首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   500篇
  免费   18篇
各国政治   24篇
工人农民   18篇
世界政治   52篇
外交国际关系   22篇
法律   232篇
政治理论   169篇
综合类   1篇
  2023年   6篇
  2022年   4篇
  2021年   4篇
  2020年   5篇
  2019年   12篇
  2018年   26篇
  2017年   22篇
  2016年   23篇
  2015年   17篇
  2014年   14篇
  2013年   47篇
  2012年   25篇
  2011年   13篇
  2010年   16篇
  2009年   19篇
  2008年   31篇
  2007年   30篇
  2006年   31篇
  2005年   27篇
  2004年   24篇
  2003年   26篇
  2002年   22篇
  2001年   7篇
  2000年   11篇
  1999年   6篇
  1998年   2篇
  1997年   4篇
  1996年   2篇
  1995年   1篇
  1994年   2篇
  1993年   3篇
  1992年   3篇
  1991年   2篇
  1990年   4篇
  1989年   3篇
  1987年   1篇
  1986年   1篇
  1985年   4篇
  1984年   5篇
  1981年   1篇
  1980年   2篇
  1979年   3篇
  1977年   1篇
  1974年   2篇
  1973年   1篇
  1970年   2篇
  1963年   1篇
排序方式: 共有518条查询结果,搜索用时 15 毫秒
151.
Kalb C 《Newsweek》2002,140(14):59
  相似文献   
152.
Postmortem investigation is increasingly supported by Computed Tomography (CT) and Magnetic Resonance Imaging (MRI). This led to the idea to implement a noninvasive or minimally invasive autopsy technique. Therefore, a minimally invasive angiography technique becomes necessary, in order to support the vascular cross section diagnostic. Preliminary experiments investigating different contrast agents for CT and MRI and their postmortem applicability have been performed using an ex-vivo porcine coronary model. MSCT and MRI angiography was performed in the porcine model. Three human corpses were investigated using minimally invasive MSCT angiography. Via the right femoral artery a plastic tube was advanced into the aortic arch. Using a flow adjustable pump the radiopaque contrast agent meglumine-ioxithalamate was injected. Subsequent MSCT scanning provided an excellent anatomic visualization of the human arterial system including intracranial and coronary arteries. Vascular pathologies such as calcification, stenosis and injury were detected. Limitations of the introduced approach are cases of major vessel injury and cases that show an advanced stage of decay.  相似文献   
153.
Wallis C 《Time》2005,165(9):46-50, 52, 55 passim
  相似文献   
154.
155.
Cowley G  Kalb C 《Newsweek》2005,146(8):42-49
  相似文献   
156.
Kalb C 《Newsweek》2005,145(9):44-53
  相似文献   
157.
158.
The development of numerical human models is a topic of current interdisciplinary research. In the field of automotive safety these models can be applied for the optimization of protection systems. In forensic research human models can be used for the investigation of injury mechanisms and for the prediction and reproduction of injury patterns. However, up to now human models have been validated on the basis of PMHS tests without considering the effects of muscle activity. This paper shows two experimental volunteer test set-ups for the generation of experimental validation data. In a pendulum set-up the influence of muscle activity on the human kinematics was investigated. A drop test set-up was developed for the analysis of the effects of muscle activity on impact response characteristics of muscle tissue. Experimental results, presented in this paper, can be used for the validation and optimization of active numerical human models.  相似文献   
159.
This paper seeks to contribute to the growing literature on the entrepreneurial university by mapping knowledge exchange relationships of entrepreneurial faculty in a comprehensive manner and also capturing faculty attitudes towards measures taken by the university administration to promote entrepreneurship. We report on an exploratory study of Sussex University, a medium-sized, research-oriented university, which launched technology transfer activities in the mid-1990s. Our results show that, in spite of a comparatively late start, a considerable number of researchers engage in knowledge exchange processes with industry and other non-academic partners. We present evidence that suggests faculty in the social sciences and humanities as well as natural sciences and engineering maintain links to industrial partners, including multinational corporations. Furthermore, our observations indicate that schools differ in the way their faculty engage in university–industry collaborations. Further differences can be observed with respect to faculty attitudes towards technology transfer and awareness of the university’s respective codes of practice.
Arianna MartinelliEmail:
  相似文献   
160.
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号