简介:在胸腺的中央忍耐是为删除汽车的主要机制反应T房间。尽管有这,进圆周的自我反应的T淋巴细胞的逃跑揭示汽车免疫的威胁。补偿它的瑕疵,胸腺也与镇压功能生产Foxp3+CD4+CD25+规章的T房间的一个自然地发生的子集,能够控制汽车反应房间。Foxp3(叉头框P3),为房间的这个子集的系特定的标记,对他们的thymic开发和外部功能关键,并且还Foxp3驾驶的transcriptional程序直到现在大部分未定义。新兴的证据提供了卓见进它的角色:从Foxp3到的能力与象NFAT那样的另外的抄写因素合作,到目标的染色体宽的描述,基因直接由Foxp3跳了并且调整。这里,我们讨论自然地发生的规章的T房间的发现-他们的显型,发展,维护,和功能-大部分当他们被系特定的标记定义,Foxp3。
简介:CouplingCharacterofPolarizationMaintainingOpticalFiberUndertheConditionofBend①②LIChangchun(NationalLab.ofMolecularandBimolecu...
简介:这份报纸从1950~2003用测量数据在更低的黄河学习在满满的分泌物,侧面的生气的节变化和到来的流动和沉积状况之间的关系。自从1950,满满的分泌物显然减少了,到流动深度的隧道宽度的比率增加了。批评年度平均到来的沉积系数(定义为沉积集中的比率排出)并且分别地,在Huayuankou车站的分泌物为从Huayuankou发生在活动范围到Lijin的没有积聚的免职是约0.012和1,850m3s1。在这个基础上,一个数学模型被用来在不久的将来在可能的到来的流动和沉积条件下面在更低的黄河和它的相应满满的分泌物学习主要隧道的规模。影响主要隧道的规模的主要因素被分析,并且测量塑造并且坚持说一条中型的隧道被讨论。结果显示出在塑造主要隧道上免除Xiaolangdi水库的各种各样的水和沉积联合的效果并且建议在最近的到来的流动和沉积条件下面,与满满的分泌物塑造并且维持一条中型的隧道是可能的近似4,000m3s1。
简介:backgroundBonemarrowmesenchymalstemcells(BMSCs)canbeisolatedandculturedtomanypassages.However,StemcellsincludingBMSCsquicklyundergosenescenceinculture.Thecellsenescenceandmulti-directionaldifferentiationhavehamperedproducingBMSCsinquantitywiththeirundifferentiatedstate.Inthisstudywereportanaturalcompound,vitaminC(Vc),maintainsBMSCsstemproperty.MethodsHumanBMSCswereisolatedfrombonemarrowandpurifiedby1.073g/mLdensitygradientcentrifugation.50ng/mLVcwereaddedtoBMSCsfordifferenttimepoint.FlowcytometrywasusedtodetectcellsurfacemarkersofBMSCswithorwithoutVctreatment.BMSCsproliferationwasanalyzedbyMTTassay.PCR(polymerasechainreaction)andreal-timePCRwereusedfordetectingc-kit,nanog,andOct-4genesexpressionlevels.DNAmethyltransferase(Dnmt)1andDnmt3blevelswerealsodetectedbyreal-timePCR.ResultsFlowcytometryshowedthatafterVctreatmentfor6h,thesurfacemarkersofBMSCswerealmostunchanged.VcincreasedtheproliferationactivityofBMSCsfrom6hto24h.PCRshowedtheexpressionofc-kit,nanog,andoct-4geneswereobviouslyincreasedinVctreatedgroupthancontrolgroupat12h.Real-timePCRshowedthatthelevelofc-kit,nanog,andoct-4geneswereunregulatedfrom6hto12hcomparedwithcontrolgroup.VcalsoincreasedDnmt3bbutnotDnmt1geneexpression.ConclusionsOurresultsshowedVcactsatleastacceleratesBMSCsproliferationandmaintainsstemcellproperty.Inourstudy,wehighlightedamethodofimprovingthespeedofBMSCsgenerationandprovidedadditionalinsightsintothemechanisticbasisofpreventingBMSCssenescence.
