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51.
高密度脂蛋白参与的胆固醇逆向转运被认为具有抗动脉粥样硬化作用,是冠心病的保护因子。胆固醇酯转运蛋白是胆固醇逆向转运的关键蛋白质,是血浆高密度脂蛋白水平的主要决定因素之一。对其结构和功能以及其与血脂及动脉粥样硬化的关系进行深入的研究,是当今一热点,将为阐明动脉粥样硬化的分子病理机制和探索动脉粥样硬化的防治措施提供依据。  相似文献   
52.
本文运用检测方法,对女子举重运动员比赛期间的心电图、尿蛋白及血红蛋白等变化进行测试与分析。结果表明,女子举重运动员在比赛期间,心室壁没有增厚;尿蛋白变化较大,其排出量有性别差异;血红蛋白浓度变化不大。  相似文献   
53.
运动与热休克蛋白表达   总被引:7,自引:0,他引:7  
运用文献资料法,对运动与热休克蛋白表达及其相关进行了综述,并就其在运动与训练中的损伤保护及防止过度训练等潜在研究价值,进行了探讨。  相似文献   
54.
骨骼肌损伤的机制   总被引:2,自引:0,他引:2  
用电镜和免疫电镜观察超过习惯负荷后人骨骼肌收缩结构和收缩蛋白定位延迟性变化的结果提示:超过习惯负荷后延迟发生的骨骼肌收缩蛋白的降解优势导致收缩结构的改变或解体。这种收缩结构的改变构成了后继负荷工作的背景,如后继负荷能促进收缩蛋白的合成则可促进收缩结构的恢复和增强;如后继负荷导致收缩蛋白降解优势的积累和稳定,则将引起收缩结构变化的积累和稳定而导致骨骼肌的慢性或急性损伤。这种变化的一过性和两向发展的可能性提示:在未形成稳定的变化之前,其变化性质是生理的或是生理—病理双向变化的过渡的性质。骨骼损伤的预防主要在于是否根据承受能力的可能性而适当地安排工作负荷  相似文献   
55.
目的:观察补充糖饮料、支链氨基酸和乳清蛋白等能量物质对阶段性大运动量训练维持或提高运动员身体机能和疲劳恢复的影响。方法:根据冬训阶段性训练计划安排,对10名散打运动员在30d的体能训练阶段,按营养补充方案进行能量补充,观察能量补充对机体无氧能力的输出总功、最大功率、疲劳指数,有氧能力的拉桨时间、功率、桨频,生化指标血乳酸(LA)尿素氮(BUN)、血糖(GL)、肌酸激酶(CK)的影响,另选10名队友作空白组,进行自身前后对照和空白对照。结果:观察组经过阶段性能量补充前后运动员的输出总功、最大功率、疲劳指数和桨频均显著提高(P〈0.01),与空白组相比也有明显提高(P〈0.05),训练课后血糖水平也明显提高(P〈0.05),补充支链氨基酸和乳清蛋白后血BUN的恢复与空白组比有极显著好转(P〈0.001)。结论:训练期间补充糖、支链氨基酸和乳清蛋白等能量物质,能明显改善运动员的有氧运动能力和无氧运动能力,明显延缓运动性疲劳的发生,加速运动性疲劳恢复的作用。  相似文献   
56.
To analyse the association of high sensitivity C-reactive (hsCRP) protein levels and −717A/G single nucleotide polymorphism of CRP with acute myocardial infarction (AMI) in the Indian population. Study population included 100 MI cases wherein 32 patients had experienced previous MI (MI-Group-1), 68 MI cases were recruited at presentation (MI-Group-2) and equal number of age and gender matched healthy individuals. hsCRP levels were determined by ELISA and genotyping of −717A/G was carried out by polymerase chain reaction-based restriction digestion method. The −717A/G genotypes did not influence hsCRP level and their distribution did not differ between groups. However, in the present study hsCRP demonstrated significant correlation with BMI in controls of both the genders and with triglycerides in females of AMI at presentation who otherwise are with low risk profile. Identifying traditional risk factors associated with inflammation may help in controlling the acute event.  相似文献   
57.
蛋白质晶体的生长过程是蛋白质分子与周围环境相互作用的结果.蛋白质晶体的生长分为成核、生长和停止三个阶段.对蛋白质的结晶条件进行筛选、种晶可获得晶核.通过改变蛋白质本身来获得单晶的方法有:截短、修饰、共晶和寻找同源蛋白质.蛋白质的结晶条件仍有待于进一步深入研究.  相似文献   
58.
