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71.
用Amp-FLP方法分析江浙沪汉族人群DIS80位点多态性   总被引:10,自引:0,他引:10  
采用PCR结合PAGE电泳及银染技术,即Amp-FLP方法,分析了148名江浙沪汉族人中D1S80位点的多态性分布,观察到20种等位基因,53种基因型。首次在国际上发现重复单元数为39的等位基因。该位点观察杂合性为0.86,个体鉴别力为0.96,多态性信息含量为0.83,基因频率分布符合Hardy-Weinb erg法则。本文结果提示,采用Amp-FLP技术分析D1S80位点多态性,样本分型具有较高的准确性及灵敏度,适用于人类民族演变、法医学个体指认、亲子鉴定、遗传病基因连锁分析等研究领域。  相似文献   
72.
p28, a 28kD protein from toad (Bufo bufo gargarizans) oocytes, was identified by using p13sucl-agarose affinity chromatography. Sequence homology analysis of the full-length cDNA of p28 (Gene Bank accession number: AF 314091) indicated that it encodes a protein containing 224 amino-acids with about 55% identities and more than 70% positives to human, rat or mouse UCH-L1, and contains homological functional domains of UCH family. Anti-p28 monoclonal antibody, on injecting into the oocytes, could inhibit the progesterone-induced resumption of meiotic division in a dose-dependent manner. The recombinant protein p28 showed similar SDS/PAGE behaviors to the native one, and promoted ubiquitin ethyl ester hydrolysis, a classical catalytic reaction for ubiquitin carboxyl terminal hydrolases (UCHs). The results in this paper reveal that a novel protein, p28, exists in the toad oocytes, is a UCH L1 homolog, was engaged in the process of progesterone-induced oocyte maturation possibly through an involvement in prot  相似文献   
73.
Previous studies have indicated that noggin exerts its neural inducing effect by binding andantagonizing bone morphogenetic protein 4(BMP4).In order to further clarify the relationship between thestructure and the function of noggin,and elucidate the possible mechanism responsible for noggin-BMP4interaction,we generated three noggin mutants,C168S,C174S and C197S,by using a site-directed mu-tagenesis method.Ectopic expression of wild-type(WT)noggin,C174S or C197S,in Xenopus animal caps(ACs)by mRNA injection converted the explants(prospective ectoderm)into neural tissue,as indicated bythe neural-like morphology and expression of the neural cell adhesion molecule(NCAM)in the ACs.Incontrast,ACs expressing C 168S suffered an epidermal fate similar to the control caps.Similarly,among the threemutants,only C 168S lost the dorsalizing function.These studies highlight the critical role played by Cys168in noggin's biological activities.It probably participates in the formation of an intermolecular disulfide bridge.  相似文献   
74.
利用多重PCR和四色荧光(5-FAM,JOE,NED和ROX)自动化检测技术调查上海地区汉族人群D3S1358、vWA、FGA、D8S1179、 D21S11、 D18S51、D5S818、D13S317、D7S820等9个STR基因座多态性分布并计算该9个基因座的基因频率(Pi)、个体鉴别力(DP)、无偏倚期望杂合性(H)、多态性信息含量(PIC)和非父排除概率(PE)。结果显示:9个STR基因座的基因型分布符合Hardy-Weinberg平衡,9个STR基因座中FGA基因座的DP值最高为0.9584,D8S1179的H值最高为0.9403,D18S51的PIC值最高为0.8560,D18S51的PE值最高为0.7391,9个STR基因座累积个体鉴别力(CDP)为0.9999996,累积非父排除能力(CPE)为0.99991。9个STR基因座适合作为中国人群的遗传标志,用于人类学、遗传疾病基因连锁分析、法医学亲子鉴定和个体识别等研究领域。 Abstract:By multiplex amplification and four fluorescent technique,the polymorphism distributions of nine STR loci,D3S1358,vWA,FGA,D8S1179,D21S11,D18S51,D5S818,D13S317 and D7S820 were investigated in Shanghai Han population.Gene frequency (Pi),power of discrimination (DP),polymorphism information content (PIC) expected heterozygosity (H) and probability of paternity exclusion (PE) were calculated.All loci meet Hardy-Weinberg equilibrium.DP of FGA locus,H of D8S1179 locus,PIC of D18S51 locus and PE of D18S51 locus are the biggest among nine STR loci.Cumulate DP (CDP) of nine STR loci is 0.9999996,Cumulate PE (CPE) of nine STR loci is 0.99991.Nine STR loci could be used as the genetic markers of Chinese population in the studies of anthropology,linkage analysis of genetic disease genes,individual identification and paternity test in forensic medicine.  相似文献   
75.
