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1.
人端粒酶RNA的cDNA探针制备及其对胃粘膜细胞端粒酶RNA表达的检测 总被引:3,自引:0,他引:3
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
2.
Active production of anti-human T-lymphotropic virus type I (HTLV-I) IgM antibody in HTLV-I-associated myelopathy 总被引:2,自引:0,他引:2
Kunihiko Nagasato Tatsufumi Nakamura Ohishi Kiyosumi Kohji Shibayama Masakatsu Motomura Ichinose Katsuhiro Mitsuhiro Tsujihata Shigenobu Nagataki 《Journal of neuroimmunology》1991,32(2):105-109
We investigated the presence of anti-human T-lymphotropic virus type I (HTLV-I) IgM in sera and cerebrospinal fluid from patients with HTLV-I-associated myelopathy (HAM) by Western blot analysis. Analyses of 36 serum samples revealed that most patients (31/36; 86.1%) had anti-HTLV-I IgM, whereas only four of 23 (17.4%) HTLV-I carriers had it. In studies of cerebrospinal fluid, anti-HTLV-I IgM was detected in 24 of 36 (66.7%) HAM patients, whereas none was detected in nine HTLV-I carriers. The differences were statistically significant (p less than 0.01). These results suggest that persistent active replication of HTLV-I occurs in the central nervous system as well as in the peripheral blood of HAM patients, and may contribute to the development of HAM. 相似文献
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中重型β地中海贫血基因类型分析 总被引:1,自引:0,他引:1
目的 了解中间型和重型β地中海贫血基因突变类型及其相关血液,生化变化。方法 应用反向点杂交法检测16种β地贫点突变基因,常规进行血细胞分析及其他地贫筛查试验。结果 27例中重型β地贫患者中10例为纯合子,17例为双重杂合子,10例纯合子中5例CD41-42纯合子,占50%,3例TATAnt-28纯合子,占30%;CD17纯合子和IVS-nt654纯合子各1例,各占10%,17例双重杂合子中5例为IVS-nt654/CD41-42占29.4%,3例为CD17/CD41-42,占17.6%;3例为TATAnt-28/CD41-42,占17.6%;2例为βE/IVS-nt654,占11.6%;CD17/TATAnt-28,IVS-nt654/CD17,IVS-nt654/CD1-1,1CD71-72/IVS-nt654各1例,各占5.9%。27例患者血红蛋白均低于90.0g/L。平均为58.8g/L;平均MCV为65.0fl。脆性均少于60%。结论 中重型β地中海贫血基因突变类型多样,组合类型不同,临床表现轻重不一,多呈中重度贫血,血液,生化均有明显改变,多需输血维持生命,故应做好产前诊断,预防其出生。 相似文献
6.
妇科疾病中人乳头瘤病毒感染的分子流行病学调查 总被引:1,自引:0,他引:1
目的:探讨各种妇科疾病与人乳头瘤病毒感染的关系,建立不同妇科疾病和不同年龄段妇女人乳头瘤病毒感染的流行病学资料库。方法:应用反向点杂交技术分别对疾病组1 512例病人标本和正常组500例标本进行HPV检测,所得数据用SPSS 13.0软件包进行统计分析。结果:正常组500例标本中,阳性标本101例,感染率为20.2%,疾病组1 512例标本中,阳性标本523例,感染率为34.6%,其中双重感染82例,占阳性标本的15.7%,多重感染34例,占阳性标本的6.5%,而高危感染340例,感染率为22.5%,占阳性标本的65.0%,其中单纯HPV16亚型感染155例,占所有阳性标本的29.6%;不同年龄段、不同性生活史、不同妇科疾病以及不同首次性生活年龄的HPV感染检出率都有显著性差异。结论:正常组和疾病组的HPV感染率有显著性差异(2χ=36.37,P<0.01)。在HPV感染的普查中可以有重点的选择高危人群,这样更加有针对性,从而大大降低普查成本。 相似文献
7.
Marina Quartu Maria Pina Serra Annalisa Manca Paolo Follesa Rossano Ambu Marina Del Fiacco 《International journal of developmental neuroscience》2003,21(6):309-320
The immunohistochemical occurrence of the high affinity neurotrophin (NT) receptors trkA, trkB, and trkC is shown in the pre-term newborn, infant, and adult human post-mortem cerebellum. Immunoreactive neuronal perikarya and processes were observed in all specimens examined, where they appeared unevenly distributed in the cerebellar cortical layers and deep nuclei, and showed regional differences among cerebellar lobules and folia. The trk receptor-antibodies, tested by Western blot on human cerebellum homogenates, revealed multiple immunoreactive bands for trkA and single bands for trkB and trkC. The results obtained show the tissue localization of the trk receptor-like immunoreactivity in the human cerebellum from prenatal to adult age. The analysis for codistribution of the receptors with the relevant ligand and among the receptors in discrete cortical and deep nuclei tissue fields shows a wide variety of conditions, from a good similarity in terms of type and density of labeled structures, to a lack of correspondence, and suggests the possibility of colocalization of trk receptors with the relevant neurotrophin and among them in the cerebellar cortex. These results sustain the concept that the neurotrophin trophic system participates in the development, differentiation, and maintenance of the human cerebellar connectivity and support the possibility of a multifactorial trophic support for the neurotrophins through target-derived and local mechanisms. 相似文献
8.
Nucleic acid spot hybridization with nonradioactive labeled probes in screening for human papillomavirus DNA sequences 总被引:1,自引:0,他引:1
We examined 161 human tissue samples using the spot hybridization technique with nonradioactive labeled DNA probes of human papillomavirus (HPV). Whole cells were spotted on nitrocellulose filters; DNA of the cells was denatured and fixed to the filter. Then the DNA spots were hybridized to nonradioactive labeled DNA and monitored by a sandwich immunoenzymatic reaction. This technique is simple, sensitive, specific, requires no special equipment, and can be used in clinical settings. HPV DNA was found in 92% of samples in which, on the basis of histologic and colposcopic criteria, its presence was suspected, as well as in 31 samples where it was not suspected. 相似文献
9.
C.L. Richardson W.P. Tate S.E. Mason P.A. Lawlor M. Dragunow W.C. Abraham 《Brain research》1992,580(1-2):147-154
Expression of the immediate early gene zif/268 (also termed NGFI-A, Krox 24, TIS8 and Egr-1) was investigated in awake rats following various long-term potentiation (LTP) induction protocols.zif/268 mRNA (Northern blots) and protein (immunohistochemistry) levels sharply increased following LTP, and followed a time course characteristic of other immediate early genes. When measured across 3 tetanization protocols known to produce differing degrees of LTP persistence,zif/268 induction was found to be more highly correlated with LTP duration than with the magnitude of initial LTP. These data support the hypothesis that the immediate early gene zif/268 plays a role as a third messenger in the cascade of cellular and nuclear events that govern the persistence of LTP. 相似文献
10.
链置换式扩增检测羊水中巨细胞病毒DNA 总被引:2,自引:1,他引:1
目的:介绍一种简便快速准确检测羊水中CMV-DNA的改良PCR-链置换式扩增用于诊断胎儿先天感染CMV。方法,将组成套式PCR的外内两对引物按照一定比例(外:内=1:50-100)加在同一试管中一次扩增羊水和胎儿组织中CMV-DNA。结果:90例异常孕产史的孕妇羊水检测CMV-DNA,阳性率为38.9%(35/90),其中合并染色数目异常2例(47,XYY和47,XX,+21)(已引产)核型及染色 相似文献