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The United States In 1782 【51】 the United States won its independ...
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NewTechniquePromisesEarlierCancerDetection AnewtechniquecouldrevolutionizetheearlydetectionofcancergivingsufferersagreaterchanceofbeatingthediseaseAmericanscientistssaid.ResearchersattheMassachusettsInstituteofTechnologyhavedevisedanovelmethodof【51】changesinthenucleusofcellsintheearlieststagesofthedisease.Morethan85percentofallcancersoriginateintheepithelium上皮thatlinestheinternalsurfacesoforgans【52】thebody.Althoughthesearetreatable【53】theyarediagnosedinoneofthepreventablestagesearlybodydamagesarealmost【54】todetectsaidscientistFeld.Wepresentanewoptical-probe光学探子techniquebasedonlight-scatteringspectroscopy分光镜检查thatisable【55】detectprecancerousandearlycancerouscellsincell-richepitheliaheaddedinastatement. Thenewtechniquereliesonthefact【56】cellnucleichangeintheearlystagesofcancerandthedifferencesscatterlightinacharacteristicway.Untilnowthechangeswereonlydetectable【57】abiopsy活检wastakenthescientistssaid.Thenewtechnique【58】inthesciencejournalNaturecanbeusedinconjunctionwitharoutinecancerscreeningandsurveillancetechniquewhichusesanendoscope内窥镜—aflexibleopticalprobe【59】withcameraswhichisinsertedintoacavityinthebody—tocheck【60】cancers. Thescientistssaidthey【61】theirnewtechniqueinfourdifferentorgansduringroutineendoscopiccancerscreening.Thetipoftheopticalprobewasbroughtintocontactwiththetissuetobetestedandthescatteringoflightwasrecordedwithouttheneedforanytissuetobe【62】thescientistssaid.Ourresultsshowthatlight-scatteringspectroscopyhasthepotentialtodetectpre-cancerousbodydamagesandpreinvasivecancersthroughoutthebody.Thistechniqueshould【63】improvetheefficiencyofcancerscreeningandsurveillancethescientistssaid.Cancerisoneofthebiggest【64】inindustrializedcountries.【65】tofiguresfromtheWorldHealthOrganization10millionpeoplewerediagnosedwiththediseaseworldwidein1997andsixmilliondied.
TheGrandCanyon StandingontherimoftheGrandCanyon大峡谷gazingacrossthisgiantwoundintheEarth’’ssurfaceavisitormightassumethatthecanyonhadbeencausedbysomeancientconvulsion震动.Infacttheeventsthatproducedthecanyonfarfrombeingsuddenandcatastrophicsimplyadduptotheslowandorderlyprocessoferosion. ManymillionsofyearsagotheColoradoPlateauintheGrandCanyonareacontained1000morefeetofrockthanitdoestodayandwasrelativelylevel.Theadditionalmaterialconsistedofsome14layeredformationsofrock.IntheGrandCanyonregiontheselayerswerelargelywornawayoverthecourseofmillionsofyears. Approximately65millionyearsagotheplateausflatsurfaceintheGrandCanyonareabulgedupwardfrominternalpressuregeologistsrefertothisbulgingactionsupwarding弯曲上升;itwasfollowedbyageneralelevationofthewholeColoradoPlateauaprocessthatisstillgoingon.Astheplateaugraduallyroseshallowriversthatwindedacrossitbegantorunmoreswiftlyandcutmoredefinitecourses.OneoftheseriverslocatedeastoftheupwardwastheancestoroftheColorado.AnotherriversystemcalledtheHualapaiflowingwestoftheupwardextendeditselfeastwardbycuttingbackintotheupwarditeventuallyconnectedwiththeancientColoradoandcaptureditswaters.Thenewriverthenbegantocarveoutthe277-mile-longtrenchthateventuallybecametheGrandCanyon.Geologistsestimatethatthisinitialcuttingactionbegannoearlierthan10millionyearsago. SincethentheCanyonforminghasbeencumulative.Tothecorrosiveforceoftheriveritselfhavebeenaddedotherfactors.Heatandcoldrainandsnowalongwiththevaryingresistanceoftherocksincreasetheopportunitiesforerosions.TheCanyonwallscrumbletheriveracquiresacuttingtool.Tonsofdebrisrainfallrunningoffthehighplateaucreatesfeederstreamsthatcarresidecanyons.Pushingslowlybackwardintotheplateauthesidecanyonsexposenewrocksandthepatternoferosioncontinues. ThewordwoundLine1Para.1indicatesthat______.
