五、医学与健康
TEXT 46
The controversy began about 10 years ago，when it emerged that the National Football League had first tried to cover up evidence linking repetitive head injuries in players to chronic traumatic encephalopathy（CTE），a progressive neurodegenerative disorder，and then to discredit the scientists doing the work.The largest-ever study of its kind has now given the most compelling evidence yet linking repetitive head impacts in football players to CTE.
The new work builds on findings from 2013：neuropathologist Ann McKee of Boston University and her colleagues published a postmortem report of 68 male athletes and military veterans with CTE，in which they described a spectrum of pathological signatures associated with the condition.McKee and colleagues observed two distinct sets of clinical symptoms：one involving disturbances in mood and behavior，which was seen in the younger subjects，and the other including cognitive impairments，which developed at an older age.
Based on their findings the team proposed a number of pathological criteria for the diagnosis of CTE，similar to those for Alzheimer's disease.Their proposal also identified stages by which these pathologies and the behavioral symptoms associated with them become more severe with time.According to the criteria set out by the researchers，early symptoms of CTE include headaches and attention deficits，progressing later to depression and short-term memory loss，then to cognitive impairments and finally to full-blown dementia and aggression.
Despite the high proportion of study participants exhibiting CTE pathology，the authors urge caution in interpreting their results.One important limitation of the study is the biased sample—brains that were donated for the specific purpose of examining links between head trauma and CTE.It does not necessarily follow that the frequency of CTE in the wider population of people exposed to repetitive head injuries is as high as that found in the study.Nor is the sample representative of the overall population of football players，most of whom play only on youth or high school teams.“Our sample has very clear ascertainment bias，”says study co-author Bobby Abdolmohammadi，a research assistant in McKee's lab.“That is，families may have been motivated to donate the brains of their loved ones because they saw symptoms or were aware of the link between repetitive head trauma and football，[so] we can't jump to any conclusions about the frequency of the disease in the general population or amongst football players at this point.”
Abdolmohammadi adds that determining the precise nature of the relationship between repetitive head injuries and CTE would require well-designed longitudinal studies.Such research may finally begin to determine the true impact of repetitive concussion on brain structure and function.
1.Strong evidence links____.
[A] mental disorder to players
[B] athletes to military veterans
[C] football to brain disease
[D] head injuries to football
2.McKee and her team studied____.
[A] the impacts the subjects’ brain structure receives
[B] the clinical symptoms associated with CTE
[C] the link between mood and behavior damage
[D] the cognitive impairment brought on by aging
3.Which of the following marks is a later stage of CTE?
[A] Experience of low mood.
[B] Failure to concentrate and recall.
[C] Inability to recognize patterns.
[D] Tendency to fight when offended.
4.We should be cautious about the research results because____.
[A] the subject's families require the results kept secret
[B] there is an obvious flaw in choosing the samples
[C] CTE has turned out to be a complicated condition
[D] the participants are not satisfied with the results
5.Bobby Abdolmohammadi is quoted to____.
[A] warn not to reach general conclusions
[B] overthrow the results of the study
[C] describe his design of longitudinal study
[D] express his dissatisfaction with the study
考研必备词汇
其他词汇
1.encephalopathy 脑病
2.neurodegenerative 神经组织退化的
3.neuropathologist 神经病理学家
4.postmortem 死后的
5.Alzheimer's disease 老年痴呆症
6.dementia 痴呆
7.concussion 震动，震荡
疑难长句注解
1.The controversy began about...doing the work.（第一段）
这个句子很长，主干结构是 The controversy began about 10 years ago，when it emerged that the National Football League had first tried to...，and then to...。其中，when引导非限定性定语从句，在定语从句中that...work是主语从句，有两个并列的谓语，用first和and then连接，it是形式主语。词组cover up意为“掩盖”，特别指掩盖错误或不合法行为，discredit意为cause somebody/something to be disbelieved（使某人/某事不再被相信）。
2.“That is，families may have been...at this point.”（第四段）
这个句子是对上一句中提到的ascertainment bias举例说明，这是统计医学中常见的一种抽样偏差或代表性偏差。本句中，loved ones一般指家人，general population指样本之外的全部人，at this point意为“在此刻，在此时”。
译文
争议开始于约10年前，当时发生了这样的事情：全国橄榄球联盟起初试图掩盖证据，这些证据把球员头部重复受伤与慢性创伤性脑病（CTE）联系在一起，这是一种渐进性神经系统退化紊乱症；然后其又败坏做这些研究的科学家的名誉。现在，一项有史以来最大规模的类似研究提供了令人信服的证据，仍然把橄榄球球员的重复头部冲撞与CTE联系在一起。
新的研究建立在2013年以来的发现之上：神经病理学家波士顿大学的Ann McKee及其同事发表了68人的验尸报告，他们都是患CTE的男性运动员和退伍军人，报告中描述了与这种病相关的一系列病理学特征。McKee及其同事观察到两组清晰的临床症状：一组涉及情绪和行为失调，在年轻一些的受试者身上能看到；另一组包括认知损伤，在年龄大的受试者身上出现。
基于这些发现，这个小组为诊断CTE提出了多个病理学标准，类似于诊断阿尔茨海默病的标准。他们在提议中也区分出这些病理特征和与之相联系的行为症状日趋严重的阶段。按照研究者设定的标准，CTE早期的症状包括头痛、注意力欠缺，后来过渡到抑郁和短期失忆，然后是认知损伤，最后到完全痴呆和攻击性。
虽然有高比例的研究参与者表现出CTE的病理特征，但是作者强调在解释研究结果时要谨慎。这项研究的一个重要局限性是它抽样偏差——即这些大脑是被捐出、专门用来检验头部创伤和CTE关系的。研究结果并不意味着在头部重复受到伤害的更广泛的人中，患上CTE的频率会像研究中的那些人那样高。这也不意味着样本代表橄榄球队员中的全部人员，这些人大部分只在年轻时或在高中队里踢球。这项研究的合作作者Bobby Abdolmohammadi是McKee实验室的研究助理，他说，“我们的样本存在一个清楚的确认偏差，即家属们有捐献亲人大脑的动机，因为他们看到了症状，或者意识到重复头部创伤和橄榄球的联系，[所以] 有关普通人或橄榄球员患CTE的频率，我们目前不能盲目得出结论”。
Abdolmohammadi补充说，确定脑部重复受伤和CTE之间的联系的确切本质，将需要设计严谨的纵向研究。这种研究最终才能开始决定重复脑震荡对大脑结构和功能的真实影响。
TEXT 47
A few decades ago，doctor-assisted suicide was considered an eccentric idea despite surveys showing many physicians supported the idea under certain circumstances.The face of euthanasia at that time was Jack Kevorkian，a Michigan pathologist nicknamed“Dr.Death.”He was convicted of homicide and served eight years in prison.Allowing assisted dying to come into the open has helped us gain insights about one of the most fundamental questions of our existence：Where do humans draw the line between choosing life and choosing death?
But a study released Wednesday in the New England Journal of Medicine suggests the answers may be surprising：The reasons patients gave for wanting to end their lives had more to do with psychological suffering than physical suffering.The study，based on information from Canada's University Health Network in Toronto，represents all 74 people who inquired about assistance in dying from March 2016 to March 2017.For many people，death from a terminal illness may be synonymous with pain.Much of the discussion about assisted suicide focuses on compassionate palliative care for cancer patients and about suffering that can't be controlled by even the strongest medication.But that's not what the people in the new study report.“It's what I call existential distress，”explained researcher Madeline Li，an associate professor at University of Toronto.
One of the main things these patients bring up has to do with“autonomy.”It's a broad philosophical concept that has to do with being able to make your own decisions，not being dependent on others，wanting to be able to enjoy the things you enjoy and wanting dignity.One patient was a marathon runner before her cancer left her confined to bed.“That was not how she saw her identity，”Li said.Another patient，a university professor，identified his intellect as the most important quality that he values in himself：“He had a brain tumor，and he didn't want to get to the point of losing control of his own mind.”
