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91.
Yen JH  Tsai WC  Chen CJ  Lin CH  Ou TT  Hu CJ  Liu HW 《Immunology letters》2003,88(2):113-116
OBJECTIVES: To investigate the associations of cytochrome p450 1A1 (CYP1A1) and manganese superoxide dismutase (MnSOD) genes polymorphisms with the susceptibility to AS in Taiwan. METHODS: The polymorphisms of CYP1A1 and MnSOD genes were determined in 70 patients with ankylosing spondylitis (AS) and 93 healthy controls by polymerase chain reaction (PCR)/restriction fragment length polymorphisms (RFLP) methods. RESULTS: The genotype frequency of CYP1A1 4887C/A was significantly lower in patients with AS than in controls. The phenotype frequency of CYP1A1 4887A also tended to be decreased in patients with AS. There were no significant differences in the genotype, allele, and phenotype frequencies of MnSOD gene polymorphisms between patients with AS and controls. CONCLUSION: CYP1A1 4887A may be a protective factor for the development of AS in Taiwan. However, MnSOD gene polymorphisms are not associated with the susceptibility to AS.  相似文献   
92.
电镜观察了不同禁水时间老龄大鼠下丘脑视上核和室旁核分泌神经元,即加压素和催产素神经元及胶质细胞的超微结构变化,结果显示,禁水6与12h后,上述两核团中的分泌神经元胞体增大,胞质中粗面内质网(RER)排列紧密且规则,高尔基(Golgi)器的未成熟分泌颗粒及神经分泌颗粒增多,轴突内神经分泌颗粒少见,胶质细胞成份减少,突起回缩;相邻两神经元胞膜直接接触,质膜并列现象及突触增多,而在禁水24h后,神经元胞体内的神经分泌颗粒有减少,轴突中的神经分泌颗粒却增多并聚集成膨大区域,以上结果提示老龄大鼠视上核和室旁核的分泌神经元在禁水时其合成激素的功能是活跃的,而且催产素神经元的结构变化与加压素神经元结构变化是相似的,胶质细胞的结构变化为神经元质膜并列及突触的形式提供了有利条件。  相似文献   
93.
PURPOSE: We developed a microarray for clinical diagnosis of chromosomal disorders using large insert genomic DNA clones as targets for comparative genomic hybridization (CGH). METHODS: The array contains 362 FISH-verified clones that span genomic regions implicated in over 40 known human genomic disorders and representative subtelomeric clones for each of the 41 clinically relevant human chromosome telomeres. Three or four clones from almost all deletion or duplication genomic regions and three or more clones for each subtelomeric region were included. We tested chromosome microarray analysis (CMA) in a masked fashion by examining genomic DNA from 25 patients who were previously ascertained in a genetic clinic and studied by conventional cytogenetics. A novel software package implemented in the R statistical programming language was developed for normalization, visualization, and inference. RESULTS: The CMA results were entirely consistent with previous cytogenetic and FISH findings. For clone by clone analysis, the sensitivity was estimated to be 96.7% and the specificity was 99.1%. Major advantages of this selected human genome array include the following: interrogation of clinically relevant genomic regions, the ability to test for a wide range of duplication and deletion syndromes in a single analysis, the ability to detect duplications that would likely be undetected by metaphase FISH, and ease of confirmation of suspected genomic changes by conventional FISH testing currently available in the cytogenetics laboratory. CONCLUSION: The array is an attractive alternative to telomere FISH and locus-specific FISH, but it does not include uniform coverage across the arms of each chromosome and is not intended to substitute for a standard karyotype. Limitations of CMA include the inability to detect both balanced chromosome changes and low levels of mosaicism.  相似文献   
94.

Background  

The purpose of the present investigation was to determine if the salivary counts of 40 common oral bacteria in subjects with an oral squamous cell carcinoma (OSCC) lesion would differ from those found in cancer-free (OSCC-free) controls.  相似文献   
95.
