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目的 通过筛查人21号染色体上的杂合型单核苷酸多态性(single nucleotide polymorphism,SNP)位点,初步建立基于定量焦磷酸测序反应的唐氏综合征分子诊断方法.方法 基于改进引物设计的等位基因特异性扩增法,在21号染色体上选取7个SNP位点进行杂合子筛选,通过焦测序法检测SNP中两个等位基因型的比值,并作为诊断唐氏综合征的依据.结果 通过对84名正常中国人基因组样本进行筛查,得到6个杂合率较高的SNP位点.6个SNP位点的杂合子覆盖率为92.9%.应用这6个SNP位点对10例唐氏综合征患者的样本进行了焦测序定量检测,结果表明10例患者样本中有9例样本的两个基因型比值为2:1或1:2,1例未检出杂合子,检出率为90%.结论 初步建立了一种唐氏综合征辅助诊断方法,具有成本低、操作简单、快速和结果明了的优点,可以有效地快速诊断唐氏综合征,为今后进一步完善该方法,并将其用于临床诊断奠定了基础. 相似文献
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产前诊断对于预防及控制新生儿发病率具有十分重要的意义.目前,大多数的产前诊断方法对孕妇和胎儿具有潜在的损伤,所以临床医生一直在寻找新的无创性产前诊断技术.研究表明胎儿细胞存在于孕妇外周血中,但由于其数量较少,而且存在个体差异,因此很难应用于临床.最近的研究发现母体血浆或血清中存在高浓度的游离胎儿DNA.近年来,随着分子生物学技术的发展,从孕妇血浆或血清中检测胎儿DNA并应用于临床成为可能,为无创性产前诊断开辟了一种新途径.本文着重介绍游离胎儿DNA的来源、特点及在无创性产前诊断中的应用. 相似文献
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尖吻蝮蛇蛇毒类凝血酶Agacutin的亚基的拆分和氨基酸残基测序 总被引:1,自引:0,他引:1
目的 测定Agacutin两个相近亚基的N端15个氨基酸残基序列,酶分子的2个亚基需拆分以获得亚基单肽链并测序.方法 通过生物化学方法获得高纯化Agacutin,经SDS-PAGE电泳分离、亚基胶条回收及PVDF膜电转移技术等方法制备了可供鉴定和测序的单亚基样品,后者通过Edman降解法,测定了亚基N端15个氨基酸残基序列.结果 大亚基(16 kDa)的序列为:DCSSGWSSYEEHQYY,小亚基(15kDa)序列为DSSGWSSYEGHEYYV.结论 测序结果经NCBI数据库检索发现,Agacutin为新的蛇毒类凝血酶. 相似文献
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目的比较不同粪便DNA提取试剂盒及粪便样本不同储存时间对粪便人基因组DNA提取效率的影响。方法对18例体检健康者使用QIAamp DNA Stool Mini Kit,MO BIO UltraCleanFecal DNA Isolation Kit,E.Z.N.A.Mag Bind Stool DNA Kit 3种粪便DNA提取试剂盒进行粪便DNA提取,通过紫外分光光度法对总DNA产量和纯度进行分析,通过实时荧光聚合酶链反应(PCR)方法对提取产物中结肠腺瘤性息肉病基因进行定量,并比较人基因组DNA提取效率的差异及不同样本储存时间对其影响。结果在3种试剂盒中,QIAamp DNA Stool Mini Kit对人基因组DNA的提取产量最高(平均67.81 ng/g),E.Z.N.A.Mag Bind Stool DNA Kit提取产物纯度最高(A260/A280平均2.07),MO BIO UltraCleanFecal DNA Isolation Kit操作耗时最短(约40 min);粪便样本在-70℃条件下储存30 d内,不同储存时间对总DNA提取效率差异有统计学意义(P0.01)。结论 QIAamp DNA Stool Mini Kit对粪便人基因组DNA的提取效率最高,且于-70℃储存粪便样本30 d内对人基因组DNA提取效率无影响。 相似文献
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Objective To design a device based on immunobead method which enables extraction of exfoliated colonocytes from human feces to become an automatic concentrating process. Methods The automatic device for extraction of exfoliated colonocytes from human feces was designed based on the composition and physiochemical features of the feces as well as the distribution of exfoliated colonocytes, so as to integrate its functions in sample collection, pretreatment, exfoliated colonocyte-immunobead binding,and exfoliated colonocyte- immunobead complex washing. The immunobeads were prepared by coating magnetic beads with monoclonal antibody of epethelial cell adhesion molecule (EpCAM) Ber-EP4 and used