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排序方式: 共有927条查询结果,搜索用时 15 毫秒
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T Meier T Rosburg M Arnold I Kreitschmann-Andermahr H Sauer H Nowak H Witte 《Canadian Metallurgical Quarterly》1998,108(6):526-535
PURPOSES: To determine what factors affect medical expenditure for the aged insured by the National Health Insurance among secondary medical care areas. METHOD: The original data of municipalities were combined and converted into the data of secondary medical areas. The original data included medical expenditure of the aged in 1994, medical supply factors per 100,000 population (numbers of doctors, numbers of general beds in hospitals, numbers of clinics, etc.) and socio-economic factors (income, proportion of employees for three sectors of industries, population density, average size of family, etc.). Medical expenditures for inpatients and outpatients were used separately as independent variables. The medical supply and socio-economic factors have been used as dependent variables. Multiple regression models were applied to clarify the differences in the contributing factors between inpatient and outpatient. RESULTS: 1. The maximum inpatient and outpatient medical expenditures for the aged are respectively 4 times and 2.6 times more expensive than minimum expenditures among secondary medical care areas. 2. The numbers of beds, income per capita, numbers of doctor, average size of family, proportion of employees for third level industry and income accounted for 57.4% of variance in inpatient medical expenditure of the aged. 3. The proportion of employees for first level industry, the numbers of beds and average members of family accounted for 21.4% of variance in outpatient medical expenditure of the aged. 4. Medical expenditure for inpatients related with medical supply and socioeconomic factors differently from that of outpatients. 相似文献
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PURPOSE: To create a simple and reproducible model of chromic thrombosis for the evaluation of thrombolytic agents and devices. MATERIALS AND METHODS: A stenosis was created in the superficial femoral artery of domestic swine, and autologous blood clot was deposited above the stenosis. Follow-up last for up to 3 months. Degree of clot organization was determined at histologic examination. Two thrombolytic agents, urokinase and collagenase, were used to test this model. RESULTS: There was a 27% delayed recanalization rate with this model. At histologic examination, early thrombus organization was seen at the vessel periphery after 10 days. One-month-old thrombus was substantial but variable in amount. Three-month-old thrombus was completely organized. Neither urokinase nor collagenase proved effective against chronic clot in the doses and time course of this study. CONCLUSION: This simple method yields a chronic porcine clot in a reliable number of domestic swine in 1 month. 相似文献
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H. Nowak K. Kujawa R. Zadernowski B. Roczniak Halina Kozowska 《European Journal of Lipid Science and Technology》1992,94(4):149-152
Antioxidative and bactericidal properties were investigated in isolated and fractionated phenolic compounds of rapeseeds. Among the investigated groups of compounds (phenolic acids, sinapine and the products of its hydrolysis) phenolic acids, and especially sinapic acid, were found to be the most active. Due to valuable properties of these compounds they can be considered to be applied for food and fodder preserving. 相似文献
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BACKGROUND: Although many studies have examined the effects of antihypertensive agents on proteinuria and glomerular filtration rate in patients with kidney disease, many questions remain unresolved. These questions include whether the effects of agents differ, whether their effects are similar in diabetic and nondiabetic patients with renal disease, and whether the effects of any agents are independent of blood pressure reductions. METHODS: We conducted a meta-analysis of studies obtained with MEDLINE and bibliographies from comprehensive reviews but included only investigations with follow-up times of at least 6 months. We combined data (1) in an analysis of randomized controlled trials, (2) in a separate univariate analysis of controlled and uncontrolled trials, and (3) using weighted multiple linear regression. RESULTS: In 14 randomized controlled trials, angiotensin-converting enzyme inhibitors caused a greater decrease in proteinuria (pooled mean [95% confidence intervals], -0.51[-0.68 to -0.35], ln [treatment/control]), improvement in glomerular filtration rate (0.13 mL/min per month [0.10 to 0.16 mL/min per month]), and decline in mean arterial pressure (-4.0 mm Hg [-4.9 to -3.0 mm Hg]) compared with controls. In a multivariate analysis of controlled and uncontrolled trials, each 10-mm Hg reduction in blood pressure decreased proteinuria (regression coefficient [95% confidence interval] -0.14 [-0.22 to -0.06] ln [after/before]), but angiotensin-converting enzyme inhibitors (-0.45 [-0.58 to -0.32]) and nondihydropyridine calcium antagonists (-0.38 [-0.70 to -0.06]) were associated with additional declines in proteinuria that were independent of blood pressure changes and diabetes. Each 10-mm Hg reduction in blood pressure caused a relative improvement in glomerular filtration rate (0.18 mL/min per month [0.04 to 0.31 mL/min per month]), but among diabetic patients there was a tendency for dihydropyridine calcium antagonists to cause a relative reduction in glomerular filtration rate (-0.68 mL/min per month [-1.31 to -0.04 mL/min per month]). CONCLUSIONS: Long-term beneficial effects of antihypertensive agents on proteinuria and glomerular filtration rate are proportional to blood pressure reductions and are similar in diabetic and nondiabetic patients with renal disease. In addition, angiotensin-converting enzyme inhibitors, and possibly nondihydropyridine calcium antagonists, have additional beneficial effects on proteinuria that are independent of blood pressure reductions. 相似文献
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Bipolar meiotic spindle formation without chromatin 总被引:1,自引:0,他引:1
S Brunet Z Polanski MH Verlhac JZ Kubiak B Maro 《Canadian Metallurgical Quarterly》1998,8(22):1231-1234
Establishing a bipolar spindle is an early event of mitosis or meiosis. In somatic cells, the bipolarity of the spindle is predetermined by the presence of two centrosomes in prophase. Interactions between the microtubules nucleated by centrosomes and the chromosomal kinetochores enable the formation of the spindle. Non-specific chromatin is sufficient, however, to promote spindle assembly in Xenopus cell-free extracts that contain centrosomes [1,2]. The mouse oocyte represents an excellent model system in which to study the mechanism of meiotic spindle formation because of its size, transparency and slow development. These cells have no centrioles, and their multiple microtubule-organizing centers (MTOCs) are composed of foci of pericentriolar material [3,4]. The bipolarity of the meiotic spindle emerges from the reorganization of these randomly distributed MTOCs [4]. Regardless of the mechanisms involved in this reorganization, the chromosomes seem to have a major role during spindle formation in promoting microtubule polymerization and directing the appropriate rearrangement of MTOCs to form the two poles [5]. Here, we examined spindle formation in chromosome-free mouse oocyte fragments. We found that a bipolar spindle can form in vivo in the absence of any chromatin due to the establishment of interactions between microtubule asters that are progressively stabilized by an increase in the number of microtubules involved, demonstrating that spindle formation is an intrinsic property of the microtubule network. 相似文献