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71.
AMPKα2基因多态性作为中国北方汉族人群心脏耐力训练敏感性分子标记的可行性研究 总被引：1，自引：0，他引：1
目的:研究腺苷酸激活的蛋激酶α2亚基(AMPKα2)基因区的7个标签单核苷酸多态性位点(SNP)及其组成的单体型与有氧耐力训练前后心脏结构和功能敏感性指标变化之间的相关性,探讨其作为有氧耐力训练敏感性分子标记的可行性。方法:对102名中国北方汉族青年进行为期18周的有氧耐力训练,测定训练前后安静时、不同负荷状态下(50 W、100 W、150 W)以及恢复期的心脏结构和功能相关指标。采用MALDI-TOF MS方法解析受试者基因组DNA多态位点基因型,分析训练前后相关指标的变化与基因型之间的关联性。结果:1)rs1418442、rs11206889以及部分单体型与心脏结构指标室间隔舒张末厚度(IVSD)和左心室质量指数(LVMI)的训练敏感性相关联;2)部分单体型与心脏功能指标150 W负荷下每搏输出量指数(SVI)的训练敏感性相关联。结论:AMPKα2基因的部分基因型或单体型可以作为中国北方汉族人群心脏对耐力训练敏感的分子标记。 相似文献
72.
目的:研究低氧和低氧训练对AMPKα2转基因小鼠骨骼肌CPT-1的mRNA和蛋白表达水平的影响,进而探讨低氧和低氧训练中AMPKα2调节脂肪酸氧化过程的可能机制。方法:健康两月龄C57BL/6J品系的野生小鼠和AMPKα2转基因小鼠,分别分为常氧安静组、低氧安静组和低氧训练组,共六组,每组10只。低氧组小鼠持续暴露于低氧房中(模拟海拔4000m高度,氧浓度12.3%),其中低氧训练组小鼠还要在此低氧房中进行跑台运动,12m/min,每天1h,持续2周。测定股四头肌AMPKα2蛋白水平以及CPT-1的mRNA和蛋白表达情况。结果:2周的低氧和低氧训练对AMPKα2的蛋白表达没有显著的影响;低氧和低氧训练均显著提高了CPT-1的mRNA表达(P<0.05);低氧对野生和AMPKα2转基因小鼠CPT-1的作用无差异;低氧训练组中,AMPKα2转基因小鼠的CPT-1 mRNA表达显著高于野生小鼠(P<0.05),与低氧安静组相比,低氧训练使转基因小鼠的CPT-1蛋白表达产生了显著增加(P<0.05),但是野生小鼠并无显著变化。结论:AMPKα2参与调节了低氧训练中骨骼肌CPT-1的表达水平,促进脂肪酸的氧化过程。 相似文献
73.
在复Cn空间的单位球Bn上已经有了星形映照、螺形映照的3个扩充子类：α次殆β型螺形映射、α次β型螺形映射、α次强β型螺形映射,但这3个子类存在支持不够充足。以复分析和泛函分析为工具,在Reinhardt域Ωp1…pn上给出了这3种子类的一种构造方法,该结论对单位球Bn同样成立。 相似文献
74.
Xuya Shang Zongyu Li Xuecheng Cao Chen Xie Mingyong Gu Pei Chen 《Journal of sports sciences》2015,33(17):1775-1779
Ankle sprains are one of the most severe musculoskeletal soft tissue injuries during physical activity. Although many risk factors have been offered, it is unclear why some individuals develop noncontact ankle sprains when participating in comparable levels of physical exertion under identical environmental conditions and others do not. The ACTN3 gene that encodes the α-actinin-3 protein, which is, only expressed in the Z line of fast glycolytic muscle fibres was found to associate with power/strength performance. The aim of this study was therefore to investigate whether the ACTN3 gene polymorphism is associated with noncontact acute ankle sprains. One hundred and forty-two participants with clinically diagnosed noncontact acute ankle sprains as well as 280 physically active controls participants without any history of ankle sprains were included in this case–control genetic association study. The RR genotype (odds ratio (OR) = 0.56; 95% confidence interval (CI), 0.32–0.65, P = 0.011) and R allele (OR = 0.64; 95% CI, 0.37–0.68, P = 0.002) of the ACTN3 were significantly low-represented in the acute ankle sprains group compared with the control group. The ACTN3 R577X is associated with acute ankle sprains in Chinese participants in this study. This is the first study to suggest that an individual with a RR genotype is at a decreased risk of acute ankle sprains. 相似文献
75.
AbstractInterest in Vitamin D has risen considerably recently with many athletes now advised to take daily vitamin D supplements. The reason for this interest is partly not only attributed to the resurgence of the Vitamin D-deficient disease rickets but also due to the discovery of a Vitamin D receptor in many tissues suggesting a more global role for Vitamin D than previously considered. Unlike the other vitamins that are obtained through the diet, Vitamin D is unique since endogenous synthesis following ultraviolet B (UVB) exposure is the predominant route of entry into systemic circulation. Moreover, Vitamin D could be better classed as a seco-steroid, given that its structure is similar to that of a steroid, and its production is derived from a cholesterol precursor (7-dehydrocholesteol) in the skin. The classification of Vitamin D status is currently subject to considerable debate with many authors opposing governing body recommendations. Regardless of the suggested optimal concentration, there is now growing evidence to suggest that many athletes are in fact Vitamin D deficient, especially in the winter months largely as a consequence of inadequate sun exposure, combined with poor dietary practices, although the consequences of such deficiencies are still unclear in athletic populations. Impaired muscle function and reduced regenerative capacity, impaired immune function, poor bone health and even impaired cardiovascular function have all been associated with low Vitamin D in athletes, however, to date, the majority of studies on Vitamin D have described associations and much more research is now needed examining causation. 相似文献
76.