A colorimetric method of in situ hybridization has been developed for the rapid detection of human immunodeficiency virus (HIV) in formalin-fixed paraffin-embedded material. Following optimization of digestion conditions, biotin-labeled DNA probes are detected with an alkaline phosphatase conjugate. The method is verified using fixed paraffin-embedded cell blocks of HIV-infected and uninfected lymphocyte cell cultures. Hybridization specifically detects both viral RNA and proviral DNA. Formalin fixation for intervals up to 21 d did not significantly hamper the signal under the appropriate digestion conditions; however, Trump's fixation for even 12 h greatly reduced the intensity of the hybridization. This technique for in situ hybridization is amenable to automation, provides results within 6 h, and results in good morphologic preservation. A key feature of the technique is the use of human placental DNA as an endogenous positive control to optimize the empirically determined conditions for protein digestion.  相似文献   
96.
本文首先给出了有关联想记忆的一系列概念,通过计算机模拟验证了网络的某些固有性质,同时指出了它的固有问题,并仿真研究了Hopfield网络中参数间的关系。  相似文献   
97.
BACKGROUND: Randomised controlled trials have shown the efficacy of several treatment modalities for lower urinary tract symptoms (LUTS) in selected populations. The effectiveness in daily practice has hardly been investigated, especially in primary care and is dependent on choices between all possible treatment options and best investigated in a comprehensive study, including all treatment modalities (watchful waiting, alpha-blockers, 5-alpha-reductase inhibitors, and surgery). AIM: Assessment of the effectiveness of a comprehensive treatment protocol for LUTS in primary care. DESIGN OF STUDY: Randomised controlled trial. SETTING: Fourteen general practices in the Netherlands. METHOD: Intervention: treatment protocol based on a formalised expert opinion. Control condition: usual care. Study population: 208 subjects with moderate to severe LUTS (IPSS > or =8, median = 13). OUTCOME MEASURES: symptom severity (IPSS [International Prostate Symptom Score]), bother score (Dan-PSS [Danish Prostate Symptom Score]), and maximum urinary flow (Q(max)); incidence of acute urinary retention and urinary tract infections. RESULTS: In the intervention group markedly more subjects used an alpha-blocker at end of follow-up than in the usual care group (24% versus 6%). No significant differences were found between intervention and control group in IPSS, Q(max) or Dan-PSS. CONCLUSION: alpha-blockers and watchful waiting are the most frequent treatment modalities for LUTS in primary care. Our study showed no evidence that a protocol using well-defined indications for all possible treatment modalities based on a formalised expert opinion procedure has added value. Based on our results, we cannot recommend a broadening of the indication for alpha-blockers, which, however, seems to be the current trend.  相似文献   
98.
目的旨在弄清NS3参与分子间相互作用的确切区段,为研究针对NS3的抗HCV寡肽小分子药物的设计提供依据。方法参照HCV中国河北株序列设计NS3引物,将其N末端的前15个和前30个氨基酸分别缺失掉。然后用酵母双杂交系统检测NS3/NS3及NS3/NS4A分子间相互作用强度在缺失前后的变化,从而判明NS3N末端氨基酸在分子间相互作用中的意义。核苷酸序列分析采用AppliedBiosystem373A型自动测序仪。结果NS3N末端氨基酸缺失前后,NS3/NS3分子间及NS3/NS4A分子间相互作用的强度相差有显著性(P<0.01),但缺失15个氨基酸和缺失30个氨基酸对上述相互作用强度的影响差异无显著性(P>0.05)。结论NS3N末端的1~30个氨基酸在NS3/NS3及NS3/NS4A分子间相互作用中有一定意义,其N末端前15个氨基酸(APITAYSQQTRGLLG)对于分子间相互作用更为关键。本研究结果将为抗NS3丝氨酸蛋白酶活性的寡肽抑制物的研究打下基础,并为抗HCV的寡肽小分子药物的设计提供依据  相似文献   
99.
Cocaine or delta 9-tetrahydrocannabinol (THC), the major psychoactive component of marijuana, has no effect on in vitro cytotoxicity mediated by natural killer (NK) cells and cytotoxic T-lymphocytes (CTL) at concentrations similar to those observed in vivo.  相似文献   
100.
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