本文首次较为完整地报道了藏汉通婚子代群体的14项肤纹参数(其中藏父汉思及汉父藏母各100 例),并将这些肤纹参数分别与其藏汉父母样本的有关肤纹参数进行比较,再与1000例藏族及1040例 汉族两个大样本的有关肤纹参数进行比较。结果表明:藏汉后代的肤纹特征介于藏族和汉族之间,提示 肤纹参数的多因子遗传本质。  相似文献   
76.
Citrus tristeza virus(CTV) is one of the most economically important citrus viruses and harms the citrus industry worldwide.To develop reliable and effective serological detection assays of CTV,the major capsid protein(CP) gene of CTV was expressed in Escherichia coli BL21(DE3) using the expression vector p ET-28 a and purified through Ni~+-NTA affinity chromatography.The recombinant protein was used to immunize BALB/c mice.Four hybridoma cell lines(14B10,14H11,20D5,and20G12) secreting monoclonal antibodies(MAbs) against CTV were obtained through conventional hybridoma technology.The titers of MAb-containing ascitic fluids secreted by the four hybridoma lines ranged from 10-6 to 10-7 in indirect enzyme-linked immunosorbent assay(ELISA).Western blots showed that all four MAbs could specifically react with CTV CP.Using the prepared MAbs,dot-ELISA,Tissue print-ELISA,and triple antibody sandwich(TAS)-ELISA were developed to detect CTV in tree nurseries and epidemiological studies.The developed dot-ELISA and TAS-ELISA methods could detect CTV in crude extracts of infected citrus leaves with dilutions of 1:2560 and1:10,240(w/v,g/m L),respectively.Tissue print-ELISA was particularly useful for large-scale field sample detection,mainly owing to its simplicity and lack of sample preparation requirements.The field survey revealed that CTV is prevalent on citrus trees in the Chongqing Municipality,Jiangxi Province,and Zhejiang Province of China.The coincidence rate of serological and RT-PCR test results reached more than 99.5%.The prepared MAbs against CTV and established sensitive and specific serological assays have a significant role in the detection and prevention and control of CTV in our country.  相似文献   
77.
Type 1 diabetes mellitus is an autoimmune disease caused by T cell-mediated destruction of pancreatic beta islets. With its incidence continuous rising in the pediatric age group in recent years, it is becoming a serious threat to the human health. Up to now, there has been no effective therapy for diabetes mellitus, and islet transplantation still remains a promising ap-proach to the treatment of Type 1 diabetes. However, two serious problems hinder the successful islets transplantation, tha…  相似文献   
78.
Jiang M  Zhao X  Han W  Bian C  Li X  Wang G  Ao Y  Li Y  Yi D  Zhe Y  Lo WH  Zhang X  Li J 《Human genetics》2006,120(2):238-242
Distal arthrogryposis (DA) is composed of a group of clinically and genetically heterogeneous disorders, characterized by multiple congenital contractures of the limbs. Point mutations in three genes encoding contractile fast-twitch myofibers, TPM2, TNNI2 and TNNT3, were recently identified in DA type 1 (DA1; MIM 108120) and DA type 2B (DA2B; MIM 601680). We have described a large Chinese DA family in which different individuals had phenotypes similar to DA1 or DA2B. To map the disease locus in this family, two-point linkage analysis was first performed using microsatellite markers selected from the genomic regions close to the TPM2, TNNI2/TNNT3 and TNNC2 genes. A positive LOD score of 3.61 at θ = 0 was obtained with the marker close to the TNNI2/TNNT3 genes, corresponding to the genetic mapping site of DA2B. Direct sequencing of the PCR-amplified DNA fragment spanning exon 8 of the TNNI2 gene showed a heterozygous deletion, c.523_525delAAG (p.K175del), in the proband. This novel mutation was confirmed to cosegregate with the DA phenotype in affected individuals but not detected in all unaffected individuals of the family and not in 50 healthy controls. In summary, we have found a novel TNNI2 mutation in a Chinese family with DA2B. Our work represents the first report on the link between TNNI2 and the DA phenotype in Chinese.Miao Jiang and Xiuli Zhao contributed equally to the work  相似文献   
79.
80.
Superficial fungi are the etiologic pathogens of various dermatophytoses, such as tinea capitis, tinea corporis, tinea inguinalis, tinea manus, tinea unguium and tinea pedis. These widespread infections affect up to 25% of the worlds population, a percentage that has continued to increase in recent years. T. rubrum is the most common superficial fungus, accounting for at least 60% of all infections of this type. T. rubrum can induce dermatophytoses in different parts of the hu-man skin, and ca…  相似文献   
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