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排序方式: 共有3212条查询结果,搜索用时 15 毫秒
1.
目的 建立人端粒酶RNA表达的检测方法。方法 制备人端粒酶RNA,(human telomeraseRNA,hTR)的cDNA探针,分别应用RNA斑点杂交与端粒重复序列扩增法(TRAP)分析检测不同胃粘膜的端粒酶RNA的表达与端粒酶活性。结果 人端粒酶RNA的cDNA探针制备成功。18例活检胃癌组织及45例手术胃癌组织RNA斑点杂交检测的阳性率均为l00%,相应TRAP分析的阳性率分别为88.89%、86.67%,低于RNA斑点杂交(P<0.05)。同时RNA斑点杂交结果提示在非癌胃组织中随着肠化程度增高人端粒酶RNA表达也增强。结论 RNA斑点杂交检测人端粒酶RNA,具有高度的敏感性和特异性,弥补了TRAP分析敏感性不足的缺点。  相似文献   
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目的:研究中国汉族群体中α艾杜糖苷酶基因D4S111位点的遗传多态性。方法:采用扩增片段长度多态性(AmpFLP)分析技术,检测了广州地区汉族无血缘关系健康个体97名。结果:D4S111位点,在97名无关个体中发现5个等位基因和9种基因型,等位基因片段长度为830~510bp,基因频率为00052~03608,PIC为05966,杂合性为078。结论:中国汉族群体中D4S111位点具有高度多态性,并与其它种族间存在差异性。  相似文献   
4.
致倦库蚊有机磷抗性相关扩增酯酶B基因的多样性   总被引:5,自引:0,他引:5  
本实验从佛山和成都两地的致倦库蚊群体中筛选出3个酯酶类型不同的有机磷(OP)抗性品系,FS-1、FS-2和CD-1品系。各品系的酯酶基因B扩增水平、酯酶活性和OP抗性水平三者一致。各品系酯酶B基因限制性酶切片段比较分析表明,我国的OP抗生库蚊群体中不仅有世界性分布的酯酶B1和B2,而且在佛山和成都地区各有一个新的独立扩增的酯酶B,分别命名为B6和B7。  相似文献   
5.
Gene amplification occurs frequently in tumour tissues yet is,in general, non-inheritable. To study the molecular mechanismsconferring this restraint, we created transgenic mice carryinga human butyrylcholinesterase (BCHE) coding sequence, previouslyfound to be amplified in a father and son. Blot hybridizationof tail DNA samples revealed somatic transgene amplificationswith variable restriction patterns and intensities, suggestingthe occurrence of independent amplification events, in 31% (11/35)of mice from the FII generation but in only 3.5% (2/58) of theFII and FIV generations. In contrast, >10-fold amplificationsof the BCHE transgene and the endogenous acetylcholinesteraseand c-raf genes appeared in both testis and epididymis DNA from>80% of FIII mice. Drastic, selective reductions in testisBCHEmRNA but not in actin mRNA were detected by the PCR amplificationof testis cDNA from the transgenic mice, and apparently resultedin the limited transmission of amplified genes. The testicularamplification of the BCHE transgene may potentially representa general phenomenon with clinical implications in human infertility.  相似文献   
6.
应用对应于Dystrophin基因缺失热区的二对PCR引物和一对内对照无关引物,在同一反应体系中扩增,检测66例DMD/BMD患者。发现其中25例存在17号或49号外显子缺失,与同时采用cDNA探针杂交检测出的35例基因缺失相比.检出率达71.4%。说明该扩增系统能够作为快速筛查缺失型DMD/BMD患者的有效手段。这对指导合理选用探针,尤其在产前诊断方面,具有重要意义。  相似文献   
7.
In this study, we evaluated the presence of human papillomavirus (HPV) DNA in organs of the female upper genital tract, using nine hysterectomy and salpingo-oophorectomy specimens affected by HPV-positive invasive cervical carcinomas, to establish if cervical HPV infection can spread to upper tracts of the female genital system. HPV DNA was evaluated by polymerase chain reaction (PCR) in all cervical carcinomas as well as in all tracts of the genital system. Then, these data were compared with the results obtained from PCR study of five other hysterectomy and salpingo-oophorectomy specimens (control cases). The criteria used for selection of the control cases were informed consent of the patients for research at the time of surgery, absence of neoplasms, absence of any anatomic lesion caused by HPV in cervix, and external genitalia. All selected cases were squamous cervical carcinomas. PCR analysis revealed HPV DNA in all cases of cervical carcinoma. The HPV DNA was detected as weak positivity on PCR analysis in other organs of the genital system. However, the distribution of HPV DNA varied in the various cases and in the different tracts of the same hysterectomy and salpingo-oophorectomy specimen. We believe that the HPV DNA, detected as a weakly positive signal, in the upper genital tract of patients who have a cervical squamous carcinoma could be a reflection of a latent HPV infection, as well as a sign of the existence of micrometastases containing HPV DNA, which cannot be detected by conventional histologic techniques.  相似文献   
8.
Summary Tumor DNA from 27 patients with treated or untreated transitional cell carcinomas of the urinary tract was screened for genomic alterations of the multidrug resistance genes in order to determine whether structural changes of these genes are important in primary urothelial tumors. None of the tumors showed evidence of amplification or rearrangements of either mdr1 or mdr2. The lack of amplification or rearrangements observed in these tumors suggests that structural alterations of the mdr1 and mdr2 genes are not important mediators of drug resistance in TCC.Supported in part by grant CA-34775 from the National Institutes of Health and by a grant from the Heckscher Foundation for ChildrenDr. Klein is a fellow of the American Cancer Society  相似文献   
9.
日本血吸虫亲免素基因的扩增及序列分析   总被引:2,自引:0,他引:2  
[目的]研究日本血吸虫亲免素基因编码序列的结构及进行初步的功能预测.[方法]用5'端和3'端锚定PCR从尾蚴文库中扩增,以获取日本血吸虫中国大陆株亲免素基因完整的开放阅读框(open readingframe,ORF);用生物信息学技术确认其是否为亲免素编码基因并进行结构功能的初步分析和预测.[结果]用5'端和3'端锚定PCR从尾蚴文库中获得了亲免素基因5'端和3'端所缺序列,得到的亲免素基因cDNA的总序列长为1 438 bp,其ORF长1 296 bp,编码431个氨基酸.利用生物信息学技术鉴定其为日本血吸虫亲免素基因的完整cDNA序列.并用RT-PCR从日本血吸虫尾蚴mRNA扩增出亲免素基因的ORF.[结论]成功获得了日本血吸虫亲免素编码基因的全长cDNA,为进一步的功能研究打下了基础.  相似文献   
10.

