英语_高中英语阅读理解精读荟萃(中级篇)3

-1-PassageOneTheAffectofElectricityonCancerCanelectricitycausecancer?Inasocietythatliterallyrunsonelectricpower,theveryideaseemspreposterous.Butformorethanadecade,agrowingbandofscientistsandjournalistshaspointedtostudiesthatseemtolinkexposuretoelectromagneticfieldswithincreasedriskofleukemiaandothermalignancies.Theimplicationsareunsettling,tosaytheleast,sinceeveryonecomesintocontactwithsuchfields,whicharegeneratedbyeverythingelectrical,frompowerlinesandantennastopersonalcomputersandmicro-waveovens.Becauseevidenceonthesubjectisinconclusiveandoftencontradictory,ithasbeenhardtodecidewhetherconcernaboutthehealtheffectsofelectricityislegitimate—ortheworstkindofparanoia.w*w*w*k*s*5*u*c*o*mNowthealarmistshavegainedsomequalifiedsupportfromtheU.S.EnvironmentalProtectionAgency.Intheexecutivesummaryofanewscientificreview,releasedindraftformlatelastweek,theEPAhasputforwardwhatamountstothemostseriousgovernmentwarningtodate.Theagencytentativelyconcludesthatscientificevidence“suggestsacasuallink”betweenextremelylow-frequencyelectromagneticfields—thosehavingverylongwave-lengths—andleukemia,lymphomaandbraincancer,WhilethereportfallsshortofclassifyingELFfieldsasprobablecarcinogens,itdoesidentifythecommon60-hertzmagneticfieldas“apossible,butnotproven,causeofcancerinhumans.”Thereportisnoreasontopanic—oreventolostsleep.Ifthereisacancerrisk,itisasmallone.TheevidenceisstillsocontroversialthatthedraftstirredagreatdealofdebatewithintheBushAdministration,andtheEPAreleaseditoverstrongobjectionsfromthePentagonandtheWhitHouse.Butnownoonecandenythattheissuemustbetakenseriouslyandthatmuchmoreresearchisneeded.Attheheartofthedebateisasimpleandwell-understoodphysicalphenomenon:Whenanelectriccurrentpassesthroughawire,titgeneratesanelectromagneticfieldthatexertsforcesonsurroundingobjects,Formanyyears,scientistsdismissedanysuggestionthatsuchforcesmightbeharmful,primarilybecausetheyaresoextraordinarilyweak.TheELFmagneticfieldgeneratedbyavideoterminalmeasuresonlyafewmilligauss,oraboutone-hundredththestrengthoftheearth’sownmagneticfield,Theelectricfieldssurroundingapowerlinecanbeashighas10kilovoltspermeter,butthecorrespondingfieldinducedinhumancellswillbeonlyabout1millivoltpermeter.Thisisfarlessthantheelectricfieldsthatthecellsthemselvesgenerate.-2-Howcouldsuchminusculeforcesposeahealthdanger?Theconsensususedtobethattheycouldnot,andfordecadesscientistsconcentratedonmorepowerfulkindsofradiation,likeX-rays,thatpacksufficientwalloptoknockelectronsoutofthemoleculesthatmakeupthehumanbody.Such“ionizing”radiationshavebeenclearlylinkedtoincreasedcancerrisksandthereareregulationstocontrolemissions.Butepidemiologicalstudies,whichfindstatisticalassociationsbetweensetsofdata,donotprovecauseandeffect.ThoughthereisabodyoflaboratoryworkshowingthatexposuretoELFfieldscanhavebiologicaleffectsonanimaltissues,amechanismbywhichthoseeffectscouldleadtocancerousgrowthshasneverbeenfound.ThePentagonisforfrompersuaded.Inablistering33-pagecritiqueoftheEPAreport,AirForcescientistschargeitsauthorswithhaving“biasedtheentiredocument”towardprovingalink.“Ourreviewersareconvincedthatthereisnosuggestionthat(electromagneticfields)presentintheenvironmentinduceorpromotecancer,”theAirForceconcludes.“ItisastonishingthattheEPAwouldlenditsimprimaturonthisreport.”ThenPentagon’sconcernisunderstandable.Thereishardlyaunitofthemodernmilitarythatdoesnotdependontheheavyuseofsomekindofelectronicequipment,fromhugeground-basedradartowerstothedefensesystemsbuiltintoeverywarshipandplane.1.ThemainideaofthispassageisA.studiesonthecauseofcancerB.controversialview-pointsinthecauseofcancerC.therelationshipbetweenelectricityandcancer.D.differentideasabouttheeffectofelectricityoncaner.2.Theview-pointoftheEPAisA.thereiscasuallinkbetweenelectricityandcancer.B.electricityreallyaffectscancer.C.controversial.D.lowfrequencyelectromagneticfieldisapossiblecauseofcancer3.WhydidthePentagonandWhitHouseobjecttothereleaseofthereport?BecauseA.itmaystiragreatdealofdebateamongtheBushAdministration.-3-B.everyunitofthemodernmilitaryhasdependedontheheavyuseofsomekindofelectronicequipment.C.thePentagon’sconcernwasunderstandable.D.theyhaddifferentarguments.4.ItcanbeinferredfromphysicalphenomenonA.theforceoftheelectromagneticfieldistooweaktobeharmful.B.theforceoftheelectromagneticfieldisweakerthantheelectricfieldthatthecellsgenerate.C.electromagneticfieldmayaffecthealth.D.onlymorepowerfulradiationcanknockelectronoutofhumanbody.5.Whatdoyouthinkordinarycitizensmaydoafterreadingthedifferentarguments?A.Theyareindifferent.B.Theyareworriedverymuch.C.Themayexerciseprudentavoidance.C.Theyareshocked.Vocabulary1.preposterous反常的，十分荒谬的，乖戾的2.leukemia白血病3.malignancy恶性肿瘤4.legitimate合法的，合理的5.paranoia偏执狂，妄想狂。这里指：无根据的担心。6.lymphoma淋巴瘤7.carcinogen致癌物8.minuscule很小的，很不重要9.consensus舆论10.wallop乱窜，猛冲，冲击力11.epidemiological流行病学的12.blistering罗嗦的，胡扯的13.critique评论，批评14.imprimatur出版许可（官方审查后的），批准-4-难句译注1.Becauseevidenceonthesubjectisinconclusiveandoftencontradictory,ithasbeenhardtodecidewhetherconcernaboutthehealtheffectsofelectricityislegitimate—ortheworstkin