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51.
Yao  L; Lee  JK 《Radiology》1989,172(2):513-514
Two sports-related knee injuries resulted in small fractures at the posteromedial corner of the tibial plateau. Magnetic resonance imaging demonstrated findings consistent with an avulsion injury at the semimembranosus insertion, as well as a similar pattern of internal derangement in both cases.  相似文献   
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Background  

Evidence is growing that the built environment has the potential to influence walking--both positively and negatively. However, uncertainty remains on the best approaches to representing the pedestrian environment in order to discern associations between walking and the environment. Research into the relationship between environment and walking is complex; challenges include choice of measures (objective and subjective), quality and availability of data, and methods for managing quantitative data through aggregation and weighting. In particular, little research has examined how to aggregate built environment data to best represent the neighborhood environments expected to influence residents' behavior. This study examined associations between walking and local pedestrian supports (as measured with an environmental audit), comparing the results of models using three different methods to aggregate and weight pedestrian features.  相似文献   
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This study, a focused community analysis, was conducted to determine the health needs and status of the aggregate of school-aged adolescents (13–18 years) using a method combining an epidemiologic approach with an ethnographic field method. Health was defined broadly, assumed to be interrelated with environmental, economic, social, educational, and cultural variables influencing adolescent life. The research involved five steps: collection of available secondary epidemiologic and census data; interviews with key informants, such as teachers, parents, school nurses, and other adults working with teenagers; participant observation and ethnographic interviews with primary informants, that is, teenagers from a variety of backgrounds; and finally, analysis and reporting of secondary and ethnographic data. Of the many themes generated in the data collection, four are reported here: lifestyle, health, pregnancy, and substance abuse. Findings included a typology of subgroups of the adolescent population that influenced lifestyles and led to different attitudes toward health, pregnancy, and substance abuse. The ethnographic approach facilitated an understanding of the health needs and attitudes of teenagers, implying a need for altered interventions and approaches by adults teaching and caring for them.  相似文献   
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PURPOSE: Arterial distensibility decreases with age. This decrease may be associated with the initiation and/or progression of hypertension and atherosclerosis and may be attenuated by positive lifestyle habits, including habitual physical activity. We tested the hypothesis that self-reported sport, leisure, and work physical activity is associated with greater arterial distensibility (i.e., carotid artery pulsatile diameter changes). METHODS: The Atherosclerosis Risk in Communities (ARIC) study assessed left common carotid arterial diameters and intimal-medial wall thickness (IMT) using B-mode ultrasound techniques, in 10,644 African-American and white men and women aged 45-64 yr and free of cardiovascular disease. RESULTS: Work activity, but not sports or leisure activity, was weakly associated with greater arterial distensibility in an ANCOVA model adjusted for blood pressure and other covariates (diastolic arterial diameter, pulse pressure, pulse pressure squared, age, race, sex, smoking, dietary fat intake, height, education, and clinical center) (P for linear trend = 0.03). Vigorous sports activity was weakly positively associated with arterial distensibility (arterial diameter change (mean +/- SE in mm) 0.42 +/- 0.004 vs 0.41 +/- 0.002 for the 12.7% of participants reporting any vs no vigorous activity, P = 0.02), and this association was not attenuated by adjustment for IMT, body mass index, low-density lipoprotein (LDL) cholesterol, high-density lipoprotein (HDL) cholesterol, or diabetes. Repeated analyses with traditional arterial stiffness indices showed similar findings for vigorous but not work activity. CONCLUSION: In contrast to several smaller studies, these findings do not support the hypothesis that habitual physical activity has a strong, consistent positive effect on arterial distensibility.  相似文献   
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目的:测定炎痛净乳膏中双氯芬酸钠和苯佐卡因的含量。方法:高效液想象以谱法,甲醇为提取溶剂,地西泮为内标,No-va-PakC18色谱柱,甲醇-水-冰醋酸(80:20:0.5)为流动相,检测波长为283nm。结果:双氯芬酸钠和苯佐卡因在5μg/ml-40μg/ml范围内,其浓度与峰面积均呈良好的线性关系(r=0.9999),平均回收率分别为101.0%,RSD=1.21%,99.8%,RSD=0.62%。结论:本法专属性强,操作简便,结果准确。  相似文献   
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