简介:Wepresentapolarization-maintainingPANDAring-corefiber(PM-PRCF)characterizedbythecombinationofaring-corestructurewithtwostress-applyingrods.Thisspecialfiberdesignseparatestheadjacentmodesandavoidsthecutoffofthehigher-ordermodes,whichisacommonprobleminellipticalcorepolarization-maintainingfew-modefibers.Usingahigh-contrastindexringandstress-inducedbirefringence,thePM-PRCFfeaturessupportfor10vectormodes,witheffectiverefractiveindexseparationsfromtheiradjacentmodes>10-4.Broadbandperformanceisinvestigatedsubsequentlyoverawidewavelengthrangefrom1500to1630nm.Theproposedfiberistargetedatapplicationsinspace-divisionmultiplexingwhileeliminatingthecomplexmultiple-inputmultiple-outputsignalprocessing.
简介:Anewmethodisproposedtogeneratemicrowaveandmillimeter-wavebyusingpolarizationscramblerandpolarizationmaintainingfiber(PMF),whichisbasedonthecouplingandtheinteractionbetweenthetwopolarizationsoftheinitialnon-chirpGaussianopticalpulseinPMF.Theexpressionsofthemicrowaveandmillimeter-wavearederivedbycouple-modetheory.Moreover,thefeasibilityisanalyzedsimulatedly.Atlast,0-120GHzmicrowaveandmillimeter-wavecanbeproducedbyadjustingsystemparameterorinputpulseduration.Theprojectisofgreatsimplicity,stabilityandhighexportefficiency.
简介:Influenceofthermal-mechanicalpropertiesonthefeaturesofthepandapolarization-maintainingopticalfiber(PMF)infabricationprocessisstudiedindetailbyfiniteelementmethod(FEM).Thestressbirefringenceis2.13443×10-4obtainedbythestaticanalysisand2.1269×10-4bydynamicanalysis.Thedifferenceinsimulationbytwomethodsisaround0.4%.Thenon-uniformityofstressbirefringenceinthefibercoreisabout1.6%.Predictedresultsdemonstratethateffectofthethermalconductiveparameteronfiberthermalstressdominates.Thehighanduniformstressbirefringenceinthefibercoreisobtainedbyappropriatelyselectingsuitablestressregionareaandposition.
简介:Weproposeanovelwaveguidedesignofpolarization-maintainingfewmodefiber(PM-FMF)supporting≥10non-degeneratemodes,utilizingacentralcircularairholeandacircumjacentelliptical-ringcore.Thestructureendowsanewdegreeoffreedomtoadjustthebirefringenceofalltheguidedmodes,includingthefundamentalpolarizationmode.Numericalsimulationsdemonstratethat,byoptimizingtheairholeandelliptical-ringcore,aPM-FMFsupporting10distinctivepolarizationmodeshasbeenachieved,andtheeffectiveindexdifferenceΔneffbetweentheadjacentguidedmodescouldbekeptlargerthan1.32×10-4overthewholeC+Lband.TheproposedfiberstructurecanflexiblytailoredtosupportanevenlargernumberofmodesinPM-FMF(14-modePM-FMFhasbeendemonstratedasanexample),whichcanbereadilyapplicabletoascalablemodedivisionmultiplexingsystem.
