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31.
32.
To elucidate whether any relationship exists between genetic polymorphic acetylation and the risk for multiple sclerosis (MS), we determined this polymorphism, using sulphamethazine, in 71 patients with definite MS and in 268 age-matched controls. Thirty-seven patients (52.1%) and 151 controls (56.3%) were classified as slow acetylators (not significant difference). No relation was found between acetylator polymorphism and age at onset of disease in MS patient's group. Our results do not support the existence of any relationship between acetylator polymorphism and the risk for MS.  相似文献   
33.
BACKGROUND: Susceptibility to asthma is known to involve genetic factors. Genome-wide screens have indicated that the chromosome 5q31-q34 region is linked to and/or associated with asthma. A new gene, named UGRP1 and reported by Niimi et al., encodes uteroglobin-related protein and is expressed in the lung and trachea. Niimi et al. showed the -112G/A polymorphism of the UGRP1 gene to be associated with asthma in a case-control study. OBJECTIVE: The objective of the present study was to replicate this association and confirm the possible role of the UGRP1-112G/A polymorphism in the aetiology of childhood asthma in a Japanese population. METHODS AND RESULTS: We conducted a transmission disequilibrium test (TDT) in 131 families identified through paediatric patients being treated for asthma. A case-control study was also carried out by comparing the probands and 137 unrelated non-atopic non-asthmatic Japanese children and 211 unrelated healthy Japanese adults. The -112G/A polymorphism was genotyped by the PCR-RFLP method. The TDT revealed that the -112A allele was not preferentially transmitted to asthma-affected children (P=0.85). Neither the presence of at least one A allele in an individual's genotype (sum of the G/A and A/A genotypes) nor the -112A allele was more prevalent among the asthma subjects than among the control subjects. CONCLUSION: Our findings indicate that the UGRP1-112G/A polymorphism does not play a substantial role in genetic predisposition to childhood asthma in this Japanese population.  相似文献   
34.
本文测量了桡骨与尺骨各100例,其中桡骨15项指标,尺骨14项指标。并用IBM·PC—XT计算机DBASEⅢ数据库管理系统进行了统计分析以及用桡、尺骨最大长分别与桡、尺骨其它各项指标间进行直线相关分析,建立了25个回归方程。  相似文献   
35.
本文用限制性内切酶分析(REA)作伴放线放线杆菌(Aa)的鉴定和分型研究,提取Aa染色体DNA,井分别用BamHI、HindⅢ,Sal Ⅰ和Xho Ⅰ消化,作琼脂糖凝胶电泳。结果显示,Aa和嗜沫嗜血杆菌的DNA片段图谱明显不同;分属于两种不同血清型的两株Aa菌株,其DNA片段图谱也明显不同。这表明,REA可用于Aa菌的鉴定和分型,在所用的4种酶中,以Sal Ⅰ和Xho Ⅰ消化的DNA片段图谱差异最明显。  相似文献   
36.
本实验以免载体股直肌为实验模型,研究了该肌在一定脉冲电流刺激下其初长度与收缩力、肌张力及肌力变化的相互关系。同时测定了正常生理状态下兔伸屈膝时股直肌拉长度的变化。结果表明:兔股直肌延长在1.0cm内时,肌力随初长度的延长而增大,超过1.0cm时增大已不明显(p<0.0 1),1.0cm与股直肌的生理最大延长度1.1cm相似。说明兔股直肌的初长度变化不应超过生理最大延长度。而人的骨骼肌与哺乳动物的骨骼肌没有本质的区别,因此,人骨骼肌的初长度变化也不应超过生理最大延长度。肌腱转位后的活动范围应在原位的生理活动范围内,才能发挥最佳收缩效应。  相似文献   
37.
The recently developed method of total vertical projections is illustrated to estimate the total dendritic length of a human Substantia Nigra neuron. Next, the length of the different orders of dendritic branches, and the mean segment length for each order - commonly regarded as important parameters in neuron physiology - are also estimated. Finally, it is shown how to estimate the mean dendritic length in a population of neurons from vertical slices of arbitrary and unknown thickness. Being unbiased and highly efficient, the proposed methods offer interesting alternatives to current procedures used for the metric analysis of neuron arborizations.  相似文献   
38.
