变原因及进展称之为疾病发病机制。6 病理学是研究疾病特点、原因和影响一个医学分支。细胞病理学家研究是细胞或显微镜变化，而临床病理学家那么利用实验室试验和方法进展诊断。一位病理学家可能擅长验尸或分析手术上观察结果。7 许多疾病是由遗传造成，经缺陷基因遗传。血友病、镰刀状细胞性贫血和色盲都属于基因病。智力上或身体上先天性缺陷可能是由于母亲妊娠期间感染风疹或德国麻疹、吸毒、过度饮酒所导致发育性失调。某些先天性缺陷是由于母亲分娩期间发生意外，比方供氧受到干扰而引起。8 环境因素可以导致许多疾病。比方，皮肤癌是由于过度暴露于太阳紫外线下而引起，尤其发生在肤色浅人群中。白血病发生是放射科医师职业病，这种癌症发生与暴露于石棉之中有关。研究发现，在工业废弃物中发现许多化学物质也致病。9 因营养不良导致许多疾病并不都是由于缺少食物，而是由于人们不能运用食物。营养缺乏病体征常常伴随慢性酒精中毒。10 应激对整个身体起反面作用：它降低免疫系统抗病能力。应激可致几种胃肠道系统疾病，比方：消化性溃疡和溃疡性结肠炎。它同样可加重呼吸道疾病如哮喘和其他过敏性疾病。如果疾病原因不详，称之为原发性疾病。11 关于疾病，另一个重要方面是它表现方式：即体征和病症。体征是在体检时观察到关于疾病客观证据，比方：脉搏率或呼吸频率异常，发烧和苍白。而病症是病人能感知疾病指征，比方：疼痛，头晕和瘙痒。本单元试图将疾病体征和病症与疾病特定机能障碍联系在一起。比方，为什么贫血病人会感到虚弱无力、疲惫不堪和气短？为什么甲状腺功能亢进甲亢会导致体重下降、紧张和出汗过量？为什么在某些心脏疾病中脚踝会肿胀？12 在一些疾病中，某些体征和病症会同时出现，多种病症综合在一起称之为综合征。先天愚型或唐氏综合征这种疾病具有多种并发体征，其中最显著体征是：智力发育障碍，舌体变大，舌头外伸，眼睛具有特异性外观斜视。13 诊断，即确定疾病性质，基于诸多因素，如体征、病症、常常还有实验室检查结果。实验室化验包括一些我们熟悉程序，比方，尿检，血检，心电描记术和放射照相术。像计算机化断层显像CT扫描，放射照相术，超声波和核医学这些全新诊断成像技术具有造影功能，这在以前是无法实现。用于确诊各种疾病诊断程序在每个系统中都有涉及。医生也可以从体检、与病人及其家属交谈、病人及其家族病史中获得信息，以便对疾病进展诊断。已经做出诊断医生要说明疾病可能预后，或预期病程，和疾病后果。14 通过开处方，以确定最有效治疗方案，方案可包括：药物治疗、手术、放射疗法、或心理咨询。建议病人改变生活习惯，比方：暴食、吸烟、酗酒、或者尽可能不让病人受到刺激。15 疾病过程各异。它可能发病急，病程短，这种情况属于急性病；也可能不知不觉地发生，持续时间长，或是慢性。“chronic这个术语源于表示时间希腊词“chronos。可致死疾病叫做晚期疾病。慢性病体征和病症在缓和期有时会减轻，在恶化期可能会再次出现，十分严重。某些疾病如白血病和溃疡性结肠炎一个重要特点就是具有病症缓和期和恶化期。有时，一种疾病在明显终止后几周或几个月会复发。16 并发症也常常出现，即患者得某种病后，还会并发另一种病。严重骨折，并卧床不起患者由于无法活动，往往会并发肺炎。腮腺炎可能会并发睾丸感染，尤其是在青春期后。一般情况下，白血病、癌症和慢性肾病都伴有贫血。某些诸如肾结石、心脏缺陷和前列腺肥大等发病诱因常伴有细菌感染。17 疾病后果叫做后遗症，一种遗患。风湿热之后心脏遭受永久损伤是一种后遗症，正如瘫痪也是小儿麻痹症后遗症一样。由输卵管严重炎症引起不孕不育症也是一种后遗症。18 疾病有多种分类方法。比方，可根据疾病一般机制分类，也可将之放在生理系统中考虑，因为疾病是其中一个因素。一般疾病包括：过敏、营养不良、肥胖症和酒精中毒。19 了解疾病及其原因、疾病对身体发生何种影响、有效疾病治疗方案以及疾病预后有助于医务人员减轻患者痛苦、焦虑和恐惧感。20 机体试图在不断变化情况下维持内环境稳定。当它感觉到某个器官在工作过程中存在缺陷，便会尽力去补偿。当机体内环境稳态出现严重紊乱时，发生反响与疾病体征相似。21 疾病是某个身体部位、某个系统或整个身体不安康状态，它可能由构造性异常、功能性病变或外伤引起。致病因素有很多：传染性病原体、遗传、环境、营养不良和应激。有时，病因不详。病原学研究是疾病原因，而病理学那么是研究疾病病原学、特点和影响，即发病机制一门医学分支。22 疾病表达在体征和病症，即疾病存在主、客观指征上。和唐氏综合征一样，在某些疾病中，多种体征和病症可同时出现。23 疾病诊断基于多种因素：体征和病症、实验室化验、体检，和病人及其家族病史。接着，开处方确定最适宜治疗方案。疾病具有急性和慢性之分，慢性病体征常常会消退或恶化。了解疾病各个方面能帮助医务人员全面地为病人效劳。艾滋病在研究和治疗方面新进展History艾滋病历史Acquired Immune Deficiency Syndrome (AIDS) was first clinically observed in 1981 in the United States. The initial cases were a cluster of injecting drug users and homosexual men with no known cause of impaired immunity who showed symptoms of Pneumocystis carinii pneumonia (PCP), a rare opportunistic infection that was known to occur in people with very compromised immune systems. Soon thereafter, an unexpected number of gay men developed a previously rare skin cancer called Kaposi's sarcoma (KS). Many more cases of PCP and KS emerged, alerting U.S. Centers for Disease Control and Prevention (CDC) and a CDC task force was formed to monitor the outbreak. 1981年，美国确诊了第一例获得性免疫缺陷综合征即艾滋病。最初病例是一群不知什么原因免疫力受损注射吸毒者和男同性恋者，他们表现出卡氏肺孢子虫肺炎病症，据称这是一种发生在免疫系统严重受损人群中罕见时机性感染。