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91.
用人Ⅳ型胶原蛋白免疫BALB/c小鼠,克隆了一组分泌抗人Ⅳ型胶原蛋白的杂交瘤细胞株,并且对其中的A2、A4、A5、B3和E2进行了鉴定。其抗体亚类分别为IgG1、IgG2、IgG2b、IgG2和IgG1。其亲和力常数Kaff=6.6×108M(-1)~6.0×10(10)M(-1)。它们均能特异性地识别人Ⅳ型胶原蛋白。  相似文献   
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目的:探索获取胎儿细胞DNA用于产前基因诊断的可行性,及能否用于预期胎儿性别。方法:收集92例孕早期人工流产妇女宫颈分泌物和绒毛组织,提取宫颈分泌物中DNA,扩增Y染色体特异重复序列DNA。短期培养制备绒毛染色体,分析核型确定流产胎儿性别。结果:92例经绒毛染色体核型分析的人工流产胎儿中,正确预期胎儿性别72例,准确率78%。结论:采集孕早期宫颈分泌物,可获得胎儿滋养层细胞DNA用于产前诊断,其准确性和可靠性有待进一步提高。  相似文献   
95.
建立了心肌细胞膜离子通道钠电流,钾电流和钙电流的动力数学模型,探讨了离子通道动力学机制,为进一步整合各离子电流数学模型用以研究动作电位全过程和为动物实验以及临床研究提供理论基础。  相似文献   
96.
Qin W  Gao J  Xing Q  Yang J  Qian X  Li X  Guo Z  Chen H  Wang L  Huang X  Gu N  Feng G  He L 《Neuroscience letters》2005,375(3):207-210
Recently, proteolipid protein 1 (PLP1) has been identified as downregulated in schizophrenia by quantitative PCR and other technologies. In this work we attempted to investigate the role of PLP1 in the etiology of schizophrenia using a family based association study in 487 Chinese Han family trios. The TDT for allelic association demonstrated that, in male, a weak association was detected in SNP rs475827 with p=0.0294, suggesting that the genetic polymorphisms within PLP1 in male are likely to confer an increased susceptibility to schizophrenia in the Chinese population.  相似文献   
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AIMS: To develop an alternative assay for specific genotyping of the -alpha(4.2) thalassaemia deletion based on the DNA sequence features surrounding the breakpoint. METHODS: The 5' and 3' ends of the breakpoint regions of the -alpha(4.2) allele and the normal homologous segments were sequenced in Chinese individuals. A sequence haplotype composed of four single nucleotide variations within the X2/X1 box of the -alpha(4.2) breakpoint region was found in all of the 10 Chinese -alpha(4.2) thalassaemia alleles studied. Based on these findings, a novel polymerase chain reaction (PCR)/denaturing high performance liquid chromatography (DHPLC) assay was developed for rapid genotyping of the -alpha(4.2) allele instead of traditional Southern blotting or Gap-PCR. This method involves amplification of the alpha globin target sequence encompassing these four polymorphic sites, followed by a partially denaturing HPLC analysis using the transgenomic WAVE DNA fragment analysis system. RESULTS: The three major genotypes (-alpha4.2/alphaalpha, -alpha(4.2)/--SEA, and alphaalpha/alphaalpha) could be distinguished through the characteristic chromatograms generated by the WAVE system. The accuracy of this technique was evaluated blindly, and the results were 100% (40 of 40) concordant with the genotypes previously characterised by Southern blotting or Gap-PCR. CONCLUSIONS: This study validates the PCR/DHPLC approach as a simple, rapid, highly accurate, and cost effective method, potentially adaptable for use in epidemiological surveys, genetic screening, and diagnosis of silent alpha+ thalassaemia and Hb H disease.  相似文献   
99.
We report a case of papillary carcinoma arising in a thyroglossal duct cyst, presenting with an anterior neck mass of a 31-year-old woman. The tumor was judged to be a primary lesion on the basis of intraoperative examination of the thyroid and pathologic findings of the mass. One year later, a small nodular mass in the left thyroid gland and lymph node enlargement of the right cervical lymph node were noted by follow-up imaging studies. Total thyroidectomy, right modified radical neck dissection and central neck dissection were performed. The thyroid gland revealed nodular hyperplasia without evidence of malignancy. On the other hand, the dissected neck lymph nodes revealed metastatic papillary carcinoma. Taken together, these findings suggested the tumor was a primary papillary carcinoma arising in the thyroglossal duct cyst.  相似文献   
100.
Plasmodium sporozoites develop in oocysts on the midgut wall of the mosquito and are released into the hemocoel. Approximately 15-20% of oocyst sporozoites will successfully attach to and invade salivary glands, their target organ. We have previously shown that the major surface protein of sporozoites, the circumsporozoite (CS) protein, binds specifically to salivary glands and not to other mosquito organs exposed to circulating hemolymph. In addition, a peptide from the N-terminal portion of CS protein inhibits binding of the protein to the glands. In this study, we have extended these findings and show that both the protein and the peptide can inhibit sporozoite invasion of salivary glands.  相似文献   
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