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961.
962.
复杂性科学与现代城市管理 总被引:7,自引:0,他引:7
随着城市人口和规模的扩大,城市的结构、层次越来越复杂。城市的复杂性决定了城市管理工作的复杂性和艰巨性,它体现在问题的动态性以及城市管理各职能部门之间的相互影响和互动。本文介绍了复杂性科学,特别是开放的复杂巨系统理论及其方法论,在对现代城市及城市管理的复杂性分析基础上,提出现代城市及其管理是一类开放的复杂巨系统,应以复杂巨系统理论来指导城市管理工作,并分析了复杂性科学在城市管理中的应用,对现代城市管理有理论价值和现实意义。 相似文献
963.
通过耕地利用模式的遥感动态监测,认知丝绸之路核心带中亚五国与我国新疆地区的农业发展现状,同时结合两地水资源禀赋特征,总结耕地扩张过快、农业结构失衡是该地区农业发展存在的主要问题,也是区域生态环境恶化的主要根源。结合中亚与新疆水资源禀赋不足且空间分布不均、但天然草场丰富的特点,提出以流域为单元,水资源约束下的控制耕地规模、调整种植结构、积极发展高端畜牧业与精品瓜果业的发展思路,从而为"丝绸之路经济带"核心区的发展提供宝贵的水资源支撑。 相似文献
964.
知识管理系统绩效评价研究 总被引:5,自引:0,他引:5
如何测评知识管理系统具有重要的现实意义。在已有研究成果基础上,考虑到平衡计分卡的优点,结合CO-BIT框架建立了一个基于BSC的KMS有效性评价模型,该模型包含四个视角:知识管理能力、用户、学习与创新、战略与财务绩效。通过对四个视角的作用分析,构造了四个视角的评价矩阵和评价模型。 相似文献
965.
Induction of diabetes by Streptozotocin in rats 总被引:1,自引:0,他引:1
A. Akbarzadeh D. Norouzian M. R. Mehrabi Sh. Jamshidi A. Farhangi A. Allah Verdi S. M. A. Mofidian B. Lame Rad 《Indian journal of clinical biochemistry : IJCB》2007,22(2):60-64
The objective of this study is to induce experimental diabetes mellitus by Streptozotocin in normal adult Wistar rats via
comparison of changes in body weight, consumption of food and water, volume of urine and levels of glucose, insulin and C-peptide
in serum, between normal and diabetic rats. Intra-venous injection of 60mg/kg dose of Streptozotocin in adult wistar rats,
makes pancreas swell and at last causes degeneration in Langerhans islet beta cells and induces experimental diabetes mellitus
in the 2–4 days. Induction of experimental diabetes mellitus is indeed the first step in the plan of purification of pancreatic
Langerhans islet cells of normal rats for transplanting under the testis subcutaneous of experimentally induced diabetic rats.
Streptozotocin induces one type of diabetes which is similar to diabetes mellitus with non-ketosis hyperglycemia in some animal
species. For induction of experimental diabetes in male adult rats weighted 250–300 grams (75–90 days), 60mg/kg of Streptozotocin
was injected intravenously. Three days after degeneration of beta cells, diabetes was induced in all animals. The diabetic
and normal animals were kept in the metabolic cages separately and their body weight, consumption of food and water, urine
volume, the levels of serum glucose, insulin and C-peptide quantities in all animals were measured and then these quantities
were compared. For a microscopic study of degeneration of Langerhans islet beta cells of diabetic rats, sampling from pancreas
tissue of diabetic and normal rats, staining and comparison between them, were done. Induction of diabetes with Streptozotocin
decreases Nicotinamide-adenine dinucleotide (NAD) in pancreas islet beta cells and causes histopathological effects in beta
cells which probably intermediates induction of diabetes. In this study, we used Streptozotocin for our experiments in induction
of experimental diabetes mellitus. After Induction of diabetes, consumption of food and water, volume of urine and glucose
increased in the diabetic animals in comparison with normal animals, but the weight of body and the volume of insulin and
C-peptide decreased in the diabetic animals. Sampling and staining of pancreas tissue of diabetic and normal rats showed that
the Langerhans islet beta cells of diabetic rats have been clearly degenerated. In three days, Streptozotocin makes pancreas
swell and at last causes degeneration in Langerhans islet beta cells and induces experimental diabetes. It also changes normal
metabolism in diabetic rats in comparison with normal rats. Consumption of water and food, volume of urine, serum glucose
increases in diabetic animals in comparison with normal rats but the levels of serum insulin, C-peptide and body weight decreases. 相似文献
966.
967.
电子商务环境下,企业的知识产权管理呈现新的特色。文章首先分析了电子商务环境下企业知识产权管理中存在的问题,接着分析了它的新特点,最后从政府和企业两个角度提出了几点策略,以提高企业的自主创新能力,提升企业的竞争力,实现长久的发展。 相似文献
968.
Lakshmi Lavanya Reddy Swarup A. V. Shah Alpa J. Dherai Chandrashekhar K. Ponde Tester F. Ashavaid 《Indian journal of clinical biochemistry : IJCB》2016,31(1):87-92
Acute coronary syndrome (ACS) is a term for a range of clinical signs and symptoms suggestive of myocardial ischemia. It results in functional and structural changes and ultimately releasing protein from injured cardiomyocytes. These cardiac markers play a major role in diagnosis and prognosis of ACS. This study aims to assess the efficacy of heart type fatty acid binding protein (h-FABP) as a marker for ACS along with the routinely used hs-TropT. In our observational study, plasma h-FABP (cut-off 6.32 ng/ml) and routinely done hs-Trop T (cutoff 0.1 and 0.014 ng/ml) were estimated by immunometric laboratory assays in 88 patients with acute chest pain. Based on the clinical and laboratory test findings the patients were grouped into ACS (n = 41) and non-ACS (n = 47). The diagnostic sensitivity, specificity, NPV, PPV and ROC curve at 95 % CI were determined. Sensitivity of hs-TropT (0.1 ng/ml), hs-TropT (0.014 ng/ml) and h-FABP were 53, 86 and 78 % respectively and specificity for the same were 98, 73 and 70 % respectively. Sensitivity, specificity and NPV calculated for a cut-off combination of hs-TropT 0.014 ng/ml and h-FABP was 100, 51 and 100 % respectively. These results were substantiated by ROC analysis. Measurement of plasma h-FABP and hs-TropT together on admission appears to be more precise predictor of ACS rather than either hs-Trop T or h-FABP. 相似文献
969.
企业竞争情报部门设置模式研究 总被引:4,自引:1,他引:4
竞争情报是市场竞争激化和社会信息化高度发展的产物。随着社会经济环境的发展变化,竞争情报在企业发展战略中起着越来越重要的作用。本文介绍了传统等级式组织结构中竞争情报部门的建设及其优缺点,并阐述了现代新型组织结构下的协调总控——分布式设置模式和面向项目的虚拟竞争情报团队模式。 相似文献
970.
As Web-related techniques and equipment grow, the Internet has become popular as a major channel for providing a wide variety of information. However, users face the serious problem of information overload when acquiring increasing amounts of information from the Internet. This problem is one of the most important issues in providing information services to meet users’ requirements in an electronic commerce environment. In this paper, we propose an information push-delivery system, which applies fuzzy information retrieval and fuzzy similarity measurement to avoid the information overload problem. This proposed system is helpful for users to acquire suitable information from the Internet. An empirical investigation of the proposed system is implemented in this study. The results show that the degree of satisfaction for the received information for all participants was as high as 71%, indicating that the proposed system can effectively provide correct and interesting information for users. 相似文献