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  • 简介:表观遗传学的研究表明,脑肿瘤细胞中某些基因的高甲基化可以用来标记肿瘤预后,甲基化后的沉默产物可作为化疗反应的生物标记分子,而对DNA甲基化抑制剂的研究已成为肿瘤治疗的新方向。总之,在脑肿瘤的发生和发展中。DNA甲基化起着重要的作用。本文总结了肿瘤甲基化方面的最新进展。

  • 标签: 脑肿瘤 DNA甲基化抑制剂 表观遗传学 肿瘤预后 高甲基化 肿瘤细胞
  • 简介:Electrophoresis,chromatography,immunoassay,sequencingandothertimeconsumingap-proacheshavebeendevelopedtodetermineDNAbasemismatching,oxidativelesionorstrandbreaks.Sometimes,however,onlyqualitativeinformationisenoughtodecidewhethermutationhashappenedtoDNAanditsextent.Convolutionspectrometry(CS),anewtechniquetodiscoverultrafmedifferenceonultraviolet(UV)absorptionofdifferentsubstances,isoriginallyemployedtofindoutanysubtlemutationofDNAinducedbyUVradiation.Muta-tiveDNAiscomparedwithegocriteriabasedonthespectraoftheformerDNA,anydifferenceisquantitativelyex-pressedbydispersion(5).Visiblechangescannotbeobservedonsecond-derivativespectrauntilthemutationgets5upto11.48%.DimethylsulfoxideisanintensifierofUV254nminducedDNAmutationandprotectorat365nm,whichissimplyconfirmedbyincreasinganddecreasing5.Everyconvolutionproceduretakeslessthan1min.Convolutionspectrometryprovidesafast,simple,sensitiveandinexpensivealternativetodetermineDNAmutation,andtoscreenanti-mutationalmedicines.

  • 标签: DNA UV CS
  • 简介:Adetectionofanthracyclineantitumordrugdaunomycin(DNR)reactingwithDNAinsimulatemetabolisminvitrohasbeenmade.ItwasfoundthatDNRcouldreactwithDNAtoformDNR-DNAadducts.TheadductcompositionsofDNRwithfishspermDNAandthermallydenaturatedDNAweredetermined.TheequilibriumassociationconstantKofDNRwithfishspermDNAis1.98×10^5L/molandthatofDNRwithdenaturatedDNAis2.29×10^4L/mol.Semiquinonefreeradicals,metabolicproductsofDNR,candestroybothfishspermDNAanditsthermallydenaturatedDNA.ItisverifiedbyhyperchromiceffectincreaseobservedinUVspectrumandAFMexperiments.ThemechanismofDNAdegradationhasalsobeeninvestigated.Resultsobtainedallowonetoexplainthereasonofsideeffectofanthracyclinedrugandgivethewaytodepress,whichwereofclinicalsignificance.

  • 标签: 抗癌药物 道诺霉素 DNA 新陈代谢物 光谱化学分析
  • 简介:Eelfamilyisahugeone,inwhichmanykindsofeelsespeciallysomemigratoryeels,bearstrongresemblancetoeachother,andarethereforedifficulttobeidentified.Inthisstudy29randomprimerswereusedtomakeRAPDanalysisforJapaneseseel(Anguillajaponica),Europeaneel(Anguillaanguilla)andPikeeel(Muraenesoxcinereus).Andtotally299fragmentswerecounted.Sharedorspecificfragmentswerecountedandgeneticsimilarityorgeneticdistancewerecalculated.ThegeneticsimilaritybetweenJapaneseeelandPikeeelis0.68andthegeneticdistancebetweenthemis0.32;thosebetweenEuropeaneelandPikeeelare0.72and0.28respectively,andbetweenJapaneseeelandEuropeaneelare0.74and0.25respectively.Themethodhasbeenshowntobesuitabletomolecularidentificationofeels.Itprovidesanalternativeapproachtodeterminetherelationshipbetweenspecies.