AHierarchyofHormones Allofthecellsinaparticularplantstartoutwiththesamecomplementofgenes.Howthencanthesecellsdifferentiateandfromstructuresasdifferentasrootsstemsleavesandfruits?Theansweristhatonlyasmallsubsetofthegenesinaparticularkindofcellareexpressedorturnedonatagiventime.Thisisaccomplishedbyacomplexsystemofchemicalmessengersthatinplantsincludehormonesandotherregulatorymolecules.Fivemajorhormoneshavebeenidentified;auxin生长素abscisicacid脱落酸cytokinin细胞激动素hetylene乙烯andgibberellin赤霉素.Studiesofplantshavenowidentifiedanewclassofregulatorymoleculescalledoligosaccharins. Unliketheoligosaccharinsthefivewell-knownplanthormonesarepleiotropic多向性的ratherthanspecificthatiseachhasmorethanoneeffectonthegrowthanddevelopmentofplants.Thefivehavesomanysimultaneouseffectsthattheyarenotveryusefulinartificiallycontrollingthegrowthofcrops.Auxinforinstancestimulatestherateofcellelongation拉长causesshootstogrowupandrootstogrowdownandinhibitsthegrowthoflateral侧面的shoots.Auxinalsocausestheplanttodevelopavascular维管的systemtofromlateralrootsandtoproduceethylene. Thepleiotropyofthefivewell-studiedplanthormonesissomewhatanalogous类似的tothatofcertainhormonesinanimal.Forexamplehormonesfromthehypothalamus下五脑inthebrainstimulatetheanterior前面的lobeofthepituitaryglandtosynthesizeandreleasemanydifferenthormonesoneofwhichstimulatesthereleaseofhormonesfromtheadrenal肾上腺的cortex皮质|.Thesehormoneshavespecificeffectsontargetorgansalloverthebody.Onehormonestimulatesthethyroid甲状腺的glandforexampleanothertheovarian子房folliclecellsandsoforth.Inotherwordsthereisahierarchy统治集团ofhormones. Suchahierarchymayalsoexistinplants.Oligosaccharinsarefragmentsofthecellwallreleasedbyenzymes酶:differentenzymesreleasedifferentoligosaccharins.Thereareindicationsthatpleiotropicplanthormonesmayactuallyfunctionbyactivatingtheenzymesthatreleasetheseothermorespecificchemicalmessengersfromthecellwall. Theauthormentionsspecificeffectsthatauxinhasonplantdevelopmentinordertoillustratethe______
NewTechniquePromisesEarlierCancerDetection AnewtechniquecouldrevolutionizetheearlydetectionofcancergivingsufferersagreaterchanceofbeatingthediseaseAmericanscientistssaid.ResearchersattheMassachusettsInstituteofTechnologyhavedevisedanovelmethodof【51】changesinthenucleusofcellsintheearlieststagesofthedisease.Morethan85percentofallcancersoriginateintheepithelium上皮thatlinestheinternalsurfacesoforgans【52】thebody.Althoughthesearetreatable【53】theyarediagnosedinoneofthepreventablestagesearlybodydamagesarealmost【54】todetectsaidscientistFeld.Wepresentanewoptical-probe光学探子techniquebasedonlight-scatteringspectroscopy分光镜检查thatisable【55】detectprecancerousandearlycancerouscellsincell-richepitheliaheaddedinastatement. Thenewtechniquereliesonthefact【56】cellnucleichangeintheearlystagesofcancerandthedifferencesscatterlightinacharacteristicway.Untilnowthechangeswereonlydetectable【57】abiopsy活检wastakenthescientistssaid.Thenewtechnique【58】inthesciencejournalNaturecanbeusedinconjunctionwitharoutinecancerscreeningandsurveillancetechniquewhichusesanendoscope内窥镜—aflexibleopticalprobe【59】withcameraswhichisinsertedintoacavityinthebody—tocheck【60】cancers. Thescientistssaidthey【61】theirnewtechniqueinfourdifferentorgansduringroutineendoscopiccancerscreening.Thetipoftheopticalprobewasbroughtintocontactwiththetissuetobetestedandthescatteringoflightwasrecordedwithouttheneedforanytissuetobe【62】thescientistssaid.Ourresultsshowthatlight-scatteringspectroscopyhasthepotentialtodetectpre-cancerousbodydamagesandpreinvasivecancersthroughoutthebody.Thistechniqueshould【63】improvetheefficiencyofcancerscreeningandsurveillancethescientistssaid.Cancerisoneofthebiggest【64】inindustrializedcountries.【65】tofiguresfromtheWorldHealthOrganization10millionpeoplewerediagnosedwiththediseaseworldwidein1997andsixmilliondied.
GlobalWarmingandTechnologicalchanges Recentstudieshaveidentifiedfourmajorglobalenvironmentalrisks:acidrainozonedepletiondeforestationandthegreenhouseeffect.OnthewholethankstotechnologicalchangespeoplenowtendtomovetowardwarmerregionsinNorthAmericaandEurope.ClimatewarmingwillprobablybeaboontoAlaskawhichisAmerica’’sleastproductivestateinGrossNationalProductGNPpersquaremile. StudiesoftheimpactofglobalwarmingontheUnitedStatesandotherdevelopedregionsfindthatthemostvulnerableareasarethosedependentonunmanagedecosystems—onnaturallyoccurringrainfallrun-offandtemperaturesandtheextremesofthesevariables.Agricultureforestryandcoastalactivitiesfallintothiscategory. Mosteconomicactivityinindustrializedcountrieshoweverdependsverylittleontheclimate.Intensive-careunitsofhospitalscommunicationsheavymanufacturingandmicroelectronicsareamongthesectorslikelytobeunaffectedbyclimaticchange.InselectingwhethertosetupinsayHongKongorinWarsawfewbusinesseswillconsidertemperatureaweightyfactor. GreenhousewarmingwouldhavelittleeffectonAmericasnationaloutput.About3%ofAmericanGNPoriginatesinclimatesensitivesectorssuchasfarmingandforestry.Another10%comesfromsectorsonlymodestlysensitive-energywatersystemspropertyandconstruction.Forthelargestshare87%comesfromsectorsincludingmostservicesthatarenegligiblyaffectedbyclimatechange. Inindustrializedcountriesservicesarescarcelyaffectedbyclimatechanges.
