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21.
近年来,随着农村经济社会的快速发展,农村摩托车安全管理面临着新的问题:摩托车安全管理形势严峻,社会危害突出,交通需求矛盾突出,摩托车车主安全意识淡薄,社会执法守法环境较差。加强农村摩托车安全管理需要我们加强宣传教育,提高公民防范意识,实行综合治理,完善执法环境,科学管理,强化民本观念。  相似文献   
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A method has been developed on reverse phase high performance liquid chromatography for simultaneous determination of methyl, ethyl and isopropyl alcohols under refractive index detection using pure water as the mobile phase. A good separation has been achieved between these alcohols. Detector response was linear with a detection limit of 5 mg/100 ml. Recovery studies were performed by adding known amounts of methyl and ethyl alcohols to blood, lung and liver within the range 80–90%. The reproducibility of the results was always >90%. The quantitative distribution of methyl alcohol in postmortem body tissues and fluids has been reported in three cases of poisoning.  相似文献   
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Drawing on the strategic surprise, warning-response, and foreign policy literature, this article argues that the September 11 terror attacks should be regarded as a strategic surprise and examines a number of key factors that contributed to vulnerability and inhibited vigilance. Three broad explanatory "cuts" derived from the literature—psychological, bureau-organizational, and agenda-political—are deployed to sift through the rapidly expanding empirical record in an effort to shed light on the processes and contextual factors that left the United States vulnerable to the attacks. The article aims to improve our understanding of generic processes and practices that enhance or detract from vulnerability and vigilance.  相似文献   
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Decomposition studies were conducted using two carcasses of domestic pigs, Sus scrofa L., 8.4 kg and 15.1 kg in weight, to determine the effects of carcass size on the rate of decomposition, composition of the arthropod fauna, and succession patterns. A total of 46 arthropod taxa were recovered during this study. No size-related differences were observed between carcasses with respect to composition of the arthropod fauna or patterns of succession. A greater number of arthropods were observed attracted to the 15.1-kg carcass, and the rate of decomposition observed was more rapid for the 15.1-kg carcass than for the 8.4-kg carcass. Internal temperatures of the 8.4-kg carcass were more directly related to external ambient temperatures during the fresh and bloated stages of decomposition. During the decay stage, both carcasses generated internal temperatures significantly above ambient temperatures. Following this stage, internal temperatures fell to approximate ambient temperatures during the postdecay and remains stages.  相似文献   
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幼年牦牛松果体的光镜和电镜观察   总被引:1,自引:0,他引:1  
利用光镜和电镜技术对幼年牦牛松果体的组织形态结构特征进行了研究。结果表明,光镜下,幼年牦牛松果体由松果体细胞、少量的神经胶质细胞、毛细血管和神经等组成。电镜下,松果体细胞的电子致密度低,细胞质内含有丰富的线粒体、粗面内质网、滑面内质网、高尔基复合体、微管、微丝和核糖体,典型异质细胞器突触带呈球形,多位于质膜附近。神经胶质细胞内的线粒体丰富,胞体突起呈球形膨大伸入到松果体细胞之间。松果体细胞以及神经胶质细胞间均存在突触和连接复合体。牦牛松果体内的毛细血管为连续型,远腹侧血管周围可见色素细胞。  相似文献   
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The DNA commission of the International Society of Forensic Genetics (ISFG) was convened at the 21st congress of the International Society for Forensic Genetics held between 13 and 17 September in the Azores, Portugal. The purpose of the group was to agree on guidelines to encourage best practice that can be universally applied to assist with mixture interpretation. In addition the commission was tasked to provide guidance on low copy number (LCN) reporting. Our discussions have highlighted a significant need for continuing education and research into this area. We have attempted to present a consensus from experts but to be practical we do not claim to have conveyed a clear vision in every respect in this difficult subject. For this reason, we propose to allow a period of time for feedback and reflection by the scientific community. Then the DNA commission will meet again to consider further recommendations.  相似文献   
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This article examines constraints in development bureaucracies in intensifying the use of microcomputers as they move beyond processing applications to analysing applications. The work is based on the experience of several ministries of the Government of Kenya. Processing applications involve throughput of data and are relatively simple. Analysing applications, in contrast, are more complex and include data assembly, sensitivity analysis, and modelling. The article argues that processing applications are more compatible with the administrative cultures, bureaucratic functions, personnel skill levels and organizational structures of development bureaucracies. Analysing applications are less compatible because they require a level of training and motivation uncommon in development bureaucracies. Analysing applications are further thwarted by constraints in the supply of relevant information and the lack of demand for analysis by decision-makers. A four-cell matrix is developed which explains these constraints. The article concludes with several recommendations for encouraging microcomputer-based analysis, but cautions that processing applications will continue to dominate for the foreseeable future.  相似文献   
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