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20xx大学英语四级考试模拟试卷及答案(6):英语四

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PartⅠWriting(30minutes)

Directions:Forthispart,youareallowed30minutestowritea

uldwriteatleast120

wordsfollowingtheoutlinegivenbelowinChine:

DormitoryLife

1.大学宿舍的集体生活是全新的体验。

2.宿舍生活与在家生活的不同之处。

3.宿舍生活利与弊。

PartIIReadingComprehension(SkimmingandScanning)

Directions:Inthispart,youwillhave15minutestogooverthe

passagequicklyandanswerthequestionsonAnswersheet1.

TestingTimes

Rearchersareworkingonwaystoreducetheneedforanimal

experiments,butnewlawsmayincreathenumberofexperimentsneeded.

Thecurrentsituation

Inanidealworld,peoplewouldnotperformexperimentsonanimals.

Forthepeople,animals,theyarestressful

andoftenpainful.

Thatidealworld,sadly,neednewdrugs

,theEuropean

Commissionisforgingaheadwithproposalsthatwillincreathenumber

ofanimalexperimentscarriedoutintheEuropeanUnion,byrequiring

toxicitytestsoneverychemicalapprovedforuwithintheunion”s

bordersinthepast25years.

2

Already,thecommissionhasidentified140,000chemicalsthathave

s30,000ofthetobeexaminedrightaway,

andplanstospendbetween~4billion—8billion($5billion—10billion)

berofanimalsudfortoxicitytestinginEuropewill

thus,expertsreckon,quintuple(翻五倍)fromjustoverlmayeartoabout

5m,unlesstheyaresavedbysomedramaticadvancesinnon-animaltesting

oment,roughly10%ofEuropeananimaltestsarefor

generaltoxicity,35%forbasicrearch,45%fordrugsandvaccines,and

theremaining10%avarietyofussuchasdiagnosingdias.

Animalexperimentationwillthereforebearoundforsometimeyet.

Butthearchforsubstitutescontinues,andlastweekendtheMiddle

EuropeanSocietyforAlternativeMethodstoAnimalTestingmetinLinz,

Austria,toreviewprogress.

Agoodplacetostartfindingalternativesfortoxicitytestsisthe

liver--theorganresponsibleforbreakingtoxicchemicalsdownintosafer

ms,onelargeandonesmall,

toldthemeetinghowtheywereusinghumanlivercellsremoved

incidentallyduringsurgerytotestvarioussubstancesforlong-term

toxiceffects.

Onewayoutoftheproblem

PrimeCyte,thesmallfirm,growsitscellsinculturesoverafewweeks

characteristicsofthecellsarecarefullymonitored,tolookforchanges

intheirmicroanatomy.

Pfizer,thebigfirm,alsodositsculturesregularly,butrather

thanstudyingindividualcellsindetail,

numberofcellsinaculturechangesafterasampleisadded,thatsuggests

thechemicalinquestionisbadfortheliver.

Inprinciple,

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practice,drugs(and,inthecaofPrimeCyte,foodsupplements)aretop

tmightchangeifthecommissionhasitsway:tho

140,000screeningslooklikealucrativemarket,althoughnobodyknows

whetherthenewtestswillbereadyforuby20xx,whenthecommission

proposthattestingshouldstart.

Othertissues,too,lix,

asmallfirminGeneva,hasdevelopedanartificialversionofthelining

ingtoHuangSong,oneofEpithelix”srearchers,

thefirm”sculturedcellshavesimilarmicroanatomytothofoundin

naturallunglinings,andrespondinthesamewaytovariouschemical

aysthattheycouldbeudinlong-termtoxicity

testsofairbornechemicalsandcouldalsohelpidentifytreatmentsfor

lungdias.