Thegovernmentwouldnotdaretoimposetaxesonsuchnecessitiesasbreadormilk.
NewTechniquePromisesEarlierCancerDetection AnewtechniquecouldrevolutionizetheearlydetectionofcancergivingsufferersagreaterchanceofbeatingthediseaseAmericanscientistssaid.ResearchersattheMassachusettsInstituteofTechnologyhavedevisedanovelmethodof【51】changesinthenucleusofcellsintheearlieststagesofthedisease.Morethan85percentofallcancersoriginateintheepithelium上皮thatlinestheinternalsurfacesoforgans【52】thebody.Althoughthesearetreatable【53】theyarediagnosedinoneofthepreventablestagesearlybodydamagesarealmost【54】todetectsaidscientistFeld.Wepresentanewoptical-probe光学探子techniquebasedonlight-scatteringspectroscopy分光镜检查thatisable【55】detectprecancerousandearlycancerouscellsincell-richepitheliaheaddedinastatement. Thenewtechniquereliesonthefact【56】cellnucleichangeintheearlystagesofcancerandthedifferencesscatterlightinacharacteristicway.Untilnowthechangeswereonlydetectable【57】abiopsy活检wastakenthescientistssaid.Thenewtechnique【58】inthesciencejournalNaturecanbeusedinconjunctionwitharoutinecancerscreeningandsurveillancetechniquewhichusesanendoscope内窥镜—aflexibleopticalprobe【59】withcameraswhichisinsertedintoacavityinthebody—tocheck【60】cancers. Thescientistssaidthey【61】theirnewtechniqueinfourdifferentorgansduringroutineendoscopiccancerscreening.Thetipoftheopticalprobewasbroughtintocontactwiththetissuetobetestedandthescatteringoflightwasrecordedwithouttheneedforanytissuetobe【62】thescientistssaid.Ourresultsshowthatlight-scatteringspectroscopyhasthepotentialtodetectpre-cancerousbodydamagesandpreinvasivecancersthroughoutthebody.Thistechniqueshould【63】improvetheefficiencyofcancerscreeningandsurveillancethescientistssaid.Cancerisoneofthebiggest【64】inindustrializedcountries.【65】tofiguresfromtheWorldHealthOrganization10millionpeoplewerediagnosedwiththediseaseworldwidein1997andsixmilliondied.
Howmanyradioswillyourfactoryturnoutthisyear?
Wehavetothinkverycarefullybeforewetakeanyactionbecauseit'savery{{U}}serious{{/U}}situationwehaveencountered.
AHierarchyofHormones Allofthecellsinaparticularplantstartoutwiththesamecomplementofgenes.Howthencanthesecellsdifferentiateandfromstructuresasdifferentasrootsstemsleavesandfruits?Theansweristhatonlyasmallsubsetofthegenesinaparticularkindofcellareexpressedorturnedonatagiventime.Thisisaccomplishedbyacomplexsystemofchemicalmessengersthatinplantsincludehormonesandotherregulatorymolecules.Fivemajorhormoneshavebeenidentified;auxin生长素abscisicacid脱落酸cytokinin细胞激动素hetylene乙烯andgibberellin赤霉素.Studiesofplantshavenowidentifiedanewclassofregulatorymoleculescalledoligosaccharins. Unliketheoligosaccharinsthefivewell-knownplanthormonesarepleiotropic多向性的ratherthanspecificthatiseachhasmorethanoneeffectonthegrowthanddevelopmentofplants.Thefivehavesomanysimultaneouseffectsthattheyarenotveryusefulinartificiallycontrollingthegrowthofcrops.Auxinforinstancestimulatestherateofcellelongation拉长causesshootstogrowupandrootstogrowdownandinhibitsthegrowthoflateral侧面的shoots.Auxinalsocausestheplanttodevelopavascular维管的systemtofromlateralrootsandtoproduceethylene. Thepleiotropyofthefivewell-studiedplanthormonesissomewhatanalogous类似的tothatofcertainhormonesinanimal.Forexamplehormonesfromthehypothalamus下五脑inthebrainstimulatetheanterior前面的lobeofthepituitaryglandtosynthesizeandreleasemanydifferenthormonesoneofwhichstimulatesthereleaseofhormonesfromtheadrenal肾上腺的cortex皮质|.Thesehormoneshavespecificeffectsontargetorgansalloverthebody.Onehormonestimulatesthethyroid甲状腺的glandforexampleanothertheovarian子房folliclecellsandsoforth.Inotherwordsthereisahierarchy统治集团ofhormones. Suchahierarchymayalsoexistinplants.Oligosaccharinsarefragmentsofthecellwallreleasedbyenzymes酶:differentenzymesreleasedifferentoligosaccharins.Thereareindicationsthatpleiotropicplanthormonesmayactuallyfunctionbyactivatingtheenzymesthatreleasetheseothermorespecificchemicalmessengersfromthecellwall. Thepassagesuggeststhatunlikethepleiotropiohormonesoligosaccharinscouldbeusedeffectivelyto______.