此后不久，许多男同性恋者出乎意料地得了一种以前很少见叫卡波济肉瘤皮肤癌。后来出现了更多卡氏肺孢子虫肺炎和卡波济肉瘤病例，给美国疾病控制与预防中心CDC发出了警报，于是，成立了一个特别小组去监测艾滋病爆发。In the early days, the CDC did not have an official name for the disease, often referring to it by way of the diseases that were associated with it, for example, lymphadenopathy, the disease after which the discoverers of HIV originally named the virus. They also used Kaposi's Sarcoma and Opportunistic Infections, the name by which a task force had been set up in 1981. At one point, the CDC coined the phrase “the 4H disease, since the syndrome seemed to affect Haitians, homosexuals, hemophiliacs, and heroin users. In the general press, the term "GRID", which stood for gay-related immune deficiency, had been coined. However, after determining that AIDS was not isolated to the gay community, it was realized that the term GRID was misleading and the term AIDS was introduced at a meeting in July 1982. By September 1982 the CDC started referring to the disease as AIDS. 在早期，美国疾病控制与预防中心对这种疾病并没有一个官方名字，谈及这种疾病时通常用与之相关疾病代替，比方：淋巴结病，人体免疫缺陷病毒发现者最初就是以这种疾病给该病毒命名。他们同样也使用过卡波济肉瘤和时机性感染，1981年一个特别小组成立时就是用这个名称。美国疾病控制与预防中心曾经创造过一个短语“4H疾病，因为这种综合征似乎更易感染这四种人海地人，同性恋者，血友病患者和吸食毒品者。在普通报刊中，创造了一个术语“GRID，表示与同性恋有关免疫缺陷。然而，在人们确定AIDS并非仅存在于同性恋群体中后，认识到“GRID 这个术语容易引起误解。于是，在1982年7月召开一次会议上首次引入AIDS这个术语。到1982年9月，美国疾病控制与预防中心开场把这种疾病称作艾滋病AIDS。In 1983, two separate research groups led by Robert Gallo and Luc Montagnier independently declared that a novel retrovirus may have been infecting AIDS patients, and published their findings in the same issue of the journal Science. Gallo claimed that a virus his group had isolated from an AIDS patient was strikingly similar in shape to other human T-lymphotropic viruses (HTLVs) his group had been the first to isolate. Gallos group called their newly isolated virus HTLV-III. At the same time, Montagniers group isolated a virus from a patient presenting with swelling of the lymph nodes of the neck and physical weakness, two characteristic symptoms of AIDS. Contradicting the report from Gallos group, Montagnier and his colleagues showed that core proteins of this virus were immunologically different from those of HTLV-I. Montagnier's group named their isolated virus lymphadenopathy-associated virus (LAV). As these two viruses turned out to be the same, in 1986, LAV and HTLV-III were renamed HIV. Since that time, the number of people infected with the causative virus of the syndrome and of those who die from the various consequences of the infection, has grown considerably.1983年，由罗伯特·加洛和吕克·蒙塔尼耶领导两个独立研究小组宣称一种新逆转录病毒可能感染艾滋病患者，并将他们研究结果发表在同一期?科学?杂志上。加洛称，他研究小组从艾滋病患者体内别离出一种病毒，与他们在世界上首度别离出那些其他人类T淋巴细胞病毒HTLV在形状上惊人地相似。加洛研究小组将这一新别离病毒称为HTLV-III型病毒。与此同时，蒙塔尼耶研究小组从一个身体虚弱，颈部淋巴结肿胀艾滋病两大典型病症患者体内别离出一种病毒。与加洛研究小组报告相反是，蒙塔尼耶和他同事指出这种病毒核心蛋白在免疫学上不同于HTLV-I型。