简介:1 如果有一天,有人问你要不要去做亲子鉴定,从而进一步证明你与父母或子女的血缘关系,抑或权当是好玩,去检验一下现代科学技术是否可靠,你一定不会认为这是一个乐于让人接受的愉快的建议。人类发展到今天,还没有任何一项技术像DNA鉴定一样,犹如一面魔镜,能如此不容置疑地反映出我们现存生活状态的某种真相,并使人产生一种畏惧感。人生就像棋局,我们已经从我们的人生经历中接受了许多既成的事实,并基于对这些事实的认识和有关法律、道德、伦理、家庭等方面的文化传统建立起了我们对生活的信念,我们并不想对此产生怀疑,颠覆我们原有的生活理念和秩序。然而,大千世界,众生芸芸,并不是所有的人生都遵循着传统的生活模式和法则
简介:Someantitumoractivitiesofcomponent(E),extractedfromtherootofFagopynumCymosum(Trev)Meisn(FCTM),haverecentlybeendiscoveredinvivoandinvitro.ThecomponentE(CE)’spatternofactionwithtumorcellularDNAatthemolecularpharmacologicallevelwasinvestigatedbymacromolecularsynthesisexperiment(MSE)andhumanDNAinteractionsystemestablishedinourlaboratory.Theexperimentsdemonstratedthat,invitro,theagentcouldmarkedlyinhibittheincorporationof3H-TdRintothecellularDNA,andtheIC50inP388leukemiacellandinSGC-7901cellwas17.86μg/mland110.4μg/ml,respectively.Theagent,atmg/mllevel,couldproduceanintercalationreversionpatternwithDNAwithinashorttime(2hours).Butwhentheintervalwasprolongedforover4hours,theactionchangedtointercalationirreversiblepattern.Accordingtotheseobservations,theauthorsinferthatCEinteractswithDNAintwoways-directlyandindirectly.Theindirectaction,especiallyinlowconcentr
简介:目的探讨骨骼DNA提取与快速检验的方法.方法取1年内的碎骨片37份,采用优化的PrepFilerBTAForensicDNA试剂盒法提取DNA,以GlobalfilerTMExpress复合扩增,经3130xL基因分析仪电泳分离进行STR分型检测.结果37份骨骼样本均获得完整的STR分型,各等位基因峰为200~7500rfu,峰型较均衡.结论采用本文建立的骨骼DNA快速检验法提取骨骼DNA,检验时间短,STR分型结果好,可在实际检案中使用,特别适合于灾害事故遇难者身份识别(disastervictimidenti?cation,DVI)的身源鉴定.
简介:Themitochondrial12SrRNAhasbeenshowntobethehotspotformutationsassociatedwithbothaminoglycoside-inducedandnon-syndromichearingloss.Ofallthemutations,thehomoplasmicA1555GandC1494Tmutationsatahighlyconserveddecodingregioninthe12SrRNAhavebeenassociatedwithaminoglycoside-inducedandnon-syndromichearinglossinmanyfamiliesworldwide.TheA1555GorC1494Tmutationisexpectedtoformnovel1494C-G1555or1494U-A1555base-pairatthehighlyconservedA-siteof12SrRNA.ThesetransitionsmakethesecondarystructureofthisRNAmorecloselyresemblethecorrespondingregionofbacterial16SrRNA.Thus,thenewU-AorG-Cpairin12SrRNAcreatedbytheC1494TorA1555Gtransitionfacilitatesthebindingofaminoglycosides,therebyaccountingforthefactthattheexposuretoaminoglycosidescaninduceorworsenhearinglossinindividualscarryingthesemutations.Furthermore,thegrowthdefectandimpairmentofmitochondrialtranslationwereobservedincelllinescarryingtheA1555GorC1494Tmutationinthepresenceofhighconcentrationofaminoglycosides.Inaddition,nuclearmodifiergenesandmitochondrialhaplotypesmodulatethephenotypicmanifestationoftheA1555GandC1494Tmutations.TheseobservationsprovidethedirectgeneticandbiochemicalevidencesthattheA1555GorC1494TmutationisapathogenicmtDNAmutationassociatedwithaminoglycoside-inducedandnonsyndromichearingloss.Therefore,thesedatahavebeenprovidingvaluableinformationandtechnologytopredictwhichindividualsareatriskforototoxicity,toimprovethesafetyofaminoglycosideantibiotictherapy,andeventuallytodecreasetheincidenceofdeafness.
简介:目的:用荧光定量聚合酶链反应(FQ-PCR)法准确地定是检验血清中乙型肝炎病毒(HBV)的数量和免疫指标,以指导临床。方法:采用HBV-DVAFQ-PCR诊断试剂盒,以一种完全闭管式的PCR和荧光探针杂交技术组合所产生的实时检验定量PCR方法,检测了58例临床血清标本。结果:经FQ-PCR检测,9例HBV的HBsAg、HBeAg、HBcAg、HBcAb都阳性标本,其HBV-DNA的阳性率为100%,平均HBV-DNA拷贝数为2.0×10^8/ml;16例HBsAg、HBeAb、HBcAb都阳性的标本,其阳性率为62.5%(10例),平均拷贝数为5.2×10^5/ml,而常规PCR只有33%的阳性率;7例HBsAb、HBeAb、HBcAb都阳性的标本,其阳性率为14.3%(1例),平均拷贝数为4.7×10^3ml。结论:HBV-DNA的FQ-PCR检测较常规PCR更具有较高的灵敏度和特异性,且定量准确,结果可靠,能够避免PCR后处理导致物假阳性污染,可以真实反映HBV的感染和低复制状态,对于乙型肝炎的临床诊断,治病方案的选择和疗效观察有较大的指导意义。
简介:AdoublehelixmodelofchargetransportinDNAmoleculeisgivenandthetransmissionspectraoffourDNAsequencesareobtained.ThecalculatedresultsshowthatthetransmissioncharacteristicsofDNAarenotonlyrelatedtothelongitudinaltransportbutalsotothetransversetransportofmolecule.Theperiodicsequencewiththesamecompositionhasstrongerconductionability.Withtheincreasingofbasescomposition,theconductiveabilityreduces,buttheweightofθdirectionrisesinchargetransfer.
简介:The2004SoutheastAsiaTsunamikillednearly5,400peopleinSouthernThailand,includingforeigntouristsandlocalresidents.TorecoverDNAevidenceasmuchaspossiblefromtheseriouslydecomposedbodies,weexploredproceduresofsamplepreparationfrombothboneandtoothsamplesaswellasbothmitochondrialandnuclearmarkers.DespitehavingfailedtorecoverenoughDNAfornuclearmarkertyping,wesucceededinobtainingfullyinformativeresultsformitochondrialmarkers(HV1andHV2)from258toothsampleswithasuccessrateof51%(258/507).UsinganorganicDNAextractionmethodcoupledwithanultrafiltrationstep,weobtained16STR(including13CODISloci,onesexdiscriminationlocus,andtwoIdentifilerloci)profilesfor834sampleswithasuccessrateof79%(834/1,062).Inaddition,bycomparingtheallelicfrequenciesbetweenthetypedsamplesasagroupandotherindexpopulations,weconcludethattheThaitsunamivictimsareacombinedgroupofseveralpopulations.Ourresultsprovidevaluableevidenceandprotocolsforthefutureforensicpractice.