每日一读2014年高考英语8月考前突破阅读理解能力文化教育大气污染可能会使脑部受损素材

1大气污染可能会使脑部受损Anewresearchdescribeshowthebrainsofmicearedamagedbyexposuretoairpollutioninearlylife.一项新研究表明，老鼠若在幼年期长期接触污染大气，脑部可能会受损。Thebraindamageincludestheenlargementofapartofthebrainthatisseeninhumanswhohaveautismandschizophrenia.ThestudyispublishedinthejournalEnvironmentalHealthPerspectives.Asinautismandschizophrenia（精神分裂症）,thechangesoccurredpredominatelyinmales.Themicealsoperformedpoorlyintestsofshort-termmemory,learningability,andimpulsivity.Thenewfindingsareconsistentwithseveralrecentstudiesthathaveshownalinkbetweenairpollutionandautisminchildren.Mostnotably,a2013studyinJAMAPsychiatryreportedthatchildrenwholivedinareaswithhighlevelsoftraffic-relatedairpollutionduringtheirfirstyearoflifewerethreetimesaslikelytodevelopautism.Ourfindingsaddtothegrowingbodyofevidencethatairpollutionmayplayaroleinautism,aswellasinotherneurodevelopmentaldisorders,saidDeborahCory-Slechta,Ph.D.,professorofenvironmentalmedicineattheUniversityofRochesterandleadauthorofthestudy.Inthreesetsofexperiments,Cory-Slechtaandhercolleaguesexposedmicetolevelsofairpollutiontypicallyfoundinmid-sizedUScitiesduringrushhour.Theexposureswereconductedduringthefirsttwoweeksafterbirth,acriticaltimeinthebrain'sdevelopment.Themicewereexposedtopollutedairforfourhourseachdayfortwofour-dayperiods.Inonegroupofmice,thebrainswereexamined24hoursafterthefinalpollutionexposure.Inallofthosemice,inflammationwasrampantthroughoutthebrain,andthelateralventricles（侧脑室）--chambersoneachsideofthebrainthatcontaincerebrospinalfluid--wereenlargedtwotothreetimestheirnormalsize.Whenwelookedcloselyattheventricles,wecouldseethatthewhitematterthatnormallysurroundsthemhadn'tfullydeveloped,saidCory-Slechta.2Itappearsthatinflammationhaddamagedthosebraincellsandpreventedthatregionofthebrainfromdeveloping,andtheventriclessimplyexpandedtofillthespace.Theproblemswerealsoobservedinasecondgroupofmice40daysafterexposureandinanothergroup270daysafterexposure,indicatingthatthedamagetothebrainwaspermanent.Brainsofmiceinallthreegroupsalsohadelevatedlevelsofglutamate（谷氨酸盐）,aneurotransmitter,whichisalsoseeninhumanswithautismandschizophrenia.