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雅思(閱讀)模擬試卷2(共9套)(共360題)雅思(閱讀)模擬試卷第1套一、綜合題(本題共40題,每題1.0分,共40分。)READINGPASSAGE1Youshouldspendabout20minutesonQuestions1-13,whicharebasedonReadingPassage1below.SECRETOFTHALLAND’SSUCCESS?AIt'saquestionofficialshereinAsiaarebeingposedmoreandmore:Whyareyoureconomiessovibrant?Answersincludeyoungandswellingpopulations,decreaseddebt,growingcities,emergingmiddle-classconsumersectors,evolvingmarketsand,ofcourse,China'srise.Addthistothatlist:WomenandtheirincreasingroleinAsia'seconomies.Theideaisthatthemoreopportunitieswomenhave,themorevibranteconomiesareand,consequently,thelessneedthereistoamassahugepublicdebttoboostgrowth.It'sanideabolsteredbyanewsurveybyMasterCardInternationalInc.,whichcomparesthesocio-economiclevelofwomenwithmeninAsia-Pacificnations.Thegaugeusesfourkeyindicators:participationintheLabourforce,collegeeducation,managerialpositionsandabove-medianincome.BWhichAsiannationisdoingbestwhenitcomestowomen'sadvancement?Thailand.Itscored92.3ofapossible100,andaccordingtoMasterCard'sindex,100equalsgenderequality.Thesurveywasbasedoninterviewswith300to350womeninthirteennationsandnationalstatistics.MaLaysiacameinsecondwithascoreof86.2,whileChinacameinthirdwith68.4.TheaveragescoreinAsiawas67.7.AtthebottomofthelistisSouthKorea(45.5),followedbyIndonesia(52.5)andJapan(54.5).Perhapsit'sabizarrecoincidence,yetMasterCard'sfindingsfitquiteneatlywithtwoimportantissuesinAsia:economicleadershipanddebt.Thailand,MalaysiaandChinaarethreeeconomieswidelyseenasthefutureofAsia.Thailand'seconomicboominrecentyearshaspromptedmanyLeadersintheregiontolookatitsgrowthstrategy.Malaysia,whichhasafemalecentralbankgovernor,isoneofAsia'srisingeconomicpowers.China,ofcourse,istheworld'shottesteconomy,andonethat'sshakinguptradepatternsandbusinessdecisionseverywhere.CSomethingallthreeeconomieshaveincommonisanabove-averageleveloffemaleparticipation.Whatthethreeworstrankedeconomiesshareareseverelong-termeconomicchallengesofhighlevelsofdebtandafemaleworkforcethat'sbeingneglected.Researchineconomichistoryisveryconclusiveontheroleofwomenineconomicgrowthanddevelopment,saysYuwaHedrick-Wong,aneconomicadvisertoMasterCard.Themoreextensivewomen'sparticipationatallareasofeconomicactivities,thehighertheprobabilityforstrongereconomicgrowth.That,Hedrick-Wongsays,meanssocietiesandeconomiesthatconsistentlyfailtofullyincorporatewomen'sabilityandtalentinbusinessesandtheworkplacewillsuffertheconsequences.TakeKorea,whichhasbeenwalkinginplaceeconomicallyinrecentyears.Immediatelyfollowingthe1997-1998Asianfinancialcrisis,Koreabecamearegionalrotemodelasgrowthboomedandunemploymentfelt.Yetamassiveincreaseinhouseholddebtleftconsumersoverexposedandgrowthslowed.DMaybeit'sajustcoincidencethatKoreaalsoranksLowonmeasuresofgenderequalitypublishedbytheUnitedNations.Asof2003,forexample,itrankedbelowHonduras,Paraguay,MauritiusandUkraineintermsofwomen'seconomicandpoliticalempowerment.UtilizingmoreofitsfemaleworkforcewoulddeepenKorea'slabourpoolandincreasepotentialgrowthratesintheeconomy.ThesamegoesforJapan.ThereluctanceofAsia'sbiggesteconomytoincreasefemaleparticipationandletmorewomenintotheexecutivesuiteexacerbatesitsbiggestlong-termchallenge:adecliningbirthrate.In2003,thenumberofchildrenperJapanesewomanfelltoarecordlowof1.79versusabout2intheearly1970s.Preliminarygovernmentstatisticssuggesttheratedeclinedfurtherin7004.Thetrendisnothingshortofacrisisforahighlyindebtednationof126millionthathasyettofigureouthowtofundthenationalpensionsystemdowntheroad.YetJapanhasbeenslowtorealizethatformanywomen,thedecisiontodelaychildbirthisaformofrebellionagainstsocietalexpectationstohavechildrenandbecomehousewives.EItmaybe2005,yethavingchildrenisacareer-endingdecisionformillionsofbright,ambitiousandwell-educatedJapanese.Untilcorrected,Japan'sbirthratewilldropandeconomicgrowthwilllag.UNSecretary-GeneralKofiAnnanwasabsolutelyrightearlierthismonthwhenhesaidnootherpolicyisaslikelytoraiseeconomicproductivitythantheempowermentofwomen.HereinThailand,thegovernmentisgettingsomedecentmarksinthisregardandtheeconomy's6-percent-plusgrowthratemaybeadirectresult.Thailandstillhasalongwaytogo.YettheBankofThailand'sdeputygovernor,TarisaWatanagase,isawoman,asaresevenofnineassistantgovernors.Thenthere'sJadaWattanasiritham,whorunsSiamCommercialBankPlc,Thailand'sfourth-biggestLender.HowmanyfemalechiefexecutivescanyounameinJapanorKorea?LookedatbroadlyinAsia,MasterCard'ssurveyisontosomething.It'sthatgivingwomenmoreopportunitiestocontributetoaneconomyisn'tjustaboutfairness,butdollarsandsense,too.1、Questions1-4Thetexthas5paragraphs(A-E).Whichparagraphcontainseachofthefollowingpiecesofinformation?標準答案:E知識點解析:暫無解析2、*標準答案:B知識點解析:暫無解析3、*標準答案:D知識點解析:暫無解析4、*標準答案:A知識點解析:暫無解析5、Questions5-8CompletethefollowingsentencesusingNOMORETHANTHREEWORDSfromthetextforeachanswer.標準答案:middle-class知識點解析:暫無解析6、*標準答案:nationalstatistics知識點解析:暫無解析7、*標準答案:householddebt知識點解析:暫無解析8、*標準答案:nationalpensionsystem知識點解析:暫無解析9、Questions9-13Dothefollowingstatementsagreewiththeinformationgiveninthetext?TRUE——iftheinformationinthetextagreeswiththestatementFALSE——iftheinformationinthetextcontradictsthestatementNOTGIVEN——ifthereisnoinformationonthisA、真B、假C、NOTGIVEN標準答案:A知識點解析:暫無解析10、*A、真B、假C、NOTGIVEN標準答案:B知識點解析:暫無解析11、*A、真B、假C、NOTGIVEN標準答案:C知識點解析:暫無解析12、*A、真B、假C、NOTGIVEN標準答案:A知識點解析:暫無解析13、*A、真B、假C、NOTGIVEN標準答案:C知識點解析:暫無解析READINGPASSAGE2Youshouldspendabout20minutesonQuestions14-26,whicharebasedonReadingPassage2belowPatientsAreaVirtueADespiteconferencejeers,jobcutsandafinancialcrisis,healthsecretaryPatriciaHewittmayfindareasontosmilethisweek,astheNHS(BritishNationalHealthService)wasnamedoneofthetopplacestoworkbystudents,Amongengineering,scienceandITstudents,thehealthservicewasrankedsecondinthisyear'sUniversumUKgraduatesurveyofidealemployers,aleapof54placesfromlastyear.Theannualsurvey,conductedintheUKsince1997,canvassedtheopinionsofmorethan7700finalandpenultimate-yearstudentsstudyingfordegreesinbusiness,engineering,science,ITandthehumanities,at39universities,betweenJanuaryandMarchthisyear.BEachstudentwaspresentedwithalistof130employers,nominatedbystudentsthroughaseparateprocess,fromwhichtheyselectedthefivetheyconsideredtobeidealemployers.TheUniversumlistisbasedonthefrequencyofanorganisationbeingselectedasanidealemployer,followingaweightingprocess.Thisyear,governmentdepartmentsandpublicsectororganisationsdominatedthetopspots,withtheBBCrankedfirstamonghumanities,engineering,scienceandITstudents,retainingitsplacefromlastyear,andcomingthirdforthosestudyingbusiness.Amonghumanitiesstudents,theBBCwasfollowedcloselybytheForeignandCommonwealthOfficeandtheCivilServicefaststream.TheCabinetOfficeandtheMinistryofDefencewerenotfarbehind,rankedfifthandsixthrespectively,AswellastheNHS,engineering,scienceandITstudentsfavouredtheEnvironmentAgency,whichleapt83places,from86in2005tonumberthreethisyear.Meanwhile,businessstudentsvotedaccountancygiantsPricewaterhouseCoopers(PwC)astheirfavouredemployer,followedbyHSEC.CAtaLondonawardsceremonysponsoredbytheGuardian,FolukeAjayi,headofNHScareersatNHSemployers,saiditssuccessthisyearreflectedtherealityofthehealthservice,whichisthethirdlargestemployerintheworldandthelargestinEurope,"Weemploypeopleinotherclinicalareas,suchashealthcare.WeemployITmanagers,engineers,architects"shesaid,addingthatthehealthserviceisnolongerseenasa"secondchoice"career."Peoplerecognisethattheycangivesomethingbacktothecommunity,butstilldevelopaworthwhilecareer."DSarahChurchman,directorofstudentrecruitmentanddiversityatPwC,saidhercompany'ssuccessisdowntoagoodcampuspresence,itscommitmenttoinvestinitsemployeesand,withofficesaroundtheworld,thechancetotravel,somethingwhichjustunderhalfofthestudentspolledsaidwasanimportantfactorwhenitcametolookingforwork.Oneofthebigfouraccountancyfirms,PwCisnotintogimmicks,anditdoesn'tofferfreebiesbut,saidChurchman,itdoesoffer"asolidfoundation"foranyonewantingacareerinbusiness."Wesellourpeopleskillssoweareinterestedinbuildingskills,we'renotsellingsomething,weinvestinourpeople."sheadded.EFurtherdowntherankings,butstillwithreasontocelebrate,wasJohnLewis,whichmatchedbumpersalesthisyearwithaleapfrom111thplacein2005to26thamongthisyear'shumanitiesstudents.Skyfounditselfin12thplace,upfrom104thlastyearandtheEnvironmentAgencyalsoprovedpopularamongthisstudentgroup,risingfrom138thin2005to7ththisyear.Amongthebusinessfraternity,Shellsawareversaloffortunes,risingto30thplaceafterlastyear's76thposition.Therewereafewdramaticdropsintherankings.TheBankofEnglandfellfrom14thin2005to27ththisyearamonghumanitiesstudents,althoughitretaineditsmid-tablepositionamongthosestudyingbusiness.BritishAirwaysalsosawaslightdip,asdidMcKinsey&Co,whichdroppedfrom11thto22ndamongbusinessundergraduates.FPerhapsmoresurprisingly,thisyearwasthefirstappearanceintherankingsofTeachFirst.asmallcharitylaunchedthreeyearsagothataimstocreatethe"leadersofthefuture"byencouragingtopgraduateswhowouldnotnormallyconsideracareerinteachingtocommittoworkin"challenging"secondaryschoolsforatleasttwoyears.Theorganisationcamestraightinatnumbereightamonghumanitiesstudentsandwasvoted22ndbythosestudyingengineering,scienceandIT,JamesDarley,directorofgraduaterecruitmentatTeachFirst,saidhewas"bowledover"bythenews."Wewerenotexpectingthis.We'rearegisteredcharity,onlyabletophysicallygoto15universities."GThescheme,basedononerunintheUS,hasthebackingofmorethan80businesses,includingDeloitteandHSBC.Duringtheirtwoyears,candidatesundertakeleadershiptrainingandemergefromtheprogrammewitharangeofskillsandexperiences."Wehopeinthelongtermtheywillbeourambassadors,aswecallthem,inpolitics,industry,charitieswhowillhavedoneitandcontinuetosupporttheeducationallydisadvantaged,"addsDarley.Thisyear,260graduatesareexpectedtotakeuptheTeachFirstchallengeinschoolsinLondonandManchester.