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ID:27486921
大小:1.45 MB
页数:6页
时间:2018-12-04
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1、实用标准文案按住Ctrl键单击鼠标打开配套教学视频名师讲课播放必修5Unit1JOHHSHOWDEFEATS“KINGCHOLERA”JohnSnowwasafamousdoctorinLondon-soexpert,indeed,thatheattendedQueenVictoriaasherpersonalphysician.Buthebecameinspiredwhenhethoughtabouthelpingordinarypeopleexposedtocholera.Thiswasthedeadlydiseaseofitsday.Neither
2、itscausenoritscurewasunderstood.Somanythousandsofterrifiedpeoplediedeverytimetherewasanoutbreak.JohnSnowwantedtofacethechallengeandsolvethisproblem.Heknewthatcholerawouldneverbecontrolleduntilitscausewasfound.Hebecameinterestedintwotheoriesthatpossiblyexplainedhowcholerakilledpeo
3、ple.Thefirstsuggestedthatcholeramultipliedintheair.Acloudofdangerousgasfloatedarounduntilitfounditsvictims.Thesecondsuggestedthatpeopleabsorbedthisdiseaseintotheirbodieswiththeirmeals.Fromthestomachthediseasequicklyattackedthebodyandsoontheaffectedpersondied. JohnSnowsuspectedth
4、atthesecondtheorywascorrectbutheneededevidence.SowhenanotheroutbreakhitLondonin1854,hewasreadytobeginhisenquiry.Asthediseasespreadquicklythroughpoorneighbourhoods,hebegantogatherinformation.Intwoparticularstreets,thecholeraoutbreakwassoseverethatmorethan500peoplediedintendays.Hew
5、asdeterminedtofindoutwhy. Firsthemarkedonamaptheexactplaceswhereallthedeadpeoplehadlived.Thisgavehimavaluableclueaboutthecauseofthedisease.ManyofthedeathswerenearthewaterpumpinBroadStreet(especiallynumbers16,37,38and40).Healsonoticedthatsomehouses(suchas20and21BroadStreetand8and
6、9CambridgeStreet)hadhadnodeaths.Hehadnotforeseenthis,sohemadefurtherinvestigations.Hediscoveredthatthesepeopleworkedinthepubat7CambridgeStreet.Theyhadbeengivenfreebeerandsohadnotdrunkthewaterfromthepump.Itseemedthatthewaterwastoblame. Next,JohnSnowlookedintothesourceofthewaterfo
7、rthesetwostreets.HefoundthatitcamefromtheriverpollutedbythedirtywaterfromLondon.HeimmediatelytoldtheastonishedpeopleinBroadStreettoremovethehandlefromthepumpsothatitcouldnotbeused.Soonafterwardsthediseasesloweddown.Hehadshownthatcholerawasspreadbygermsandnotinacloudofgas. Inanot
8、herpartofLondon,hefoundsupportingevidenc
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