Background

Since its sudden appearance and link to microcephaly in 2015, the number of PubMed references for Zika virus (ZIKV) has risen from 181 to 5163, at time of writing, with a vast proportion focused on the consequences of ZIKV infection during pregnancy. This level of attention underlies increased demand for sensitive and specific diagnostic tools able to assess risk to an unborn child, as well as to understand the dynamics and consequences of viral persistence.

Aim

Review the expanding knowledge on ZIKV persistence and diagnostic challenges and summarize current advancements in detection.

Sources

Peer-reviewed articles based on the search terms ‘Zika’ and ‘ZIKV’ combined with the terms ‘diagnostics’ ‘point-of-care diagnostics’ ‘viral load’ ‘persistence’ ‘detection’ ‘treatment’ ‘nucleic acid amplification testing’ ‘microsphere’ ‘PVRT’ ‘RVNT’ ‘RT-LAMP’ ‘NASBA’ SIBA’ ‘RPA’ ‘SHERLOCK’ ‘ELISA’, and ‘TMA’ as well as laboratory experience of the authors.

Content

Topics covered include the emergence of the ZIKV epidemic, pathogenesis of ZIKV infection, the nature of ZIKV persistence, complications in serological diagnosis, tried and novel diagnostic laboratory techniques, and a recent accounting of point-of-care testing (POCT) methods.

Implications

Surveillance and research in the case of ZIKV has shifted into a more rapid and coordinated worldwide directive than has occurred with most viral epidemics to date. The particular concentration of outbreaks in resource-limited settings increases the need for simple assays capable of reliable, inexpensive, high-throughput ZIKV diagnosis. This review serves to both catalogue current diagnostic options and consider their suitability at point-of-care.  相似文献   
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