Serum dehydroepiandrosterone and lipid peroxides in human volunteers of different age groups     

D. Sreeramulu  B. A. Ramalakshmi  N. Balakrishna  N. Raghuramulu 《Indian journal of clinical biochemistry : IJCB》2004,19(1):79-82

The objective of the present study was to evaluate the changes in serum dehydroepiandrosterone (DHEA) and lipid peroxide levels during ageing in human subjects. Random blood samples were collected from a total of 128 apparently normal human volunteers of both sexes, whose age ranged between 21–70 years. The subjects were divided into groups of a decade years of age difference. Serum levels of dehydroepiandrosterone (DHEA), lipid peroxides as malondialdehyde (MDA), and insulin were analysed in all the subjects recruited in the study. In the present study there was decrease in serum DHEA levels with age (11.30 to 7.99 ng/ml). However the differences were significant only after 50 years up to 70 years. Serum MDA levels of these subjects were higher (3.91 to 4.74 ng/ml) as compared to the values reported earlier (2.64 to 3.94 ng/ml). The serum MDA levels also showed an increasing trend with age but the increase was significant only in the 40–50 years age group and values plateaud off at later ages. The MDA and DHEA levels in women in general were lower than in men and this could be due to female hormones, which are known to protect lipid against peroxidation. There was a significant negative correlation between age and DHEA (r=−0.311 P<0.05) and positive correction between MDA and age (r=+0.405 P<0.01). No significant differences were seen in serum insulin, albumin and total protein levels. These preliminary findings support the possible utility of DHEA and MDA as markers for chronological ageing.  相似文献   

山药多糖抗衰老作用的实验研究   总被引：10，自引：0，他引：10  

唐微  朱明磊  宋明华 《黄冈职业技术学院学报》2002,4(3):23-25

目的:探讨山药多糖的抗衰老作用。方法:将小鼠随机分成对照组、模型组、高剂量用药组、中剂量用药组和低剂量用药组等五个不同的实验组,小鼠每天注射D-半乳糖(1.2mg/30g体重)建立衰老模型,用药组分别用不同浓度的山药多糖灌胃,40天后测定小鼠血清中SOD活性,MDA含量及耐氧能力。结果:山药多糠能提高2月龄雄性小鼠血清超氧化物歧化酶(SOD)活性,降低小鼠血清丙二醛(MDA)的含量,提高小鼠的耐氧能力。结论:山药多糠具有抗氧化、抗哀老作用。  相似文献   

发达国家职工养老保险制度改革的展望及其对中国的启示     

罗钢 《深圳职业技术学院学报》2005,4(3):50-54

国家举办的社会统筹养老保险制度，因收入再分配和代际之间的收入转移以及养老福利的制度刚性问题，引起了世界许多经济学家的关注，特别是发达国家经济学家的关注。他们从制度设计和方案实施的不同视角，探讨养老保险制度的改革。本文在评析发达国家养老保险制度改革措施：养老保险制度改革的私有化、养老保险制度改革的市场化的基础上，总结出对中国养老保险制度改革的启示。  相似文献   

基于寿命特征的模糊遗传算法(英文)     

欧卫华  刘建国  孙勇 《怀化学院学报》2007,(4)

在知识发觉中遗传算法已经广泛应用于分类,模型选择和其它优化问题.但是它的行为和表现却直接受其输入参数值(如交叉概率和变异概率)的影响,不合理的参数设置通常会导致许多问题比如早熟问题.为此有的学者提出用自适应技术在算法过程中自适应调整这些参数,但这并未对遗传算法产生整体的改善,因为参数设置是依赖于具体问题的.提出了基于染色体个体寿命特征的遗传算法,用模糊逻辑控制器自适应调整交叉概率和变异概率.这个方法加强了遗传算法的全局搜索能力,很好的解决了早熟问题.将本算法和标准遗传算法及自适应遗传算法比较,仿真结果表明本算法在克服早熟问题上的明显优势.  相似文献   