A study published in 2015 based on interviews with 159 patients or family members of deceased patients in Oregon—which allowed physicians to give prescriptions for self-administered lethal medications in 1997—found similarly complex psychological motivations for decisions.“These patients considered a hastened death over prolonged periods of time and repeatedly assessed the benefits and burdens of living versus dying，”researchers wrote.“None of the participants cited responding to bad news，such as the diagnosis of cancer，or a depressed mood as motivations for interest in hastened death.Lack of access to health care and lack of palliative care also were not mentioned as issues of concern.”
1.Dr.Jack Kevorkian was put into prison for____.
[A] failing to help patients to recover
[B] revealing private medical information
[C] helping patients to take suicide
[D] killing patients with wrong medication
2.The new study shows that____.
[A] there is no difference between choosing life or death
[B] distress，not pain，leads people to assisted suicide
[C] people seldom consider the fundamental questions
[D] cancer causes both psychological and physical suffering
3.By“existential distress”，Madeline Li means that____.
[A] compassion makes cancer patients' life easier
[B] no medicines can cure terminal illness so far
[C] no medication can control cancer patients' pain
[D] prolonging life means mental pain for the terminally ill
4.The university professor worried that____.
[A] he could not live a dignified life
[B] the operation on his tumor would fail
[C] he could not enjoy life as much
[D] his intellect would not be valued
5.The patients in Oregon cared more about____.
[A] the loss of control over their own life
[B] the prescriptions given by their doctors
[C] the inability to get qualified care
[D] the shock bad news brought to them
考研必备词汇
其他词汇
1.palliative 减轻的，缓和的
2.self-administered 自我实施的
疑难长句注解
1.A study published in 2015...for decisions.（第四段）
本句中，deceased patients指已过世的绝症病人，self-administered lethal medication（自我实施的致命用药）跟assisted suicide一样都指安乐死。
2.These patients considered...researchers wrote.（第四段）
本句中，hastened death指选择安乐死，the benefits and burdens of living versus dying指选择继续活下去和采用安乐死尽早结束自己的生命，两种选择各自的利弊（利益和负担）。
3.None of the participants...hastened death.（第四段）
本句中，the participants指参与采访的病人，cited意为“提到”（这里与as搭配，意为“提到……作为……）”，responding to bad news指听到自己被诊断出癌症后的反应，interest in hastened death指对安乐死感兴趣，即打算采用安乐死结束自己的生命。
译文
几十年前，医生协助的自杀被认为是一个怪想法，尽管有调查显示许多医生在某些情况下支持这种想法。那时，安乐死的代表人物是Jack Kevorkian，密歇根州的一位病理学家，人送外号“死亡先生”。他被判杀人罪而监禁八年。让协助死亡公开化有助于我们深入认识我们生存的一个最基本问题：人们如何界定选择生或死的界限？
但是，《新英格兰医学杂志》星期三发表了一项研究，它给出的答案可能令人惊奇：针对结束生命，病人给出的理由更多地与心理痛苦而不是身体痛苦有关。这项研究基于位于多伦多的加拿大的大学健康网络的信息，代表2016年3月至2017年3月期间全部74位咨询过协助自杀的人。对很多人来说，由晚期疾病导致的死亡可能是痛苦的代名词。关于医生协助自杀进行的讨论，大多数集中于给予癌症病人同情的姑息疗法，集中于那些甚至连最强的用药也无法控制的痛苦。但是，这不是参与这项新研究的人所说的。“这是我称之为存在的悲痛的东西”，研究者Madeline Li解释说，她是多伦多大学副教授。
这些病人提出的重要问题之一与“自主”有关。这是一个广义的哲学概念，涉及是否有能力做出自己的决定，不依靠其他人，想要有能力享受自己能享受的东西，想要保持尊严。一位病人曾是马拉松选手，但癌症使她困于床上。Li说，“这不是她看待自己身份的方式”。另外一位病人是大学教授，他把智力看作自己身上最重要的特质。“他脑部患有肿瘤，他不想等到自己的心智达到完全失控的程度。”
2015年发表的一项研究基于对俄勒冈159名病人或亡故病人的家属的采访——这些采访使得医生能在1997年为自我实施的致命用药开出药方——这项研究发现了做出决定时类似的复杂心理动机。“这些病人在很长时间内都在考虑加速死亡，他们不断权衡着活着和死亡各自的利弊”，研究者写道，“所有参与采访的人都没有说对倒霉事，比如被诊断为癌症或抑郁情绪的反应是他们选择加速死亡的动机。缺乏医疗条件、缺乏姑息疗法也没有被他们提到是自己担心的事情”。
TEXT 48
Marijuana's potentially detrimental impact on the developing brains of adolescents remains a key focus of research—particularly because of the possibility teenage users could go on to face a higher risk of psychosis.
New findings may fuel those worries.At the World Psychiatric Association's World Congress in Berlin on October 9，Hannelore Ehrenreich of the Max Planck Institute of Experimental Medicine presented results of a study of 1,200 people with schizophrenia.The investigation analyzed a wide range of genetic and environmental risk factors for developing the mental illness.The results—being submitted for publication—show people who had consumed cannabis before age 18 developed schizophrenia approximately 10 years earlier than others.The higher the frequency of use，the data indicated，the earlier the age of schizophrenia onset.In her study neither alcohol use nor genetics predicted an earlier time of inception，but pot did.
Other studies，although not all，support the thrust of Ehrenreich's findings.“There is no doubt，”concludes Robin Murray，a professor of psychiatry at King's College London，that cannabis use in young people increases the risk of developing schizophrenia as an adult.Speaking at the Berlin conference，Murray—one of the first scientists to research pot's link to the disorder—cited 10 studies that found a significant risk of young cannabis users developing psychosis.He also mentioned three other studies that identified a clear trend but had a sample size that was too small to reach statistical significance.
Interpretations of these new findings are hardly likely to receive universal acceptance. Questions about the cannabis—psychosis link have persisted for years.“The available data on this subject is far from definitive—particularly with regard to any potential cause-and-effect relationship，”notes Paul Armentano，deputy director of NORML，a U.S. organization that advocates marijuana legalization for adults.“For instance，increased cannabis use by the public has not been followed by a proportional rise in diagnoses of schizophrenia or psychosis.”
In 2015 the Toronto-based International Center for Science in Drug Policy issued a report—“State of the Evidence：Cannabis Use and Regulation”—that detailed this discrepancy.Recent research on marijuana is starting to address the type of questions that might ordinarily be revealed via lengthy clinical trials during the development of a pharmaceutical.This process is occurring as the legalization bandwagon picks up speed.In the U.S. marijuana use among high school seniors is more common than smoking cigarettes.The researchers at the Berlin conference discussed the need to alert the public about worrying new findings.
1.Research presented at a Berlin conference shows____.
[A] teenagers are more susceptible to mental diseases
[B] marijuana use hastens the onset of schizophrenia
[C] genetic factors have nothing to do with schizophrenia
[D] people with schizophrenia use marijuana frequently
2.The word“pot”（Para. 2）comes closest in meaning to____.
[A] marijuana
[B] psychosis
[C] schizophrenia
[D] inception
3.The three studies cited by Robin Murray____.
[A] clearly related marijuana use with earlier onset of psychosis
[B] provided counter-evidence to the 10 studies he mentioned
[C] were dismissed as contributing nothing to psychosis research
[D] failed to show any link between psychosis and cannabis use
4.The attitude of Paul Armentano to Murray's conclusions is one of____.
[A] admiration
[B] suspicion
[C] dismissal
[D] tolerance
5.As advocates for pot legalization step up their effort，____.
