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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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A G Chuchalin V A Babushkina V Ia Arion R D Aspetov T B Sha?khinova 《Biulleten' eksperimental'no? biologii i meditsiny》1984,98(7):76-78
A study was made of the effect of T-activin on the biosynthesis of immune gamma-interferon. It was shown that in 27% of patients with chronic nonspecific pulmonary diseases, production of gamma-interferon by lymphocytes was substantially reduced during exacerbation of inflammatory process in the lungs. It was discovered that T-activin was not an interferon inductor but enhanced its synthesis in patients with a low capacity of producing immune interferon even at small doses of interferon inductor. The preparation does not produce any effect on this process in normal subjects and in patients showing the normal level of gamma-interferon. Thus T-activin can be used for stimulation of interferonogenesis. 相似文献
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Testosterone inhibits cAMP-induced de Novo synthesis of Leydig cell cytochrome P-450(17 alpha) by an androgen receptor-mediated mechanism 总被引:4,自引:0,他引:4
The regulation of the novo synthesis of the microsomal cytochrome P-450 enzyme, P-450(17 alpha), was studied in mouse Leydig cell cultures. Chronic treatment with 0.05 mM 8-Br-cAMP (cAMP) caused a time-dependent increase in 17 alpha-hydroxylase activity and in the amount of P-450(17 alpha), quantitated by immunoblotting. This increase in both activity and amount was enhanced by inhibiting testosterone production with aminoglutethimide, an inhibitor of cholesterol side-chain cleavage or SU 10603, an inhibitor of 17 alpha-hydroxylase. To examine the mechanism by which cAMP or cAMP plus inhibitors of testosterone production increased the activity and amount of P-450(17 alpha), changes in the rate of de novo synthesis were studied by measuring [35S]methionine incorporation into newly synthesized protein. Treatment with cAMP plus aminoglutethimide or SU 10603 caused a 2-fold or greater increase in the rate of de novo synthesis of P-450(17 alpha) compared to treatment with cAMP only. The addition of exogenous testosterone reversed this increase in the rate of synthesis, indicating that testosterone modulates the extent of cAMP-stimulated induction of P-450(17 alpha). This negative effect of testosterone could be mimicked by the addition of the androgen agonist, mibolerone, and prevented by the addition of the antiandrogen, hydroxyflutamide. Neither estradiol nor dexamethasone had any effect on the synthesis of P-450(17 alpha). Studies on the degradation of newly synthesized P-450(17 alpha) demonstrated that testosterone had no effect on the decay of P-450(17 alpha) during the first 24 h but caused a significant increase in the rate of decay between 24 and 48 h. These data indicate that testosterone produced during cAMP induction of P-450(17 alpha) negatively regulates the amount of this cytochrome P-450 enzyme by two distinct mechanisms: by repressing cAMP-induced synthesis of P-450(17 alpha) by an androgen receptor-mediated mechanism and by increasing the rate of degradation of P-450(17 alpha). A model is proposed for the regulation of P-450(17 alpha) in Leydig cells. 相似文献
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人体和动物模型的体表物理信息地形图的研究 总被引:1,自引:0,他引:1
对人体头面、躯干、四肢、耳廓各局部几十个及整个人体等体表部位正、背面等210个部位进行超微弱冷光和温度测量,输入电子计算机,经特殊的自编程序处理,获得十分清晰的,由3000多数据构成的各个局部或人体整体的冷光和温度地形图。 对家兔左、右耳廓、胸腹部、背部都分别观察32个部位的冷光与体表温度,经计算机分析处理,每观察区域获得约由2000个数据构成的精确的冷光、温度地形分市图。并可见不同生理、病理状态及不同病程家兔体表冷光、温度等地形图呈有规律的改变。 此外,我们还编制了以体表左右相应对称部位差值为分析数据进行地形图分析的程序,用以人体和动物体表物理信息对称规律的研究。 本工作以图形的形式显示物理参量在体表的广泛的分布规律,以揭示机体内部的不同生理、病理状态。本方法定位准确、直观醒目,为研究体表信息及机体生命活动规律提供了与逐点直接测量方法相互补充的有益的新手段。 相似文献
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We have used hydroelastic waves to treat the closed trauma of the soft tissue. The Shu Huo Jiu (S. H. J.) which is the Chinese traditional medicine alcohol, was used as the fluid medium for generating the pressure waves. The biomechanical model was established and analysed. Both animal and human tests have been made. A practical system was designed, constructed and clinically tested to treat the closed trauma, such as the bruise, contusion, sprain etc.. This system was found to be effective. 相似文献
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用数学方法推导出了自交作物群体遗传组成的分析公式。根据所推出的公式,可以计算出任何自交世代群体的基因型频率和同一表现型中各基因型的频率。对自交群体遗传组成的分析可用于质量性状的选择,确定选择时需要的有效群体大小和选出有效群体的大小,亦有助于确定选择的最佳世代。 相似文献