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81.
目的研究山东地区汉族人群4个STR位点(D10S1248、D14S1434、D22S1045、SE33)的遗传多态性.方法运用PCR扩增、8%非变性聚丙烯酰胺凝胶电泳结合银染技术对152个无关汉族人群个体进行多态性研究.结果4个位点分别检测出72、80、72、136个等位基因片段,共有53个基因型,其频率分布在0.0526~0.1579之间,经检测其多态性分布符合Hardy-weinberg平衡定律.4个STR位点多态信息量(Polymorphism information content,PIC)分别为0.8493、0.8785、0.8173、0.9157.期望杂合度(Heterozygosity,HET)分别为0.8643、0.8892、0.8374、0.9211.结论山东地区汉族该4个STR基因座位点的多态性数据显示其基因分布特征具有特异性.  相似文献   
82.
肌肉生长抑制素(MSTN)属于转化生长因子超家族,是主要在骨骼肌中特异性表达且功能比较专一的肌肉发育负调控因子.鱼类的MSTN基因比较复杂,具有不同的同源基因.本文综述了鱼类MSTN基因的结构、种类、时空表达特征,MSTN的作用机理及生物学功能,鱼类MSTN基因多态性研究以及MSTN基因在鱼类生产中潜在的应用前景.  相似文献   
83.
A total of 64 patients with β-lactam allergy and 30 control subjects were enrolled in a case-control study. This study is aimed to analyze the relationship between β-lactam allergy and 10 single nucleotide polymorphisms (SNPs) in interleukin-10 (IL-10), IL-13, IL-4Rα, high-affinity immunoglobulin E-receptor β chain (FcεRIβ), interferon γ receptor 2 (IFNGR2), and CYP3A4, and within the Han Chinese population of Northwest China. Genotyping for the SNPs was conducted using the Sequenom MassARRAY®platform. SPSS 17.0 was employed to analyze the statistical data and SHEsis was used to perform the haplotype reconstruction and analyze linkage disequilibrium of SNPs of IL-10 and IL-13. The results showed that the genotype distribution of CYP3A4 rs2242480/CT differed significantly between case and control groups of males (P=0.022; odds ratio (OR)=0.167, 95% confidence interval (CI): 0.032–0.867). Further analysis showed that CCA, CCG, and TAA haplotypes of IL-10 had no significant correlation in patients with β-lactam allergy. The correlation between CCT and CAC haplotypes of IL-13 and β-lactam allergy needs to be further studied. The analysis did not reveal any differences in the distribution of others gene polymorphisms between cases and controls.  相似文献   
84.
85.
摘要:目的:探讨肾素-血管紧张素-醛固酮系统(RAAS)基因多态与男性原发性高血压患者不同强度有氧运动降压效果的关系,为制定个性化运动处方提供依据。方法:78名男性原发性高血压患者利用聚合酶链式反应(PCR)测定血管紧张素转化酶(ACE)基因I/D、血管紧张素II 1型受体(AT1R)基因A/C和醛固酮合酶(CYP11B2)基因T/C多态。所有受试者分别以60%VO2max进行一次中等强度有氧运动实验(MAET)、以40%VO2max进行一次低强度有氧运动实验(LAET)以及1次安静对照实验(RCT),时间均为40 min。每次实验前后测定24 h动态血压(ABP),包括收缩压(SBP)和舒张压(DBP)。结果:各基因型分布频率均符合哈-温遗传平衡定律(P>0.05)。与实验前比较,MAET、LAET后各基因型组血压水平均显著性下降(P<0.05),RCT后则无显著性变化(P>0.05);LAET后,ACE-DD基因型组SBP低于ACE-II/ID基因型组(P<0.05)。LAET后,≥3个RAAS高危等位基因组SBP和DBP均低于≤2个高危等位基因组(P<0.05);MAET和RCT后,两组血压水平均无显著性差异(P>0.05)。结论:RAAS基因多态可影响急性有氧运动的降压效应。ACE-DD基因型携带者低强度有氧运动的降压效果优于ACE-I等位基因(II/ID)者;≥3个RAAS高危等位基因患者低强度有氧运动的降压效果优于≤2个等位基因变异者;中等强度运动以及安静对照实验后,血压无显著性改变。  相似文献   
86.
Homocysteine concentration affected by the activities of the enzymes methylene tetra-hyrdofolate reductase (MTHFR). Polymorphisms in MTHFR gene associated with an impairment of MTHFR activity. Hyperhomocysteinemia is a result of single nucleotide polymorphisms (SNPs) in MTHFR 677 C>T that can cause homocysteine levels in the blood to increase. The purpose of this study is to investigate the relationships between MTHFR C677T (rs1801133) gene polymorphism, changes in homocysteine concentrations and progress of renal impairment in young adult hypertensive patients. Two hundred young hypertensive patients (age 21–24 years) were involved in this study; they were classified into patients with and without renal impairment in addition to 200 age and sex matched healthy controls. All participants were submitted to laboratory investigations as assay of MTHFR gene polymorphism C677T (rs1801133) by PCR/RFLP, determination of lipid profile, homocysteine and folic acid concentrations in addition to urinary albumin creatinine ratio (UACR). The levels of both homocysteine and UACR in the TT genotype patients were higher than those in the CC genotype group. Individuals who carry the T allele were more risky to hypertension and progress to early renal impairment in young age compared with those carrying the C allele [OR 2.02 (1.33–3.08), P < 0.001]. Genetic variants of C677T MTHFR gene and hyperhomocysteinemia may be responsible for rapid progress of renal impairment in Egyptian young age hypertensive patients. TT genotype or T allele may be considered as a predisposing factor for both elevated Hcy levels and the development of renal impairment. This study believed that lowering of homocysteine level can reduce renal impairment of hypertensive patients.  相似文献   
87.
为了对本课题组得到的大批优质棉花种质资源进行RAPD分子标记遗传多样性鉴定,我们进行了对棉花有效的引物对的筛选,并完成了24个优质棉花材料的遗传多样性分析.结果从48个随机引物对中筛选出了20对引物,这些引物对这24个优质棉花材料的有效性非常高,共扩增出113条谱带,平均每个引物扩增出5.65条,而且这20个随机引物对这24个材料的多态性谱带扩增效果非常明显,多态率高,能明显分辨出来源不同的材料.将这些多态性标记通过聚类软件分析,可将这24种材料明显的分为六类群,遗传多态性得到明显的体现.  相似文献   
88.

