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   3430篇
  免费   55篇
各国政治   97篇
工人农民   93篇
世界政治   145篇
外交国际关系   95篇
法律   2649篇
中国政治   17篇
政治理论   352篇
综合类   37篇
  2020年   33篇
  2019年   34篇
  2018年   54篇
  2017年   42篇
  2016年   63篇
  2015年   28篇
  2014年   51篇
  2013年   245篇
  2012年   86篇
  2011年   132篇
  2010年   79篇
  2009年   61篇
  2008年   108篇
  2007年   121篇
  2006年   106篇
  2005年   84篇
  2004年   121篇
  2003年   113篇
  2002年   109篇
  2001年   150篇
  2000年   134篇
  1999年   103篇
  1998年   20篇
  1995年   17篇
  1993年   27篇
  1992年   62篇
  1991年   83篇
  1990年   85篇
  1989年   91篇
  1988年   95篇
  1987年   89篇
  1986年   75篇
  1985年   77篇
  1984年   67篇
  1983年   58篇
  1982年   24篇
  1981年   20篇
  1979年   30篇
  1978年   33篇
  1977年   22篇
  1976年   27篇
  1975年   28篇
  1974年   37篇
  1973年   37篇
  1972年   35篇
  1971年   36篇
  1970年   38篇
  1969年   32篇
  1968年   27篇
  1967年   18篇
排序方式: 共有3485条查询结果,搜索用时 15 毫秒
151.
Two intravenous amphetamine abusers had fatal, rapidly progressive cerebral mucormycosis with abscess formation in the presence of absolute lymphopenia. Postmortem examination confirmed the primary nature of the fungal cerebritis, documented by postmortem culture and histology. The clinical and pathologic features of these cases are compared to previously reported occurrences of primary fungal cerebritis (and abscess) among intravenous drug abusers, including cocaine users. Primary fungal cerebritis associated with intravenous abuse of stimulant drugs is discussed as a possible variant of the acquired immunodeficiency syndrome.  相似文献   
152.
153.
154.
155.
156.
157.
158.
Specimens from fatal aviation accident victims are submitted to the FAA Civil Aerospace Medical Institute for toxicological analysis. During toxicological evaluations, ethanol analysis is performed on all cases. Care must be taken when interpreting a positive ethanol result due to the potential for postmortem ethanol formation. Several indicators of postmortem ethanol formation exist; however, none are completely reliable. The consumption of ethanol has been shown to alter the concentration of two major serotonin metabolites, 5-hydroxytryptophol (5-HTOL) and 5-hydroxyindole-3-acetic acid (5-HIAA). While the 5-HTOL/5-HIAA ratio is normally very low, previous studies using living subjects have demonstrated that the urinary 5-HTOL/5-HIAA ratio is significantly elevated for 11-19 h after acute ethanol ingestion. Recently, our laboratory developed and validated an analytical method for the simultaneous determination of both 5-HTOL and 5-HIAA in forensic urine samples using a simple liquid/liquid extraction and LC/MS/MS and LC/MS/MS/MS. In this previous work a 15 pmol/nmol serotonin metabolite ratio cutoff was established in postmortem urine, below which it could be conclusively determined that no recent antemortem ethanol consumption had occurred. In the current study this newly validated analytical method was applied to five ethanol-positive aviation fatalities where the origin of the ethanol present could not previously be conclusively determined. In four of the five cases examined the detected ethanol was demonstrated to be present due to postmortem microbial formation, and not consumption, even though some indication of ethanol consumption may have been present.  相似文献   
159.
A method was suggested for identifying reladorm and donormil in pharmaceutical drugs and biological objects. The above substances are isolated by 96% ethanol or by mixture of chloroform and isopropanol. 7 color reactions, 3 microcrystalloscopic reactions and chromatography in thin sorbent layer are suggested for identification.  相似文献   
160.
Posttraumatic alterations in the cervical spine ligaments were studied clinically and psychologically in the victims with mechanical injuries of the musculoligamentous system of the cervical spine. A clinical course of the traumatic process and biomechanical musculoligamentous alterations, development and severity of mental disorders were established. These characteristics should be taken into consideration in forensic medical evaluation of health deterioration.  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