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71.
Diagnosis of Kala-Azar by Nested PCR Based on Amplification of the Leishmania Mini-Exon Gene 总被引:4,自引:0,他引:4 下载免费PDF全文
Ken Katakura Shin-Ichiro Kawazu Toshimitsu Naya Koichi Nagakura Mamoru Ito Masamichi Aikawa Jing-Qi Qu Li-Ren Guan Xin-Pin Zuo Jun-Jie Chai K.-P. Chang Yoshitsugu Matsumoto 《Journal of clinical microbiology》1998,36(8):2173-2177
To diagnose visceral leishmaniasis (kala-azar), we have developed a nested PCR method based on amplification of the mini-exon gene, which is unique and tandomly repeated in the Leishmania genome. Nested PCR was sufficiently sensitive for the detection of DNA in an amount equivalent to a single Leishmania parasite or less. We examined the usefulness of this PCR method using bone marrow aspirates and buffy coat cells collected from kala-azar patients who had or had not received chemotherapy in northwest China. We obtained PCR positivity for all of the parasitologically positive bone marrow samples from the patients. Some ambiguities with the primary PCR results were eliminated by the subsequent nested PCR. The buffy coat samples from 7 of 12 patients with splenomegaly were positive by the nested PCR, although only 2 of them were positive for parasites by culture. However, buffy coat samples from nine children, whose splenomegaly has been reduced and clinically cured by antimony treatment, were all negative. Thus, this nested PCR method represents a new tool for the diagnosis of kala-azar with patient blood samples instead of bone marrow or spleen aspirates obtained by more invasive procedures. 相似文献
72.
73.
胸腰脊神经根鞘形态观测及其临床意义 总被引:9,自引:1,他引:9
目的:为了探讨腰腿疼痛等疾病与脊神经根鞘的关系。方法:用巨视解剖和游标卡尺测量法对15具尸体的胸腰脊神经根鞘进行了解剖学观察与测量。结果:①左、右胸腰脊神经根鞘长度和横径基本对称;②T1根鞘长度和横径大于其它胸神经根鞘,接近L2水平,L3~L5根鞘长度和横径大于其它胸腰神经根鞘,尤其L5更为突出;③胸腰脊神经根鞘开口式,由上向下,由2~3孔逐渐减至1孔。结论:①T1、L2~L5脊神经根鞘既长又粗,与周围接触范围大,受损危险增大;②根鞘开口式孔数由上向下减少,发生在鞘内的炎症和肿瘤引起前、后根同时受累的机会增多。 相似文献
74.
Steffen Dietzel Anna Jauch Dirk Kienle Guoquiong Qu Heidi Holtgreve-Grez Roland Eils Christian Munkel Michael Bittner Paul S. Meltzer Jeffrey M. Trent Thomas Cremer 《Chromosome research》1998,6(1):25-33
Fluorescence in situ hybridization (FISH) with microdissection probes from human chromosomes 3 and 6 was applied to visualize arm and subregional band domains in human amniotic fluid cell nuclei. Confocal laser scanning microscopy and quantitative three-dimensional image analysis showed a pronounced variability of p- and q-arm domain arrangements and shapes. Apparent intermingling of neighbouring arm domains was limited to the domain surface. Three-dimensional distance measurements with pter and qter probes supported a high variability of chromosome territory folding. 相似文献
75.
P-gp、GSTπ及TopoⅡ在胃癌中的表达及临床意义 总被引:13,自引:0,他引:13
目的:探讨耐药基因蛋白P-gp、GSTл和TopoⅡ在胃癌中的表达及其临床意义。方法:应用S-P免疫组化法对85例胃癌进行检测。结果:胃癌组织P-gp、GSTл表达率分别为37.65%及63.53%,表达强度与临床分期有关,其中高分期者P-gp表达较低分期者为高。TopoⅡ表达率为55.29%,阳性率与组织学分类相关,分化较低者(59.57%)较分化较高者(38.30%)阳性率高。结论:P-gp、GSTл、TopoⅡ的耐药机制各不相同,根据P-gp、GSTл和TopoⅡ表达情况进行耐药物选择对办癌化疗具有重要的指导意义。 相似文献
76.
Molecular epidemiology of Vibrio cholerae O139 in China: polymorphism of ribotypes and CTX elements 总被引:5,自引:0,他引:5 下载免费PDF全文
Qu M Xu J Ding Y Wang R Liu P Kan B Qi G Liu Y Gao S 《Journal of clinical microbiology》2003,41(6):2306-2310
Vibrio cholerae O139, the second etiological serogroup of cholera, triggered the first outbreak of O139 cholera in China in 1993. To analyze the clone polymorphism of O139 isolates in China, 117 strains of V. cholerae O139, isolated from different areas in China between 1993 and 1999, were selected to characterize the phylogenetic relationships by molecular techniques. Analysis of restriction fragment length polymorphism in the conserved 16S rRNA gene revealed seven different ribotypes within the 117 strains. Among these strains, there were eight that lacked the cholera toxin gene (ctxAB), zot, and the repetitive sequence (RS); these eight strains belonged to three individual ribotypes. Our results suggested that V. cholerae O139 strains in China had clone diversity in phylogeny. The results of our hybridization patterns for CTX genetic elements (ctxAB, zot, and RS) showed that CTXPhi genomes in most V. cholerae O139 strains had two or more copies and had extensive restriction patterns even for the strains which belong to the same ribotype. For 22 (20.1%) strains, the copies of ctxAB were different from those of zot, suggesting that a ctxAB-negative CTXPhi genome may exist in O139 strains. This ctxAB-negative CTXPhi genome may coexist with the intact CTXPhi genome in a strain. In addition, the dendrogram for I-CeuI-generated pulsed-field gel electrophoresis patterns showed that V. cholerae serogroup O139 has a closer relationship with one strain of serogroup O22 than with the strains of serogroup O1. The results of this study showed the clonal diversity and the distribution of O139 strains in China, suggesting multiple origins of the O139 cholera epidemic or sporadic events. 相似文献
77.