BACKGROUND: Reactive oxygen species may contribute to the pathogenesis of asthma. Functional genetic polymorphisms of antioxidant enzymes, superoxide dismutase (SOD) and catalase are good candidates for asthma susceptibility. OBJECTIVE: To investigate the association of the manganese-containing form of SOD (MnSOD) gene at amino acid position 16 (Val16Ala) and catalase gene in the promoter at A-21T and C-262T polymorphisms and asthma in a Hong Kong Chinese population. METHODS: The association study was conducted in a case-control design in asthma patients (n=251) and healthy controls (n=316) by genotyping. The functional significance was assessed by determining erythrocyte SOD and catalase activity. RESULTS: The Val allele of MnSOD at Val16Ala and the A allele of catalase gene at A-21T were not different between patients and controls, while the C allele of catalase gene at C-262T was found to be significantly different between patients and controls (P=0.033). The less frequent variant of catalase gene (-262T) was found to be protective from the development of asthma in a Hong Kong Chinese non-smoking population (adjusted odds ratio=0.35, 0.15-0.85; P=0.017). Asthma patients had elevated erythrocyte SOD and catalase activities in comparison with healthy controls (P<0.01). However, their activities were not associated with different genotypes within healthy controls or asthma patients. CONCLUSION: This is the first report showing that SOD and catalase functional activities are not associated with their respective genetic polymorphisms but related to the presence of asthma in a Hong Kong Chinese population.  相似文献   
39.
目的 探讨TLR4 (toll likereceptor 4 )Asp2 99Gly、Thr399Ile基因多态性对变应性哮喘的发病和血浆IgE水平的影响。方法 利用聚合酶链反应 限制性片段长度多态性分析技术 (PCR RFLP) ,对 1 97例变应性哮喘患者和 1 5 6例健康人进行TLR4的Asp2 99Gly、Thr399Ile两位点的基因型检测。同时利用免疫发光法检测血浆IgE的水平。结果  1 97例变应性哮喘患者TLR4基因Asp2 99Gly位点Asp Asp、Asp Gly和Gly Gly的基因型频率为 0 .81 7、0 .1 4 7和 0 .0 36 ,与正常对照组相比差异无统计学意义 (χ2 =0 .0 32 ,P =0 .984 ) ;但变应性哮喘患者Gly Gly、Asp Gly基因型血浆总IgE对数值 ( x±s:2 .6 1 5± 0 .6 0 0 1 ,n =36 )与Asp Asp基因型血浆总IgE对数值 ( x±s:2 .2 4 0± 0 .6 894 ,n =1 6 1 )相比较高 ,差异有统计学意义 (P =0 .0 0 2 )。TLR4基因Thr399Ile位点Thr Thr、Thr Ile和Ile Ile的基因型频率为 0 .970、0 .0 2 0和 0 .0 1 0 ,与正常对照组相比差异无统计学意义 (χ2 =0 .6 2 0 ,P =0 .733) ;变应性哮喘患者Ile Ile、Thr Ile基因型血浆总IgE对数值 ( x±s:2 .4 1 7± 0 .4 4 2 3,n =6 )与Thr Thr基因型血浆总IgE对数值 ( x±s:2 .30 5± 0 .6 94 9,n =1 91 )相比差异无统计学意义 (P =0 .5 71 )。  相似文献   
40.
食管癌3p24等位基因LOH及其扩增产物克隆的研究   总被引:4,自引:0,他引:4  
目的;研究3p24EAβMD位点与食管癌的关系。为寻找该位点附近可能存在的抑癌基因奠定基础。方法:采用PCR—RFLP法检测45例食管癌患者3p24位点杂合缺失情况。并对该片段进行克隆。结果:在22例食管癌信息个体中共检出9例杂合缺失。并通过序列分析可知变化为点突变。结论:3p24EAβMD较高的杂合缺失率显示该位点附近可能存在潜在的抑癌基因。  相似文献   
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