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1、2021届新高考英语一轮复习阅读理解专项训练（3）健康环保类1.FromtalkingrobotsandvideophonestoroversonMars,technologyhasbecomesoadvancedthatthepreviouslyimpossibleseemstooccuronadailybasis.Andyet–westillhavenocureforthecommoncold.Whycan’twestopthecommoncold?AccordingtoPeterBarlow,ascientistatEdinburghNapie
2、rUniversityintheUK,themainchallengeliesinthemanydifferenttypesofcoldvirusesthatareproducedbytherhinoviruses(鼻病毒).Thereareatleast160types.Theymutate(突变)soeasilythattheyquicklybecomeresistanttodrugs,orlearntohidefromourimmunesystems.Inotherwords,asinglecureisn’tlikelytoworkonever
3、ytypeofcold.However,researchersfromStanfordUniversityandtheUniversityofCalifornia,SanFrancisco,havefoundapossibleanswer.Theydiscoveredaproteinthatthevirusesneed.Withoutit,theycan’tspreadinsideyourbody.Toidentifythegenewhichproducesthespecificproteinneededbytheviruses,researcher
4、susedagene-editingtechniquetotestallgenesinthehumangenome(基因组)onebyoneforthousandsofcells.Thesemodified(改变的)cellswerethenexposedtoarangeofenteroviruses(肠病毒),includingtherhinoviruseswhichcausethecommoncold.Alltheviruseswereunabletoreplicate(复制)insidecellswithoutagenethatproduces
5、aspecificprotein,calledmethyltransferaseSETD3.Then,theytestedgeneticallymodifiedmice,whichwerecompletelyunabletoproducetheprotein.Themicewereabletolivehealthy,normalliveswithouttheprotein.“Lackingthatgeneprotectedthemicecompletelyfromviralinfection.”associateprofessorJanCarette
6、,fromStanford,toldtheBBC.“Thesemicewouldalwaysdie,buttheysurvivedandwesawaverystrongreductioninviralreplicationandverystrongprotection.”Carettesaidtheplanistofindadrugwhichcantemporarilysuppress(抑制)theprotein,insteadofproducinggeneticallymodifiedhumans.“Wehaveidentifiedafantast
7、ictargetthatallenterovirusesandrhinovirusesrequireanddependon.Takethatawayandthevirusreallyhasnochance.”saidCarette.“Thisisareallygoodfirststep–thesecondstepistohaveachemicalthatmimics(模拟)thisgeneticdeletion.”headded.1.WhatdoesPeterBarlowthinkisthemainproblemforpreventionofthec
8、ommoncold?A.Theslowmutationofsomegenes.B.Thefastspeeda