Moreareexpectedoverthecomingyears,astheschemeexpandstoBirminghamandthreeothercitiesby2008.Ofthefirstsetofrecruitstocompletetheprogramme,halfhavegoneontoworkfor"someamazingcompanies"whiletheotherhalfhavechosentostayonintheirschoolsforafurtheryear--20%inleadershiproles.HWhilemorethanhalfofstudentswereconcernedaboutachievingagoodwork/lifebalance,athirdsaidtheywantedajobthatwouldchallengethem.Althoughmalestudentstendedtofocusmoreonthepracticalaspectsofwork,suchas"buildingasoundfinancialbase",women,particularlythosestudyingforhumanitiesdegrees,hadamoreidealisticoutlook,sayingmakingacontributiontosocietywasakeycareergoal.Almosthalfofallstudentssaidthatpaidovertimewasakeypartofanycompanycompensationpackage.However,businessstudentssaidthatthemostimportantcompensation,apartfromsalary,wasperformance-relatedbonuses,whileimportantconsiderationsforhumanitiesstudentswereretirementplans.Workingoverseasalsoscoredhighlyamongthosesurveyedthisyear.with45%ofbusinessstudents,and44%ofhumanitiesstudents,listingitasapriority.Ethicalconsiderationsandcorporatesocialresponsibilitieswerealsomentioned,withalargepercentageofhumanitiesandengineering,scienceandITstudentssayingitwasakeyconsiderationwhenitcametochoosinganemployer.14、Questions14-17Thetexthas8paragraphs(A-H).Whichparagraphdoeseachofthefollowingheadingsbestfit?標準答案:B知識點解析:暫無解析15、*標準答案:H知識點解析:暫無解析16、*標準答案:C知識點解析:暫無解析17、*標準答案:A知識點解析:暫無解析18、Questions18-22Accordingtothetext,FLVEofthefollowingstatementsaretrue.Writethecorrespondinglettersinanswerboxes18to22inanyorder.[A]Inthesurvey,studentscouldonlyrateemployersonagivenlist.[B]TheEnvironmentAgencyrosethemostplacesinthisyear’ssurvey.[C]TheNHSoffersavarietyofcareersoutsidehealthcare.[D]BritishAirwaysfellinpopularityamongstbusinessstudents.[E]JamesDarleywassurprisedbyhisorganisation’sperformanceinthesurvey.[F]Most’TeachFirst’teacherscontinueinateachingcareeraftertwoyears.[G]Moststudentswanttoachieveagoodwork/lifebalance.[H]Mostbusinessstudentswereconcernedaboutworkingforanethicalcompany.標準答案:A知識點解析:暫無解析19、*標準答案:C知識點解析:暫無解析20、*標準答案:D知識點解析:暫無解析21、*標準答案:E知識點解析:暫無解析22、*標準答案:G知識點解析:暫無解析23、Questions23-26Accordingtotheinformationgiveninthetext,choosethecorrectansweroranswersfromthechoicesgiven.A、fromallBritishuniversities.B、studyingavarietyofsubjects.C、whowereintheirlastyearofstudiesonly.標準答案:B知識點解析:暫無解析24、*A、wasfirstchoiceinmostcategories.B、wasunpopularwithbusinessstudents.C、employsmoregraduatesthanmostotherorganizationsandcompanies.標準答案:A知識點解析:暫無解析25、*A、oftengoestouniversitiestomeetstudents.B、providesmanyscholarshipsforstudents.C、offersmanyopportunitiestotravel.標準答案:AC知識點解析:暫無解析26、*A、focusesonthebestuniversitystudents.B、focusesongettingteachersforbestschools.C、isbasedonasimilarorganisationinAmerica.標準答案:AC知識點解析:暫無解析READINGPASSAGE3Youshouldspendabout20minutesonQuestions27-40,whicharebasedonReadingPassage3below.RiseoftheRobotsIfyou'reintotechnology,you'relivinginwonderfultimes.Thingsaredevelopinginleapsandbounds,especiallygadgets.Let'slookatthetechnologythat'ssettobreakthrough.CELESTRONSICYSCOUTBackyardstar-gazinggoesseriouslyhi-techwiththeCelestronSkyScout,whichwasjudgedtobetheBestofInnovationsattheNewYorkConsumerElectronicsShowpressprevieweventinNovember.It'snordifficulttoseewhy.TheSkyScoutisahand-heldviewingdevicethat'scapableoffindingandidentifyingmorethan6000celestialobjectsvisibletothenakedeye,thustransformingthenightskyintoyourownpersonalplanetarium.UsingGPStechnologyandasubstantialcelestialdatabase,thecamcorder-sizedSkyScoutenablesstargazerstopointthedeviceatanyvisibleobjectinthesky,pressabuttonandthenlistentoacommentary.Forthetrulycelestiallychallenged,ifyouwanttoviewastarorplanetbuthaven'tacluewhichbitoftheheavenstolookin,don'tdespair,theSkyScout's“locate”featurewillguideyoutoitusingilluminatedarrowsintheviewfinder.NOKIAN91Thisamazingmobilejukeboxisdueoutearlyin2006.Nokia'sN91lookssettobeinaclassofitsownasamultimediamobilephone,Itwillplaymusic,takephotos,surfthewebanddownloadvideos,storecontactdetailsandgenerallyorganiseyourlife.Therobustlittlephone,resplendentinitsstainlesssteelcase,isthefirstNokiatobeequippedwithaharddrive(4Gb),whichmeansthatitcanstoreupto3000songs.TheN91,whichhasahi-fiqualityheadsetandremotecontrol,supportsawiderangeofdigitalmusicformats,includingMP3,Real,WAVandWMA,Ituseswirelesstechnologytoallowuserstofindandbuymusicfromtheoperator'smusic-store,YoucanalsodraganddropmusicfromyourPCtotheN91andmanageandshareplay-lists.Ifyoucanfindthetime.youcangetontheblower,too.SEIKOSPECTRUME-PAPBRWATCHTheSeikoSpectrumisnoordinarywristwatch.Atfirstglance,it'sanattractiveandfuturisticbracelet-stylewatch.Lookcloser,however,andyou'llnoticethatitsdisplayisunlikeanyyou'veseenbefore.RatherthantheusualLCDscreen,thedisplayismadeof"e-paper"--fromtheelectronicpaperpioneersEInkCorp--andshowsaconstantlychangingmosaicpatternalongwiththetime.Becausee-paperissoflexibleandthin,itallowsthedisplaytocurveroundthewristalongwiththewatchband--somethingconventionalliquid-crystaldisplayscannotdo,astheyhavetobeflat.Seikosaysthee-paperdisplaynotonlyproducesfarbettercontrastthananLCDscreen,butrequiresnopowertoretainanimage,sothebatterieslastlonger.Seikoisreleasingonly500ofthewatchesnextmonth,pricedatabout£1,250--soyou'dbetterlosenotime.HIGH-DEFINITIONTVHDTV,alreadyavailableintheUnitedStates,JapanandAustralia,willhittheUKin2006.WhenyouwatchaprogrammefilmedintheHDformat,you'llseeamuchsharper,clearerandmorevibrantimage.Thisisduepartlytothewayaprogrammeisfilmed,butalsotothehigh-definitionTVsetitself,whichuseseither720or1080visiblerowsofpixels(dependingonwhichformattheindividualHDTVuses)todisplayimages,comparedtothe576rowsofpixelsusedincurrentsets.ELECTROLUXTRILOBITB2.0ROBOTVACUUMCLEANERNexttimeyou'reexpectingvisitors,don'tbothertovacuumfirst--waituntiltheyarrive,andthenentertainthemwiththislittlegadget.TheElectroluxTrilobite2.0isaroboticvacuumcleanerthatnavigatesitswayaroundyourfloorsusingultrasound,justlikeabat.Itpingsoutultrasoundvibrationsatsurfacestocreateamapoftheroom,whichitremembersforfuturecleaningassignments.TheTrilobitehasnoproblemavoidingcollisionwiththingsplacedonthefloor.Specialmagneticstripsareplacedindoorways,nearstairsandotheropenings.Theseactasawall.keepingtheTrilobiteintheroom.Youcanalsoprogrammeittoglideroundwhenyou'reatworkorafteryou'vegonetobed.WhenElectroluxintroducedtheoriginalTrilobitein2001.itwasvotedamongthe100most-innovativedesigns(thoughwhetherthejudgeswerededicatedcouch-potatoes,andthusbiased,wewerenotabletodiscover).Thenamecomesfromthehard-shelledseacreaturefromthePaleozoicera(between250millionand560millionyearsago)thatroamedtheoceanfloorfeedingonparticlesandsmallanimals.HONDAASIMOROBOTNeedanextrapairofhandsaroundtheoffice?Looknofurther;thismonth,theHondaMotorCompanyshowcaseditssecond-generationhumanoidrobot.Asimo.Themachinehascomealongwaysinceitsfirstincarnationfiveyearsago.The1.3metre-talldroidisnowcapableofperformingavarietyofofficetasks,includingreceptionduties,servingdrinksandactingasaninformationguide,aswellasmakingdeliveries.Usingmultiplesensors,Asimohastheabilitytorecognisethesurroundingenvironmentandinteractwithpeopleusingintegratedcircuittags.Itcanwalkandrunatafairpace,andpushacart.HondaplanstostartusingAsimo'sreceptionistfunctionsatitsWakoBuildinginJapanearlyin2006,andit'shopeditwillbecomeavailableforleasingafterwards.Itcouldsoonbepushingacartatanofficenearyou.27、Questions27-30Foreachquestion,onlyONEofthechoicesiscorrect.Writethecorrespondingletterintheappropriateboxonyouranswersheet.A、tellyouinformationaboutthestars.B、tellyouwhereintheworldyouare.C、findobjectsintheskythatarenotnormallyvisible.標準答案:A知識點解析:暫無解析28、*A、cannotbebent.B、canbeusedforsurfingtheinternet.C、isbeingproducedasalimitededition.標準答案:C知識點解析:暫無解析29、*A、askspermissionbeforemovingfromroomtoroom.B、useslaserstohelpitavoidobjects.C、isprogrammable.標準答案:C知識點解析:暫無解析30、*A、hastwopairsofhands.B、useslaserstohelpitrecognizeitssurroundings.C、canrun.標準答案:C知識點解析:暫無解析31、Questions31-35CompletethefollowingsentencesusingNOMORETHANTHREEWORDSfromthetext.標準答案:arrows/illuminatedarrows知識點解析:暫無解析32、*標準答案:e-paperdisplay知識點解析:暫無解析33、*標準答案:rowsofpixels知識點解析:暫無解析34、*標準答案:entertain知識點解析:暫無解析35、*標準答案:fiveyearsago知識點解析:暫無解析36、Questions36-40Dothefollowingstatementsagreewiththeinformationgiveninthetext?TRUE——iftheinformationinthetextagreeswiththestatementFALSE——iftheinformationinthetextcontradictsthestatementNOTGIVEN——ifthereisnoinformationonthisA、真B、假C、NOTGIVEN標準答案:A知識點解析:暫無解析37、*A、真B、假C、NOTGIVEN標準答案:C知識點解析:暫無解析38、*A、真B、假C、NOTGIVEN標準答案:A知識點解析:暫無解析39、*A、真B、假C、NOTGIVEN標準答案:C知識點解析:暫無解析40、*A、真B、假C、NOTGIVEN標準答案:C知識點解析:暫無解析雅思(閱讀)模擬試卷第2套一、綜合題(本題共40題,每題1.0分,共40分。)Microbubbles:Anewtechniquetotreatdiseaseinvolvesthecarefulinjectionoftiny,drug-coatedbubblesinthebloodstream.AThiloHoelscher,aneurologistattheUniversityofCalifomia,SanDiego,isamanwithaplan.Hisplanistodealwithstrokesbyblowingbubblesatthem.Thebubblesinquestionwouldbesmallenoughtoinjectintobloodvesselsleadingtotheaffectedpartofthebrain.Whentheygottothebloodclotthatcausedthestroke,theywouldbejiggledintoactionbytheapplicationofultrasound.Theresultwouldbemyriadsoftinyjackhammerschippingawayattheclotbeforeithadachancetocausetoomuchpermanentdamage.BWhatmakesthisapproachparticularlyinterestingisthatDrHoelscherwantstostarttreatingstrokepatientsassoonastheyareheavedintoanambulance,ratherthanwaitinguntiltheyarriveintheemergencyroom.HeplanstostartafeasibilitystudybeforetheendoftheyearinwhichsomeofSanDiego'sambulanceswillbeequippedwithportableultrasonictransducers.AndreiAlexandrov,apioneerintherapeutic-ultrasoundresearchwhonowdirectsthestrokecentreattheUniversityofAlabama,ispursuingasimilarapproach.Heisdesigninganeasy-to-useultrasoundhelmetthatanemergency-roomnursecanattachbeforeadministeringavialofmicrobubbles.Bothschemesareexamplesofanewideainmedicine,Whichistousetinybubblesofgasnotmerelytohighlightorgansduringultrasonicscanning,ashasbeendoneforseveralyears,butalsoasaformoftreatment.Withclinicaltrialsnowgettingunderway,expertsthinkitwilltakearoundfiveyearsforthesenewtherapiestoreachpatients.CMicrobubblesarenotjustanyoldbubbles.Theycontainachemicallystablegas,suchasperfluoropropane,insteadofair.Thisgasisencapsulatedinafattyshellratherlikeaverysmallballoon.Eventhelargestmicrobubblesbeingtestedformedicaluseareonlyfivemicronsacross,lessthanthediameterofaredbloodcell.Moreadvancedbubblesareonlyafewhundrednanometresacrossandcanmoveeasilythroughtheliningofabloodvessel.Theymayalso,crucially,beabletocrosstheblood-brainbarrier,atightlysealedlayerofcellsthatprotectsthebrainfromdangerouschemicalsincludingmanydrugs.Ifyouputsuchadruginthesurfacelayerofamicrobubble,youmightbeabletosmuggleitintothebrain.DHavinggotintothebrain(oranywhereelse),awell-designedmicrobubbleshouldalsobeablefindaparticulartarget.Thatisbecausethefattylayercanincludemoleculessuchasantibodies,whichlinkupwithproteinsfoundonthesurfacesofonlyonetypeofcell.Abubblewithsuchanantibodyinitwouldthusstickonlytothattypeofcell.ThissortofapproachisbeingtestedbyMarkBordenandPaulDayton,whoworkatanotheroftheUniversityofCalifornia'scampuses,inDavis.Theyhavedemonstratedinratsthatbubbleswithanappropriateouterlayercanbeequippedwithmoleculesthatstickspecificallytodiseasedcells.Thesemoleculesareinitiallyhiddenunderapolymerlayertopreventtheimmunesystemfromdestroyingthebubbles.Whenthebubblearrivesatitstarget,however,itisblastedwithultrasoundinawaythatexposesthemoleculeandmakesthebubblestick.EThetworesearcherscanalsousesoundwavestosteerbubblestowardsatarget,asifthosebubblesweresurfingawaveinthesea.Moreover,theycanslowthebubblesdownwhentheyarrivewheretheyarewanted.Oncethebubbleshavestuckgoodandfasttotheirtargets,turninguptheultrasoundstillfurtherwillburstthem,sothattheyreleasetheirpayloadspreciselywheretheycandomostgood.Theresultissmaller,better-aimeddosesofdrugs,whichshouldmeanfewerside-effects.Inprinciple,suchpaytoadscouldbesmall-moleculedrugssuchasthoseusedforcancerchemotherapy.Theycouldbetherapeuticproteinssuchasantibodiesandcertainhormones.Theycouldberadioactiveisotopesdesignedforhighlylocalradiotherapy.TheycouldevenbepiecesofDNAintendedasgenetherapy.FSuchwork,ofcourse,isnotconfinedtotheacademy.ImaRxTherapeuticsofTucson,Arizona,hasjustbegunatrialofitsownbubble-basedstroketherapy,whichitisbrandingasSonoLysis.Thebubblesarebeingtestedinconjunctionwithanestablishedclot-bustercalledtPA.Meanwhile,twootherAmericanfirms,NanotropeandTargeson,areworkingonwaysofmakingcustomisedbubblestoorder,thelatterbyforcinganemulsionofwaterandoilcombinedwithwhatevertherapeuticagentisdesiredthroughanarrowplasticnozzleathighspeed.GBubbletherapyisnotyetreliable.Safedosesofsoundwaves,thebestsizeforthebubblesandtheamountofdrugeachshouldcarryhavealltobeworkedout.Atleastonetrial,runbyMichaelDaffertshoferoftheUniversityofMannheim,inGermany,hadtobestoppedbecausetheresearchersdiscoveredthattheultrasoundwascausingbrainhaemorrhages.Yetifsafecombinationsofbubblesandultrasoundcanbefound,blowingbubblesatdiseasescouldbeacleverwaytotackleproblemswhereth

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