浅析小水电发电机绝缘老化处理     

李秀 《杨凌职业技术学院学报》2011,10(4):55-57

针对小水电发电机组绝缘老化后的严重性,提出了一个快捷,经济,实用的处理办法。笔者通过对泾惠局渠首电站的机组绝缘老化处理实践证明,完全达到了预想的效果,可供相关灌区及小水电单位参考借鉴。  相似文献   

湖南人口老龄化问题研究   总被引：1，自引：0，他引：1  

匡爱民  李祖辉  李秀丽 《湘南学院学报》2011,32(2):79-83

从湖南人口老龄化现状出发,归纳总结湖南省人口老龄化的特征,并根据湖南省1990年-2006年人口统计数据对湖南人口发展趋势,尤其是老年人口发展趋势进行了预测,在此基础上,提出相应的政策建议,为湖南国民经济和社会发展"十二五"规划提供决策依据和参考.  相似文献   

电动车电瓶早衰原因及其预防措施     

赵正平  张媛 《巢湖学院学报》2012,(3):69-71

针对现有电动车电瓶早衰严重的问题,结合电瓶的工作原理,深入分析了电瓶早衰的原因,并提出了具体的预防措施。试验表明,这些措施能够较好地保证电瓶的使用寿命,预防早衰,具有很好的应用参考价值。  相似文献   

高填充碳酸钙/聚乙烯复合材料的老化试验研究     

苏晋升  张新星  王蒙亚  卢灿辉 《实验技术与管理》2012,29(6):55-58

采用锥形同向双螺杆挤出机制备了高填充量的碳酸钙/聚乙烯复合材料(碳酸钙质量分数为50%～75%),并系统研究了复合材料在氙灯下的老化行为。SEM形貌分析表明,在氙灯加速老化过程中,复合材料的多孔结构有助于裂纹的产生及聚乙烯链段间次价键力的削弱。GPC测试表明,老化后聚乙烯的重均分子量损失率达到80%以上,XPS研究证实老化后含氧基团含量增加。  相似文献   

Embodied life-long learning in nature,narratives and older bodies -‘quit or crash’     

Barbara Humberstone 《Journal of Adventure Education & Outdoor Learning》2019,19(2):101-110

ABSTRACT

This paper considers the significance of exploring the experiences and perspectives of older people who choose to participate in nature-based physical activities in evocative and imaginative ways. It highlights the need for research in outdoor studies to take seriously the turn to the body and the senses that is occurring in much social science and physical culture research, together with recognising the changing demographics in Western cultures which show a significant increase in the proportion of older people. The body has been separated from mind, emotions and feelings in much research in outdoor studies, and ageing studies and physical activity. For the most part, ageing studies have tended toward physiological perspectives with the dominance of medical research promoting biological empirical approaches to investigations. This paper considers theoretical perspectives which are embodied and emplaced and how such frameworks might contribute to the advancement of research on ageing and the outdoors. Sensory lived experiences are considered.  相似文献   

Towards a cross-cultural understanding of ageing and learning by senior adults in Hong Kong and Australia     

Maureen Tam 《International Journal of Lifelong Education》2017,36(5):565-577

Ageing and learning are value-laden concepts that are culturally relevant. Culture plays an important role in influencing what people think, resulting in different views and understandings by people from diverse cultural backgrounds. In the literature, there have been research and discussions relating culture with ageing and culture with learning to shed light on the value systems and predominant cultural values that have influenced the understanding of ageing and learning by people in different cultures. The aim of this paper is fourfold. First, it examines the concepts of ageing and learning and considers the role that culture plays in the understanding of these two constructs. Second, it draws on the predominant East–West cultural debate to shed light on the cultural values and views that have influenced the understanding and conceptualisation of ageing and learning. Third, limitations are identified for the East–West dichotomous view of ageing and learning using the Confucian perspective of learning to illustrate the inadequacies of the Eastern and Western ideas of learning, or lifelong learning, in particular. Finally, this paper draws on findings from a cross-cultural study to compare and contrast senior adults in Hong Kong and Australia, with regard to ageing and learning.  相似文献