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   23217篇
  免费   1286篇
各国政治   908篇
工人农民   1000篇
世界政治   1596篇
外交国际关系   728篇
法律   15926篇
中国共产党   2篇
中国政治   143篇
政治理论   4074篇
综合类   126篇
  2021年   117篇
  2020年   480篇
  2019年   523篇
  2018年   662篇
  2017年   700篇
  2016年   788篇
  2015年   578篇
  2014年   649篇
  2013年   2340篇
  2012年   613篇
  2011年   661篇
  2010年   660篇
  2009年   681篇
  2008年   664篇
  2007年   680篇
  2006年   696篇
  2005年   567篇
  2004年   576篇
  2003年   521篇
  2002年   536篇
  2001年   890篇
  2000年   809篇
  1999年   647篇
  1998年   311篇
  1997年   236篇
  1996年   267篇
  1995年   252篇
  1994年   235篇
  1993年   232篇
  1992年   430篇
  1991年   439篇
  1990年   406篇
  1989年   408篇
  1988年   419篇
  1987年   384篇
  1986年   431篇
  1985年   436篇
  1984年   341篇
  1983年   341篇
  1982年   259篇
  1981年   237篇
  1980年   203篇
  1979年   294篇
  1978年   176篇
  1977年   147篇
  1976年   126篇
  1975年   131篇
  1974年   176篇
  1973年   134篇
  1971年   111篇
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
241.
This paper highlights the difficulties and complexities of development assistance projects through an analysis of 2 Urban Functions in Rural Development projects conducted by the US Agency for International Development (AID) in Upper Volta and northern Cameroon in 1977-82. The general objectives of the Upper Volta project were to carry out urban function studies, develop a plan for strengthening the contributions of urban centers to rural development, develop a list of investment priorities for facilities and services, and increase the capacities of the Ministry in planning processes and methods. The 2-year project was hindered by a 1-year delay in initiating assistance due to difficulties in locating a contractor. In addition, the contractor and other team members felt there was little justification for studies of spatial organization in a country with so much evident need; rather, they focused on a small rural works program and establishment of effective local government, producing an inconsistency between team activities and the original project agreement. A request by the team to extend the project 1 year beyond its official completion date to compensate for early delays was rejected by USAID. Nonetheless, there was agreement that the project had a small positive impact in Upper Volta. Key lessons from Upper Volta were transferred to the Cameroon project. Although this project was judged to have achieved its objective of preparing a regional plan and of identifying programs for facilities, services, and small-scale enterprises, it was beset by problems of inexperience and technical underqualification of team members, poor communication, inconsistency of USAID guidelines, and methodological confusion. It is suggested that a central challenge for such programs is to create a body of qualified Americans who can work with their local counterparts in meeting the challenges of development. A measure of the success or failure of these projects should be the degree to which learning contributes to improved performance.  相似文献   
242.
243.
The issue of whether civilly committed patients should be extended the right to accept or refuse treatment has generated much controversy and litigation during the past 15 years. In general, the current rule is that in nonemergency situations, individuals who are competent to give informed consent to treatment should be extended the right to refuse it. Obviously, the manner in which this rule is implemented partly depends on how competence to consent to treatment is defined and measured. Most researchers have implicitly assumed that an understanding of treatment information is the sole criterion of competence. It is argued that such a definition may be incomplete and is in need of reexamination. Following a review and analysis of the relevant legal and psychological literature, a comprehensive construct of competency to consent to treatment is proposed and future directions for research are discussed.  相似文献   
244.
Physicians who defraud and abuse medical benefit programs provide a unique group of lawbreakers for scientific study. They could be considered to epitomize white collar criminals given their exceedingly high socioeconomic status and power as a professional group. Using official reports and documents, as well as interviews with enforcement and program personnel at both state and federal levels, this study examines the problem of physician fraud and abuse in Medicare and Medicaid. Major areas relevant to understanding this phenomenon and its control are presented and policy implications of present knowledge in the area are discussed.  相似文献   
245.
246.
247.
Spleen and portal lymphnode sections from 86 drug addicts submitted for medico-legal autopsy at the Institute of Forensic Medicine in Copenhagen in the year 1979 were studied together with tissue sections from 24 "normal" persons. In 70% of the drug addicts the spleen weight was more than 200 g, and in 71% portal lymphnode hyperplasia was found. Birefringent foreign material was found in spleen tissue of drug addicts in 72% and in portal lymphnode tissue in 44%. Signs of antigen stimulation in both spleen and portal lymphnode tissue evaluated by the number of germinal centre and plasma cells were found in more than 80% of the drug addicts compared with about 20% of the "normal" persons. The results were related to anamnestic information of duration of drug abuse, to the spleen weight, to the occurrence of birefringent material and to the liver changes. Examination of lysozyme and immunoglobulin containing cells using the indirect preoxidase technique was performed in a total of 72 cases of spleen tissue, 59 cases of portal lymphnode tissue from drug addicts, 24 cases of spleen tissue and 18 of portal lymphnode tissue from "normal" persons. Lysozyme, IgM and IgG containing cells were found significantly more often among drug addicts than "normal" persons. The results indicate that the splenomegalia and the portal lymphnode hyperplasia often found in drug addicts are caused by continuous antigen stimulation due to repeated injections of various antigens.  相似文献   
248.
249.
250.
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