to concentrate colorectal cancer cells from cell culture. The binding of colorectal cells to immunobeads was observed under microscopy. Cancer tissues of 10 colorectal cancer patients (or tissues around cancer) were collected. The automatic device for extraction of exfoliated colonocytes from human feces was used to get exfoliated cells from stool specimens of the patients. QRT-PCR was used to detect gene expression of c-myc、cox-2、CD44v6 in tissues and cells collected. Rate of gene positive expression of different original specimens was compared. Results The automatic device for extraction of colonocytes from human feces was designed and manufactured. Extracting exfoliated coloncytes from feces sample was successfully completed by the automatic device and self-prepared immunobeads with coating special monoclonal antibody. The recovery rate of cells was 27%. Rate of c-myc, cox-2 and CD44v6 gene positive expression in cancer tissues or tissues around cancer was 20%, 10% and 20% respectively, and 100% in exfoliated cells from stool specimens. The difference of positive rate among specimens was significant (all P<0.01). Exfoliated cells from stool specimens collected by the automatic device for extraction of exfoliated colonocytes from human feces were cancer cells. Conclusions As one of the latest-developed approaches, immunobead-based concentration of exfoliated colonocytes appears practical. An automatic device thereby developed may be used for early detection of colorectal cancers. 相似文献
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焦测序技术是一种基于生物发光法测定焦磷酸盐的测序技术,在进行DNA序列分析时不需要电泳和荧光标记,定量性能好,结果准确,可实现自动化。但其应用过程中存在3个技术瓶颈:一是测序试剂灵敏度低、成本高;二是测定仪器价格昂贵;三是测序模板制备过程繁琐。本课题组针对这些技术瓶颈,提出了一整套解决方案,包括高灵敏度焦测序反应试剂的研制、小型便携式焦测序仪的研制、测序模板的制备方法研究等。建立的高灵敏度微型化焦测序平台在分子诊断的各个领域得到了充分的应用,如细菌病毒转基因成分等的序列测定、单核苷酸多态性测定、拷贝数变异测定、基因突变位点测定、microRNA测定、基因表达量测定和药物基因组学研究,具有测序灵敏度高、仪器体积小、成本低、操作简便快速等优点,应用前景广阔。本文详细介绍了本课题组在提高焦磷酸测序反应灵敏度、简化测序过程、改进测序仪器和拓展焦磷酸测序应用范畴所做的系列创新性工作。 相似文献
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杂合型单核苷酸多态性定量焦测序测定法用于唐氏综合征快速诊断的探索 总被引:1,自引:0,他引:1
目的 通过筛查人21号染色体上的杂合型单核苷酸多态性(single nucleotide polymorphism,SNP)位点,初步建立基于定量焦磷酸测序反应的唐氏综合征分子诊断方法.方法 基于改进引物设计的等位基因特异性扩增法,在21号染色体上选取7个SNP位点进行杂合子筛选,通过焦测序法检测SNP中两个等位基因型的比值,并作为诊断唐氏综合征的依据.结果 通过对84名正常中国人基因组样本进行筛查,得到6个杂合率较高的SNP位点.6个SNP位点的杂合子覆盖率为92.9%.应用这6个SNP位点对10例唐氏综合征患者的样本进行了焦测序定量检测,结果表明10例患者样本中有9例样本的两个基因型比值为2:1或1:2,1例未检出杂合子,检出率为90%.结论 初步建立了一种唐氏综合征辅助诊断方法,具有成本低、操作简单、快速和结果明了的优点,可以有效地快速诊断唐氏综合征,为今后进一步完善该方法,并将其用于临床诊断奠定了基础. 相似文献
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