简介:AfteroperationoftheThreeGorgesProject(TGP),thereisanewevolutiontendencyforriversandlakesinthemiddlereachesoftheYangtzeRiver(i.e.theChingRiverreaches).Inrecentyears,theweakeningconnectionrelationshipbetweentheYangtzeRiverandDongtingLakehasresultedinaseriesofproblemsforfloodregulation,waterresourcesutilization,andaquaticecosystemprotectionintheriver-lakejointarea.Inthispaper,thehydrologicalcharacteristicsandfluvialprocesseswithintheriver-lakejointareaarestudied,andpossiblemanagementstrategiestomaintaintheconnectedriver-lakerelationshipareproposed.Toachievethisobjective,theevolutiontendency,suchasthezero-flowproblemandriverregimeforthreemajoroutlets(i.e.theSongziOutlet,TaipingOutlet,andOuchiOutlet)toDongtingLakefromtheYangtzeRiver,isanalyzed.ItisbelievedthattheSongziOutlethasacomparativeadvantageinflowdiversionovertheothertwooutlets.TheRangeofVariabilityApproachisintroducedtoidentifyhydrologicalcharacteristicsattheSongziOutlet.Severalcharacteristicvaluesofflowdiversionfromthisoutletduringdroughtperiodsaredetermined.Then,thefluvialprocessesintheriver-lakejointareaarestudiedbycomparingtopographicmapsandusingcontrolgaugestationdataofvariousyears.ThewaterandsedimentfluxareanalyzedbeforeandafteroperationoftheTGP.Finally,basedontheresultsobtained,twopossiblemanagementstrategiesarerecommendedandcorrespondingparametersareestimatedtostrengthenandmaintaintheconnectedriver-lakerelationship.ThisanalysistakesintoaccountoperationoftheTGP,mainstreamshiftandincreasingriverbedscourintheChingRiverchannel.Torestoretheflowdiversionconditiontothatinthe1950sor1960s(i.e.140m3/sofflowdiversioncorrespondingto5500m3/sofflowattheZhichengstation),itisestimatedthattheriverchannelaroundtheSongziOutletshouldbedredged1.4munderthecurrentriverbedsituatio
简介:Heatshockprotein70(HSP70)maintainsCa~(2+)homeostasisinPC12cells,whichmayprotectagainstapoptosis;however,themechanismsofneuroprotectionareunclear.Therefore,inthisstudy,weexaminedCa~(2+)levelsinPC12cellstransfectedwithanexogenouslentiviralHSP70geneexpressionconstruct,andwesubsequentlysubjectedthecellstoischemia-hypoxia/reoxygenationinjury.HSP70overexpressionincreasedneuronalviabilityandATPaseactivity,anditdecreasedcellularreactiveoxygenspecieslevelsandintracellularCa~(2+)concentrationafterhypoxia/reoxygenation.HSP70overexpressionenhancedtheproteinandmRNAexpressionlevelsofsarcoplasmic/endoplasmicreticulumCa~(2+)-ATPase(SERCA),butitdecreasedtheproteinandmRNAlevelsofinositol1,4,5-trisphosphatereceptor(IP3R),therebyleadingtodecreasedintracellularCa~(2+)concentrationafterischemia-hypoxia/reoxygenation.TheseresultssuggestthatexogenousHSP70protectsagainstischemia-hypoxia/reoxygenationinjury,atleastinpart,bymaintainingcellularCa~(2+)homeostasis,byupregulatingSERCAexpressionandbydownregulatingIP_3Rexpression.
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简介:Ischemicpreconditioningelicitedbyanon-fatalbriefocclusionofbloodflowhasbeenappliedforanexperimentaltherapeuticstrategyagainstasubsequentfatalischemicinsult.Inthisstudy,weinvestigatedtheneuroprotectiveeffectsofischemicpreconditioning(2-minutetransientcerebralischemia)oncalbindinD28kimmunoreactivityinthegerbilhippocampalCA1areafollowingasubsequentfataltransientischemicinsult(5-minutetransientcerebralischemia).AlargenumberofpyramidalneuronsinthehippocampalCA1areadied4daysafter5-minutetransientcerebralischemia.IschemicpreconditioningreducedthedeathofpyramidalneuronsinthehippocampalCA1area.CalbindinD28kimmunoreactivitywasgreatlyattenuatedat2daysafter5-minutetransientcerebralischemiaanditwashardlydetectedat5dayspost-ischemia.IschemicpreconditioningmaintainedcalbindinD28kimmunoreactivityaftertransientcerebralischemia.Thesefindingssuggestthatischemicpreconditioningcanattenuatetransientcerebralischemia-causeddamagetothepyramidalneuronsinthehippocampalCA1areathroughmaintainingcalbindinD28kimmunoreactivity.