Theimmunesystemcanbemimickedandtested,Gen,a

companybadinBerlin,isdevelopinganartificialhumanlymphnode(淋

巴结)which,itreckons,couldhavepreventedtheneardisastrous

conquencesofadragtrialheldinBritainthreemonthsago,inwhich

(despitethedraghavingpasdanimaltests)sixmensufferedmultiple

gthemenweregivenmadetheir

esponwould,thefirm”sscientists

reckon,naveteenidentifiedbytheirlymphnode,whichismadefromcells

Gen”slymphnode

dalternative

Anotherwayofcuttingthenumberofanimalexperimentswouldbeto

changethewaythatvaccinesaretested,accordingtoCoenraadHendrikn

oment,allbatchesof

knargues

wvaccineculturesaremade,

batchof

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vaccineisderivedfromanexistingculture,hesuggeststhatitneedbe

testedonlytomakesureitisidenticaltothebatchfromwhichitis

uldrequirefewertestanimals.

Allthissuggeststhatthoughthereisstillsomewaytogobefore

drugs,vaccinesandothersubstancescanbetestedroutinelyoncells

ratherthanliveanimals,harder

toeishowtheuofanimalsmightbebanishedfromfundamental

ngthebalance

Inbasicscientificrearch,wheretheobjectistounderstandhow,

say,thebrainworksratherthantodevelopadrugtotreatbraindia,

,insome

cas,scientificadvancesaremakinganimaltestsmorevaluable,rather

cmodificationtechniquesmeanthatmiceandratscanbe

remodelledtomakethemexhibitillnessthattheywouldnotnormally

,genesforhumanproteinscanbeaddedtothem,sothat

fersthe

opportunitytounderstandhumandiasbetter,andtoscreentreatments

r,theverycreationofthemutants

(突变异种)countsasananimalexperimentinitsownright,sothenumber

ofexperimentsisincreasingonceagain.

Whatisbadnewsforrodents,though,couldbegoodnewsforprimates.

Apesandmonkeysbelongtothesamegroupofmammalsashumans,andare

extentthatrodentscanbe“humanid”,thenumberofprimate

experimentsmightbereduced.

Somepeople,ofcour,wouldliketoethemeliminatedaltogether,

6ththeBritishUnion

fortheAbolitionofViviction,ananimal-rightsgroup,calledforthe

atapes,thishasalready

5

n,Austria,theNetherlands,NewZealandandSwedenhave

endedexperimentsonchimpanzees,gorillas,bonobosandorang-utans.

Experimentsonmonkeys,though,ecountries

ica,forexample,about1,000

chimpanzeesayearareudinrearch.

pesareman”sclostrelatives,

havingpartedcompanyfromthehumanfamilytreeonlyafewmillionyears

tcanbe(andis)arguedthattheyareindispensablefor

therhand,arecentstudybyAndrew

KnightandhiscolleaguesatAnimalConsultantsInternational,an

animal-advocacygroup,castsdoubtontheclaimthatapesareudonly

antpaperstendtoget

citedasreferencesinsubquentstudies,lookedintothe

numberofcitationsreceivedby749scientificpaperspublishedasa

dreceived

notasinglecitationuptotenyearsaftertheiroriginalpublication.

experimentsareneededfortheadvanceof

medicalscience,nottomentionpeople”s

cientistsaretokeepthesympathyofthepublic,they

needtodobetterthanthat.

sagesummarizesharmfuleffectsofanimalexperiment.

However,asanimalexperimentisindispensableinanumberofareas,it

mightnotbestoppedorreplacedbyotheralternatives.

experimentsareneededinrearchtofindnewdrugsand

vaccines,andtofindwaysofprotectionfromthetoxicityofchemicals.

edictedbyexpertsthatthenumberofanimalsudfor

toxicitytestinginEuropewillquintupleduetoaplantohavealarge

varietyofchemicaltested.

aretryingtofindalternativestoanimaltesting,andthey

6

startedwithliver.

yteandPfizerbegantofindalternativestoanimaltesting

becautheywereadvocatesofanimalprotection.

undthattissuesfromliver,lung,andimmunesystemcan

allbetestedindependentlyofanimals.

ghthereismorethanonealternativetoanimalexperiment,

thereisstillconcernoverhowtoeliminateanimaltestinginfundamental

rearch.

cscientificrearch,theobjectistounderstandhow,say,

thebrainworksratherthantodevelopadrugto______braindia.

,insomecas,scientificadvancesaremakinganimaltests

___________

ly,ananimal-advocacygroupcastsdoubtonthe

scientists”claimthatapesareudonlyfor__________