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991.
目的:研究黄体激素释放激素(Luteinizinghormone releasinghormone,LHRH)在大鼠体内的药动学规律。方法:用氯胺T法将125I标记到LHRH分子上(放化纯度96.2%),14只SD大鼠随机分为大剂量、小剂量组,每组7只,分别肌肉注射125I LHRH(小剂量组0.5mg.kg,大剂量组1.00mg.kg),给药后在21个不同时间点逐一取各鼠尾动脉血做放射性测定。结果:大鼠试验结果显示,大剂量组t1/2平均为67.83±20.84h;小剂量组半衰期平均为64.68±22.90h。LHRH的药—时曲线符合二室模型,大剂量LHRH和小剂量LHRH的主要药动学指标差别不大。结论:LHRH在大鼠体内的消除模式为二室模型,为一级动力学消除。  相似文献   
992.
We describe two brothers and a cousin with common clinical features, including mild mental retardation, motor delays, hypotonia with truncal ataxia, esotropia, and mild facial and hand dysmorphia. The initial routine chromosome study failed to detect any abnormality in the proband. Based on a high index of clinical suspicion, high-resolution chromosome studies were performed on the proband's parents. A small reciprocal translocation t(10;14) (q26.1;q32.3) was detected in the father. The breakpoint on the derivative chromosome 14 was further placed telomeric to the immunoglobulin heavy-chain gene cluster at the band q32.33 by fluorescence in situ hybridization. Studies of the proband and two affected paternal cousins revealed that each had inherited the same derivative chromosome 10 from their carrier parents. This unbalanced karyotype resulted from an adjacent-1 segregation of the 10;14 translocation.  相似文献   
993.
To investigate the hepatitis B virus (HBV) DNA status in the liver when hepatocellular carcinoma (HCC) has developed, 35 paired nontumorous and tumorous liver tissues from 27 hepatitis B surface antigen (HBsAg)-seropositive and 8 HBsAg-negative patients with HCC were studied by Southern blot analysis. The hybridization patterns of HBV DNA were different in the nontumor and tumor parts in 26 (96.3%) of the 27 HBsAg-positive patients. In the nontumor parts, integration of HBV DNA into the host genome was significantly less when compared to the tumor parts (15/27 vs. 25/27, P less than 0.05), whereas free replicative viral forms were significantly more frequent (17/27 vs. 7/27). The integrated HBV DNA in the nontumor parts showed discrete band patterns in the majority of cases (13/15). Hepatitis B e antigen (HBeAg) was significantly associated with the expression of free replicative forms of HBV DNA in the tumor tissues. An integrated HBV DNA sequence was detected in the tumor part of one HBsAg-negative patient, but not in her nontumor counterpart. Our observation that discrete integrated HBV DNAs are present in the nontumor part, representing subclinical clonal expansion that precedes the development of HCC, suggests the risk of future new tumor growth from these cell clones.  相似文献   
994.
Cystic fibrosis (CF) is the most common fatal autosomal recessive multisystem disorder, which occurs mainly in European-derived populations. The incidence of CF varies between 1 in 2000 to 3000 live-births in various ethnic groups. The disease is rare in East Asians. Here we report a 9 year old Thai male patient, who was diagnosed to have CF based on recurrent pneumonia, a slow weight gain, pancreatic insufficiency and repeatedly elevated sweat chloride levels by two different methods. A comprehensive genetic analysis showed the splicing mutation, 1898+ 1G-->T, which was apparently of maternal origin. Literature search found 39 documented cases of CF patients in East Asians. CFTR (MIM# 602421) genotyping was performed in 14 patients including our patient and in 9 of them a CF allele was identified. The findings seem to indicate that the splicing mutations, 1898+ 1G-->T and 1898+ 5G-->T are more common in East Asian CF patients.  相似文献   
995.
Dopamine plays important roles in the regulation of central nervous system (CNS) development and functions. In vertebrates, two families of dopamine receptors, collectively known as dopamine D1 and D2 receptors, have been identified. Recently, dopamine receptors have been targeted by pharmacological and therapeutic studies of neurological disorders, such as Parkinson's disease. Here, we report a study on the molecular characterization of dopamine D1 receptor in zebrafish (Danio rerio). We cloned the full-length cDNA of a zebrafish dopamine D1 receptor, designated as drd1. The sequence of drd1 shares high homology to the sequences of dopamine D1 receptors in mammalian, amphibian, and other fish species. drd1 is expressed in the CNS. The first drd1 expression was observed at approximately 30 hours postfertilization, at which time the expression was seen in the developing diencephalon and hindbrain. In developing retinas, the expression of drd1 was detected in the inner nuclear layer with the exception of the marginal zones. In adult retinas, drd1 expression was detected in most cell types in the inner and outer nuclear layers as well as ganglion cell layer. Differential expression of drd1 in developing and adult retinas may play various roles in regulating visual system functions.  相似文献   
996.
