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891.
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894.
The need for collaborative ventures in Europe has long been stressed in the editorial pages of this journal, and more than ten years ago (Endeavour, 28, 54, 1969) we gave strong support for a proposal to establish a European Laboratory of Molecular Biology. For this we then incurred some criticism, on the ground that such a laboratory would weaken national academic institutes striving to establish themselves in this rapidly developing field. Nevertheless, we continued to maintain (30, 2, '71) ‘the great political and scientific importance of this [concept]—and of other such collaborative enterprises—if Europe is to maintain the initiative in fields where the great institutions of the United States have established a dominant position.’ In the event, the Laboratory was established at Heidelberg in 1974, though not formally opened until 1978. The Director-General, Sir John Kendrew, here surveys the policy and achievements of this important new institute.  相似文献   
895.
The evidence from randomized controlled trials (RCTs) is widelyregarded as supplying the ‘gold standard’ in medicine—wemay sometimes have to settle for other forms of evidence, butthis is always epistemically second-best. But how well justifiedis the epistemic claim about the superiority of RCTs? This paperadds to my earlier (predominantly negative) analyses of theclaims produced in favour of the idea that randomization playsa uniquely privileged epistemic role, by closely inspectingthree related arguments from leading contributors to the burgeoningfield of probabilistic causality—Papineau, Cartwrightand Pearl. It concludes that none of these further argumentssupplies any practical reason for thinking of randomizationas having unique epistemic power.
1 Introduction
2 Why theissue is of great practical importance—the ECMOcase
3Papineau on the ‘virtues of randomization’
4 Cartwrighton causality and the ‘ideal’ randomizedexperiment
5 Pearl on randomization, nets and causes
6 Conclusion
  相似文献   
896.
Two different bond-graph schemes for the modeling of circulating fluids are discussed and compared. The first uses a heuristic approach wherein the flow path is broken into segments. Each segment has separate hydraulic and thermal submodels which are linked with active bonds. The model is general enough to handle natural convective flows, heat storage, conduction, forced convective heat transfer and heat energy sources. The second method, applicable to pumped flows, uses a modal analysis approach to derive state equations for the modal temperatures, the time varying coefficients of the spatially varying mode shapes in a separation of variables solution for the temperature partial differential equation. Two examples are worked to illustrate the models. Numerical simulation results are presented using the first method and a simple analytic solution given to illustrate the second.  相似文献   
897.
898.
The urinary excretion patterns of N-acetyl-β-D-glucosaminidase (NAG), alanine aminopeptidase (AAP) and protein/creatinine ratio (UP/UCR) were studied in 133 diabetic subjects under treatment, 7 patients with established diabetic nephropathy (DN) and 79 carefully selected (age-matched) healthy subjects. NAG, AAP and UP/UCR were highly elevated in DN, while in diabetics urinary NAG levels correlated well with the degree of long-term metabolic control indicated by glycosylated hemoglobin (GHB or Hba1). Both AAP and UP/UCR were found to be more sensitive than NAG, but less specific. Urinary NAG and AAP assays thus offer simple, sensitive and non-invasive techniques for prognostic indication of the onset of microangiopathic changes in long-term diabetic subjects.  相似文献   
899.
基于SSM分折的科研评价系统探讨   总被引:2,自引:0,他引:2  
科技评价体系是一个复杂的,多目标评价体系。当今科技评价已逐渐从强调科研产出,转向同时关注资源的使用效率,注重科技创新能力的提升和对国民经济发展的贡献。如何建立一个客观、公正、健全、规范的,且具备可操作性的科学评价体系引起了政府和科技界的广泛关注。本文以SSM系统分析为基础,从3E出发探讨了评价指标体系的构建和评价系统的设计。基于系统分析基础上形成的指标体系,既考虑了直接的产出,又分析了内部运行机制,形成的指标体系相对更全面、完整,在此基础上针对具体评价内容选择适宜的评价方法,可定量或定性,软硬结合,具有透明性和延展性,同时易与决策管理部门交流。  相似文献   
900.
Editorial     
Knowledge Management Research & Practice -  相似文献   
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