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   33663篇
  免费   286篇
  国内免费   5篇
各国政治   1234篇
工人农民   1900篇
世界政治   2055篇
外交国际关系   1303篇
法律   20334篇
中国共产党   7篇
中国政治   202篇
政治理论   6712篇
综合类   207篇
  2021年   153篇
  2020年   389篇
  2019年   476篇
  2018年   1682篇
  2017年   1705篇
  2016年   1595篇
  2015年   563篇
  2014年   560篇
  2013年   2385篇
  2012年   804篇
  2011年   1569篇
  2010年   1523篇
  2009年   1178篇
  2008年   1402篇
  2007年   1344篇
  2006年   740篇
  2005年   729篇
  2004年   819篇
  2003年   817篇
  2002年   649篇
  2001年   1021篇
  2000年   880篇
  1999年   712篇
  1998年   422篇
  1997年   311篇
  1996年   344篇
  1995年   309篇
  1994年   355篇
  1993年   321篇
  1992年   493篇
  1991年   530篇
  1990年   515篇
  1989年   461篇
  1988年   495篇
  1987年   434篇
  1986年   512篇
  1985年   469篇
  1984年   385篇
  1983年   383篇
  1982年   287篇
  1981年   307篇
  1980年   209篇
  1979年   296篇
  1978年   205篇
  1977年   188篇
  1976年   162篇
  1975年   165篇
  1974年   196篇
  1973年   162篇
  1972年   157篇
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
921.
The authors report the case of a 21-year-old man who was killed while duck hunting when a shotgun accidentally discharged, shooting him in the head. The loaded weapon, which had been lying on the ground with the safety off and the muzzle pointed toward a river a few feet away, discharged when a hunting dog stepped on the trigger. Scene investigation confirmed that the victim had been standing in the river, planting decoys, with his head approximately level with the adjacent bank. Autopsy examination and ballistic testing confirmed a range of fire consistent with the witness' statements. Examination of the weapon in question documented a light trigger pull but no mechanical defects. The authors review the epidemiology and causality of hunting accidents and discuss the various safety rules that were violated in this highly unusual case. The importance of a complete death investigation, including autopsy, when dealing with a firearm death is emphasized.  相似文献   
922.
We describe a minisequencing protocol for screening DNA samples for the presence of 12 mutations in the human melanocortin 1 receptor gene (MC1R), eight of which are associated with the red hair phenotype. A minisequencing profile which shows homozygosity for one of these mutations or the presence of two different mutations would strongly indicate that the sample donor is red haired. The absence of any red hair causing mutations would indicate that the sample donor does not have red hair. We report the frequencies of MC1R variants in the British red haired population.  相似文献   
923.
With increasing commercial use of video surveillance to deter crime, physical anthropologists are becoming more involved in the forensic identification of persons based on photographic evidence. Three contrasting case studies from southern Florida are presented that illustrate the utilization of conventional anthropometry in determining the identity of suspects. In each case an arrested suspect and a subject videotaped during the commission of a crime are compared with respect to a series of discrete craniofacial and post-cranial proportions. Each case analysis is supplemented by additional data on earlobe structure, head and facial hair patterns, degree of chin eminence, presence or absence of tattoos, and various aspects of bodily dimensions and physique including height and weight estimations.  相似文献   
924.
To obtain a reference DNA profile from a missing person, we analyzed a variety of personal effects, including two lip cosmetics, both of which gave full DNA profiles. Further investigations were undertaken to explore this previously unreported source of DNA. We have tested a range of brands and types of lip cosmetics. Our studies have revealed that lip cosmetics are an excellent source of DNA, with almost 80% of samples giving a result. However, artifacts are frequently observed in the DNA profiles when Chelex is used for the DNA extraction and additional DNA purification procedures are required to ensure that an accurate DNA profile is obtained.  相似文献   
925.
Allele and haplotype frequencies of seven Y-chromosome STR loci from samples of 108 unrelated Japanese males living in Aichi Prefecture.  相似文献   
926.
The authors tested whether use of an electro shock weapon (stun gun) leaves marks on skin which can be found in an exterior examination. On pig skin such marks could not be produced postmortally. An experiment on one of the authors caused reddish skin marks which persisted for about 2 h. Inability to act as promised by the weapons' manufacturers did not occur in our experiments, exactly as previously described by other authors. Use of an air tester which shoots barbed electrodes ought to produce bleedings if the electrodes actually penetrate the skin.  相似文献   
927.
928.
929.
930.
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