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901.
It is known that an increased level of red blood cell 2,3-diphosphoglycerate (DPG) shifts the oxyhemoglobin dissociation curve to the right, thus allowing a greater unloading of oxygen at the tissue level. It has been hypothesized that phosphate might help increase VO2max by increasing 2,3-DPG level. Eight trained cyclists underwent three cycle ergometer tests (control, placebo, and experimental) to determine whether phosphate ingestion had any positive effect on VO2max, time to exhaustion, serum 2,3-DPG, and serum phosphate levels. We found no change between the control, placebo, or experimental conditions in pretest serum phosphate levels, but we did find increases in 2,3-DPG levels in the phosphate condition (p less than .05), which suggests that even a small amount of phosphate could increase levels of 2,3-DPG. We also found significant differences in VO2max between the control (p less than .05) and placebo (p less than .02) conditions and also in time to exhaustion between the three conditions (p less than .05). We suggest that phosphate may have an ergogenic effect, but clearly more work needs to be undertaken to ascertain the amount of phosphate required and the magnitude of the effect.  相似文献   
902.
The growing frustration of developing countries with their relatively slow rate of economic progress, their increasing dependence on imports of technology despite genuine efforts for endogenous developemt, and the flight of their skilled manpower for employment in developed countries have combined to focus attention of their educational planners on the ‘appropriateness’ of their engineering education programmes. Since technology is nation- and culture-specific, it is argued that all educational programmes in the field of engineering and technology should be specifically designed to meet the needs of the country concerned. Formulation of such programmes may, however, inhibit mobility of engineers across national boundaries, hamper transferof technology and decelerate global economic and technological development. The paper examines the observable differences in the characteristics of developing and developed countries, the technological framework and projections of economic growth of developing countries and the special features of the engineering educational system needed to respond to their needs. Implications of recent advances in information technology, biotechnology and manufacturing technology on engineering education planning are analysed. The compatibility of socially relevant engineering education with that of internationally comparable standards is examined in detail. It is shown that it is possible to develop programmes in developing countries which are intellectually challenging, meet international standards of achievement and at the same tiem equip students with competence in technology assessment, with awareness of pitfalls of technology transfer and with experience in use of technological solutions for current social and economic problems. It is argued that such programmes while essential for developing countries will be equally useful to developed countries and would accelerate international appreciation of problems of development. The reversal of brain-drain is proposed through the creation of challenging opportunities at home coupled with the utiltisation of intellectual and financial resources of emigré nationals abroad.  相似文献   
903.
904.
The experiences of medical students, residents, and faculty with a computerized literature searching system were evaluated. Third-year medical students, internal medicine and family practice residents, and full-time and voluntary faculty at one medical school had the opportunity to use a full-text and bibliographic medical literature retrieval system free of charge for an eleven-month period. Subjects conducted nearly nine thousand literature searches over a period of 942 system hours. Questionnaire data showed that participants could learn to use and would use an electronic information system, felt capable of using the system, utilized the system for a variety of purposes and in a number of different ways, and viewed the system as a valuable tool in searching the medical literature. The results are discussed in the context of the educational needs of the four user-groups and medical education planning by institutions.  相似文献   
905.
The purpose of this study was to determine how female marathon runners of varying standards differed in body composition and physique and in their training regimes, and secondly to develop predictors of distance running performance from the anthropometric and training variables. Female marathon runners (n = 36), all participants in a national 10 mile (16 km) road racing championship, were divided into three groups according to their best time for the 26.2 mile race. They were assessed for body composition and somatotype using anthropometric techniques and completed a questionnaire about their current training for the marathon. No difference was found between the groups of distance runners when measured for height, bone widths and circumferences. The three groups were found to have similar body weights of approximately 53 kg, a value which is much lower than the average for sedentary women, but which compares favourably with those from previous studies of female long distance runners. While all the runners had a lower per cent fat, as measured from skinfold thicknesses, than sedentary women, the elite runners were seen to have significantly lower values (P less than 0.05) than the other two groups. The difference in body fat was particularly reflected in the triceps skinfold value. There was also a tendency for the elite runners to be more ectomorphic and less endomorphic than the others. The better runners were seen, on the whole, to have been running longer, and to have more strenuous regimes, both in terms of intensity of training and distance run per week. Multiple regression and discriminant function analyses indicated that the number of training sessions per week and the number of years training were the best predictors of competitive performance at both 10 mile and marathon distances. They also indicated that a female long distance runner with a slim physique high in ectomorphy has the greatest potential for success.  相似文献   
906.
With the advent of Title IX, the proportion of female participants in interscholastic sport has risen sharply while the proportion of female coaches has dropped precipitously. This paper seeks to determine whether there are any differences in coaching philosophy by gender. Questionnaires were sent to the coaches of 600 high school girls' basketball teams selected randomly from the 48 contiguous states. There were 250 usable ones returned for a response rate of 42%. The questionnaires included items designed to assess the attitudes and behaviors of coaches in five areas of coaching philosophy: (1) the coach's role in the overall development of athletes; (2) conditions believed essential to maximize team performance; (3) team rules used; (4) use of sports aphorisms; and (5) expectations of athletes. Summing the findings, we found that in 83 of the 100 comparisons there were no statistical differences in the means of the male and female coaches. In the 17 instances where there were statistically significant differences, 14 times the female coaches were on the more traditional side. Several possible explanations for this interesting finding are discussed.  相似文献   
907.
农村建设是全国经济建设的重中之重,文章通过纵观农村经济现状,利用贝叶斯均衡博弈理论,对农村政策的效用进行分析,并对此提出了相关建议。  相似文献   
908.
909.
Editorial     
  相似文献   
910.
文章解读新时期社会主义中国人性发展与体育制度创新的科学内涵,探索人性发展与中国体育制度创新之间的相关性规律,管窥人学视野下中国体育制度创新的未来景图。  相似文献   
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