  • 标签: 随机扩增多态性DNA分析 鳗鱼 种类 遗传距离 分类
  • 简介:AvohammetricstudyoftheinteractionofneutralRed(NR)withDNAatagoldelectrodeinaphosphatebuffersolutionisdescribed.AfteraddingDNAinanNRsolution,thereductionpeakcurrentofNRdecreases.ThebindingmeehahismsofNRtoDNAindifferentpHrangesaredifferent.ThereductionpeakpotentialofNRinapH7.0phosphatebuffersolutioninthepresenceofDNAshiftspositively,indicatingthatthebindingofNRtoDNAisintercalationaction,butatpH=6.0thereductionpeakpotentialofNRshiftsnegatively,indicatingthatthebindingofNRtoDNAiselectrostaticaction.TheformedcomplexesareDNA-NRwhen[NR]/[DNA]<0.18andDNA-3NRwhen[NR]/[DNA]>0.35,respectively.

  • 标签: 中性红 DNA 循环伏安法 相互作用 核酸 信息复制
  • 简介:DNA聚合酶III是为DNA的复制负责的五eubacterialDNA聚合酶之一双。在DNA聚合酶III核心酶的十个子单元之中,高山哈子单元两个都为polymerizing催化反应DNA海滨。在这研究,我们提取了高山的genomic序列哈从159的子单元定序eubacterial染色体,并且执行了基于顺序的种系发生、结构的分析。我们发现所有eubacterial染色体有至少一座高山哈子单元,哪个形式homodimers或heterodimers。种系发生并且领域高山的结构的分析以及拷贝数字变化哈在每个细菌的子单元显示高山的分类哈子单元进四个基本的组:polC,dnaE1,dnaE2,和dnaE3。这个分类具有在染色体作文分析的本质。我们也巩固了命名惯例在基因注解避免进一步的混乱。

  • 标签: 真细菌 DNA聚合酶Ⅲ Α亚基 基因组 氨基酸序列 比较分析
  • 简介:应用DNA技术开展警犬优良品种保纯和培育,是提高我国警犬技术工作科技含量的重要举措,对于促进我国警犬技术与国际警犬技术接轨,通过警犬DNA数据库对警犬资源的遗传质量进行实时监测和管理,在保持我国警犬技术的可持续发展中将发挥重要作用.

  • 标签: DNA技术 警犬 应用 前景 DNA数据库 可持续发展
  • 简介:1案例简介2002年1月5日凌晨,宜昌市某村发生一起蒙面入室抢助案,受害人罗某夫妇被一伙蒙面歹徒持刀砍伤,并抢走部分财物。接到报案后,区公安分局侦技人员立即赶赴现场开展侦破工作,经勘察现场,仅在距中心现场60余米处的一田坎下提取到数枚烟头,同时在侦察中发现外来人员向某与李某有作案嫌疑,但李某去向不明,传唤向某,因无

  • 标签: 烟头 DNA 鉴定 破案 唾液 案例
  • 简介:Moleculardynamics(MD)simulationsareperformedtostudyadhesionandpeelingofashortfragmentofsinglestrandDNA(ssDNA)moleculefromagraphitesurface.Thecriticalpeel-offforceisfoundtodependonboththepeelingangleandtheelasticityofssDNA.FortheshortssDNAstrandunderinvestigation,weshowthatthesimulationresultscanbeexplainedbyacontinuummodelofanadhesiveelasticbandonsubstrate.Theanalysissuggeststhatitisoftenthepeakvalue,ratherthanthemeanvalue,ofadhesionenergywhichdeterminesthepeelingofananoscalematerial.

  • 标签: 分子动态模拟 DNA 培养基 表面支持 弹性模型
  • 简介:MtDNAwassuccessfullyextractedfromtenindividualbones(femurs)inthetombsofancientJushiinTurfanbasin,datedbacktotheyearabout3000-2500yearsago.Bymeansoffouroverlappingprimers,wegotnucleotidesequenceofthe218bplength.AncientmtDNAwasanalyzedbythesequencingofhypervariableregionⅠofthemtDNAcontrolregion.Theresultshowsthat9haplotypeswith24polymorphicsiteswereobtained.ThephylogeneticanalysisindicatedthatMongoliansandAltaiarethepopulationgeneticallyclosesttotheJushigroupsandJushimtDNApoolbeinganadmixtureofeasternAsianandEuropeanlineages.SoourpreliminarydataimplythatanancientminglingofEuro-AsianpopulationhadexistedinTurfanbasinpriortotheearlyIronAge.