Mesenchymal stem cell(MSC)transplantation has shown a therapeutic potential to repair the ischemic and infracted myocardium,but the effects are limited by the apoptosis and loss of donor cells in host cardiac microenvironment.The aim of this study is to explore the cytoprotection of heat shock protein 90(Hsp90)against hypoxia and serum deprivation-induced apoptosis and the possible mechanisms in rat MSCs.Cell viability was determined by3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide(MTT)assay.Apoptosis was assessed by Hoechst 33258nuclear staining and flow cytometric analysis with annexin V/PI staining.The gene expression of Toll-like receptor-4(TLR-4)and V-erb-b2 erythroblastic leukemia viral oncogene homolog 2(ErbB2)was detected by real-time polymerase chain reaction(PCR).The protein levels of cleaved caspase-3,Bcl-2,Bcl-xL,Bax,total-ERK,phospho-ERK,totaI-Akt,phospho-Akt,and Hsp90 were detected by Western blot.The production of nitric oxide was measured by spectrophotometric assay.Hsp90 improves MSC viability and protects MSCs against apoptosis induced by serum deprivation and hypoxia.The protective role of Hsp90 not only elevates Bcl-2/Bax and Bcl-xL/Bax expression and attenuates cleaved caspase-3 expression via down-regulating membrane TLR-4 and ErbB2 receptors and then activating their downstream PI3K/Akt and ERK1/2 pathways,but also enhances the paracrine effect of MSCs.These findings demonstrated a novel and effective treatment strategy against MSC apoptosis in cell transplantation.  相似文献   
59.
Bone morphogenetic proteins (BMPs) play a critical role in the growth and steroidogenesis of granulosa cells (GCs). BMP signals act through membrane-bound heteromeric serine/threonine kinase receptors. Upon ligand binding, BMPs activate intracellular Smad proteins and regulate growth and apoptosis in various cell types. The objective of this study was to demonstrate the effects of BMP/Smad signal on growth and steroidogenesis of porcine GCs. A strategy of RNA interference (RNAi)-mediated ‘gene silencing’ of Smad4, a core molecule mediating the intracellular BMP/Smad signal transduction pathways, was used to interrupt endogenous BMP/Smad signaling. Results indicate that Smad4-small interfering RNA (siRNA) caused specific inhibition of Smad4 mRNA and protein expression after transfection. Interrupted endogenous BMP/Smad signaling significantly inhibited growth, and induced apoptosis of porcine GCs, while decreasing estradiol production. In addition, interrupted BMP/Smad signaling significantly (P<0.05) changed the expression of Cyclin D2, CDK4, Bcl-2, and Cyp19a1. These findings provide new insights into how BMP/Smad signaling regulates the growth and steroidogenesis of porcine GCs.  相似文献   
60.
In this paper,we investigate the effect and the possible mechanism of high glucose levels on the calcification of human aortic smooth muscle cells (HASMCs).HASMCs were divided into four groups: normal glucose group (NG),osmolality control group (OC),high glucose group (HG,HASMCs culture medium containing 30 mmol/L glucose),and high glucose plus recombinant human Noggin protein (bone morphogenetic protein-2 (BMP-2) antagonist) group (HN).The mRNA levels and the protein expressions of BMP-2 and core binding factor alpha-1 (Cbfα-1) were measured by real-time quantitative polymerase chain reaction (PCR) and Western blot.After induced by 10 mmol/L β-glycerol phosphoric acid,cells were harvested for assessments of alkaline phosphatase (ALP) activities at Days 1,2,and 3,and intracellular calcium contents at Days 7 and 14,respectively.High glucose levels increased the mRNA levels and the protein expressions of BMP-2 and Cbfα-1 (P0.05).The expression of Cbfα-1 was partially blocked by Noggin protein (P0.05),while BMP-2 was not (P0.05).After being induced by β-glycerol phosphoric acid,high glucose levels increased the ALP activity [(48.63±1.03) vs.(41.42±2.28) U/mg protein,Day 3;P0.05] and the intracellular calcium content [(2.76±0.09) vs.(1.75±0.07) μmol/mg protein,Day 14;P0.05] in a time-dependent manner when compared with the NG group,while the ALP activity could not be blocked by Noggin protein [(48.63±1.03) vs.(47.37±0.97) U/mg protein,Day 3;P0.05].These results show that high glucose levels can evoke the calcification of HASMCs by inducing osteoblastic trans-differentiation and intracellular calcium deposition via the BMP-2/Cbfα-1 pathway,which can be partially blocked by Noggin protein.  相似文献   
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