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171.
摘要:心血管疾病(CVD)一直是全世界最主要的死因。由于CVD等慢性疾病对健康的威胁越来越大,有必要开展生活方式干预项目以控制这些疾病的危险因素。本研究的目的是评估美国的重要慢病干预项目—HELPS治疗型生活方式改变(TLC)项目对减少CVD危险因素和其他慢性疾病的有效性。方法:140位大学教职工参加为期12周的HELPS TLC项目,干预前后用配对t检验对其体重、BMI、腰围(WC)、6分钟步行距离(6MWD)、空腹血脂和血糖进行测定和比较。结果:干预后6MWD显著增加,总胆固醇(TC)和WC显著下降。对“高危”参与者进一步分析显示:BMI(-1.5±0.5,-3.9%)、TC(- 22.8±4.0,-9.0%)、LDL(- 14.1±4.9,9.3%)和血糖(-6.9±2.2,-6.1%)均显著下降;男性腰围(-4.5±0.8,-10%)显著减小,女性未见显著改变(-1.5±0.5,-4.0%)。此外,体重的变化与TC(r=0.43)、LDL(r=0.35)和血糖(r=0.44)的变化均显著相关。结论:参加12周的生活方式干预项目可以使CVD危险因素减少,特别是在CVD“高危”个体中。HELPS TLC项目的远期效果还待进一步深入研究。  相似文献   
172.
In Western societies scientists are increasingly expected to seek media exposure and cooperate with industry. Little attention has been given to the way such expectations affect the role of scientific experts in society. To investigate scientists’ own perspectives on these issues eight exploratory, in-depth interviews were conducted in Denmark with reputable nutrition scientists. Additionally, eight interviews were held with ‘key informants’ from the field of nutrition policy. It was found that nutrition scientists experience two dilemmas: first, between their aspiration to make a collective impact on public health and the powerful incentives of each to appear frequently in the media with new messages; second, between their need to cooperate with the food industry for financial reasons and their fear that this may compromise their independence and scientific integrity. It is argued that the dilemmas identified in this study should be dealt with openly by the relevant groups of scientists.  相似文献   
173.
Nineteen elementary teachers were observed for the frequency with which they modeled self-praise for their students and taught their students to praise and evaluate themselves. Measures of student self-concept, anxiety, and achievement responsibility were taken at the end of the year. It was found that teacher modeling of self-praise correlated negatively with boys' selfconcept and positively with girls'. Teacher encouragement of students to praise other students correlated positively with boys' anxiety and negatively with girls'. Teacher modeling of self-praise and teacher encouragement of students to praise other students were the best predictors of self-concept.  相似文献   
174.
British conservation is respected around the world for its excellence, based on a tradition of caring for heritage material, backed up by high‐quality training and research. This paper charts the origins and development of the conservation profession in the United Kingdom and provides a comprehensive overview of the number, location and variety of conservation specialists currently working in the UK. It looks at those working in both the public and private sectors. The findings are based on a number of surveys conducted by the professional bodies and by government agencies such as the Museums & Galleries Commission (MGC). Most of the information relates only to museums, but the most recent survey of conservators by the MGC also looked at provision in libraries and archives.  相似文献   
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The aim of the present study was to examine the movement patterns, ball skills, and the impressions of Swedish elite football players during competitive games on artificial turf and natural grass. Time - motion analyses (36 observations) and technical analyses (16 team observations) were performed and 72 male and 21 female players completed a questionnaire. No differences were observed between artificial turf and natural grass in terms of total distance covered (mean 10.19 km, s = 0.19 vs. 10.33 km, s = 0.23), high-intensity running (1.86 km, s = 0.10 vs. 1.87 km, s = 0.14), number of sprints (21, s = 1 vs. 22, s = 2), standing tackles (10, s = 1 vs. 11, s = 1) or headers per game (8, s = 1 vs. 8, s = 1), whereas there were fewer sliding tackles (P < 0.05) on artificial turf than natural grass (2.1, s = 0.5 vs. 4.3, s = 0.6). There were more short passes (218, s = 14 vs. 167, s = 12) and midfield-to-midfield passes (148, s = 11 vs. 107, s = 8) (both P < 0.05) on artificial turf than natural grass. On a scale of 0-10, where 0 = "better than", 5 = "equal to", and 10 = "worse than", the male players reported a negative overall impression (8.3, s = 0.2), poorer ball control (7.3, s = 0.3), and greater physical effort (7.2, s = 0.2) on artificial turf than natural grass. In conclusion, the running activities and technical standard were similar during games on artificial turf and natural grass. However, fewer sliding tackles and more short passes were performed during games on artificial turf. The observed change in playing style could partly explain the male players' negative impression of artificial turf.  相似文献   
180.
The development of peak performances is a main research focus in sports science. It is unclear how many former top junior athletes achieve success in the elite class later. The aim of the present study was to examine the careers of athletes who participated in major junior or adult/elite cycling events using prospective and retrospective analysis of competition results. The official results of major junior (age < or = 18 years) and elite (age > 18 years) cycling races from 1980 to 2004 were analysed. Age-related aspects, career lengths, and success were compared between riders who presented results in both junior and elite races (JUNIOR ELITE) and riders who had no junior race results (ELITE ONLY). Altogether, 27,454 results of 8004 athletes from 108 countries were collected. We found that 29.4% of the elite athletes had participated in junior World Championships, and that 34% of the participants in junior World Championships later participated in major elite competitions. JUNIOR ELITE athletes are significantly more successful in several cycling disciplines and have their first and last elite result at a younger age than ELITE ONLY athletes. No difference was found in career lengths. The data presented here emphasize the importance of long-term training programmes in the development of peak performance in cycling.  相似文献   
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