蒙塔尼耶研究小组把他们别离出来病毒命名为淋巴腺病相关病毒LAV。由于这两种病毒实际上属于同一种病毒，于是，1986年LAV病毒和HTLV-III型病毒被重新命名为HIV病毒。从那以后，感染艾滋病致病病毒和死于这种感染各种各样后果人数大幅增加。Research on AIDS艾滋病方面研究In the 1980s and 1990s, researchers were able to establish that the principal target for the maladies associated with AIDS is the immune system. Since then, much research has been directed towards pinpointing the changes in the human immune system due to infection, seeking ways of reversing these changes, or supplementing the compromised immune system to hold the infection in check.二十世纪八、九十年代，研究人员证实，艾滋病相关疾病主要攻击目标是免疫系统。自那时起，许多研究开场转向探究感染前后人类免疫系统变化情况，寻求扭转这些变化方法，或增强受损免疫系统免疫力使之能够抑制这种感染。The particular immune system component that has been implicated in the progression of AIDS is a type of T cell called the CD4 T cell. This cell, which is activated following recognition of the virus by the immune system, functions in the destruction of the cells that have been infected by the virus. Over time, however, the number of CD4 cells declines. If the decline decreases the T cell count to below 200 per microliter of blood, the number of infective virus particles goes up steeply and the immune system breaks down. This loss of the ability to fight off foreign organisms leaves the patient open to life-threatening illnesses that normally would be routinely defeated by an unimpaired immune system.在艾滋病开展过程中，涉及一种叫CD4T细胞，它是免疫系统一个特殊组成局部。免疫系统识别艾滋病病毒后，CD4T细胞被激活，继而在被病毒感染细胞破坏过程中发挥着重要作用。然而，随着时间推移，CD4细胞数量在下降。如果每微升血液中T细胞计数低于200个，那么感染性病毒粒子数量就会急剧增加，免疫系统也随之崩溃。免疫系统丧失了抵御外来生物体能力，这使得病人更易患那些危及生命疾病，因为免疫系统在未遭到损害情况下一般能战胜这些疾病。 Until 2001, the prevailing view was that the decline in the number of CD4 cells was due to a blockage of new T cell production by the infecting virus. However, the conclusions from studies published in 2001 now indicate that the production of new T cells is not blocked, but rather that there is acceleration in the loss of existing T cells. Even though the result is the same, namely the increased loss of the specialized AIDS-fighting T cells, the nature of the decline is crucial to determine in order to devise the most effective treatment strategy. If the reasons for the accelerated loss of the T cells can be determined, perhaps the loss can be prevented. This would better equip patients to fight the infection.在2001年以前，人们普遍认为，CD4细胞数量下降是由于新T细胞产生遭到感染病毒阻断。然而，2001年公布一些研究结论现在说明新T细胞发生并没有被阻断，而是现有T细胞却在加速减少。尽管结果都是一样，即那些专门抗艾滋病T细胞都在加速减少，但是，T细胞数量下降实质对于我们确定并制定最有效治疗策略是至关重要。如果能确定/找到T细胞加速减少原因，或许就能防止这种情况发生。这能使病人更好地对抗感染。Treatment of AIDS艾滋病治疗Since 1998, a multi-pronged strategy of AIDS therapy has been established. Highly Active Anti-Retroviral Therapy (HAART) consists of administering a "cocktail" of drugs targeted to the AIDS virus to a patient, even when the patient shows no symptoms of AIDS. The drug mixture typically contains a so-called nucleoside analog, which blocks genetic replication, and inhibitors of two enzymes that are critical enzyme in the making of new virus (protease and reverse transcriptase).1998年以来，对艾滋病治疗确立了一种多管齐下策略。