GlobalWarmingandTechnologicalchanges Recentstudieshaveidentifiedfourmajorglobalenvironmentalrisks:acidrainozonedepletiondeforestationandthegreenhouseeffect.OnthewholethankstotechnologicalchangespeoplenowtendtomovetowardwarmerregionsinNorthAmericaandEurope.ClimatewarmingwillprobablybeaboontoAlaskawhichisAmerica’’sleastproductivestateinGrossNationalProductGNPpersquaremile. StudiesoftheimpactofglobalwarmingontheUnitedStatesandotherdevelopedregionsfindthatthemostvulnerableareasarethosedependentonunmanagedecosystems—onnaturallyoccurringrainfallrun-offandtemperaturesandtheextremesofthesevariables.Agricultureforestryandcoastalactivitiesfallintothiscategory. Mosteconomicactivityinindustrializedcountrieshoweverdependsverylittleontheclimate.Intensive-careunitsofhospitalscommunicationsheavymanufacturingandmicroelectronicsareamongthesectorslikelytobeunaffectedbyclimaticchange.InselectingwhethertosetupinsayHongKongorinWarsawfewbusinesseswillconsidertemperatureaweightyfactor. GreenhousewarmingwouldhavelittleeffectonAmericasnationaloutput.About3%ofAmericanGNPoriginatesinclimatesensitivesectorssuchasfarmingandforestry.Another10%comesfromsectorsonlymodestlysensitive-energywatersystemspropertyandconstruction.Forthelargestshare87%comesfromsectorsincludingmostservicesthatarenegligiblyaffectedbyclimatechange. Farmingmustconsiderclimateanasimportantfactor.
It'simpoliteto{{U}}cutin{{/U}}whentwopersonsareholdingaconversation.
Abarehillappearsbehindthejungle.
WecanrelyonJamestocarryoutthismissionforhisjudgementisalwayssound.
Theplannedgeneralstrikerepresentsavitaleconomicchallengetothegovernment.
StressLevelTiedtoEducationLevel PeoplewithlesseducationsufferfewerstressfuldaysaccordingtoareportinthecurrentissueoftheJournalofHealthandSocialBehavior. Howeverthestudyalsofoundthatwhenless-educatedpeopledidsufferstressitwasmoresevereandhadalargerimpactontheirhealth. Fromthisresearchershaveconcludedthattheday-to-dayfactorsthatcausestressarenotrandom.Whereyouareinsocietydeterminesthekindsofproblemsthatyouhaveeachdayandhowwellyouwillcopewiththem. Theresearchteaminterviewedanationalsampleof1031adultsdailyforeightdaysabouttheirstresslevelandhealth.Peoplewithoutahighschooldiplomareportedstresson30percentofthestudydayspeoplewithahighschooldegreereportedstress38percentofthetimeandpeoplewithcollegedegreesreportedstress44percentofthetime. Lessadvantagedpeoplearelesshealthyonadailybasisandaremorelikelytohavedownwardturnsintheirhealth.leadresearcherDr.JosephGrzywaczofWakeForestUniversityBaptistMedicalCentersaidinapreparedstatement.Thedownwardturnsinhealthwereconnectedwithdailystressorsandtheeffectofdailystressorsontheirhealthismuchmoredevastatingforthelessadvantaged. Grzywaczsuggestedfollow-upresearchtodeterminewhyless-educatedpeoplereportfewerdaysofstresswhenitisknowntheirstressismoreacuteandchronic. Ifsomethinghappenseverydaymaybeit’’snotseenasastressorGrzywaczsays.Maybeitisjustlife. stressfuladj.紧张的压力重的 diploman.毕业文凭毕业证书 stressorn.紧张刺激物 devastatingadj.毁灭性的 follow-upn.对病人的随访 The1031adultswereinterviewed______.
Ididn'thelphim.Iwouldhave{{U}}however{{/U}}Ididn'thavethemoney.