[A] more and more counter-evidence has been found
[B] many clinical experiments have to be postponed
[C] more and more questions have been answered
[D] opponents to pot use speed up their research
考研必备词汇
其他词汇
1.psychosis 精神错乱
2.schizophrenia 精神分裂症
3.cannabis 大麻
4.pot 大麻
5.pharmaceutical药物
疑难长句注解
1.In her study neither...pot did.（第二段）
本句中，predicted an earlier time of inception跟上一句中the earlier the age of schizophrenia onset是一样的意思，其中inception和onset都是“开端”的意思。后半句中pot did是省略句，即pot predicted an earlier time of inception，意为吸食大麻预示着患精神分裂症的时间提前。
2.“For instance，increased cannabis use...psychosis.”（第四段）
这个句子的意思是说：人们使用更多的大麻，并不意味着他们患精神分裂症或精神错乱症的概率相应地增长。
译文
大麻对青少年正在发育的大脑的潜在伤害性影响仍然是研究的一个关键点——特别是因为青少年吸食者可能继续面临更大精神错乱的风险。
新的发现可能会加重这些担忧。世界精神病学协会的国际大会10月9日在柏林召开，会上马克斯·普朗克实验医学院的Hannelore Ehrenreich介绍了对1200名精神分裂症病人的研究结果。该研究分析了导致精神疾病的范围很广的遗传和环境风险因素。结果（待出版）显示，在十八岁之前吸食过大麻的人比其他人患精神分裂的时间将近早十年。数据显示，使用频率越高，开始精神分裂的年龄越早。在她的研究中，喝酒和遗传基因都不预示着患病开始更早，但是大麻会。
其他研究——虽然不是所有研究——也支持Ehrenreich的主要发现。伦敦国王学院精神病学教授Robin Murray总结说，“毫无疑问”，年轻人使用大麻增加了成年后患精神分裂症的风险。Murray是最早研究大麻与精神紊乱关系的科学家之一，在柏林大会发言时，他引述了十项研究，这些研究都发现年轻的大麻吸食者患精神错乱的风险显著增加。他还提到三项其他研究，它们都看到了清晰的患病趋势，但是其抽样太小，不具备统计意义。
对这些新发现的解释不太可能受到普遍接受。有关大麻和精神错乱关系的疑问还将持续多年。NORML这个美国组织支持把大麻对成年人合法化，其副主任Paul Armentano指出：“这个方面可获得的数据根本不确定——特别是有关潜在因果关系的数据。比如，公众增加大麻使用后，并没有被更大比例地诊断出精神分裂症或精神错乱病。”
在2015年，位于多伦多的国际药物政策科学中心发布了一份报告：《证据状态：大麻的使用与管制》，报告详细展示了这种分歧。对大麻的最新研究开始回答通常在研制药物时通过漫长的临床实验才能解释的那类问题。随着大麻合法化的宣传潮流的加速，研究过程也在加速。在美国，高中高年级学生中使用大麻的情况比抽烟更常见。柏林大会上的研究者讨论有必要用这些令人担忧的新发现去警示公众。
TEXT 49
As daylight saving time ends，the UK will switch from British summer time（BST）to Greenwich mean time（GMT），heralding the start of lighter mornings but darker evenings. Modern daylight saving time（DST）is a little over 100 years old.It was first introduced in the city of Orillia in Ontario in 191112.The idea's big breakthrough came during the first world war when Germany introduced DST on 30 April 1916 to alleviate hardships from wartime coal shortages and air raid blackouts.Britain，most of its allies and many European neutrals soon followed suit.
But a small boost to our nightly slumber can improve memory and increase learning capacity.In a study published in Current Biology，Prof Matthew Walker，director of the Center for Human Sleep Science at Berkeley，and his team demonstrated that during a demanding memorising task，test subjects who were allowed extra nap time performed better than those who did not.The researchers found the brain's ability to learn was linked to sleep spindles：fast pulses of electricity generated during REM（rapid eye movement）sleep.They found that those who had less sleep struggled with mental agility tasks.
It is not just about improved brain power.Experiments conducted in 2013 by the Surrey Sleep Centre and the BBC showed a link between an extra hour in bed and genetic expression that helps protect against illnesses such as cancer，diabetes and stress.Blood tests revealed that genes associated with processes such as inflammation，immune response and response to stress became more active for those who had less sleep.
Meanwhile，other studies have linked extra sleep time to a lower risk of heart disease.A 2008 study published in the Journal of the American Medical Association showed that adults who slept for seven hours a night had a lower chance of having calcium deposits in their arteries than adults who had only six hours of sleep.Another study found that getting an extra hour of sleep significantly improved blood pressure levels among people with hypertension or pre-hypertension.
Daylight saving time has also been linked to heart attacks.In a study published in the British Medical Journal in 2014，Amneet Sandhu of the University of Colorado reported a 24% increase in heart attack admissions at hospitals in Michigan from 2010 to 2013 on the Monday after the clocks went forward in spring，when compared with other Mondays throughout the year.In contrast，he noted a 21% decrease in heart attacks on the Tuesday in the same hospitals after the clocks moved an hour back in autumn.
1.The text is mainly about____.
[A] the historical origin of the DST
[B] sleep and the brain's learning ability
[C] the physical harms of sleeping less
[D] the benefits of getting extra sleep
2.“Mental agility tasks”are those which____.
[A] must be accomplished with mental power
[B] take the brain much effort to perform
[C] the brain accomplishes during sleep
[D] have to be performed with electric devices
3.It can be inferred that genes in those who sleep less____.
[A] are busier in fighting stress
[B] are easily affected by diseases
[C] boost the immune system
[D] protect people from diseases
4.Extra sleep reduces the risk of heart disease by____.
[A] lessening the chances of hypertension
[B] reducing calcium deposits in the blood
[C] decreasing the chances of heart attacks
[D] reducing the patients’ blood pressure
5.The studies do not show that less sleep is directly linked to____.
[A] less mental power
[B] more active immune response
[C] more likelihood of hypertension
[D] more chances of heart attack
考研必备词汇
其他词汇
1.Greenwich mean time（GMT） 格林尼治标准时间
2.spindle 纺锤状波
3.inflammation 炎症
疑难长句注解
1.Experiments conducted in 2013...and stress.（第三段）
本句的主干结构是Experiments...showed a link between...and...，其中that引导的从句作定语修饰genetic expression，是指基因表达这一过程保护人免受疾病侵扰。本文有两个专业词汇，一个是genetic expression或gene expression，指the process by which information from a gene is used in the synthesis of a functional gene product.These products are often proteins.即来自一个基因的信息被用来合成功能性基因产品的过程，这些产品多为蛋白质。另一个是sleep spindles，指睡眠过程中脑电图上能看到的波状大脑电脉冲活动。
2.In a study published...the year.（第五段）
本句的主干结构是Amneet Sandhu...reported a 24% increase...，when compared with...。本句比较的是实行夏令时（将时间拨前一小时）时与不实行夏令时时心脏病的发作率。Michigan指美国密歇根州，hospitals in Michigan指这个州的医院。
译文
随着日光节约时制结束，英国将从夏时制换回到格林尼治标准时间，标志着更亮的早晨和更黑晚上的开端。现代日光节约时制有100多年的历史。它首先由安大略省奥瑞里市在1911—1912年引入。这个想法在第一次世界大战期间实现了大突破，当时德国在1916年4月30日引入日光节约时制，目的是减轻战时煤炭缺乏和空袭停电带来的困难。英国及其大部分盟友和许多欧洲中立国也很快加以效仿。
但是，夜晚多睡一小会儿可以改善记忆，增强学习能力。Matthew Walker教授是伯克利大学人类睡眠科学中心主任，他和他的研究小组在《现代生物学》上发表了一项研究，研究发现，在完成高难度记忆任务时，被允许多睡一会的受试者比不多睡的人完成得更好。研究者发现，大脑的学习能力与睡眠纺锤波（眼球快速运动睡眠期间产生的快速电脉冲）相关联。他们发现，睡眠少的人完成思维敏捷型任务有困难。
还不仅仅是大脑能力的改进。萨里大学睡眠研究中心和BBC在2013年的实验发现，多在床上睡一个小时与基因表达相关联，基因表达有助于保护人免受癌症、糖尿病和紧张等疾病的侵袭。血样测试显示，与发炎、免疫反应和应对压力等过程相关的基因在睡眠少的人身上更活跃。
同时，其他研究发现，多睡一些时间能降低患心脏病的概率。2008年发表于《美国医学会杂志》上的一项研究表明，睡七个小时的成人比只睡六个小时的成人动脉中遗留钙沉淀物的概率更低。另外一项研究发现，多睡一小时会显著改进患有高血压或有高血压前期症状的人的血压水平。
日光节约时制还与心脏病发作相关。在2014年发表在《英国医学杂志》上的一项研究中，科罗拉多州立大学的Amneet Sandhu报告说，在2010年—2013年，与全年的其他星期一相比，在春季时钟拨前之后的那个星期一，密歇根州医院接收的心脏病发作者增加了24%。他指出，相比之下，在秋季时钟拨后一个小时后的星期二，密歇根州医院接收的心脏病发作者少了21%。
TEXT 50
In the United States，the fight against infant mortality seemed slow but sure.But in recent years，progress in reducing overall infant mortality has stagnated.And for African Americans，we've actually lost ground，according to a study published this week in the Journal of the American Medical Association.This lack of progress is absolutely unacceptable.It's time to reenergize our efforts to reduce infant mortality.And this should start with improving the Republican-led plan to repeal and replace the Affordable Care Act.
