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81.
Objective: The purpose of the present study was to analyze whether improvements in fast walking speed induced by resistance training (RT) are associated with changes in body composition, muscle quality, and muscular strength in older women. Methods: Twenty-three healthy older women (69.6?±?6.4 years, 64.95?±?12.9?kg, 1.55?±?0.07?m, 27.06?±?4.6?kg/m²) performed a RT program for 8 weeks consisting of 8 exercises for the whole body, 3 sets of 10–15 repetitions maximum, 3 times a week. Anthropometric, body composition (fat-free mass [FFM], skeletal muscle mass [SMM], legs lean soft tissue [LLST], fat mass), knee extension muscular strength (KE1RM), muscle quality index (MQI [KE1RM/LLST]), and 10-meter walking test (10-MWT) were performed before and after the intervention. Results: Significant (P?<?.05) changes were observed from pre- to post-training for FFM (+1.6%), MQI (+7.2%), SMM (+2.4%), LLST (+1.8%), KE1RM (+8.6%), fat mass (?1.4%), and time to perform 10-MWT (?3.7%). The percentage change in 10-MWT was significantly associated with percentage change in MQI (r?=??0.46, P?=?.04) and KE1RM (r?=??0.45, P?=?.04), however not associated percentage of changes in SMM (r?=?0.01, P?=?.97), LLST (r?=??0.22, P?=?.33), and body fat (r?=?0.10, P?=?.66). Conclusion: We conclude that the improvement in the 10-MWT after an 8-week RT program is associated with increases in lower limb muscular strength and muscle quality, but not with muscle mass or body fat changes in older women.  相似文献   
82.
为探讨不同强度跑台运动对老年机体内血浆内皮素-1(ET-1)水平的影响,以18月龄大鼠为研究对象,随机分为4组:大强度运动组、中等强度运动组、小强度运动组、增龄对照组,另设3月龄对照组.运动组的运动方式为跑台运动,共训练6周,观察增龄和不同强度跑台运动对大鼠血浆ET-1及血清MDA、SOD水平的影响。结果显示:增龄大鼠血浆ET-1、血清MDA水平与青年对照组相比显著升高,而血清SOD水平显著下降。经过为期6周的跑台运动,中等强度运动组增龄大鼠血浆ET-1、血清MDA水平显著下降,SOD活性显著增强,而强度过大或过小的运动训练则对其无显著性影响。  相似文献   
83.
Emerging topic detection is a vital research area for researchers and scholars interested in searching for and tracking new research trends and topics. The current methods of text mining and data mining used for this purpose focus only on the frequency of which subjects are mentioned, and ignore the novelty of the subject which is also critical, but beyond the scope of a frequency study. This work tackles this inadequacy to propose a new set of indices for emerging topic detection. They are the novelty index (NI) and the published volume index (PVI). This new set of indices is created based on time, volume, frequency and represents a resolution to provide a more precise set of prediction indices. They are then utilized to determine the detection point (DP) of new emerging topics. Following the detection point, the intersection decides the worth of a new topic. The algorithms presented in this paper can be used to decide the novelty and life span of an emerging topic in a specific field. The entire comprehensive collection of the ACM Digital Library is examined in the experiments. The application of the NI and PVI gives a promising indication of emerging topics in conferences and journals.  相似文献   
84.
人口问题始终是制约一个国家、区域全面、协调、可持续发展的重大问题。河南省作为中国第一人口大省,其在人口数量、规模、结构、索质等方面存在着突出问题,也面临前所未有的复杂形势。在综合分析河南省经济社会发展中人口现状的基础上,总结了河南省现阶段存在的人口特征及人口问题,为解决河南省人口问题和制定人口政策,促使河南省由人口大省转化为人口强省提供了基础和依据。  相似文献   
85.