TheGrandCanyon StandingontherimoftheGrandCanyon大峡谷gazingacrossthisgiantwoundintheEarth’’ssurfaceavisitormightassumethatthecanyonhadbeencausedbysomeancientconvulsion震动.Infacttheeventsthatproducedthecanyonfarfrombeingsuddenandcatastrophicsimplyadduptotheslowandorderlyprocessoferosion. ManymillionsofyearsagotheColoradoPlateauintheGrandCanyonareacontained1000morefeetofrockthanitdoestodayandwasrelativelylevel.Theadditionalmaterialconsistedofsome14layeredformationsofrock.IntheGrandCanyonregiontheselayerswerelargelywornawayoverthecourseofmillionsofyears. Approximately65millionyearsagotheplateausflatsurfaceintheGrandCanyonareabulgedupwardfrominternalpressuregeologistsrefertothisbulgingactionsupwarding弯曲上升;itwasfollowedbyageneralelevationofthewholeColoradoPlateauaprocessthatisstillgoingon.Astheplateaugraduallyroseshallowriversthatwindedacrossitbegantorunmoreswiftlyandcutmoredefinitecourses.OneoftheseriverslocatedeastoftheupwardwastheancestoroftheColorado.AnotherriversystemcalledtheHualapaiflowingwestoftheupwardextendeditselfeastwardbycuttingbackintotheupwarditeventuallyconnectedwiththeancientColoradoandcaptureditswaters.Thenewriverthenbegantocarveoutthe277-mile-longtrenchthateventuallybecametheGrandCanyon.Geologistsestimatethatthisinitialcuttingactionbegannoearlierthan10millionyearsago. SincethentheCanyonforminghasbeencumulative.Tothecorrosiveforceoftheriveritselfhavebeenaddedotherfactors.Heatandcoldrainandsnowalongwiththevaryingresistanceoftherocksincreasetheopportunitiesforerosions.TheCanyonwallscrumbletheriveracquiresacuttingtool.Tonsofdebrisrainfallrunningoffthehighplateaucreatesfeederstreamsthatcarresidecanyons.Pushingslowlybackwardintotheplateauthesidecanyonsexposenewrocksandthepatternoferosioncontinues. ItcanbeconcludedfromthispassageabouttheGrandCanyonthat______.
StressLevelTiedtoEducationLevel PeoplewithlesseducationsufferfewerstressfuldaysaccordingtoareportinthecurrentissueoftheJournalofHealthandSocialBehavior. Howeverthestudyalsofoundthatwhenless-educatedpeopledidsufferstressitwasmoresevereandhadalargerimpactontheirhealth. Fromthisresearchershaveconcludedthattheday-to-dayfactorsthatcausestressarenotrandom.Whereyouareinsocietydeterminesthekindsofproblemsthatyouhaveeachdayandhowwellyouwillcopewiththem. Theresearchteaminterviewedanationalsampleof1031adultsdailyforeightdaysabouttheirstresslevelandhealth.Peoplewithoutahighschooldiplomareportedstresson30percentofthestudydayspeoplewithahighschooldegreereportedstress38percentofthetimeandpeoplewithcollegedegreesreportedstress44percentofthetime. Lessadvantagedpeoplearelesshealthyonadailybasisandaremorelikelytohavedownwardturnsintheirhealth.leadresearcherDr.JosephGrzywaczofWakeForestUniversityBaptistMedicalCentersaidinapreparedstatement.Thedownwardturnsinhealthwereconnectedwithdailystressorsandtheeffectofdailystressorsontheirhealthismuchmoredevastatingforthelessadvantaged. Grzywaczsuggestedfollow-upresearchtodeterminewhyless-educatedpeoplereportfewerdaysofstresswhenitisknowntheirstressismoreacuteandchronic. Ifsomethinghappenseverydaymaybeit’’snotseenasastressorGrzywaczsays.Maybeitisjustlife. stressfuladj.紧张的压力重的 diploman.毕业文凭毕业证书 stressorn.紧张刺激物 devastatingadj.毁灭性的 follow-upn.对病人的随访 Thelessadvantagedpeoplearethegreater______.
NewTechniquePromisesEarlierCancerDetection AnewtechniquecouldrevolutionizetheearlydetectionofcancergivingsufferersagreaterchanceofbeatingthediseaseAmericanscientistssaid.ResearchersattheMassachusettsInstituteofTechnologyhavedevisedanovelmethodof【51】changesinthenucleusofcellsintheearlieststagesofthedisease.Morethan85percentofallcancersoriginateintheepithelium上皮thatlinestheinternalsurfacesoforgans【52】thebody.Althoughthesearetreatable【53】theyarediagnosedinoneofthepreventablestagesearlybodydamagesarealmost【54】todetectsaidscientistFeld.Wepresentanewoptical-probe光学探子techniquebasedonlight-scatteringspectroscopy分光镜检查thatisable【55】detectprecancerousandearlycancerouscellsincell-richepitheliaheaddedinastatement. Thenewtechniquereliesonthefact【56】cellnucleichangeintheearlystagesofcancerandthedifferencesscatterlightinacharacteristicway.Untilnowthechangeswereonlydetectable【57】abiopsy活检wastakenthescientistssaid.Thenewtechnique【58】inthesciencejournalNaturecanbeusedinconjunctionwitharoutinecancerscreeningandsurveillancetechniquewhichusesanendoscope内窥镜—aflexibleopticalprobe【59】withcameraswhichisinsertedintoacavityinthebody—tocheck【60】cancers. Thescientistssaidthey【61】theirnewtechniqueinfourdifferentorgansduringroutineendoscopiccancerscreening.Thetipoftheopticalprobewasbroughtintocontactwiththetissuetobetestedandthescatteringoflightwasrecordedwithouttheneedforanytissuetobe【62】thescientistssaid.Ourresultsshowthatlight-scatteringspectroscopyhasthepotentialtodetectpre-cancerousbodydamagesandpreinvasivecancersthroughoutthebody.Thistechniqueshould【63】improvetheefficiencyofcancerscreeningandsurveillancethescientistssaid.Cancerisoneofthebiggest【64】inindustrializedcountries.【65】tofiguresfromtheWorldHealthOrganization10millionpeoplewerediagnosedwiththediseaseworldwidein1997andsixmilliondied.
