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
2019-06-23
31
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.
Laudenslager’s experiment showed that the immune system of those rats who could turn off the electricity _____.
选项
A、was strengthened
B、was not affected
C、was altered
D、was weakened
答案
B
解析
第1段第5句提到:Laudenslager发现那些无助的老鼠的免疫反应被削弱了,低于正常水平,而那些能切断电源的老鼠却没有。因此,B正确。
转载请注明原文地址:https://kaotiyun.com/show/KyX7777K
0
大学英语六级
相关试题推荐
A、Thosewhoknowhowtoprogramcomputers.B、Thosewhogetspecialaidfromtheirteachers.C、Thosewhoareveryhardworking.D、
A、Thepopulationwillincreaseuncontrollably.B、Peoplewillsufferfrommoreseriouslackoffood.C、800millionpeoplewilldi
A、TheroleofimmigrantsintheconstructionofAmericansociety.B、TheimportanceofofferingdiversecoursesinEuropeanhisto
A、Becauseitispowerfulandaggressive.B、Becauseit’sacompanionandprotectionbreed.C、Becausemostpeopleareafraidofit
A、Theygenerallyspentmoretimetogetherthanwhitepairs.B、Theymovedoutofthecollegedormsattheendofthesemester.C、
A、Blackfreshmenwithhighstandardizedtestscores.B、Blackstudentsfromfamilieswithlowincomes.C、Studentswhoareaccusto
A、Sleepinginanopenenvironment.B、Usingfuelinsteadofelectricity.C、Usingsmallandmovablegasgenerators.D、Short-termc
A、Toexplainthecausesofsynesthesia.B、Toprovethatsoundandcolorcanaffectaperson’smood.C、Todeterminewhetherorn
A、HowtoorderamealatMcDonald.B、Thehistoryofrestaurant.C、Twobrothers-MacandDickMcDonald.D、ThedevelopmentofMcDon
Forthispart,youareallowed30minutestowriteanessayonthetopic"Stress".Youcaneitheranalyzeitscausesorshareso
随机试题
下列关于项目评估方法的表述中,正确的有()。
庆大霉素不能与呋塞米合用的主要原因是两药合用后
属糖酵解途径关键酶的是
(司法试题)绿杨公司因严重资不抵债向法院申请破产,法院已经受理其申请。根据《破产法》的规定,在法院已经受理破产申请、尚未宣告绿杨公司破产之时,下列哪一项财产不构成债务人财产?()
现行宪法规定,自治区的自治条例和单行条例的审批权属于()。
负荷计算中描述错误的是()。
明敷的电缆不宜平行敷设于热力管道上部。当必须平行热力管道敷设,且电缆与热力管道之间无隔板防护时,其间距应为500mm。()
社会主义教育科学文化建设要解决的是
数据库系统其内部分为三级模式,即概念模式、内模式和外模式。其中,______是用户的数据视图,也就是用户所见到的数据模式。
Humanity’sprimaleffortstosystematizetheconceptsofsize,shapes,andnumberareusuallyregardedastheearliestmathemati
最新回复
(
0
)