Monosomy for the short arm of chromosome 18 is one of the most frequent autosomal deletions observed. While most cases result from terminal deletion of 18p, 16% of cases reported were as a result of an unbalanced whole arm translocation resulting in monosomy 18p. The origin and structure of these derivative chromosomes were reported in only a few cases. We report the prenatal diagnosis and characterization of a new case of monosomy 18p as a result of an unbalanced whole arm translocation. Amniocentesis was performed at 15 weeks of gestation on a 34-year-old woman initially referred for advanced maternal age. Holoprosencephaly was identified by ultrasound at the time of amniocentesis. Karyotype analysis showed an unbalanced whole arm translocation between the long arm of one chromosome 18 and the long arm of one chromosome 22, 45,XX,der(18;22)(q10;q10), in all metaphases. In effect, the fetus had monosomy for 18p. Parental karyotypes were normal, suggesting a de novo origin for the der(18;22). Fluorescence in situ hybridization (FISH) analysis was performed with alpha-satellite probes D18Z1 and D14Z1/D22Z1 to identify the origin of the centromere on the der(18;22). Signal was observed with both probes, indicating that the centromere was composed of alpha-satellite DNA from both constituent chromosomes. Genotyping of the fetus and her parents with chromosome 18p STS marker D18S391 showed only the paternal 187 bp allele was present in the fetus, indicating that it was the maternal chromosome 18 involved in the der(18;22). This case and previous reports show that de novo unbalanced whole arm translocations are more likely to retain alpha-satellite sequences from the two chromosomes involved. 相似文献
78.
树突状细胞负载肝癌抗原肽疫苗体外诱导特异性免疫学反应的研究 总被引:1,自引:1,他引:1
目的:研究树突状细胞(dendritic cell,DC)负载肝癌抗原肽EPVTKAEML体外诱导特异性CTL的能力及其抑癌效果。方法:用顺序特异引物聚合酶链反应技术(PCR—SSP)选择HLA—B7表型供者,从脾组织中分离、培养DC-EPVTKAEML特异性CTL。用^51Cr释放法检测CTL的杀伤活性,并用抗HLA-1分子单抗(mAb)进行杀伤抑制实验。结果:找到4例HLA-B7杂合子供者,用DC负载HLA-B7限制的抗原肽EPVTKAEML可诱导特异性CTL反应,对肝癌细胞HHCC有较强的杀伤作用。结论:DC负载抗原肽EPVTKAEML在体外可诱发较强的特异性免疫反应。 相似文献
79.
Qu CF Song EY Li Y Rizvi SM Raja C Smith R Morgenstern A Apostolidis C Allen BJ 《Clinical & experimental metastasis》2005,22(7):575-586
Purpose: The urokinase plasminogen activator (uPA) and its receptor (uPAR) are expressed by pancreatic cancer cells and can be targeted
by the plasminogen activator inhibitor type 2 (PAI2). We have labeled PAI2 with 213Bi to form the alpha conjugate (AC), and have studied its in vitro cytotoxicity and in vivo efficacy.
Methods and Materials: The expression of uPA/uPAR on pancreatic cell lines, human pancreatic cancer tissues, lymph node metastases, and mouse xenografts
were detected by immunohistochemistry, confocal microscopy, and flow cytometry. Cytotoxicity was assessed by the MTS and TUNEL
assay. At 2 days post-cancer cell subcutaneous inoculation, mice were injected with AC by local or systemic injection.
Results: uPA/uPAR is strongly expressed on pancreatic cancer cell lines and cancer tissues. The AC can target and kill cancer cells
in vitro in a concentration-dependent fashion. Some 90% of TUNEL positive cells were found after incubation with 1.2 MBq/ml of AC.
A single local injection of ~222 MBq/kg 2 days post-cell inoculation can completely inhibit tumor growth over 12 weeks, and
an intraperitoneal injection of 111 MBq/kg causes significant tumor growth delay.
Conclusions: 213Bi-PAI2 can specifically target pancreatic cancer cells in vitro and inhibit tumor growth in vivo. 213Bi-PAI2 may be a useful agent for the treatment of post-surgical pancreatic cancer patients with minimum residual disease. 相似文献
80.
黄皮酰胺促钾通道开放 总被引:1,自引:0,他引:1
一种新发现的具有促智作用的药物——黄皮酰胺能抑制去甲肾上腺素(NE)或KCl引起的血管平滑肌收缩。本研究旨在应用膜片钳(patch clamp)技术探讨黄皮酰胺对Wistar大鼠尾动脉平滑肌细胞膜钾离子通道的作用。单个平滑肌细胞用酶法分离,以细胞封接方式记录离子通道活动。在细胞池内注入2μM黄皮酰胺后,钾离子通道活动明显增强。用本实验室开发的计算机软件(patch clamp analysis system,Version 1.0)计算分析通道活动的特征参数。 相似文献