  • 标签: ANCIENT DNA Sequence PHYLOGENETIC ANALYSIS
  • 简介:Rheumatoidfactors(RFs)arethecharacteristicautoantibodiesofrheumatoidarthritis.Recentresearchesinourlaboratoryshowedthattheimmobilizedsingle-strandedDNA(ss-DNA)immunoadsorbentcanselectivelyremoveRFsfromtheserumofpatients.Inthepresentpaperarestudiedthemodificationofargininine,tryptophan,lysineresiduesandcarboxylterminusofIgGRF,whichwasseparatedfrompatients′serum,with1,2-cyclohexanedione(CHD),N-bromosuccinimide(NBS),pyridoxal5′-phosphate(PP)and1-ethyl-3-(3-dimethylaminopropyl)-carbodiimide(EDC)respectively,andtheireffectsontheadsorptioncapacityoftheimmobilizedss-DNAimmunoadsorbentforIgGRF.Afterthespecificmodification,thecorrespondingadsorptioncapacitiesoftheadsorbentswerechangedfrom48%,46%,44%and54%to84%,14%,21%and81%,respectively.Theseresultsindicatethattheelectrostaticorionic-bondingisessentialfortheinteractionbetweenss-DNAandIgGRF.

  • 标签: 交互作用 风湿症 固定单链DNA 免疫吸附 1 2-环己二酮 N-四溴酚酞磺酸钠
  • 简介:TheroleplayedbyDNAinmolecularbiologyisclearlyrecognizedtobevitaltolifeonthisplanet.8-oxo-7,8-dihydro-2deoxyguanosine(=8-OHdG),isprobablythemostimportantproductof"oxidativestress”inDNA.ItsconcentrationinDNAis,infact.aquantitativeanalysisofthedegreeofDNAdamagethatanorganismhasundergone.Duetotheimportanceof8-OHdGofnucleicacidginmutagenesis,carcinogenesisandaging,numerouschemicalandbiologicalinvestigationshavebeenmadeonthissubjectinthepasttime.Kuchinoandco-workershavefoundthat8-OHdGresidueinDNAismisreadingduringtheprocessofDNAreplication.Recently,somereportshavebeenpresentedonhigh8-OHdGlevelsinpatientssufferingfromvariousdiseasessuchaschronichepatitis,Fanconisanemia,diabetesmellitusandHelicobacterpyloriinfections.Asaresult,8-OHdGisausefulmarkerforthestudyofDNAdamagearisingfromreactiveoxygenspeciesandisofgreatsignificanceforcancerresearch.The8-OHdGlevelsinDNAcanhelpunderstandthemechanismofcarcinogensandleadtomoreeffectivetreatmentsformanydifferenttypesofcancer.Forthesereasons,ananalysisof8-OHdGwithquickness,lowcostandhighaccuracyisrequired.

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  • 简介:一个简单协议用变白的稻秧为脱氧核糖核酸抽取被建立,米饭脱氧核糖核酸由此直接在单个eppendorftube在0.5mol/LNaOH答案被提取。比较PCR分析和电气泳动的结果证明用这个方法提取的脱氧核糖核酸象那个使用的标准CTAB方法同样好、有用。

  • 标签: 水稻 聚合酶 分子标记 PCR分析 基因序列
  • 简介:美国惠普公司和洛杉矶加利福尼亚大学的科学家们近日宣布,他们攻克研制分子计算机芯片的重大难羌的一项技术已经获得专利白宫的国家纳米技术研究计划的负责人米哈伊尔·罗利评价公布的这项发明“是在研制真正的分子电路的关键一步”。

  • 标签: 分子电路 机芯 芯片 美国惠普公司 研究计划 发展