Evidence suggests that the deterioration of communication between the sympathetic nervous system and cardiovas-cular system always accompanies the aging of human and animals. Cardiac sympathetic norepinephrine (NE) transporter (NET) on presynaptic membrane is a predominant component to eliminate released NE in the synaptic cleff and maintains the sensitivity of the β-adrenergic receptor (β-AR). In the present study, we investigated NET and β1-AR mRNA levels and sympathetic nerve density in cardiac sympathetic ganglion and leff ventricular myocardium in 2- and 16-month-old rats with Northern blot analysis and immunohistochemistry. The expression levels of NET mRNA, NET protein and β1-AR mRNA in the ganglia or myocardia of 16-month-old rats were markedly reduced by 67%, 26%, and 43%, respectively, in comparison with those in 2-month-old rats. Our results also show that aging induces a strong decrease of the catecholaminergic nerve fiber density.  相似文献   
86.
以温州市图书馆为例,通过对老年分馆成立背景的分析和老年分馆成立后具体的服务和措施以及分馆成立后取得的效果的陈述,说明成立独立馆舍的老年分馆,是图书馆服务老年社会体系的重要途径。  相似文献   
87.
《文物保护研究》2013,58(1):33-54
Abstract

The final report on the Canadian Conservation Institute's poly(vinyl acetate) and acrylic adhesive research is given after 25–27 years of dark aging and 12–15 years of light aging. A total of 27 poly(vinyl acetate) and 25 acrylic adhesives were tested for pH, volatile emissions (mostly acetic acid), flexibility, strength, and yellowing after aging. In 1996, the work was first published after three to five years of aging data had accumulated. Measurements for pH, yellowing, strength, and flexibility were recently repeated again and these results are reported here. These new data points are reported to provide insight into the effect of these longer aging periods on the products included in the study. As well, the most stable (according to set criteria) poly(vinyl acetate) and acrylic adhesives tested are revealed, which, except for a few products, do not differ greatly from those reported in 1996.  相似文献   
88.
Analysis of twenty-six college and university libraries' monographic holdings in WorldCat shows that university libraries hold radically more rare titles and their collections are seven times larger than college libraries. Language and Literature (Library of Congress [LC] class P) accounts for 30% of university and 27% of college holdings. The number of books held declines and the number owned by only one library increases after the 2000 publication year. Since then, total library budgets have barely kept pace with inflation and book budgets have declined as a percentage of library expenditures. These changes align with current emphasis on priorities other than book collections.  相似文献   
89.
本文从骨代谢、线粒体功能变化、糖的跨膜转运和心理调节几方面论述了体育运动对衰老女性的作用,认为体育运动可增强骨的形成和矿化、战少骨破坏、延缓骨量丢失,增强线粒体功能,提高机体免疫力,加速糖代谢,改善衰老女性的心理健康水平,以战少衰老女性的身心疾病,提高生活质量。  相似文献   
90.
The circadian rhythm of human circulating lipid components was studied under nearnormal tropical conditions in 162 healthy volunteers (103 males and 59 females; 7 to 75 years of age). They followed a diurnal activity from about 06:00 to about 22:00 and nocturnal rest. These volunteers were divided into four groups: Group A (7–20 years), Group B (21–40 years), Group C (41–60 years) and Group D (61–75 years), comprising 42, 60, 35 and 25 participants, respectively. A marked circadian rhythm was demonstrated for each studied variable in each group by population-mean cosinor analysis (almost invariably p < 0.001). Furthermore, circadian rhythm characteristics were compared among the 4 groups by parameter tests and regressed as a function of age, separately for males and females. A second-order polynomial characterized the MESOR of HDL cholesterol, phospholipids and total lipids, as well as the 24-h amplitude of total cholesterol and phospholipids. The 24-h amplitude of total lipids decreased linearly with age. The 24-h acrophase of the oldest age group (Group D) was advanced in the case of total cholesterol, HDL cholesterol, and total lipids, whereas that of phospholipids was delayed. Mapping the circadian rhythm (an important component of the broader time structure or chronome, which includes a. o., trends with age and extra-circadian components) of lipid components is needed to explore their role in the aging process in health.  相似文献   
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