高效抗逆转录病毒疗法包括给予患者一种针对艾滋病病毒“鸡尾酒药物，即使当患者尚未表现出艾滋病病症。这种混合药物通常包含一个所谓能阻断基因复制核苷类似物，及蛋白酶和逆转录酶抑制剂，这两种酶在新病毒形成过程中至关重要。HAART has greatly reduced the loss of life due to AIDS. But, this benefit has come at the expense of side effects that can often be severe. Also, the treatment is expensive. But now, research published toward the end of 2001 indicates that the use of HAART in a “7-day-on, 7-day-off cycle does not diminish treatment benefits, but does diminish treatment side effects. Costs of treatment have become more reasonable, as well.高效抗逆转录病毒疗法能大大减少因感染艾滋病而导致死亡人数。但是，这种好处是以副作用为代价，而这种副作用往往可能会很严重。而且，这种治疗方法是很昂贵。而现在，2001年年底发表研究说明，一种“用7天停7天高效抗逆转录病毒疗法并没有减弱治疗效果，却实实在在减少了治疗副作用。同样，治疗费用也变得更为合理。Another advancement in AIDS treatment may come from the finding that the inner core of the AIDS virus, which is called the nucleocapsid, is held together by structures known as "zinc fingers". There are drugs that appear to break apart these supports. This stops the virus from functioning. Furthermore, evidence supports the view that the nucleocapsid does not change much over time. Thus, a drug that effectively targeted the nucleocapsid could be an effective drug for a long time. The drawback to this approach at the present time is that other structures in the body utilize zinc fingers. So, an anti-AIDS zinc finger strategy will have to be made very specific.在艾滋病治疗上取得另一个进展可能源于一个发现：艾滋病病毒内核即核衣壳由“锌指构造固定在一起。有些药物似乎能打破这种构造，继而阻止病毒运行。而且，有证据说明，随着时间推移，核衣壳并没有太大变化。因此，一种有效针对核衣壳药物在相当一段时间内都是有效药。目前，这种药物治疗方法缺陷在于锌指构造能被身体其他构造所利用。因此，抗艾滋病锌指构造治疗策略应制定地非常具体。In the mid 1980s, there was great optimism that a vaccine for the AIDS virus would be developed within two years. However, this optimism soon disappeared. In late 2001, however, preliminary clinical trials began on a candidate vaccine. Traditional vaccines rely on the administration of a protein to stimulate the production of an antibody that confers protection against the disease-causing organism. The candidate vaccine works by targeting what is called cell-mediated immunity. This type of immunity does not prevent infection, but rather clears the virus-infected cells out of the body. Such a vaccine would be intended to prolong and enhance the quality of the lives of AIDS-infected people. Studies in monkeys have been encouraging. However, studies must still rule out the possibility that vaccination would create "carriers," individuals who are not sick but who are capable of spreading the disease.在20世纪80年代中期，人们乐观地认为，针对艾滋病病毒疫苗会在两年内研制出来。然而，这种乐观情绪很快就消失殆尽了。2001年年底，已经开场就候选疫苗进展初步临床试验。传统疫苗依靠蛋白质管理去刺激抗体产生，使之免受致病生物体侵害。