For far too long，the United States has lagged behind the rest of the developed world in terms of infant mortality.Worse，the outcome of American babies shows stark racial inequalities.The preterm birth rate—which is associated with health complications for infants—is nearly 50 percent higher for black infants than white ones.
Researchers have had a difficult time pinning down exactly what's behind infant mortality trends，partly because it's impossible to conduct random trials to see the outcome of babies in different environmental settings.There's also a frustrating lack of understanding behind sudden infant death syndrome—the unexplained death of a baby，usually during sleep—which claimed the lives of 1,600 babies in 2015.But experts generally agree that the relatively high infant mortality rates in the United States have to do with poor nutrition among mothers，stress from poverty and smoking habits.Access to prenatal care，especially early ultrasounds，as well as family planning are also crucial elements in the mix.
Theoretically，this should be the sort of data informing policy from Republican lawmakers as they cobble together health-care legislation.But in reality，Republicans have proposed massive cuts to federal spending for Medicaid—which has long provided health care to low-income women and their children.As more Medicaid costs fall upon cash-strapped state budgets，the future of prenatal care to the nation's most vulnerable becomes fuzzy.
Researchers rightfully warn that infant mortality is not something that can be easily solved by policymakers in Washington，as there are deeper social and environmental issues at play.That's true，but our plateaued progress—especially our inequalities for babies of color—should startle everyone and must inform our debate on health care.
Health care is，and always has been，an issue fraught with political controversy.But infant mortality is an issue that should spark little disagreement：Protecting and caring for our most vulnerable—particularly，babies and pregnant women—should be among our highest priorities.Let's not give up on the progress we've made so far.
1.A recent study indicates that____.
[A] black preterm babies die at disproportionate rates
[B] the Republican-led initiative raises infant mortality
[C] the Affordable Care Act reduces infant death effectively
[D] racial discrimination starts after an infant is born
2.Which of the following is true in the third paragraph?
[A] The preterm babies’ environment is proved fatal to them.
[B] The cause of higher black baby mortality has not been identified.
[C] The infant death syndrome is caused by the environment.
[D] The noise is one of the causes of infant death syndrome.
3.The author's attitude to the Republican plan seems to be____.
[A] supportive
[B] tolerant
[C] critical
[D] contemptuous
4.The expression“plateaued progress”（Para. 5）refers to____.
[A] the policymakers’ indifference to black babies
[B] the stagnation in reducing baby mortality
[C] the unacceptability of the Republican proposal
[D] the failure in covering pregnant black women
5.The author concludes the discussion by insisting____.
[A] the Republican government should give priority to health care
[B] political debate should not be encouraged about health care
[C] health care is the most important thing for pregnant women
[D] further efforts should be made in reducing baby mortality
考研必备词汇
其他词汇
1.reenergize 重新注入活力
2.preterm 早产的
3.prenatal 出生前的
4.cobble 拼凑，拙劣地修补
5.cash-strapped 缺钱的，缺现金的
疑难长句注解
1.Researchers have had a difficult...settings.（第三段）
本句由主句和原因状语从句组成。在主句中，have a difficult time doing sth.是一个常见句式，词组pin down意为“明确说明，确认”，infant mortality trends指前两段提到的黑人婴儿死亡率高的趋势，what's behind指背后的原因。在从句中，trial指实验，outcome of babies和上一段中outcome of American babies意思一样，都指黑人婴儿死亡率高。这句话的大概意思是：由于很难用不同环境里出生的婴儿做活人实验，研究者到目前为止对造成黑人婴儿死亡率高的原因还不清楚。
2.Access to prenatal care...in the mix.（第三段）
主语Access to prenatal care指孕妇在孕期进行的各种医疗检查，early ultrasounds指怀孕初期的超声波检查，family planning指制订生育计划，mix指各种原因混杂在一起。
3.As more Medicaid costs...becomes fuzzy.（第四段）
本句由as（随着）引导的时间状语从句和主句组成。在从句中，Medicaid指美国的联邦医疗救助保险;词组fall upon意为“遭遇，（恰好）碰到”;cash-strapped指缺乏现金，这里笼统地指缺钱;state指美国的州。在主句中，the nation's most vulnerable这里指收入低的孕妇，所谓“变得模糊”这里指不确定。
译文
在美国，与婴儿死亡率的斗争进展缓慢，却取得了确定的成果。但是近年来，在降低婴儿总死亡率方面的进步陷入停滞状态。而且，《美国医学会杂志》本周登载的一项研究表明，对非裔美国人来说，我们实际上已经丢失了阵地。没有进步绝对是不可接受的。是我们应该重振士气，降低婴儿死亡率的时候了。而且，这一工作应该从改进共和党主导的撤销和代替平价医疗法案的计划做起。
在很长一段时间里，美国在降低婴儿死亡率上落后于其他发达国家。更糟糕的是，美国婴儿死亡率显示出明显的种族不平等。黑人婴儿中早产儿出生率——它与婴儿健康并发症相关联——比白人婴儿高出50%。
研究者很难确定造成婴儿死亡率趋势的准确原因，部分是因为无法进行随机的实验，来确定不同环境下婴儿的出生状态。对于突发的婴儿死亡综合征也令人沮丧地缺乏了解——这些婴儿通常在睡眠过程中莫名其妙地死亡，这种方式的死亡在2015年夺去了1600个婴儿的性命。但是，专家们通常认为，美国相对高的婴儿死亡率与母亲的营养不良、贫困压力和抽烟习惯有关。胎儿期医疗——特别是早期超声波检查，还有家庭计划等也是各种复杂原因中的关键因素。
从理论上来讲，在共和党议员罗织与健康相关的立法时，这应该是他们制定政策的数据信息基础。但是事实上，他们却提议联邦政府大幅地削减医疗保险和补助计划，而该计划长期以来为低收入妇女及其孩子提供着健康医疗保障。随着更多医疗保险和补助计划遭遇各州紧张的预算，美国最容易受到伤害人群的孕期护理的未来变得更加扑朔迷离。
研究者提出合理的警告：婴儿死亡率不是华盛顿的政策制定者能够很容易解决的问题，因为其中有更深的社会和环境问题在起作用。这当然是对的，但是我们停滞的进步——特别是在有色人种婴儿死亡率上存在的不平衡——应该引起每个人的注意，必须在有关健康医疗的辩论中得以体现。
健康医疗是——而且一直是充满政治争议的一个问题。但是婴儿死亡率不应该是一个引起争议的问题：保护和照料我们最弱小的人群——特别是婴儿和孕妇应该是我们工作的重中之重。让我们沿着迄今为止已经取得的进步继续前行！
TEXT 51
When we get the flu，we feel miserable. We swallow pain relievers，drink lots of tea，gulp down chicken soup. None of these treatments actually eradicates the flu virus itself; our immune system eventually takes care of that. Instead，these remedies make us feel better by alleviating the symptoms.