Hisplanshouldsucceedforitseemsquitefeasible.
GlobalWarmingandTechnologicalchanges Recentstudieshaveidentifiedfourmajorglobalenvironmentalrisks:acidrainozonedepletiondeforestationandthegreenhouseeffect.OnthewholethankstotechnologicalchangespeoplenowtendtomovetowardwarmerregionsinNorthAmericaandEurope.ClimatewarmingwillprobablybeaboontoAlaskawhichisAmerica’’sleastproductivestateinGrossNationalProductGNPpersquaremile. StudiesoftheimpactofglobalwarmingontheUnitedStatesandotherdevelopedregionsfindthatthemostvulnerableareasarethosedependentonunmanagedecosystems—onnaturallyoccurringrainfallrun-offandtemperaturesandtheextremesofthesevariables.Agricultureforestryandcoastalactivitiesfallintothiscategory. Mosteconomicactivityinindustrializedcountrieshoweverdependsverylittleontheclimate.Intensive-careunitsofhospitalscommunicationsheavymanufacturingandmicroelectronicsareamongthesectorslikelytobeunaffectedbyclimaticchange.InselectingwhethertosetupinsayHongKongorinWarsawfewbusinesseswillconsidertemperatureaweightyfactor. GreenhousewarmingwouldhavelittleeffectonAmericasnationaloutput.About3%ofAmericanGNPoriginatesinclimatesensitivesectorssuchasfarmingandforestry.Another10%comesfromsectorsonlymodestlysensitive-energywatersystemspropertyandconstruction.Forthelargestshare87%comesfromsectorsincludingmostservicesthatarenegligiblyaffectedbyclimatechange. Climatechangesplayanimportantpartincommunications.
Whatcanyoudoto{{U}}ensure{{/U}}thatyouwillstayhealthy?
NewTechniquePromisesEarlierCancerDetection AnewtechniquecouldrevolutionizetheearlydetectionofcancergivingsufferersagreaterchanceofbeatingthediseaseAmericanscientistssaid.ResearchersattheMassachusettsInstituteofTechnologyhavedevisedanovelmethodof【51】changesinthenucleusofcellsintheearlieststagesofthedisease.Morethan85percentofallcancersoriginateintheepithelium上皮thatlinestheinternalsurfacesoforgans【52】thebody.Althoughthesearetreatable【53】theyarediagnosedinoneofthepreventablestagesearlybodydamagesarealmost【54】todetectsaidscientistFeld.Wepresentanewoptical-probe光学探子techniquebasedonlight-scatteringspectroscopy分光镜检查thatisable【55】detectprecancerousandearlycancerouscellsincell-richepitheliaheaddedinastatement. Thenewtechniquereliesonthefact【56】cellnucleichangeintheearlystagesofcancerandthedifferencesscatterlightinacharacteristicway.Untilnowthechangeswereonlydetectable【57】abiopsy活检wastakenthescientistssaid.Thenewtechnique【58】inthesciencejournalNaturecanbeusedinconjunctionwitharoutinecancerscreeningandsurveillancetechniquewhichusesanendoscope内窥镜—aflexibleopticalprobe【59】withcameraswhichisinsertedintoacavityinthebody—tocheck【60】cancers. Thescientistssaidthey【61】theirnewtechniqueinfourdifferentorgansduringroutineendoscopiccancerscreening.Thetipoftheopticalprobewasbroughtintocontactwiththetissuetobetestedandthescatteringoflightwasrecordedwithouttheneedforanytissuetobe【62】thescientistssaid.Ourresultsshowthatlight-scatteringspectroscopyhasthepotentialtodetectpre-cancerousbodydamagesandpreinvasivecancersthroughoutthebody.Thistechniqueshould【63】improvetheefficiencyofcancerscreeningandsurveillancethescientistssaid.Cancerisoneofthebiggest【64】inindustrializedcountries.【65】tofiguresfromtheWorldHealthOrganization10millionpeoplewerediagnosedwiththediseaseworldwidein1997andsixmilliondied.