候选疫苗通过作用于细胞介导免疫而起作用。这种免疫并不能防止感染，而是能把被病毒感染细胞去除出体外。这种疫苗是用来延长和提高艾滋病感染者生活质量。在猴子上做实验结果还令人鼓舞。然而，研究还必须排除一种可能性接种疫苗可能会发生病原携带者，即那些未发病，却能传播疾病人。There are various vaccine treatment strategies. One involves the injection of so-called "naked" DNA. The DNA contains genes that code for gag, a viral component thought to be critical to the development of AIDS. The DNA can be attached to inert particles that stimulate the response of the immune system. In another strategy, the viral gene is bundled into the DNA of another virus that is injected into the patient.有各种各样疫苗治疗方法。一种方法涉及注射一种所谓“裸露DNA。DNA包含为聚糖编码基因，聚糖是一种在艾滋病开展过程中起关键作用病毒成分。DNA可附着于能刺激免疫系统应答惰性粒子。另一个方法是，把病毒基因注入到另一个病毒脱氧核糖核酸里，然后注射到病人体内。As of 2002, more than two dozen experimental vaccines intended to control, but not cure, AIDS infections are being studied worldwide. Treatment strategies, vaccine-based or otherwise, will need to address the different isolates of the AIDS virus that are present in various regions of the globe. These different isolates tend to be separated into different geographical regions. Even within a geographical area, an isolate can display variation from place to place. Thus, it has become clear that a universal treatment strategy is unlikely.截止到2002年，二十几个实验性疫苗都是旨在控制而非治愈，艾滋病感染正成为全球性研究课题。以疫苗为根底或其他治疗方法需要解决不同艾滋病病毒隔离人群问题，这些人分布在全球各个地区。这些不同隔离人群往往分散于不同地理区域。即使在同一个地理区域里，一个隔离人群也会因位置不同而呈现差异。因此，很显然，一个通用艾滋病治疗方案不太可能实现。Stem Cell Transplantation干细胞移植In 2007, Timothy Ray Brown, a 40-year-old HIV-positive man, also known as "the Berlin Patient", was given a stem cell transplant as part of his treatment for acute myeloid leukemia (AML). A second transplant was made a year later after a relapse. The donor was chosen not only for genetic compatibility but also for being homozygous for a CCR5-32 mutation that confers resistance to HIV infection. After 20 months without antiretroviral drug treatment, it was reported that HIV levels in Brown's blood, bone marrow, and bowel were below the limit of detection. The virus remained undetectable over three years after the first transplant. Although the researchers and some commentators have characterized this result as a cure, others suggest that the virus may remain hidden in tissues such as the brain (which acts as a viral reservoir). Stem cell treatment remains investigational because of its anecdotal nature, the disease and mortality risk associated with stem cell transplants, and the difficulty of finding suitable donors. 2007年，蒂莫西·雷·布朗，一个40岁艾滋病病毒阳性患者，也被称为“柏林病人，因患急性骨髓样白血病承受了一次干细胞移植。一年后，他旧病复发，承受了第二次移植手术。骨髓捐献者选择不仅要在基因上相容，而且与CCR5-32变异基因能够同型结合，这种变异基因能够抵抗艾滋病病毒感染。据报道，连续20个月未给予抗逆转录病毒药物治疗后，布朗血液、骨髓和肠道中艾滋病病毒水平均低于检测界限。第一次移植后，三年来艾滋病病毒都没有在布朗体内检测到。虽然研究人员和一些评论家把这种结果视为一种治愈方法，但是，其他人那么认为，这种病毒可能藏匿于一些组织中，比方：大脑病毒贮存宿主。由于干细胞疗法性质无法确定，具有与干细胞移植相关疾病和死亡风险，且