Vesicular stomatitis virus (VSV), when reproduced in human tumor cell lines, assembled a specific subset of cell-derived proteins. These were detected by [35S]methionine labeling of cells prior to infection and subsequent immunoprecipitation of VSV grown in these cells, as well as by direct immunoprecipitation of labeled cell extracts with antiserum directed against the VSV-assembled proteins. Their molecular weight (Mr) ranged between 15K and 180K; the larger proteins were glycosylated. Two of the major protein species (gp88 and gp130) were common to all four cell lines used (HeLa—cervical carcinoma, T47D—breast carcinoma, and HMB2 and SK1477—two melanoma cell lines). Proteins of other molecular weights were detected only in one or two of the cell lines. The melanoma cell lines (even in the absence of VSV) shed large particulate material which had contained the same spectrum of proteins that were assembled by VSV. The major protein component had an Mr of 30K. Some of the VSV-assembled proteins might possibly serve as specific tumor markers. It is also conceivable that the proteins assembled by VSV as well as the large particulate material might be products of defective endogenous human retroviruses.  相似文献   
997.
米非司酮对体外培养人子宫内膜的损伤作用   总被引:7,自引:0,他引:7  
目的 探讨米非司酮对体外培养人子宫内膜的损伤作用。方法 取 5位育龄妇女增殖期的子宫内膜组织并分成两份。一部分用含 15 %胎牛血清及 1%青霉素和链霉素的DMEM培养液培养 (对照组 ) ,另一部分在另加 2 5 μg/ml米非司酮的培养液培养 (米非司酮组 )。 10 0h后取出组织制备电镜样品并观察。结果 对照组的子宫内膜腺上皮出现核仁管道系统(NCS)、巨大线粒体及糖原沉积等分泌期的 3大形态特征。米非司酮组则不仅未见上述特征 ,还出现了线粒体空泡化、腺细胞成片坏死及间质水肿的现象。结论  (1)NCS在人子宫内膜的形成与孕激素无直接关系 ;(2 )在缺乏孕激素的作用下 ,增殖期的子宫内膜仍然可转化为分泌期的形态 ;(3)米非司酮可直接造成人子宫内膜的损伤。  相似文献   
998.
A key advantage in the conversion from film-based to digital radiology is the possibility of a long-term on line electronic archival of patient studies. The popular approach based on optical disk jukeboxes for the long-term archive and magnetic disk storage for data caching is not economically attractive because of the cost of both the jukebox and the medium. Strategies for extending the archival system design with a tape jukebox have been studied. The proposed strategy calls for the use of high-ratio lossy compression together with low-cost tape storage to make long-term on line archiving more affordable. An intelligent prefetching algorithm based on hospital information system and radiologic information system triggers, which in turn are augmented by manual case preparation, can effectively overcome the longer latency of ad hoc retrievals. This longer latency is caused by both system-level bottlenecks and the sequential access constraint of the tape drive. Strategies for image clustering and tape allocation by patient classification also enhance retrieval efficiency. This archival design using image compression, prefetching, and clustering could be implemented in many of the existing teleradiology and picture archiving and communication systems.  相似文献   
999.
高压氧促进成年大鼠神经干细胞的增殖   总被引:5,自引:0,他引:5  
目的:研究高压氧对成年大鼠神经干细胞增殖的影响。方法:采用BrdU免疫组化方法,观察高压氧对成年大鼠神经干细胞增殖的影响,同时通过脑内注射内皮素制备大脑中动脉闭塞(MCAO)模型,对这两种诱导神经干细胞增殖的处理加以比较。结果:高压氧暴露10d,侧脑室前角和外侧壁的BrdU~ 细胞数量显著增加,BrdU~ 细胞核计数显著多于正常组,阳性细胞核反应性也显著增强,多为深染的棕黑色细胞核,其效应与MCAO第8天对BrdU~ 细胞的效应类似;高压氧暴露10d也引起了海马齿状回颗粒细胞层BrdU~ 细胞数量显著增加。结论:反复高压氧暴露可能具有调节脑内神经干细胞增殖与分化的作用。  相似文献   
1000.
p53基因是各种人类肿瘤包括食管癌中最常见有突变的基因之一。我们应用激光显微切割,聚合酶链反应(PCR)-杂合性缺失(LOH),PCR-单链构象多态性分析(SSCP),p53测序及免疫组织化学方法,检测了食管癌高发区中国山西省的56例患者食管鳞状细胞癌(ESCC)中p53基因缺失、突变及p53蛋白表达情况,旨在更好理解p53基因突变等变化在食管癌发生发展过程中的作用。  相似文献   
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