NewTechniquePromisesEarlierCancerDetection AnewtechniquecouldrevolutionizetheearlydetectionofcancergivingsufferersagreaterchanceofbeatingthediseaseAmericanscientistssaid.ResearchersattheMassachusettsInstituteofTechnologyhavedevisedanovelmethodof【51】changesinthenucleusofcellsintheearlieststagesofthedisease.Morethan85percentofallcancersoriginateintheepithelium上皮thatlinestheinternalsurfacesoforgans【52】thebody.Althoughthesearetreatable【53】theyarediagnosedinoneofthepreventablestagesearlybodydamagesarealmost【54】todetectsaidscientistFeld.Wepresentanewoptical-probe光学探子techniquebasedonlight-scatteringspectroscopy分光镜检查thatisable【55】detectprecancerousandearlycancerouscellsincell-richepitheliaheaddedinastatement. Thenewtechniquereliesonthefact【56】cellnucleichangeintheearlystagesofcancerandthedifferencesscatterlightinacharacteristicway.Untilnowthechangeswereonlydetectable【57】abiopsy活检wastakenthescientistssaid.Thenewtechnique【58】inthesciencejournalNaturecanbeusedinconjunctionwitharoutinecancerscreeningandsurveillancetechniquewhichusesanendoscope内窥镜—aflexibleopticalprobe【59】withcameraswhichisinsertedintoacavityinthebody—tocheck【60】cancers. Thescientistssaidthey【61】theirnewtechniqueinfourdifferentorgansduringroutineendoscopiccancerscreening.Thetipoftheopticalprobewasbroughtintocontactwiththetissuetobetestedandthescatteringoflightwasrecordedwithouttheneedforanytissuetobe【62】thescientistssaid.Ourresultsshowthatlight-scatteringspectroscopyhasthepotentialtodetectpre-cancerousbodydamagesandpreinvasivecancersthroughoutthebody.Thistechniqueshould【63】improvetheefficiencyofcancerscreeningandsurveillancethescientistssaid.Cancerisoneofthebiggest【64】inindustrializedcountries.【65】tofiguresfromtheWorldHealthOrganization10millionpeoplewerediagnosedwiththediseaseworldwidein1997andsixmilliondied.
AHierarchyofHormones Allofthecellsinaparticularplantstartoutwiththesamecomplementofgenes.Howthencanthesecellsdifferentiateandfromstructuresasdifferentasrootsstemsleavesandfruits?Theansweristhatonlyasmallsubsetofthegenesinaparticularkindofcellareexpressedorturnedonatagiventime.Thisisaccomplishedbyacomplexsystemofchemicalmessengersthatinplantsincludehormonesandotherregulatorymolecules.Fivemajorhormoneshavebeenidentified;auxin生长素abscisicacid脱落酸cytokinin细胞激动素hetylene乙烯andgibberellin赤霉素.Studiesofplantshavenowidentifiedanewclassofregulatorymoleculescalledoligosaccharins. Unliketheoligosaccharinsthefivewell-knownplanthormonesarepleiotropic多向性的ratherthanspecificthatiseachhasmorethanoneeffectonthegrowthanddevelopmentofplants.Thefivehavesomanysimultaneouseffectsthattheyarenotveryusefulinartificiallycontrollingthegrowthofcrops.Auxinforinstancestimulatestherateofcellelongation拉长causesshootstogrowupandrootstogrowdownandinhibitsthegrowthoflateral侧面的shoots.Auxinalsocausestheplanttodevelopavascular维管的systemtofromlateralrootsandtoproduceethylene. Thepleiotropyofthefivewell-studiedplanthormonesissomewhatanalogous类似的tothatofcertainhormonesinanimal.Forexamplehormonesfromthehypothalamus下五脑inthebrainstimulatetheanterior前面的lobeofthepituitaryglandtosynthesizeandreleasemanydifferenthormonesoneofwhichstimulatesthereleaseofhormonesfromtheadrenal肾上腺的cortex皮质|.Thesehormoneshavespecificeffectsontargetorgansalloverthebody.Onehormonestimulatesthethyroid甲状腺的glandforexampleanothertheovarian子房folliclecellsandsoforth.Inotherwordsthereisahierarchy统治集团ofhormones. Suchahierarchymayalsoexistinplants.Oligosaccharinsarefragmentsofthecellwallreleasedbyenzymes酶:differentenzymesreleasedifferentoligosaccharins.Thereareindicationsthatpleiotropicplanthormonesmayactuallyfunctionbyactivatingtheenzymesthatreleasetheseothermorespecificchemicalmessengersfromthecellwall. Accordingtothepassagethefivewell-knownplanthormonesarenotusefulincontrollingthegrowthofcropsbecause______.
