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   8218篇
  免费   548篇
各国政治   440篇
工人农民   276篇
世界政治   625篇
外交国际关系   314篇
法律   5613篇
中国政治   34篇
政治理论   1427篇
综合类   37篇
  2023年   58篇
  2021年   61篇
  2020年   195篇
  2019年   219篇
  2018年   252篇
  2017年   270篇
  2016年   274篇
  2015年   237篇
  2014年   239篇
  2013年   915篇
  2012年   208篇
  2011年   210篇
  2010年   225篇
  2009年   243篇
  2008年   195篇
  2007年   195篇
  2006年   203篇
  2005年   186篇
  2004年   207篇
  2003年   189篇
  2002年   163篇
  2001年   334篇
  2000年   283篇
  1999年   233篇
  1998年   105篇
  1997年   69篇
  1996年   73篇
  1995年   84篇
  1994年   96篇
  1993年   95篇
  1992年   159篇
  1991年   164篇
  1990年   150篇
  1989年   160篇
  1988年   127篇
  1987年   143篇
  1986年   127篇
  1985年   134篇
  1984年   103篇
  1983年   118篇
  1982年   86篇
  1981年   79篇
  1980年   59篇
  1979年   114篇
  1978年   75篇
  1977年   60篇
  1976年   50篇
  1975年   48篇
  1974年   55篇
  1973年   62篇
排序方式: 共有8766条查询结果,搜索用时 15 毫秒
11.
12.
13.
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   
14.
15.
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   
16.
17.
18.
19.
20.
A minisatellite probe, MZ 1.3, detecting hypervariable fragment patterns was isolated from a human genomic library. A repetitive sequence of 27 bp length was identified which is contained in the probe approx. 40 times. The MZ 1.3 repeat shows variable homology of 53-73% to the repetitive sequence of the protein III gene of the bacteriophage M13 genome. Polymorphic restriction fragment patterns were found with MZ 1.3 using the enzymes Hinf I, BstN I, Hae III, Mbo I, PstI/Pvu II, and Rsa I. An average of 18 polymorphic fragments was observed using Hinf I as enzyme. The band sharing frequency after Hinf I digestion among unrelated individuals was determined to be 23.8 +/- 7.2%. An example for the application of MZ 1.3 to paternity testing in an incest case is given. The probe can be used with radioactive or non-radioactive detection systems. An approach is presented to compare polymorphic fragment patterns from individuals obtained by independent gel runs on the basis of relative band positions (RBP) and calculated in a computerized analysis.  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