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51.
The mechanism of mass collaboration in risk management was studied during the Sichuan earthquake under a Web-based “PeopleFinder” project, where information is contributed and shared among mass contributors. The case study is provided by a great earthquake that happened in Wenchuan County, Sichuan Province, of southwestern China at 2:28 p.m. on May 12, 2008. We witnessed and experienced the rescue and relief efforts for the great earthquake. In this article, two fundamental frameworks are developed to study the mechanism of mass collaboration. Mass collaboration is proven to be effective in a big public crisis such as the Sichuan earthquake.  相似文献   
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After purification by buoyant density centrifugation in ethidium bromide - CsCl gradient and electrophoretic fractionation, the DNA fragments isolated from P. lividus egg nuclei incubated with micrococcal nuclease exhibit a typical oligomeric pattern. Analysis of chromatin samples digested to an increasing extent by micrococcal nuclease reveals that the structural organization of egg chromatin is heterogeneous, both in terms of repeat size and degree of sensitivity to nuclease attack. The nucleosomal repeats of P. lividus sperms and embryos up to the mesenchyme blastula stage have also been determined, for comparison.  相似文献   
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Pelvic exenteration offers the only possibility for cure in patients who have pelvic recurrence after receiving optimum amounts of irradiation. With improved radiotherapy techniques, the number of patients with isolated central failure is steadily diminishing, but there remains a significant number of patients with recurrent cancer of the cervix after radiation therapy for whom the procedure offers the only chance for life. Each patient must be assessed individually, with the risks of the procedure weighed against the possible benefits. Technical advances continue to reduce the operative mortality and ameliorate the postoperative morbidity associated with pelvic exenteration.  相似文献   
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The authors tested the influence of gentamicin, spectinomycin dihydrostreptomycin on the ADP and epinephrine in vitro induced platelet aggregation. Our aim was to demonstrate if platelet aggregation in vitro had some influences by antibiotics. A reduction in platelet aggregability, strictly dependent from the used antibiotic dose was observed. We have studied platelet function thanks to Born's method, adding to PRP gradual therapeutics doses of antibiotics. The results showed a reduction of platelet function which was dose-depended, and, particularly, gentamicin seemed to be the most effective among aminoglycosides. An interference between these drugs and the ADP and epinephrine binding to specific platelet receptor sites is proposed.  相似文献   
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