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41.
探讨keratin 13基因在喉癌发生中的作用。方法在keratin 13基因内部及附近选择5个微卫星引物进行LOH分析,于DNA水平间接检测100例喉癌患者中该基因的缺失情况。结果5个STR位点均存在LOH,其中D17S1964E、D17S2092、D17S791、D17S1665及D17S808位点的LOH频率分别为30.48%、26.02%、21.62%、37.66%和21.51%,以D17S1665位点的LOH频率最高,杂合性丢失与临床分期无显著相关。结论Keratin13基因在喉癌的发生中具有重要作用,具体机制有待进一步研究。 相似文献
42.
目的 :探讨宫颈癌细胞中凋亡相关蛋白激酶 1(DAPK1 )基因CpG岛甲基化及其表达与宫颈癌的相关性 .方法 :应用甲基化特异性PCR和SABC免疫组化方法 ,检测 32(鳞癌 1 8,腺癌 1 4 )例宫颈癌组织DAPK1基因CpG岛甲基化修饰及蛋白表达 .结果 :宫颈癌中DAPK1基因甲基化扩增阳性率明显增高 5 6 .3% ,与正常宫颈比较有显著性差异 (P <0 .0 5 ) ,鳞癌与腺癌甲基化扩增阳性率无显著差异 (P >0 .0 5 ) ;宫颈癌中DAPK1蛋白表达阳性率降低 1 5 .6 3% ,与正常宫颈比较有显著性差异 (P <0 .0 5 ) ,鳞癌和 7例与腺癌无显著性差异 (P >0 .0 5 ) .结论 :DAPK1基因CpG岛异常甲基化修饰能抑制DAPK1的转录 ,使DAPK1蛋白不表达 ,丧失抑癌作用 ,是促进正常宫颈上皮细胞癌变的一个重要因素 相似文献
43.
论“恐伤”心理的基因定势表达 总被引:3,自引:0,他引:3
本文在基因定势表达研究概况基础上,列举0MIM上部分与恐惧等心理因素定势的基因与疾病,进而探讨心理、基因定势表达与精神病的关系。 相似文献
44.
目的 近年来产生了一些用于分析基因表达数据的聚类算法,却很少有关于评价聚类算法方法的研究。本研究的目的是尝试建立一个定量的评价基因表达数据聚类结果的方法。方法 本研究提供了一个系统的评价聚类结果的方法,利用我们提出的实验均方误差F值对几个常见的聚类算法进行比较。结果 利用F值对类质量的评价和利用已有的生物学知识对类进行分析的结果一致。结论 实验均方误差F值可以定量地评判用于基因表达数据的聚类算法。 相似文献
45.
用同位32~P标记乳酸脱氢酶-C(LDH-C)cDNA作为探针,与小鼠胸腺、脑、胰、心肌、骨骼肌、睾丸、肾、肺、肝的RNA以及人胰、皋丸、肝、骨骼肌、心肌及脑的RNA分别作点溃杂交(dot blot hybridization)及Northern印迹杂交,证实LDH-C基因只在睾丸中特异性表达。 相似文献
46.
The normally expressed κ immunoglobulin light chain gene repertoire and somatic mutations studied by single-sided specific polymerase chain reaction (PCR); frequent occurrence of features often assigned to autoimmunity 下载免费PDF全文
L JUUL L HOUGS V ANDERSEN A SVEJGAARD T BARINGTON 《Clinical and experimental immunology》1997,109(1):194-203
The expressed human κ light chain gene repertoire utilized by healthy individuals was studied by two different single-sided specific PCR techniques to avoid bias for certain V genes. A total of 103 rearranged κ sequences from peripheral blood mononuclear cells from healthy individuals were cloned from cDNA and assigned to the Vκ and Jκ germ-line genes with the closest overall homology. The use of cDNA rather than genomic DNA focused the analysis on activated B cells rich in mRNA. Accordingly, the sequences represented the applied repertoire and almost all were somatically mutated. V genes from the Jκ-proximal duplication unit of the κ locus were almost exclusively used. A total of 65% of the sequences could be assigned to four or five genes: A27 (humkv325), L6 (Vg), L2 (humkv328), and A3 and/or A19. N additions and P nucleotides were quite common and found in 32% and 21% of the sequences, respectively. Extended CDR3s more than nine residues in length were found in 18% of the sequences, and in 71% of cases this was due to insertion of an extra proline residue. This proline was usually explained from the germ-line sequences involved. These results are in good agreement with those of previous repertoire studies using potentially V-gene-biased techniques. Thus, it is clear that restricted V-gene usage, common N and P additions, and extended CDR3 regions are normal features and not, as has been claimed, characteristics of pathological autoantibodies. 相似文献
47.
The effect of sodium lauryl sulphate (SLS) on cytokeratin (CK) gene expression in hamster cheek pouch epithelium was studied with a hybridohistochemical technique. Using specific human anti-sense RNA probes, the plausible hamster mRNA counterparts for these human CK mRNAs were localized by detection of heterologous hybrids. In comparison with normal epithelium, the expression and distribution pattern of CK mRNAs in the hamster cheek pouch were obviously changed after application of SLS. There was a decreased expression of CK mRNAs in the hyperplastic basal layer, and increased expression in the hypertrophic granular layer. Strikingly, hybridization with the human CK 18 cRNA probe revealed an additionally expressed CK mRNA in the SLS-treated epithelium that was not found in the untreated epithelium. The present study indicates that cRNA probes for human CK mRNAs can be used successfully, not only to distinguish between different hamster CK mRNAs but also to investigate changes in CK gene expression upon the induction of non-neoplastic and neoplastic alterations in the hamster cheek pouch model. This may help elucidate the molecular changes involved in epithelial pathologies. 相似文献
48.
49.
SRY基因诊断在临床中的应用 总被引:1,自引:0,他引:1
应用聚合酶链式反应(PCR)扩增技术,对10例染色体核型为46,XY和1例为46,XX/46,XY的性反转、睾丸女性化、两性畸形及男性生殖器发育不良的患者进行了性别决定区(SRY)基因检测。结果表明9例46,XY和1例46,XX/46,XY患者的SRY基因存在,1例46,XY女性患者的SRY基因缺失。该结果表明能够用分子生物学技术对性反转、性发育异常的病因进行分析 相似文献
50.
Central nervous system (CNS) progenitor cells transiently proliferate in the embryonic neural tube and give rise to neurons and glial cells. A characteristic feature of the CNS progenitor cells is expression of the intermediate filament nestin and it was previously shown that the rat nestin second intron functions as an enhancer, directing gene expression to CNS progenitor cells. In this report we characterize the nestin enhancer in further detail. Cloning and sequence analysis of the rat and human nestin second introns revealed local domains of high sequence similarity in the 3' portion of the introns. Transgenic mice were generated with the most conserved 714 bp in the 3' portion of the intron, or with the complete, 1852 bp, human second intron, coupled to the reporter gene lacZ. The two constructs gave a very similar nestin-like expression pattern, indicating that the important control elements reside in the 714 bp element. Expression was observed starting in embryonic day (E)7.5 neural plate, and at E10.5 CNS progenitor cells throughout the neural tube expressed lacZ. At E12.5, lacZ expression was more restricted and confined to proliferating regions in the neural tube. An interesting difference, compared to the rat nestin second intron, was that the human intron at E10.5 mediated lacZ expression also in early migrating neural crest cells, which is a site of endogenous nestin expression. In conclusion, these data show that a relatively short, evolutionarily conserved region is sufficient to control gene expression in CNS progenitor cells, but that the same region differs between rodents and primates in its capacity to control expression in neural crest cells. 相似文献