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961.
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A statewide program assessment was established to make positive change in physical education school programs in South Carolina. Reform efforts depend both on balancing accountability for change and teacher support for change (Odden &Anderson, 1986). The purpose of the study was to determine teacher perceptions of the South Carolina Physical Education Assessment Program and its effects across six related themes including: changes in teaching and learning, changes in curriculum and instruction, teacher awareness of the assessment program, teacher support for the program, work place conditions, and the advocacy role of the program. It was also the purpose of this study to determine if the survey responses were in any way related to teacher and school variables. The overall results of the study indicated positive change and support for the assessment program, supporting the viability of the standards, assessment, and accountability reform effort to positively impact physical education programs.  相似文献   
963.
Exercise has been shown to influence collagen synthesis and degradation. The aim of this study was to determine whether the stimulus for these changes is metabolic or mechanical. Eight healthy adults aged 22 +/- 4 years (mean +/- s) completed two exercise bouts-a 10 km road run and a deep water running session. Blood samples were collected before exercise and on days 1, 2, 3, 6 and 10 after exercise for measurement of creatine kinase activity, type IV collagen antigenicity, and concentrations of matrix metalloproteinase (MMP)- 9, tissue inhibitors of metalloproteinase (TIMP)- 1 and -2, and the MMP-2/TIMP-2 complex. Serum creatine kinase was elevated 24 h after the road run, but unchanged after the deep water running session. Serum collagen IV antigenicity decreased after both the road run and the deep water running session, suggesting suppressed type IV collagen synthesis in response to exercise, although serum MMPs and TIMPs remained unchanged after exercise. These results suggest that collagen IV synthesis is temporarily suppressed after exercise, irrespective of exercise type.  相似文献   
964.
The development of an improved type of contact screen is described. By using a transparent dye for the screen image, and also in some cases for a continuous-tone negative for use with the screen, contrast control is obtained with color filters, and increased resolution of detail results. Improved tone reproduction is incorporated in the gradation of the screen dots. The greatest improvement in quality is obtained in deep-etch offset printing, where it is convenient to make a highlight screen positive from a magenta negative by contact through an orange-red contact screen.  相似文献   
965.
Abstract

Evidence suggests that periods of heavy intense training can result in impaired immune cell function, and whether this leaves elite athletes at greater risk of infections and upper respiratory symptoms (URS) is still debated. There is some evidence that episodes of URS do cluster around important periods of competition and intense periods of training. Since reducing URS, primarily from an infectious origin, may have implications for performance, a large amount of research has focused on nutritional strategies to improve immune function at rest and in response to exercise. Although there is some convincing evidence that meeting requirements of high intakes in carbohydrate and protein and avoiding deficiencies in nutrients such as vitamin D and antioxidants is integral for optimal immune health, well-powered randomised controlled trials reporting improvements in URS beyond such intakes are lacking. Consequently, there is a need to first understand whether the nutritional practices adopted by elite athletes increases their risk of URS. Second, promising evidence in support of efficacy and mechanisms of immune-enhancing nutritional supplements (probiotics, bovine colostrum) on URS needs to be followed up with more randomised controlled trials in elite athletes with sufficient participant numbers and rigorous procedures with clinically relevant outcome measures of immunity.  相似文献   
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