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991.
朱鸿召 《家具》2005,(6):66-66
中国家具在世界舞台上今天可以用一句话来概括,那就是:世界在期待着中国!  相似文献   
992.
朱斌 《印制电路信息》2006,(1):36-39,51
盲孔能够大大的增加板的密度,从而减小板面积。介绍了有关高厚径比盲孔电镀的有关工艺,从激光钻孔、金属化孔和电镀几个方面对孔径4mil以上的盲孔电镀进行了研究。  相似文献   
993.
断口分形研究与应用   总被引:1,自引:0,他引:1  
采用经典的Mandelbrot分形模型、Underwood修正分形模型和分维谱模型对三种球墨铸铁断口的分形特性进行了研究,并应用于铸态铁拉伸断口的断 断裂机制分析。  相似文献   
994.
Matrix metalloproteinases are thought to be key players in the remodelling activity of cells associated with both physiological and pathological processes. They share a relatively conserved structure with a number of identifiable modules linked to their specific functions. The structure of the individual domains of a number of matrix metalloproteinases have now been elucidated. Here we review these data in the light of complementary studies on the behaviour of these enzymes in biological systems. In particular we focus on the C-terminal hemopexin-like domain which has intriguingly specific roles in individual matrix metalloproteinases.  相似文献   
995.
Genotoxic effect and hepatic microsomal monooxygenase activities were assessed in mice treated with Acid Green 16 (single i.p. injection at dose 75 mg/kg) superimposed on prolonged ethanol consumption (10% solution in drinking water for 2-4 months). Treatment of mice with Acid Green 16 led to an increased frequency of micronucleated erythrocytes in bone marrow. In animals pretreated with ethanol the frequency of micronucleated erythrocytes, produced by Acid Green 16, was significantly higher. The changes in frequency of micronucleated erythrocytes were accompanied by the enhanced activity of microsomal monooxygenases manifested by higher activity of 7-ethoxycoumarin o-deethylase (the level of cytochrome P-450 was not altered). The obtained results showed that ethanol tended to increase the genotoxic effect of Acid Green 16. However, the slight inductive effect of ethanol on microsomal monooxygenases did not provide clear evidence that the genotoxic effect of Acid Green 16 was associated with ethanol stimulation of the metabolic activation of the dye in the liver.  相似文献   
996.
The authors tried to find the correlation between the occurrence of genital tract candidiasis in adolescents and some subjective and objective examination parameters. The highest correlation rates were found for pudendal pruritus, lower abdominal pains and early applied antibiotic therapy material: 188 adolescent girls.  相似文献   
997.
Reports an error in "Current issues relating to psychosocial job strain and cardiovascular disease research" by T?res Theorell and Robert A. Karasek (Journal of Occupational Health Psychology, 1996[Jan], Vol 1[1], 9-26). On p. 12, in the caption to Figure 2, the copyright statement is missing. The caption should have read "The environment, the worker, and illness: Dynamic associations linking environmental strain and learning to evolution of personality. From Healthy Work: Stress, Productivity, and the Reconstruction of Working Life (p. 99), by R. A. Karasek and T. Theorell, 1990, New York: Basic Books. Copyright 1990 by Basic Books. Used with permission." (The following abstract of the original article appeared in record 1996-04477-002.) Examines recent reviews of cardiovascular (CV) job strain (JS) research by P. L. Schnall and P. A. Landsbergis (1994) and T. S. Kristensen (see record 1995-39109-001), which conclude that JS as defined by the demand-control model (the combination of contributions of low job decision latitudes and high psychological job demands) is confirmed as a risk factor for CV mortality in a large majority of studies. Lack of social support at work appears to increase this risk. Several still-unresolved issues are discussed in light of recent research. Methodological issues related to the use of occupational & career aggregate estimates, use of standard scales for job analysis, and recall bias in issues of self-reporting are examined. Confounding factors and differential strengths of associations by subgroups in JS-CV disease analyses with respect to social class, gender, and working hours are addressed. A review of results of monitoring JS-blood pressure associations and associated methodological issues is provided. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
998.
The dependence between the activity parameters of muscarine antagonists in the prevention of haloperidol catalepsy in rats and those in tests characterizing the interaction of ligands and various subtypes of m-cholinoceptors was studied. It was established by constructing the mathematical dependence that blockade of m1-cholinoceptors increases, while that of m2-cholinoceptors reduces the antiparkinsonian activity of the drugs. The activity of the muscarine antagonist pentiphan in the prevention of haloperidol-induced catalepsy in rats exceeds the activity of such traditional antiparkinsonian drugs as cyclodol and amedin.  相似文献   
999.
1000.
本文首先介绍了计算几何的基本概念,论述了计算几何的四个基本问题,即几何搜索问题、相交问题、邻接问题及凸壳问题。然后重点分析了凸壳构造问题,介绍了其最佳串行算法、及相应的并行算法。接着对一些计算几何的串行及并行算法进行了分析比较。最后提出了笔者对新一代并行计算机系统上设计计算几何并行算法的看法。  相似文献   
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