翁振翔 《宁德师专学报(自然科学版)》2012,24(2):184-186
金针菇属食、药两用真菌,具有很好的经济价值和保健功能,市场前景良好.探讨在原有培养基的基础上添加不同剂量的α-萘乙酸,分析比较其对金针菇产量的影响,从而筛选出最佳生产剂量. 相似文献
77.
黄芪水提物对α-葡萄糖苷酶活性的抑制及其降血糖作用 总被引：1，自引：0，他引：1
应用黄芪水提物与不同浓度的α-葡萄糖苷酶,不同浓度的底物PNP-glucoside进行反应,研究中药黄芪中α-葡萄糖苷酶抑制剂的抑制活性及其对正常小鼠血糖和糖耐量的影响.通过绘制酶量-反应速度曲线和双倒数曲线,确定其抑制剂类型,并对正常小鼠以40～160 mg.kg-1剂量灌胃后,观察其对血糖值和糖耐量的影响.结果表明,黄芪中α-葡萄糖苷酶抑制剂为可逆、非竞争性抑制;可降低正常小鼠血糖值,并且以80 mg.kg-1的剂量时血糖值最低,还可显著提高小鼠糖耐量.黄芪水提物中含有α-葡萄糖苷酶抑制剂成分,可用于糖尿病治疗. 相似文献
78.
基于极大模糊熵原理的模糊推理三Ⅰ约束算法 总被引：1，自引：1，他引：0
彭家寅 《内江师范学院学报》2010,25(8):5-13
给出了FMP,FMT问题的模糊熵三Ⅰ约束原则,讨论了FMP,FMT问题的模糊熵三Ⅰ约束解的存在性条件,分别给出了几个常见蕴涵算子的FMP问题与FMT问题的模糊熵三Ⅰ约束算法的计算公式,进一步将问题一般化;给出了FMP问题与FMT问题的模糊熵α-三Ⅰ约束解的存在性条件,并得到了基于这些蕴涵算子的模糊熵α-三Ⅰ约束算法相应的计算公式。 相似文献
79.
α-吡啶甲酸铜超分子配合物的合成、晶体结构及电化学性质 总被引：1，自引：0，他引：1
以α-吡啶甲酸为配体,运用溶剂挥发法,合成了一种超分子配合物α-吡啶甲酸铜{Cu（C5H4NCOO）2.2H2O}m,用红外光谱、紫外-可见光谱对配合物进行了表征,用X-射线单晶衍射测定了配合物的单晶结构.配合物为三斜晶系,P1-（2）空间群,晶胞参数：a=0.51291（11）nm,b=0.76367（17）nm,c=0.9226（2）nm,α=74.914（3）°,β=84.346（3）°,γ=71.463（3）,°V=0.33077（44）nm3,Z=1.采用循环伏安法研究了配合物在水溶液中的电化学性质. 相似文献
80.
探讨常压下模拟低氧(氧体积分数13.6%)训练对大鼠脑组织Ngb、HIF-1α、Bax和Bcl-2的影响,为运动和低氧适应提供理论参考。将50只9周龄雄性SD大鼠随机分为低住安静组、低住低练组、高住安静组、高住低练组和高住高练低练组,每组10只。训练组大鼠进行跑台训练,强度为常氧下35 m/min、低氧下30 m/min,持续运动1 h/d,5 d/周,持续4周。实验结束后,采用ELISΑ试剂盒分别检测大鼠脑组织Ngb、HIF-1α、Bax和Bcl-2水平,并计算Bax与Bcl-2的比值。结果发现:(1)与低住安静组比较,低住低练组HIF-1α、Bax和Bax/Bcl-2均升高(P<0.05或P<0.01);高住安静、高住低练和高住高练低练组的Ngb、HIF-1α、Bax和Bcl-2均升高(P<0.05或P<0.01)。(2)与低住低练组相比,高住安静、高住低练和高住高练低练组的HIF-1α和Bcl-2均升高(P<0.01);高住低练和高住高练低练组的Bax/Bcl-2降低(P<0.01);高住高练低练组的Ngb升高(P<0.01)。(3)与高住安静组相比,高住低练组和高住高练低练组的HIF-1α、Bcl-2均升高(P<0.05或P<0.01);高住高练低练组的Ngb升高(P<0.01),Bax/Bcl-2降低(P<0.05)。(4)与高住低练组相比,高住高练低练组Bcl-2升高(P<0.01)。(5)Ngb表达和HIF-1α表达呈正相关(r=0.563,P<0.01);Ngb表达与Bax/Bcl-2变化呈正相关(r=0.486,P<0.01);HIF-1α表达与Bax/Bcl-2变化呈正相关(r=0.353,P<0.05)。结果表明:单纯训练刺激会引起大鼠脑组织HIF-1α升高,单纯低氧刺激会引起大鼠脑组织Ngb和HIF-1α升高,当训练和低氧这两种因素相互结合时,Ngb和HIF-1α的升高更明显。高住高练低练对大鼠脑组织Bcl-2的影响要大于高住低练。Ngb和HIF-1α的升高,使Bax/Bcl-2向着有利于神经元存活的方向发展,提示Ngb和HIF-1α参与了中枢神经系统的缺氧耐受和自我保护。 相似文献