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81.
A review of the use of prophylactic knee braces in football   总被引:1,自引:0,他引:1  
A review of nine studies of prophylactic knee braces worn by players in American tackle football lends some support for the use of double-hinged braces at the high-school level. Evidence for their use at the college level seems less persuasive. Caution should be exercised in interpreting these studies owing to the probable presence of bias and confounding variables and to difficulty in generalizing results beyond the study populations. The two studies that assigned braces randomly found lower injury rates for knees and knee ligaments among high-school and high-school size players. Conversely, a large, multiteam collegiate study found a significantly higher rate of knee injuries among brace users, a difference that remained when controlled for position, skill, and previous injury.  相似文献   
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OBJECT: The goal of this study is to report the incidence and clinical evolution of neurological deficits in patients who underwent resection of gliomas confined to the parietal lobe. METHODS: Patient demographics, findings of serial neurological examinations, tumor location and neuroimaging characteristics, extent of resection, and surgical outcomes were tabulated by reviewing inpatient and office records, as well as all pre- and postoperative magnetic resonance (MR) images obtained in 28 consecutive patients who underwent resection of a glial neoplasm found on imaging studies to be confined to the parietal lobe. Neurological deficits were correlated with hemispheric dominance, location of the lesion within the superior or inferior parietal lobules, subcortical extension, and involvement of the postcentral gyms. The tumors were located in the dominant hemisphere in 18 patients (64%); had a mean diameter of 39 mm (range 14-69 mm); were isolated to the superior parietal lobule in six patients (21%) and to the inferior parietal lobule in eight patients (29%); and involved both lobules in 14 patients (50%). Gross-total resection, documented by MR imaging, was achieved in 24 patients (86%). Postoperatively, nine patients (32%) experienced new neurological deficits, whereas seven (25%) had an improvement in their preoperative deficit. A correlation was noted between larger tumors and the presence of neurological deficits both before and after resection. Postoperatively higher-level (association) parietal deficits were noted only in patients with tumors involving both the superior and inferior parietal lobules in the dominant hemisphere. At the 3-month follow-up examination, five of nine new postoperative deficits had resolved. CONCLUSIONS: Neurological deterioration and improvement occur after resection of parietal lobe gliomas. Parietal lobe association deficits, specifically the components of Gerstmann syndrome, are mostly associated with large tumors that involve both the superior and inferior parietal lobules of the dominant hemisphere. New hemineglect or sensory extinction was not noted in any patient following resection of lesions located in the nondominant hemisphere. Nevertheless, primary parietal lobe deficits (for example, a visual field loss or cortical sensory syndrome) occurred in patients regardless of hemispheric dominance.  相似文献   
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The effects of centrally injected bombesin on central and peripheral stimulated gastric contractility were investigated in fasted urethane-anesthetized rats. Miniature strain gauge force transducers were acutely implanted on the corpus of the stomach and gastric contractility was analyzed by computer. Intracisternal injection of the stable thyrotropin-releasing hormone (TRH)-analog RX 77368 (77 pmol) induced a stimulation of gastric contractility for 40 min. Intracisternal injection of bombesin (62-620 pmol) followed 30 min later by that of RX 77368 resulted in a dose-related inhibition of the TRH-analog-induced gastric contractility. Intracisternal injection of bombesin (620 pmol) did not modify gastric contractility stimulated by intravenous carbachol. Stimulation of gastric contractility induced by TRH-analog microinjected into the dorsal vagal complex (DVC) was dose-related suppressed by concomitant injections of bombesin (6.2-620 pmol). Neither bombesin alone (6.2 pmol) nor vehicle modified basal gastric contractility. These results demonstrate that bombesin acts within the brain to inhibit vagally stimulated gastric contractility and that the DVC is a sensitive site for bombesin inhibitory action. These findings suggest a possible interaction between TRH and bombesin in the central vagal regulation of gastric contractility.  相似文献   
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用气相色谱研究抗氧化剂对膜脂肪酸的保护作用   总被引:3,自引:0,他引:3  
卢基贵  王伟  陈文为 《药学学报》1991,26(6):406-410
本文应用气相色谱技术直接测定三种生物膜(人红细胞膜,人血小板膜和鼠肝线粒体膜)多不饱和脂肪酸的含量变化,检测脂质过氧化程度。实验证实几种多羟酚类化合物(儿茶精,阿魏酸钠和没食子酸及其衍生物)不同程度地抑制(OH)诱导的脂质过氧化反应,并呈量效和构效关系。这类抗氧化剂对保护生物膜的结构与功能是有益的。  相似文献   
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本对医学院校学生就全科医生有关问题给于相应的答复,其中还包括自1997年以来由美国全科医学会举办的学生代表大会上所提出的一些问题,例如:什么是全科医生?全科医生的行业范围是什么?全科医生的工作,生活及收入情况如何等等问题。(Am.Fam.Physician1990.60:167-174)。  相似文献   
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