首页
外语
计算机
考研
公务员
职业资格
财经
工程
司法
医学
专升本
自考
实用职业技能
登录
外语
We sometimes think humans are uniquely vulnerable to anxiety, but stress seems to affect the immune defenses of lower animals to
We sometimes think humans are uniquely vulnerable to anxiety, but stress seems to affect the immune defenses of lower animals to
admin
2018-05-11
64
问题
We sometimes think humans are uniquely vulnerable to anxiety, but stress seems to affect the immune defenses of lower animals too. In one experiment, for example, behavioral immunologist (免疫学家 ) Mark Laudenslager, at the University of Denver, gave mild electric shocks to 24 rats. Half the animals could switch off the current by turning a wheel in their enclosure, while the other half could not. The rats in the two groups were paired so that each time one rat turned the wheel it protected both itself and its helpless partner from the shock. Laudenslager found that the immune response was depressed below normal in the helpless rats but not in those that could turn off the electricity. What he has demonstrated, he believes, is that lack of control over an event, not the experience itself, is what weakens the immune system.
Other researchers agree. Jay Weiss, a psychologist at Duke University School of Medicine, has shown that animals who are allowed to control unpleasant stimuli don’t develop sleep disturbances or changes in brain chemistry typical of stressed rats. But if the animals are confronted with situations they have no control over, they later behave passively when faced with experiences they can control. Such findings reinforce psychologists’ suspicions that the experience or perception of helplessness is one of the most harmful factors in depression.
One of the most startling examples of how the mind can alter the immune response was discovered by chance. In 1975 psychologist Robert Ader at the University of Rochester School of Medicine conditioned (使形成条件反射) mice to avoid saccharin (糖精) by simultaneously feeding them the sweetener and injecting them with a drug that while suppressing their immune systems caused stomach upsets. Associating the saccharin with the stomach pains, the mice quickly learned to avoid the sweetener. In order to extinguish this dislike for the sweetener, Ader reexposed the animals to saccharin, this time without the drug, and was astonished to find that those mice that had received the highest amounts of sweetener during their earlier conditioning died. He could only speculate that he had so successfully conditioned the rats that saccharin alone now served to weaken their immune systems enough to kill them.
It can be concluded from the passage that the immune systems of animals ______.
选项
A、can be weakened by conditioning
B、can be suppressed by drug injections
C、can be affected by frequent doses of saccharin
D、can be altered by electric shocks
答案
A
解析
Ader采用一定的方法使老鼠形成条件反射,这种反射削弱了老鼠的免疫功能。根据以上分析,A与文中所表达的意思一致;B与原文意思相悖;服用糖精影响免疫系统,是针对Ader实验中的老鼠而言,并不是针对所有动物,C错;D与文中内容不符。
转载请注明原文地址:https://kaotiyun.com/show/IpT7777K
0
大学英语六级
相关试题推荐
A、Thepricesofitsshareswentdown.B、MostworkersinApplelosttheirjobs.C、Thecompanysufferedheavylosses.D、Thecompan
HowtoDuckCabinFeversandOtherAchesonaPlane?[A]Onthefirstlegofthisseason’sholidaytraveltour,Ihadthedelight
A、Theyprefercooltemperatures.B、Theycansurviveextremeconditions.C、Theyarevulnerabletoradiation.D、Theyhaveaverys
Itseemslogical:Collegegraduateshavelowerunemploymentandearnmorethanlesseducatedworkers,so,thethinkinggoes,the
Comparisonsweredrawnbetweenthedevelopmentoftelevisioninthe20thcenturyandthediffusionofprintinginthe15thand1
EatingOurYoung[A]AtFeltonvilleSchoolofArtsandSciences,amiddleschoolinapoorneighborhoodofPhiladelphia,thescho
传统中国装饰绳结,也就是我们所说的中国结(Chineseknot),是一种典型的中国本土艺术。这是一门独特的传统中国民间手工编织艺术,每个绳结只使用一根线,根据其形状和意义而命名。在中国,“结”意味着团结、友谊、和平、温暖和爱情等。中国结经常被用来表达良
Gettingbehindthewheelofacarcanbeanexcitingnewstepinateen’slife.Butalongwiththatexcitementcomesanew【B1】__
Gettingbehindthewheelofacarcanbeanexcitingnewstepinateen’slife.Butalongwiththatexcitementcomesanew【B1】__
A、Afewmonths.B、Afewdays.C、About21years.D、About5years.D
随机试题
物资检查和盘点是()过程中不可缺少的一项工作。
工作标准化的具体方式有()
从原始社会到资本主义社会,教育与生产劳动之间关系的历史演进过程是()
《医疗事故处理条例》施行时间是
根据《建筑施工组织设计规范》GB/T50502-2009,“合理安排施工顺序”属于施工组织设计中()的内容。
我独不解中国人何以于旧的状况那么______,于较新的机运是那么______;于已成之局那么委曲求全,于初兴之事就那么______。填入横线部分最恰当的一项是()。
小强正在专心地做地理拼图,亮亮从旁边走过。只听“哎哟”一声,亮亮的腿碰到了小强的课桌,把小强花很长时间做的拼图碰散了。小强一抬头,却发现亮亮正朝旁边的同学挤眉弄眼。由此,小强认为亮亮的行为是故意的,十分生气,给了亮亮一拳。试用攻击行为的社会信息加工模型解释
弟、妹对兄、姐履行扶养义务的条件包括()。
下列叙述中正确的是()。
Eatingfruitsandvegetableshasprovedhelpfulinpreventingvariouschronic(慢性的)illnesses.Doesthatmeanthemorethebetter?
最新回复
(
0
)