Introduction:

Metabolic syndrome (MetS) is a multifactorial disorder in which dyslipidemia plays an important role. Fatty acid-binding protein 2 (FABP 2) is responsible for transport of free fatty acids in the intestinal endothelium cells. FABP2-genetic variants might affect plasma lipid concentrations and intracellular lipid transport. The aim of this study was to investigate the association between FABP2 Ala54Thr genetic polymorphism and metabolic syndrome and some biochemical and anthropological parameters in elderly subjects.

Materials and methods:

This cross-sectional study included 140 men and 176 women older than 70 years. Fasting serum concentration of glucose, lipid parameters, total proteins and C-reactive protein were determined by standardized methods. Presence (MetS(+)) or absence (MetS(−)) of MetS was determined according to criteria of the International Diabetes Federation. FABP2 genetic polymorphism Ala54Thr (rs1799883) was genotyped with PCR-RFPL.

Results:

The genotype frequencies for Ala/Ala, Ala/Thr and Thr/Thr genotype were 60, 36 and 6 in MetS(−), and 131, 70 and 13 in MetS(+), respectively, without statistical significance (P = 0.567). Ala/Ala genotype was a subgroup of non-carriers, while Ala/Thr and Thr/Thr genotypes were Thr54-carriers. Median triglyceride concentration was significantly lower in carriers then in non-carriers for whole MetS(+) group (P = 0.050); there were no significant difference between men with MetS (P = 0.144), but there was a difference between women with MetS (P = 0.020). T-test showed that mean HDL cholesterol concentrations in MetS(+) group for Thr54-carriers was significantly higher in whole group (P = 0.001), and for both genders (men P = 0.039; women P = 0.004) as compared to non-carriers.

Conclusions:

FABP2 genetic polymorphism is associated with lower triglyceride and higher HDL-cholesterol concentrations in elderly subjects with MetS. This genetic variation might be a useful marker for understanding dyslipidemia in MetS.  相似文献   
89.
目的:应用数目可变串联重复序列(VNTR)分子分型技术,对大理地区60株肺结核临床分离株进行分型研究,探讨大理地区菌株DNA多态性及基因型特征。方法:采用VNTR分子分型技术对60株结核分枝杆菌3个VNTR位点进行检测,应用Quantity one软件和BioNumerics 6.6软件进行聚类分析。结果:60株结核分枝杆菌可以分为4个基因群(Ⅰ群、Ⅱ群、Ⅲ群、Ⅳ群),28个基因型。Ⅰ群占15.0%,含有5个基因型,Ⅱ群占31.7%,含有8个基因型,Ⅲ群占40.0%,含有11个基因型,Ⅳ群占13.3%,含有4个基因型。结论:大理地区的结核分枝杆菌存在基因多态性,其主要流行群为Ⅲ群。  相似文献   
90.
研究目的 :探讨了 mt DNA D- loop多态性与澳大利亚自行车运动员的 VO2 max及优异耐力成绩的关系。研究结果 :前期研究发现虽然运动员组和对照组 VO2 max有显著性差异 ,但 mt DNA D- loop的多态性在两组的分布频率没有显著性差异  相似文献   
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