NewTechniquePromisesEarlierCancerDetection AnewtechniquecouldrevolutionizetheearlydetectionofcancergivingsufferersagreaterchanceofbeatingthediseaseAmericanscientistssaid.ResearchersattheMassachusettsInstituteofTechnologyhavedevisedanovelmethodof【51】changesinthenucleusofcellsintheearlieststagesofthedisease.Morethan85percentofallcancersoriginateintheepithelium上皮thatlinestheinternalsurfacesoforgans【52】thebody.Althoughthesearetreatable【53】theyarediagnosedinoneofthepreventablestagesearlybodydamagesarealmost【54】todetectsaidscientistFeld.Wepresentanewoptical-probe光学探子techniquebasedonlight-scatteringspectroscopy分光镜检查thatisable【55】detectprecancerousandearlycancerouscellsincell-richepitheliaheaddedinastatement. Thenewtechniquereliesonthefact【56】cellnucleichangeintheearlystagesofcancerandthedifferencesscatterlightinacharacteristicway.Untilnowthechangeswereonlydetectable【57】abiopsy活检wastakenthescientistssaid.Thenewtechnique【58】inthesciencejournalNaturecanbeusedinconjunctionwitharoutinecancerscreeningandsurveillancetechniquewhichusesanendoscope内窥镜—aflexibleopticalprobe【59】withcameraswhichisinsertedintoacavityinthebody—tocheck【60】cancers. Thescientistssaidthey【61】theirnewtechniqueinfourdifferentorgansduringroutineendoscopiccancerscreening.Thetipoftheopticalprobewasbroughtintocontactwiththetissuetobetestedandthescatteringoflightwasrecordedwithouttheneedforanytissuetobe【62】thescientistssaid.Ourresultsshowthatlight-scatteringspectroscopyhasthepotentialtodetectpre-cancerousbodydamagesandpreinvasivecancersthroughoutthebody.Thistechniqueshould【63】improvetheefficiencyofcancerscreeningandsurveillancethescientistssaid.Cancerisoneofthebiggest【64】inindustrializedcountries.【65】tofiguresfromtheWorldHealthOrganization10millionpeoplewerediagnosedwiththediseaseworldwidein1997andsixmilliondied.
NewTechniquePromisesEarlierCancerDetection AnewtechniquecouldrevolutionizetheearlydetectionofcancergivingsufferersagreaterchanceofbeatingthediseaseAmericanscientistssaid.ResearchersattheMassachusettsInstituteofTechnologyhavedevisedanovelmethodof【51】changesinthenucleusofcellsintheearlieststagesofthedisease.Morethan85percentofallcancersoriginateintheepithelium上皮thatlinestheinternalsurfacesoforgans【52】thebody.Althoughthesearetreatable【53】theyarediagnosedinoneofthepreventablestagesearlybodydamagesarealmost【54】todetectsaidscientistFeld.Wepresentanewoptical-probe光学探子techniquebasedonlight-scatteringspectroscopy分光镜检查thatisable【55】detectprecancerousandearlycancerouscellsincell-richepitheliaheaddedinastatement. Thenewtechniquereliesonthefact【56】cellnucleichangeintheearlystagesofcancerandthedifferencesscatterlightinacharacteristicway.Untilnowthechangeswereonlydetectable【57】abiopsy活检wastakenthescientistssaid.Thenewtechnique【58】inthesciencejournalNaturecanbeusedinconjunctionwitharoutinecancerscreeningandsurveillancetechniquewhichusesanendoscope内窥镜—aflexibleopticalprobe【59】withcameraswhichisinsertedintoacavityinthebody—tocheck【60】cancers. Thescientistssaidthey【61】theirnewtechniqueinfourdifferentorgansduringroutineendoscopiccancerscreening.Thetipoftheopticalprobewasbroughtintocontactwiththetissuetobetestedandthescatteringoflightwasrecordedwithouttheneedforanytissuetobe【62】thescientistssaid.Ourresultsshowthatlight-scatteringspectroscopyhasthepotentialtodetectpre-cancerousbodydamagesandpreinvasivecancersthroughoutthebody.Thistechniqueshould【63】improvetheefficiencyofcancerscreeningandsurveillancethescientistssaid.Cancerisoneofthebiggest【64】inindustrializedcountries.【65】tofiguresfromtheWorldHealthOrganization10millionpeoplewerediagnosedwiththediseaseworldwidein1997andsixmilliondied.
GlobalWarmingandTechnologicalchanges Recentstudieshaveidentifiedfourmajorglobalenvironmentalrisks:acidrainozonedepletiondeforestationandthegreenhouseeffect.OnthewholethankstotechnologicalchangespeoplenowtendtomovetowardwarmerregionsinNorthAmericaandEurope.ClimatewarmingwillprobablybeaboontoAlaskawhichisAmerica’’sleastproductivestateinGrossNationalProductGNPpersquaremile. StudiesoftheimpactofglobalwarmingontheUnitedStatesandotherdevelopedregionsfindthatthemostvulnerableareasarethosedependentonunmanagedecosystems—onnaturallyoccurringrainfallrun-offandtemperaturesandtheextremesofthesevariables.Agricultureforestryandcoastalactivitiesfallintothiscategory. Mosteconomicactivityinindustrializedcountrieshoweverdependsverylittleontheclimate.Intensive-careunitsofhospitalscommunicationsheavymanufacturingandmicroelectronicsareamongthesectorslikelytobeunaffectedbyclimaticchange.InselectingwhethertosetupinsayHongKongorinWarsawfewbusinesseswillconsidertemperatureaweightyfactor. GreenhousewarmingwouldhavelittleeffectonAmericasnationaloutput.About3%ofAmericanGNPoriginatesinclimatesensitivesectorssuchasfarmingandforestry.Another10%comesfromsectorsonlymodestlysensitive-energywatersystemspropertyandconstruction.Forthelargestshare87%comesfromsectorsincludingmostservicesthatarenegligiblyaffectedbyclimatechange. Thearticleistalkingabouttheacidrain.
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