Yet while scientists have carefully chronicled the damage that the immune system can wreak on the body，they have paid much less attention to the mechanisms in place to repair it. “We spend a lot of our time figuring out how to stop the disease，but the real problem is how to get better，how to recover，” said David Schneider，an immunologist at Stanford University. “It's possible that getting better is a different thing，not just the reverse of getting sick.”
Schneider and others have begun to study the recovery process on its own，arguing that it is just as essential a component of the immune system as the body's attempts to eradicate foreign pathogens. They have divided the immune response into two basic categories：the traditional part，dubbed resistance，which fights the pathogen itself; and the less-studied part，called tolerance，which aims to curb or repair the damage inflicted by the pathogen or by resistance mechanisms. The research that they have published in the last few years hints that tolerance may be a crucial factor in whether individuals will survive infections such as malaria，cholera，and sepsis.
The sickle-celltrait boosts tolerance to malaria by enhancing the body's existing tools for dealing with stress. By better understanding these tolerance mechanisms，we can figure out new ways to enhance them. Schneider hopes that a similar approach will one day help predict whether a patient infected with the malaria parasite or another microbe will get better with moderate treatment or get worse and need more aggressive treatment. It's a completely different way of perceiving how a pathogen causes disease，and it will have huge implications for how we treat disease.
A Portugal immunologist Soares hopes that by better understanding these tolerance mechanisms，we can figure out new ways to enhance them. Indeed，the researchers have found that studying tolerance can point to quite unexpected avenues for drug development. Sepsis，for example，develops when the immune system spirals out of control and releases a flood of inflammatory cytokine molecules. That flood damages blood vessels and other tissues. The fatality rate for severe sepsis，in fact，is a startling 28 to 50 percent. “It seems to us and others to be a clear case of disrupted tolerance that can't be solved with antibiotics，” Soares said.
1.The flu virus can be driven away by_____.
[A] pain relieving medicine
[B] the immune system
[C] symptom-easing treatments
[D] combined treatments
2.Schneider puts more emphasis on_____.
[A] the process of recovering
[B] the treatment of the flu
[C] the process of getting sick
[D] the damage to the immune system
3.The tolerance mechanism helps recovery by_____.
[A] driving the virus out of the body
[B] killing the virus where it finds it
[C] boosting the immune system
[D] restricting the damage of the virus
4.Studying the tolerance mechanism may help us_____.
[A] speed up the recovery of our body
[B] eradicate such diseases like sepsis
[C] predict the kind of treatment applicable
[D] enhance the effect of traditional treatments
5.The studies of Schneider and others offer_____.
[A] a new medical science of disease recovery
[B] new ways of protecting the immune system
[C] new ways to kill disease-causing virus
[D] new perspectives on aggressive treatment
考研必备词汇
其他词汇
1.pain reliever 止疼药
2.immunologist 免疫学家
3.pathogen 病原体
4.cholera 霍乱
5.sepsis 脓毒症
6.sickle-cell 镰状细胞
7.Portugal 葡萄牙
8.inflammatory 发炎的
9.cytokine 细胞因子
疑难长句注解
Schneider and others...pathogens. （第三段）
句中study the recovery process on its own指专门研究恢复过程，just as...as意为“与……完全一样”，immune system指“免疫系统”，foreign此处意为“外来的”。
译文
患流感时，我们感觉难受。我们吞下止疼药，喝很多茶，喝大量鸡汤。这些治疗办法实际上都不能消除流感病毒本身——我们的免疫系统最终能消除它。相反，这些方法只能通过减轻症状来使得我们感觉好一些。
可是，虽然科学家仔细记录了免疫系统对身体的损害，他们却对修复免疫系统的机制重视得远远不够。David Schneider是斯坦福大学免疫学家，他指出，“我们花很多时间想搞清楚如何治好流感，但是真正的问题是如何好起来——如何康复。好起来可能是一个不同的过程，不仅仅等于得病的反面。”
Schneider和其他人已经开始研究康复过程本身，他们指出，随着身体试图消除外来病原体，康复过程成为免疫系统一个基本组成部分。他们把免疫系统的反应分作两个基本类别：一是传统部分，叫抵御过程，它抗击病原体；另一个研究少的部分叫耐受性，它旨在减少或修复病原体或抵御机制造成的损伤。他们在过去几年里发表的研究暗示，耐受性可能是一个关键因素，帮助人克服疟疾、霍乱和脓毒症等感染疾病得以生存。
镰状细胞素质增强身体现有工具应对压力的能力，以此增强对疟疾的耐受性。通过更好地了解这些耐受性机制，我们可以弄清增强它们的新方法。Schneider希望，类似的方法有一天将帮助预测，感染了疟疾病毒或其他病毒的病人是否能在接受有限治疗后好起来或者病情变坏，他是否需要更高强度的治疗。这是认识病原体怎样导致疾病的完全不同的方法，对我们治疗疾病具有重大意义。
葡萄牙免疫学家Soares希望，通过更好地了解这些耐受性机制，我们可以找出增强它们的新方法。的确，研究者已经发现，对耐受性的研究可以导向意想不到的药物研制途径。比如说，当免疫系统失控，并释放出大量发炎细胞素分子时，脓毒症就会发生。这些东西损伤血管和其他组织。事实上，严重的脓毒症的致死率达到令人吃惊的28%-50%。Soares说，“在我们和其他人看来，这显然是耐受性遭到损坏的案例，用抗生素解决不了问题。”
TEXT 52
Visit any major urban centre today and you are likely to be confronted with hundreds of people walking with their heads down as they fiddle with their mobile phones. But the phenomenon is not just irritating，it is actually changing the way people walk，according to scientists. Researchers at the University of Delaware asked 22 volunteers to dial a number on their mobile phone while walking. The walkers wore 62 reflective markers to measure knee flexion，hip movement and leg swing. The experiment showed that when distracted by dialling numbers，the volunteers began to walk with strange exaggerated strides，their knees bending to peak position on each step，and their ankles fully flexed，as if to give themselves as much chance as possible at stepping over tripping hazards.
The researchers say that people unconsciously adopt the posture because their body senses that they are at greater risk of falling over. The large，exaggerated movements potentially help them to negotiate crowds and compensate for their diminished vision. First author Kelly Seymour of the University of Delaware said：“Dual tasking resulted in increased stride width in our participants. This may represent compensation for a feeling of instability during dual task walking by increasing the base of support.” The researchers found that there were few mistakes in number dialling during the experiment which suggests that participants were prioritising dialling over walking.
A recent study by the University of Bath found that texters had developed a protective shuffle that prevents them bumping into obstacles，or tripping over hazards. They discovered that it took those texting 26 per cent longer to complete a walking task compared to those who were not distracted by their phones. However，the new research sought to find out how gait changed when people could not slow down. Gait speed is typically reduced when individuals simultaneously perform other tasks. However，in today's fast-paced world individuals are often rushed and do not choose to slow their gait speed. An increase in step width is characteristic of cautious gait，correlated with fear of falling.
