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   7615篇
  免费   258篇
各国政治   377篇
工人农民   278篇
世界政治   592篇
外交国际关系   294篇
法律   4442篇
中国政治   52篇
政治理论   1762篇
综合类   76篇
  2020年   107篇
  2019年   121篇
  2018年   178篇
  2017年   176篇
  2016年   181篇
  2015年   138篇
  2014年   151篇
  2013年   854篇
  2012年   175篇
  2011年   183篇
  2010年   176篇
  2009年   192篇
  2008年   194篇
  2007年   209篇
  2006年   209篇
  2005年   194篇
  2004年   169篇
  2003年   193篇
  2002年   172篇
  2001年   230篇
  2000年   194篇
  1999年   170篇
  1998年   113篇
  1997年   100篇
  1996年   77篇
  1995年   85篇
  1994年   82篇
  1993年   89篇
  1992年   125篇
  1991年   155篇
  1990年   133篇
  1989年   150篇
  1988年   139篇
  1987年   153篇
  1986年   144篇
  1985年   150篇
  1984年   139篇
  1983年   139篇
  1982年   105篇
  1981年   102篇
  1980年   91篇
  1979年   99篇
  1978年   77篇
  1977年   65篇
  1976年   70篇
  1975年   62篇
  1974年   70篇
  1973年   67篇
  1972年   56篇
  1969年   56篇
排序方式: 共有7873条查询结果,搜索用时 31 毫秒
981.
982.
983.
984.
985.
986.
987.
988.
Extravasation of plasma proteins in brain trauma   总被引:2,自引:0,他引:2  
The cellular distribution of extravasated plasma proteins in cortical contusions was studied with an immunoperoxidase method using polyclonal antibodies against human plasma albumin, alpha 1-acid glycoprotein, alpha 2-macroglobulin, alpha 1-antitrypsin, transferrin, hemopexin, haptoglobin, fibrinogen, fibronectin and immunoglobulin G. The material consisted of 24 human autopsy brains with a primary diagnosis of cerebral contusion due to blunt trauma. The time interval between injury and death ranged between minutes and 7 years. Immediately after the trauma, a complete breakdown of the blood-brain barrier (BBB) occurred with hemorrhage and extravasation of all types of plasma proteins. This was followed by spreading of edema fluid within the extracellular space in and around the wound. Uptake of extravasated protein by glial cells began on the 3rd day followed by proliferation of reactive astrocytes whose ample cytoplasm appeared to serve as a reservior for the extravasated plasma proteins. Within the reactive astrocytes, plasma proteins and S-100 protein had a similar and diffuse distribution in the immunostained sections. The plasma proteins once incorporated into the glial cells remained unchanged for several years with little sign of degradation. It is suggested that the extravasated plasma proteins subsequent to uptake and processing by the glial cells, may serve some important physiological function in wound healing.  相似文献   
989.
The attempt to transfer a technology from a publicly funded laboratory to a profit-oriented manufacturer can be a lengthy and complex process, involving several organizations and several key individuals within each organization. For example, a product technology transfer team may include the public lab itself, one or more end user organizations during product development and trial, a transfer agency, a public funding agency, the receptor manufacturer, and a private funding agency. Studies of such multi party transfers have suggested many factors that have contributed to their success or failure. We feel that most of these factors can be organized under the rubric of a more general theory of cascading commitment. Specifically, in this paper we propose that the likelihood of a transfer's success can be substantially affected by excellent management of the team building process by the public lab's R&D manager/director. Successful teams are built by gaining the commitment of appropriate individuals from appropriate organizations in a sequential cascading effect, by insightful and customized solicitation of each new team member to join at the appropriate stage of commercialization. To do this, the manager must be cognizant of, and individually appeal to, each new team member's perceptions of three sets of variables: evidence of the prior members' credibility, evidence of the prior members' commitment, and the set of personal benefits to be gained from participation.  相似文献   
990.
In this paper, we consider what may be done when researchers anticipate that in the implementation of field experiments, random assignment to experimental and control groups is likely to be flawed. We then reanalyze data from the Minneapolis Spouse Abuse Experiment in a manner that explicitly models violations of random assignment. As anticipated, we find far larger treatment effects than previously reported. The techniques developed should be useful in a wide variety of settings when random assignment is implemented imperfectly.  相似文献   
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