CET6阅读通关班电子教材主讲：屠浩民欢迎使用新东方在线电子教材教材说明：本电子教材word文档下面的页码跟教材完全一样，学员只需根据老师说的多少页找到相应的页面学习即可。请提前预习、认真学习、及时复习，祝广大学子考试取得成功！新东方在线[www.koolearn.com]CET6通关班网络课堂电子教材系列阅读第一部分阅读理解全真试题Unit1PartⅡReadingComprehension(35minutes)Directions:Thereare4readingpassagesinthispart.Eachpassageisfollowedbysomequestionsorunfinishedstatements.ForeachofthemtherearefourchoicesmarkedA),B),C)andD).YoushoulddecideonthebestchoiceandmarkthecorrespondingletterontheAnswerSheetwithasinglelinethroughthecentre.Questions21to25arebasedonthefollowingpassage:Wesometimesthinkhumansareuniquelyvulnerabletoanxiety,butstressseemstoaffecttheimmunedefensesofloweranimalstoo.Inoneexperiment,forexample,behavioralimmunologist(免疫学家)MarkLaudenslager,attheUniversityofDenver,gavemildelectricshocksto24rats.Halftheanimalscouldswitchoffthecurrentbyturningawheelintheirenclosure,whiletheotherhalfcouldnot.Theratsinthetwogroupswerepairedsothateachtimeoneratturnedthewheelitprotectedbothitselfanditshelplesspartnerfromtheshock.Laudenslagerfoundthattheimmuneresponsewasdepressedbelownormalinthehelplessratsbutnotinthosethatcouldturnofftheelectricity.Whathehasdemonstrated,hebelieves,isthatlackofcontroloveranevent,nottheexperienceitself,iswhatweakenstheimmunesystem.Otherresearchersagree.JayWeiss,apsychologistatDukeUniversitySchoolofMedicine,hasshownthatanimalswhoareallowedtocontrolunpleasantstimulidon'tdevelopsleepdisturbancesorchangesinbrainchemistrytypicalofstressedrats.Butiftheanimalsareconfrontedwithsituationstheyhavenocontrolover,theylaterbehavepassivelywhenfacedwithexperiencestheycancontrol.Suchfindingsreinforcepsychologists'suspicionsthattheexperienceorperceptionofhelplessnessisoneofthemostharmfulfactorsindepression.Oneofthemoststartlingexamplesofhowthemindcanaltertheimmuneresponsewasdiscoveredbychance.In1975psychologistRobertAderattheUniversityofRochesterSchoolofMedicineconditioned(使形成条...