The problem of text-walkers has become such a problem that last year Antwerp in Belgium brought in “text walking lanes” so that they do not irritate or endanger other pedestrians. The scheme is the brainchild of a local mobile phone business，Mlab，which says many smartphones are broken in collisions between pedestrians. The National Geographic TV channel launched a similar initiative on a smaller scale in Washington，but many walkers ignored the markings，although some took out their mobiles to photograph the lane markings on the pavement.
1.The researchers found that number-dialing walkers_____.
[A] walked in slower gaits than usual
[B] pondered only briefly over the numbers
[C] changed their gaits to increase stability
[D] were constantly tripped over obstacles
2.According to Seymour，exaggerated strides_____.
[A] prevented people from falling over
[B] guaranteed people dialed the correct numbers
[C] gave people an increased sense of instability
[D] made people walk in more cautious ways
3.Dual tasking resulted in all the following except_____.
[A] increased possibility of tripping over
[B] vision being limited by looking down
[C] less chance to talk with other pedestrians
[D] greater likelihood of bumping into people
4.Today's dual taskers who try to avoid falling_____.
[A] speed up their walking
[B] increase their stride width
[C] slow down their gait speed
[D] shift attention to walking
5.What happens in Washington and Antwerp?
[A] More people bump into each other and broke phones.
[B] Dual tasking has become a more serious problem.
[C] Special areas are reserved for phone photographing.
[D] Dual-tasking walkers can walk on special lanes.
考研必备词汇
其他词汇
1.flexion 弯曲（部位）
2.flex 弯曲
3.shuffle 拖着脚走
4.brainchild 脑力劳动的产物
疑难长句注解
1.The experiment showed...hazards. （第一段）
句中volunteers指自愿参加实验的人，peak是动词，这里指将膝盖尽量抬高；step over意为“迈过”，tripping意为“绊倒”，hazards指障碍物或其他危险。
2.The problem of text-walkers...other pedestrians. （第四段）
句中，text-walkers指边走路边用手机发短信的人，Antwerp是比利时的一座城市，bring in意为“提出（想法等），引进”，text walking lane指专门为边走路边发短信的人留出的道。
译文
你现在去任何一个大城市中心，都可能遇到成百上千一边摆弄手机一边低头走路的人。但是这种现象不仅仅是让人不安，科学家说，它实际上改变了人行走的方式。特拉华州立大学的研究人员要求22个志愿者走路时拨打手机号码。走路者身上戴着62个反射点，测量其膝部弯曲度、胯部运动和腿部摆动。实验表明，当志愿者因拨号码分心时，他们开始用奇怪的、夸大的步伐行走，他们的膝部弯曲，在走一步时抬高膝盖位置，他们的脚踝得到完全的弯曲，似乎尽可能跨过绊倒他们的障碍物。
研究者说，人们无意识地采用某种姿势，是因为他们的身体感觉他们有更大的摔倒的危险。更大的、夸张的动作能帮助他们躲避人群，弥补有限的视野产生的不足。文章第一作者特拉华大学的Kelly Seymour说，“同时做两件事使参与者步幅加大。这可能代表对不稳定感的补偿，这样做在边走边做其他事情时增加了支撑的根基。”研究者发现，在实验过程中，很少有人拨错号码，这表明参与者把拨号码放到了走路之上。
巴斯大学的一项新研究发现，发短信的人已经形成一种保护性步伐，防止他们碰到障碍物或被危险物绊倒。他们发现，这些发短信的人需要多26%的时间来完成不因手机分心的人完成的行走任务。然而，这项新的研究试图发现人们不能放慢脚步时如何改变步伐。当人同时做其他事情时，步伐速度通常降低。然而，在今天这个快节奏的世界里，人经常被催促，无法选择放慢步伐速度。步幅加大通常是步履谨慎的表现，与害怕摔倒有关。
发短信的行人的问题已经成为如此严重的问题，以至于去年比利时的安特卫普市设计了“短信发送行人专道”，以便这些人不打扰或威胁到其他行人。这项设计是当地一家手机商Mlab发明的产物，它说，由于行人之间的碰撞，很多手机被摔坏。国家地理电视频道在华盛顿市发起一场小规模的类似动议，但是许多行人忽视了地上的标记，虽然有些人拿出手机给人行道上的道路标志拍照。
TEXT 53
In the past four decades, American doctors have lost the status they used to enjoy. Today medicine is just another profession, and doctors have become like everybody else: insecure, discontented and anxious about the future. In surveys, a majority of doctors express diminished enthusiasm for medicine and say they would discourage a friend or family member from entering the profession. American doctors are suffering from a collective malaise.
The discontent is alarming, but how did we get to this point? To some degree, doctors themselves are at fault. In the halcyon days of the mid-20th century, American medicine was also in a golden age. Life expectancy increased sharply, aided by such triumphs of medical science as polio vaccination and heart-lung bypass. They were prospering under the private fee-for-service model. After Medicare was introduced in 1965 as a social safety net for the elderly, doctors' salaries actually increased as more people sought medical care.
But as doctors profited, they were increasingly perceived as bilking the system. Year after year, health-care spending grew faster than the U.S. economy as a whole. Meanwhile, reports of waste and fraud were rampant. A congressional investigation found that in 1974, surgeons performed 2.4 million unnecessary operations.
Public opinion of doctors shifted distinctly downward too. Doctors were no longer unquestioningly exalted. On television, physicians were portrayed as more human or professionally and personally fallible. More recent surveys have shown that 30% to 40% of practicing physicians wouldn't choose to enter the medical profession if they were deciding on a career again.
The growing discontent has serious consequences for patients.One is a looming shortage of doctors, especially in primary care, which has the lowest reimbursement of all the medical specialties and probably has the most dissatisfied practitioners. Try getting a timely appointment with your family doctor; in some parts of the country, it is next to impossible. Perhaps the most serious downside, however, is that unhappy doctors make for unhappy patients. Patients today are increasingly disenchanted with a medical system that is often indifferent to their needs. For many of us, it is rare to find a primary physician who can remember us from visit to visit, let alone come to know us in depth or with any relevancy.
Of course, doctors aren't the only professionals who are unhappy today. Many professions, including law and teaching, have become constrained by corporate structures, resulting in loss of autonomy, status, and respect. But as the Princeton sociologist Paul Starr writes, for most of the 20th century, medicine was “the heroic exception that sustained the waning tradition of independent professionalism.” It is an exception whose time has expired.
1.Which of the following is not a “collective malaise” of American doctors?
[A] Feeling self-conceited about their profession.
[B] Feeling indifferent to their patients' demands.
[C] Feeling uncomfortable in their profession.
[D] Feeling less assertive about their future.
2.After the Medicare was introduced, doctors_____.
[A] instilled more passion into their profession
[B] were accused of taking advantage of the system
[C] had to receive congressional fraud investigation
[D] were unwilling to discard the fee-for-service model
3.A shortage of primary care doctors is most serious because_____.
[A] they benefit the least from Medicare
[B] they are on the verge of retiring
[C] they are not paid satisfactorily
[D] they shoulder the heaviest burden
4.Discontent on doctors' part hurts patients with_____.
[A] earlier retirement of qualified boomer physicians
[B] doctors' impatience with patients' disenchantment
[C] patients' reluctance to visit doctors day in and day out
[D] doctors' ignorance of patients' medical conditions
5.The author concludes the discussion by saying_____.
