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101.
背景: 前期研究表明广西18~22岁少数民族学生体质量偏轻。 目的:拟进一步了解广西2645名少数民族学生体型及体质健康状况,寻找影响的关联因子。 设计、时间及地点:追踪调查,于2004-12/2007-12在广西民族大学完成。 对象:广西民族大学2003/2005三次体质健康测试的全体学生2 645人。男1 337人,女1308人,年龄为18~20岁,共15个民族。 方法:根据2003年教育部、体育总局《学生体质健康标准(试行方案)》和实施方法分为形态指标、技能指标和身体素质指标3大类。对2 645名少数民族身体机能与体质量指数变化的跟踪调查。 主要观察指标:身高、体质量、肺活量、立定跳远、坐位体前屈、体质量指数。 结果:①广西民族大学2003级学生大学3年期间男生身高、体质量增长率比全国同期多2.45%,身体形态发育正处于高峰期,女生成偏瘦型体型,身体形态发育情况总体欠佳。②男女学生在刚入校时肺活量机能较差,远远低于同期全国平均水平。3年后男生肺活量增长率为11.55%、女生肺活量增长率为27.72%,分别高于全国同期肺活量增长率。③坐位体前屈机能高于同期全国平均水平,男生呈逐年上升趋势,同期全国男性呈下降趋势;同期全国乡村女生均呈逐年上升趋势。④立定跳远机能提高较大,3年后增长率为18.15%,明显高于全国同期立定跳远增长率水平的2.61%。女生立定跳远机能总体不如全国同期水平。⑤体质量指数总体与同期全国乡村男女学生体质量指数比较稍低一些(P < 0.01)。 结论:2 645名少数民族学生发育正处于高峰期;肺活量机能不及全国同期平均水平。男女体质量指数分布有所不同,体质量偏轻者女生多于男生,表明学生营养状况总体欠佳。  相似文献   
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The purpose of this study was to evaluate a single-session peer-led safer sex intervention, based on the Information-Motivation-Behavioral Skills theoretical model, for college students residing in campus residence halls. Participants (N = 108) were assigned to either an hour long control or 5-module intervention session. Compared to the control condition, the intervention increased participants’ information and women’s subjective norms about preventative behavior. Both the control and intervention sessions increased intentions to perform preventative behaviors (e.g., keep condoms available). These preliminary results suggest that this intervention is promising for increasing constructs associated with safer sexual behavior and could easily be implemented by residence hall staff.  相似文献   
104.
The Institute of Medicine distinguishes between programs based on who is targeted: the entire population (universal), those at risk (selective), or persons exhibiting the early stages of use or related problem behavior (indicated). Evaluations suggest that although universal programs can be effective in reducing and preventing substance use, selective and indicated programs are both more effective and have greater cost-benefit ratios. This paper tests these assumptions by comparing the impact of these program types in reducing and preventing substance use at the individual level (i.e., those exposed to intervention services) and in the population (i.e., those exposed and not exposed to intervention services). A meta-analysis was performed on 43 studies of 25 programs to examine program comparability across IOM categories. When examining unadjusted effect sizes at the individual level, universal programs were modestly more successful in reducing tobacco use, but selective and indicated programs were modestly more successful in reducing alcohol and marijuana use. When adjusted to the population level, the average effect sizes for selective and indicated programs were reduced by approximately half. At the population level, universal programs were more successful in reducing tobacco and marijuana use and selective and indicated programs were more successful in reducing alcohol use. Editors’ Strategic Implications: The authors’ focus on the public health value of a prevention strategy is compelling and provides a model for analyses of other strategies and content areas.  相似文献   
105.
Purpose  There has been increasing interest in the occupational health of workers in small enterprises, especially in developing countries. This study examines the association between psychosocial job characteristics and fatigue, and attempts to identify risk factors for fatigue among workers of small enterprises in southern Taiwan. Methods  A structured questionnaire was administered to workers receiving regular health examinations between August 2005 and January 2006. The questionnaire collected demographic information and data on working conditions, personal health status and life styles. It also collected information on psychosocial job characteristics, fatigue and psychological distress using three instruments. Results  A total of 647 workers with mean age of 43.7 were completed. Probable fatigue was found in 34.6% of the sample. Fatigue was found by multiple logistic regressions to be associated with the lack of exercise, working in shifts, depression score and lack of social support at workplace. Conclusions  This study found associations between life style, psychosocial job characteristics and fatigue. Because the high prevalence of probable fatigue was found in such small enterprises, the authors suggest that a short interview with some quick questionnaires in health checkup for these small enterprise workers are helpful to early detect psychosocial and fatigue problems.  相似文献   
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Surrounding bovine chromaffin cells by a semipermeable membrane may protect the transplanted cells from a host immune response and shield them from the inflammatory process resulting from the surgical trauma. Encapsulation of the chromaffin cells was achieved by inter-facial adsorption of a polycation on a polyanionic colloid matrix in which the chromaffin cells were entrapped. Basal and potassium-evoked release of catecholamines from encapsulated bovine chromaffin cells was analyzed over a 4-week period in vitro. Norepinephrine and dopamine release remained constant over time whereas epinephrine release significantly decreased. The chromaffin cells also retained the capacity for depolarization-elicited catecholamine release 4 weeks following the encapsulation procedure. Morphological analysis revealed the presence of intact chromaffin cells with well-preserved secretory granules. Striatial implantation of chromaffin cell-loaded capsules significantly reduced apomorphine-induced rotation compared to empty polymer capsules in animals lesioned with 6-hydroxydopamne frr at least 4 weeks. Intact chromaffin cells expressing tyrosine hydroxylase and dopamine-β-hydroxylase were observed in all capsules implanted in the striatum for 4 weeks. The assessment of the clinical potential of transplanting encapsulated adrenal chromaffin cells of either allo- or xenogeneic origin for Parkinson's disease will require long-term behavioral studies. The present study suggests, however, that the polymer encapsulation procedure may offer an alternative to adrenal autografts as a source of dopaminergic tissue.  相似文献   
108.
Four cases of cervical vertebral artery (VA) dissection are reported. In three patients VA dissection was associated with neck trauma. All patients were young or middle-aged (range 27 to 49 years). In two there was a history of migraine. Pain preceded neurological symptoms from hours to six weeks. Three patients had neurological deficits including elements of the lateral medullary syndrome, and one experienced recurrent transient ischaemic attacks in the vertebrobasilar territory. Angiographic findings included irregular stenosis, occlusion and pseudoaneurysm; in two patients VA abnormalities were bilateral. All patients were treated with anticoagulants and improved. In a review of 28 cases with traumatic dissection and 29 cases with spontaneous dissection of the VA reported in the literature, distinct clinical and angiographic features emerge. Aetiology remains obscure in most cases of spontaneous dissection and management is still controversial.  相似文献   
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The human prostatic urethra has been investigated by means of scanning electron microscopy. On the posterior wall of the urethra, the seminal colliculus with the orifices of the ejaculatory ducts is clearly detectable. The upper portion of the prostatic urethra shows a typical transitional epithelium with large superficial cells of a ruffled appearance. In the lower portion of the organ (underneath the openings of the ejaculatory ducts), the apical pattern of the cells varies considerably. Four main aspects are recognizable: apices provided with microvilli, dome-shaped apices with an almost smooth surface, large apices with labyrinthic microplicae and ciliated apices. Also, apices showing intermediate characteristics can be noted. The functional significance of the morphological patterns as well as the possibility of a transition among the various types of surface structures are discussed.  相似文献   
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