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   17078篇
  免费   501篇
各国政治   702篇
工人农民   681篇
世界政治   1426篇
外交国际关系   583篇
法律   10262篇
中国共产党   2篇
中国政治   77篇
政治理论   3671篇
综合类   175篇
  2020年   212篇
  2019年   250篇
  2018年   325篇
  2017年   389篇
  2016年   420篇
  2015年   288篇
  2014年   333篇
  2013年   1667篇
  2012年   404篇
  2011年   431篇
  2010年   345篇
  2009年   379篇
  2008年   443篇
  2007年   461篇
  2006年   443篇
  2005年   392篇
  2004年   399篇
  2003年   416篇
  2002年   376篇
  2001年   678篇
  2000年   617篇
  1999年   509篇
  1998年   284篇
  1997年   243篇
  1996年   202篇
  1995年   203篇
  1994年   246篇
  1993年   218篇
  1992年   337篇
  1991年   371篇
  1990年   327篇
  1989年   345篇
  1988年   316篇
  1987年   335篇
  1986年   341篇
  1985年   331篇
  1984年   286篇
  1983年   316篇
  1982年   255篇
  1981年   237篇
  1980年   178篇
  1979年   246篇
  1978年   165篇
  1977年   145篇
  1976年   132篇
  1975年   120篇
  1974年   135篇
  1973年   117篇
  1972年   112篇
  1971年   94篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
991.
992.
993.
994.
995.
996.
997.
998.
The goal of the present study was to determine the relationship between substance use, drug selling, and lethal violence in adolescent male homicide offenders and their victims. The study employed a retrospective review of criminal justice databases and medical examiner records for murders committed by 25 adolescent males incarcerated in the Commonwealth of Virginia juvenile correctional centers from February 1992 to July 1996. The perpetrator sample was 84% African American and 16% white. The average age at the time of the offense was 15.0 years (range = 13.0 to 17.7 years). The victims were 84% male, 60% African American and 32% white. The median victim age was 28.0 years (mean = 34.8, range = 17 months to 75 years). The results indicated that 52% of the murders were committed by juveniles with identified involvement in drug selling, and 28% of the murders were drug-related. Toxicology results indicated recent drug or alcohol use in 27% of the victims; while 74% of the perpetrators reported substance use, 35% indicating daily use. Using discriminant analysis, it was possible to accurately classify 86% of the drug-related murders with the variables of recent victim drug use and perpetrator substance use history. The results indicated that adolescent males involved in the sale and distribution of illegal drugs comprised a significant percentage of those incarcerated for murder. Recent victim drug use and perpetrator substance use may be important variables in identifying drug-related juvenile homicides. These results underscore the link between substance use, drug selling, and lethal violence.  相似文献   
999.
Population genetics of nine STR loci in two populations from Brazil   总被引:2,自引:0,他引:2  
The Short Tandem Repeats (STRs) D3S1358, HUMvWA31/A, HUMFIBRA/FGA, D8S 1179, D2S11, D18S51, D5S818, D13S317, and D7S820 were studied in two Brazilian populations (from Amazonia and S. Paulo) using the "AmpF1 STR Profiler Plus PCR Amplification Kit." The nine loci showed a combined discrimination power greater than 0.9999999999 and a chance of exclusion of 0.9999.  相似文献   
1000.
Postmortem redistribution of morphine and its metabolites   总被引:2,自引:0,他引:2  
The postmortem redistribution of morphine, morphine-3-glucuronide, morphine-6-glucuronide and total morphine was assessed in 40 heroin-related deaths. In blood taken from subclavian, heart, and femoral regions, concentrations of morphine and its metabolites were similar. While there was a trend for higher concentrations in heart blood, when compared with femoral or subclavian blood, this was not significant. There was also no significant difference in concentrations between admission and autopsy blood in which the postmortem interval was on average 59 h. From our observations, significant postmortem redistribution of morphine and its metabolites seems unlikely.  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