[A] medical profession will restore its past glorious days
[B] medicine will lose its status as an autonomous profession
[C] medical profession will sustain independent professionalism
[D] physicians should not be subjected to professional pressures
考研必备词汇
其他词汇
1.malaise 生病，不适
2.halcyon 繁荣的，兴盛的
3.polio 小儿麻痹症
4.bypass 心脏搭桥手术
5.bilk 骗取，欺骗
疑难长句注解
1.One is a looming shortage...practitioners.（第五段）
本句中，looming意为“迫在眉睫的，即将发生的”，reimbursement意为“补偿，酬金”，medical specialties指医学各专科，如神经外科、小儿科等，practitioner指医生。
2.For many of us, it is rare...any relevancy.（第五段）
本句中，primary physician指从事primary care的医生，visit指病人去医院就诊，let alone意为“更不用说”，in depth意为“深入地”，with any relevancy指把病人每次就诊的相关信息联系起来。
3.Many professions...and respect.（第六段）
本句中，be constrained by corporate structures指被保险公司等控制或限制，autonomy, status and respect指医疗行业的自主、地位和尊严。
4.But as the Princeton sociologist...professionalism.（第六段）
本句中，independent professionalism指上一句提到的autonomy，即独立的职业精神，如不受金钱等外在因素影响的人道主义精神。
译文
在过去40年里，美国医生丢失了他们曾经拥有的地位。今天，医疗行业只不过是另一个行业，医生跟所有人没有区别：没安全感，不满意，担忧未来。在调查中，大多数医生表达了对医疗行业更少的热情，他们说，他们会劝告朋友和家人勿进入这个行业。美国医生患上了一种集体病。
这种不满令人震惊，但是我们怎么会走到这一步呢？在某种程度上，医生自己难辞其咎。在20世纪中期那些幸福的日子里，美国医学行业处于黄金时代。在小儿麻痹症疫苗和心脏搭桥手术等医疗科学成就的助推下，人的平均寿命急剧增长。他们在按服务收费的私有制模式下感到春风得意。在1965年，医疗保障被引入，成为老年人的社会保障网，更多的人寻求医疗护理，医生的薪水实际上增加了。
但是，随着医生挣钱越多，他们越来越被看作从医疗保障体制中渔利的人。健康医疗开支年复一年地超过总体美国经济的增长。同时，对浪费和欺诈的报道满天飞。国会的一项调查发现，在1974年，外科医生做了240万次没必要做的手术。
民众对医生的看法也明显急转直下。医生不再理所当然地被高抬。在电视上，医生被刻画为普通人的形象，在职业上和个人生活上都可能犯错误。更新的调查表明，在行医的医生中有30%~40%的人表示，如果有重选职业的机会，他们不会选择进入医疗行业。
越来越多的不满对病人产生严重影响。一个影响是将很快出现医生的短缺，特别是在初级医疗领域，这是医学专业中收入最低，也许是行医者最不满意的领域。想让你的家庭医生按时赴约，在美国一些地区简直是不可能的。然而，最严重的负面影响也许是医生的不满导致病人的不满。今天，病人越来越对医疗体制失望，因为它对病人的需要置之不理。对我们许多人来说，很少能找到记得来看病的病人的初级医疗医生，更不要说深度熟知我们，了解我们相关信息的医生了。
当然，医生不是今天唯一不幸福的从业人员。许多职业的人，包括法律和教学行业的人，受到了公司结构的约束，结果造成了自主、地位和尊严的丧失。但是，普林斯顿大学社会学家Paul Starr写道，在20世纪大部分时间里，医疗行业“作为一个例外英勇地维系着衰落的独立的职业精神传统”。这一例外现在已经到期。
TEXT 54
American scientists have located a virus that attacks human DNA, which may cause those infected to be less intelligent, impairing brain activity, learning and memory. Researchers from Johns Hopkins School of Medicine and the University of Nebraska have identified traces of an algal virus, known as ATCV-1, which appeared to lessen mental capacity.
The researchers had originally been working on an unrelated study into throat microbes when they unexpectedly located traces of ATCV-1 in human DNA samples. At first the research team, led by Dr Robert Yolken of Johns Hopkins, didn't know what ATCV-1 was, and had to carry out a database search to find out more about the unknown virus. ATCV-1 typically infects a species of green algae found in lakes and rivers, and has not previously been known to infect humans. However, when Yolken's team screened a group of 92 healthy volunteers who were taking part in a study on cognitive function, the virus was found to be present in 43.5% of them.
According to the study, those infected with the virus performed around 10% worse on tests analysing visual processing speeds. In one test, infected volunteers were slower to draw a line connecting a sequence of numbers randomly distributed on a page than their uninfected counterparts. The researchers found that the presence of the virus was linked to lower attention spans and decreased spatial awareness, and a “statistically significant decrease in the performance on cognitive assessments of visual processing and visual motor speed”. Researchers found no connection between slower brain function and variables such as differences in sex, education level, income, race, and even cigarette smoking.
The team carried out further tests, in which they injected uninfected and infected green algae into the mouths of mice and put them through a series of lab tests. The results revealed that infected animals took 10% longer to find their way out of mazes and spent 20% less time exploring new objects than uninfected mice, conforming to the findings amongst human volunteers. According to the study, the virus appeared to impair the “learning, memory formation, and the immune response to viral exposure” of the mice.
Professor James L. Van Etten, a member of the research team, said that little is currently known about how the virus could be transmitted to humans in such abundance, but that they had no reason to believe that the viruses are contagious among people or animals. “My best guess is that these viruses may infect another microorganism besides the algae that we have been studying. This other microorganism may be the way that the virus gets into the throat,” he added.
1.American researchers believe that_____.
[A] impairing the brain reduces mental power
[B] memory and intelligence are closely linked
[C] they have found new uses for green algae
[D] they have discovered “stupidity virus”
2.The researchers accidentally located the virus_____.
[A] in human throats
[B] in lakes and rivers
[C] in mice being studied
[D] in a virus database
3.Those infected with the virus had worse performance in_____.
[A] speeding up information-processing
[B] coordinating the eyes and limbs
[C] finding connection between statistics
[D] identifying important variables
4.Further experiments indicate that infected mice_____.
[A] refused to eat green algae
[B] resisted virus injection
[C] became less curious
[D] infected human volunteers
5.Van Etten said that the team has yet to identify_____.
[A] any potential indicators of the virus's presence in humans
[B] the way green algae pass on the virus to other microorganisms
[C] the difference of the viruses affecting humans and mice
[D] the way the viruses impair the cognitive function of humans
考研必备词汇
其他词汇
alga （pl. algae） 水藻，藻类
疑难长句注解
1.The researchers found that...motor speed.（第三段）
在本句的宾语从句中，介词to后面有三个并列的宾语，其中lower attention spans指注意力持续时间更短，decreased spatial awareness指空间感觉下降。在stastistically...motor speed这个宾语中，visual processing指视觉处理能力，visual motor speed指视觉与运动肌的协调能力，如眼睛看到某物后四肢是否能迅速做出反应，这两种能力都属于认知能力的范围，assessment指对这两种能力进行测试，performance指测试的结果或成绩。因此，statistically significant decrease指测试统计结果显示，这两种能力都有显著减弱。
2.The results revealed that...human volunteers.（第四段）
这里所谓花更少时间exploring new objects指它们的好奇心下降，对事物缺乏新鲜感，conforming to the findings among human volunteers指与第四段提到的那项研究的结果相符。
译文
美国科学家已经找到了一种攻击人类DNA的病毒，它可能使感染者智商变低，损伤大脑的活动、学习和记忆能力。约翰霍普金斯大学医学院和内布拉斯加州立大学的研究者找到了一种藻类病毒痕迹，名叫ATCV-1，它似乎降低了心智能力。
研究者起初在对咽喉微生物进行另一项研究，这时，他们出乎意料地在人类DNA采样中找到了ATCV-1的痕迹。研究组由约翰霍普金斯大学Robert Yolken医生领导，起初，他们不知道ATCV-1是什么，所以为了更多地了解这种鲜为人知的病毒，他们不得不在数据库中查询。ATCV-1通常感染湖和河中的一种绿藻，以前没有感染人的记录。然而，在一项对认知功能的研究中，当Yolken的研究小组筛查由92位健康志愿者构成的研究对象时，他们发现这种病毒存在于43.5%的人身上。
根据这项研究，那些感染这种病毒的人在涉及分析视觉处理速度的测试中大约慢10%。在一次测验中，受感染的志愿者被要求画线连接一系列数字，这些数字随机分布在一张纸上，他们连线的速度低于未受感染的人。研究者发现，病毒的存在与下列三种现象有关联：注意力时段更短，空间意识降低，“在对视觉处理和视觉—运动速度所做的认知测验成绩从统计学上来看显著降低”。研究者没有发现更慢的大脑功能与各种变量之间的关联，这些变量包括性别、教育水平、收入、种族甚至吸烟等方面的差别。
研究组又做了进一步的实验。他们把未受感染和已受感染的绿藻注入老鼠嘴里，然后对它们进行一系列实验。结果显示，与未受感染的老鼠相比，受感染的老鼠需要多10%的时间才能走出迷宫，少花20%的时间探索新物体，这一发现与在人类志愿者身上的发现相一致。这项研究表明，这种病毒似乎损伤了老鼠的“学习、形成记忆和抵御病毒的免疫力”。
James L.Van Etten教授是研究成员，他说，目前，对于病毒怎样可能以如此大的量传给人，还知之甚少，但是，他们没理由认为病毒在人或动物之间有传染性。他补充说：“我能做的最好猜测是，除了我们研究的藻类以外，这些病毒可能感染了另外的微生物。病毒可能是通过这种微生物进入咽喉。”
TEXT 55
Obesity harms most organs in the body, and new research suggests the brain is no exception. What's more, the researchers found that getting rid of excess fat actually improves brain function, reversing the ill effects of the extra weight. The new study, which focused on people who underwent bariatric surgery, found that the procedure had positive effects on the brain, but other research has shown that less invasive weight loss strategies, like exercise, can also reverse brain damage thought to be related to body fat.
