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101.
Caloric restriction (CR) has been observed to retard aging processes and extend the maximum life span in rodents. In an effort to evaluate the effect of this nutritional intervention on physiologic variables in higher species, several nonhuman primate trials are ongoing. In particular, a study evaluating the independent effect of CR on the extent of atherosclerosis was initiated in 1993 in 32 adult cynomolgus monkeys. Therefore, the trial was designed to achieve identical cholesterol intake after animals were randomized to a control group or a calorie-restricted group (30% reduction from baseline caloric intake). The animals were routinely evaluated for glycated proteins, plasma insulin and glucose levels, insulin sensitivity, and specific measures for abdominal fat distribution by CT scans over a 4-year interval. The results from 4 years of intervention demonstrate that CR improves cardiovascular risk factors (such as visceral fat accumulation) and improves insulin sensitivity. In contrast to other primate studies with normolipidemic animals, CR had no independent effects on plasma lipid levels and composition in the presence of equivalent amounts of dietary cholesterol intake. Preliminary analysis of atherosclerotic lesion extent in the abdominal aorta has failed to demonstrate differences between control animals and CR animals. Follow- up studies are being conducted to determine the effect of CR on atherosclerosis extent in coronary and carotid arteries.   相似文献   
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K-Ⅱ系k阿片激动剂U-50488的同类物。通过部分离体和整体实验比较了K-Ⅱ与U-50488的药理作用。实验发现,K-Ⅱ抑制电刺激兔输精管收缩的IC50值为0.42 nmol/L,U-50488为26.5 nmol/L;K-Ⅱ抑制小鼠运动功能(横筛法)的ED50值为1.7 mg/g,U-50488为15.3 mg/kg;K-Ⅱ的小鼠LD50值为152.5 mg/kg,U-50488为118.4 mg/g;K-Ⅱ明显降低小鼠自发活动的作用比U-50488强5倍。结果表明,K-Ⅱ是一个药理作用较U-50488强的k受体激动剂。  相似文献   
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The diagnostic accuracy of the following methods of analysing exercise tests were evaluated: (a) the cumulative area of ST segment depression during exercise normalised for workload and heart rate (exercise score); (b) discriminant analysis of electrocardiographic exercise variables, workload, and symptoms; and (c) ST segment amplitude changes during exercise adjusted for heart rate. Three hundred and forty five men without a history of myocardial infarction were studied. One hundred and twenty three were apparently healthy. Less than half (170) had coronary artery disease. All had a normal electrocardiogram at rest. A Frank lead electrocardiogram was computer processed during symptom limited bicycle ergometry. The accuracy of the exercise score (a) was low (sensitivity 67%, specificity 90%). Discriminant analysis (b) and ST segment amplitude changes adjusted for heart rate (c) had excellent diagnostic characteristics (sensitivity 80%, specificity 90%), which were little affected by concomitant use of beta blockers. Both methods seem well suited for diagnostic application in clinical practice.  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   
108.
We describe a large family with a primary focal dystonia from a small Dutch village on a former island. Twenty‐four individuals spanning three generations were examined by two movement‐disorder neurologists. Two other movement‐disorder neurologists evaluated the videos independently. Subjects were classified as “affected,” “possibly affected,” or “not affected.” A diagnosis was defined if all the neurologists agreed on the definition. Eight definitely affected and four possibly affected subjects were detected. Clinical presentation consisted of mild cranio‐cervical‐brachial dystonia. Mean age at onset was 45.5 years (range, 39–56). Mean BFMDRS motor score was 4.4 (range, 1–8). Mean TWSTRS score (part I) was 11.3 (range, 8–23). Mutations in DYT1 gene and in the ε‐sarcoglycan (SGCE) genes were not detected. We could not find linkage to the dominant DYT6, DYT7, DYT13, or the recessive DYT16 loci. The identification and accurate clinical evaluation of large dystonia families not linked to known genes is crucial for further advancement in molecular genetic characterization of focal dystonia. © 2008 Movement Disorder Society  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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