In a recent study, a team of researchers looked at 17 obese women prior to bariatric surgery and found that their brains metabolized sugars faster than the brains of a control group of women at a normal weight. The women underwent cognitive function tests before their surgery as well as after. The results show that after surgery, the obese women showed improvement in the troubling brain activity seen prior to going under the knife, and they performed better on their cognitive function tests—especially in the area of executive function, which is used during planning and organization. The findings suggest that the fat loss reverses its bad effects on the brain.
Researchers are still trying to understand the exact effects of body fat on the brain, but one theory is that it's a chain-of-events-type of scenario. For instance, insulin resistance has become linked to diseases like Alzheimer's. Insulin resistance is a metabolic disorder, that can be brought on by obesity. Other theories have to do with the effects of certain kinds of fat. The National Institutes of Health （NIH） points out that visceral fat, the most damaging type of body fat, ups a person's likelihood of developing insulin resistance, and on top of that, belly fat can produce stress hormones that can also hinder cognition. Other research has shown that the stress hormones are tied to hunger signaling, and those disruptions can alter a person's sense of hunger and fullness and can contribute to obesity. “The more we understand about body fat, the clearer it becomes that belly fat is its own disease-generating organism,” said Dr.Lenore Launer in an NIH statement.
Inflammation continues to be fingered as a culprit in the link between body fat and a variety of disorders, which include brain-related diseases, and even depression. Body fat is thought to create substances that cause inflammation, and that could be at least one of the primary ways it irritates the brain. The bottom line is that excess body fat has a laundry list of effects on the body, and none of them are good.
1.The new research suggests that_____.
[A] weight loss surgery reverses negative effects on the brain
[B] bariatric surgery does not produce more good than exercise
[C] damage to the brain will cause obesity if not properly treated
[D] surgery is only necessary when a person becomes overweight
2.Having too much fat harms all of the following EXCEPT.
[A] cognitive ability
[B] school performance
[C] physical health
[D] organizing ability
3.Dr.Lenore Launer at NIH believes that_____.
[A] insulin resistance increases stress hormone levels
[B] belly fat is the most damaging type of body fat
[C] belly fat constantly generates diseases inside the belly
[D] certain kinds of fat are responsible for cognitive damage
4.Before the new finding, it was believed that_____.
[A] women were more likely to become overweight
[B] the executive function was related to visceral fat
[C] inflammation was the major cause of brain disorders
[D] body fat had a list of positive effects on the brain
5.The text is written to explain_____.
[A] what weight loss does to your brain
[B] how belly fat becomes stress hormone
[C] how belly fat becomes disease-generating
[D] what diseases weight gain may cause
考研必备词汇
其他词汇
1.bariatric 减肥的，减重的
2.insulin 胰岛素
3.visceral 内脏的，内心的
4.inflammation 发炎；着火
疑难长句注解
1.The new study...body fat.（第一段）
词组bariatric surgery指治疗肥胖症的手术，the procedure指bariatric surgery，即实施这种手术不仅对身体有好处，而且能提高智力；less invasive weight loss strategies指手术之外的减肥方法，reverse brain damage指纠正对大脑的伤害，thought to be related to body fat是分词短语作定语，修饰damage。
2.The results show that...organization.（第二段）
本句中，the troubling brain activity指第一句中提到的their brains metabolized sugars faster，分词短语seen prior to going under the knife作定语，修饰the troubling brain activity，其中going under the knife指接受手术。所谓“执行功能”，指大脑制订并实施计划的能力。
3.The National Institutes of Health...hinder cognition.（第三段）
在that引导的宾语从句中，主干结构是visceral fat...ups a person's likelihood，其中up是动词，意为“增加，提升”，develop意为“患（病）”。介词词组on top of意为“在……之上（之外）”，经常表示最不好的方面。
4.Other research has shown...to obesity.（第三段）
本句中，be tied to意为“与……相关”，hunger signaling指体内控制饥饿感的信号，those disruptions指体内脂肪或腹部脂肪对胰岛素和激素的破坏，使之变得不正常。
译文
肥胖症对身体的大部分器官有害，新研究表明，大脑也不例外。更重要的是，研究者发现，去除多余的脂肪能实际改进大脑的功能，消除超重产生的坏影响。这项新研究集中于经历过肥胖症手术治疗的人，它发现治疗过程对大脑产生积极影响，但是其他研究证明，像锻炼这样的非侵入减肥策略，也能消除被认为由身体脂肪引起的大脑损伤。
在最新一项研究中，一组研究者在肥胖手术治疗前研究了17个肥胖妇女，他们发现，她们的大脑比作为对照组的正常体重的女人糖分的代谢速度快。这些女人在手术前后经过了认知功能测试。测试结果表明，手术后，肥胖女人改进了其大脑活动，不像手术前观察到的那样混乱，而且她们在认知功能测试上取得了更好成绩——特别是在执行功能领域，这是做计划和组织工作时使用的领域。这些发现表明，减少脂肪能消除它对大脑的不良影响。
研究者还在试图理解身体脂肪对大脑的确切影响，但是一种理论认为，这是一种链锁关系的情景。比如说，胰岛素抗性与老年痴呆症这样的疾病相联系，它是一种代谢紊乱疾病，可以由肥胖导致。其他理论涉及某些种类的脂肪的影响。国家卫生研究院指出，内脏脂肪是身体脂肪中破坏作用最大的一种，它提高了人形成胰岛素抗性的可能性，更重要的是，腹部脂肪能产生压力激素，也能阻碍认知。其他研究证明，压力激素与饥饿信号有关，这些破坏能改变人的饥饿感和吃饱的感觉，能导致肥胖症。在国家卫生研究院发表的一份声明中Lenore Launer博士说：“我们对身体脂肪了解得越多，我们就越清楚地认识到，腹部脂肪就是产生身体疾病的组织。”
在身体脂肪与各种紊乱症（包括大脑疾病、甚至抑郁症）的联系中，炎症一直被当作罪魁祸首。身体脂肪被认为是产生了引起炎症的物质，这至少可能是扰乱大脑的主要方式之一。一个底线是，多余的身体脂肪对身体有一大串影响，其中没有一个是好影响。