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   8101篇
  免费   257篇
各国政治   501篇
工人农民   346篇
世界政治   522篇
外交国际关系   375篇
法律   4821篇
中国政治   44篇
政治理论   1699篇
综合类   50篇
  2020年   107篇
  2019年   130篇
  2018年   175篇
  2017年   211篇
  2016年   221篇
  2015年   142篇
  2014年   189篇
  2013年   940篇
  2012年   186篇
  2011年   194篇
  2010年   192篇
  2009年   196篇
  2008年   215篇
  2007年   219篇
  2006年   214篇
  2005年   182篇
  2004年   169篇
  2003年   192篇
  2002年   156篇
  2001年   290篇
  2000年   248篇
  1999年   232篇
  1998年   104篇
  1997年   90篇
  1996年   76篇
  1995年   68篇
  1994年   75篇
  1993年   71篇
  1992年   125篇
  1991年   160篇
  1990年   154篇
  1989年   145篇
  1988年   149篇
  1987年   168篇
  1986年   159篇
  1985年   149篇
  1984年   132篇
  1983年   121篇
  1982年   83篇
  1981年   91篇
  1980年   69篇
  1979年   126篇
  1978年   87篇
  1977年   73篇
  1976年   56篇
  1975年   81篇
  1974年   86篇
  1973年   82篇
  1972年   56篇
  1971年   58篇
排序方式: 共有8358条查询结果,搜索用时 31 毫秒
951.
952.
953.
954.
955.
956.
A high selective screening test (Ad-Tip method) for methamphetamine in human urine has been devised. The method involves a brief extraction from a urine sample with an Ad-Tip (ODS-silica minicolumn), washing, eluting with modified Simon's reagent, and coloration with carbonate buffer. Detection limit of methamphetamine in urine is 1 microgram/ml and the test takes within 3 min/sample. The results of the Ad-Tip method were almost identical to those of laboratory analyses.  相似文献   
957.
Presented is a case of murder by means of chloroquine, committed on a 36-year-old male. The wife of the deceased had confessed to have secretely administered chloroquine-containing tablets to her husband. She was lawfully sentenced to life-imprisonment. The toxicological findings of this case are compared to the results of two chloroquine suicide cases and discussed in the context of the referring literature. An additional case where chloroquine intoxication was doubtful is introduced because of the unusual circumstances under which it occurred.  相似文献   
958.
Commotio cordis, revisited   总被引:1,自引:0,他引:1  
Nonpenetrating cardiac injuries due to direct precordial blunt impacts are a commonly encountered phenomenon in medicolegal offices. These injuries vary from contusions to valvular lacerations, or papillary muscle rupture to coronary arterial injury with resulting infarction. A less commonly occurring manifestation of nonpenetrating injury is a concussion of the heart (commotio cordis), often with dramatic physiological consequences but no morphologic cardiac injury. We describe four case reports of this entity. The cases were collected over a 5-year period (1978-1983) from the Wayne County Medical Examiner's Office in Detroit, Michigan.  相似文献   
959.
960.
Sudden unexpected nocturnal death syndrome in the Mariana Islands   总被引:1,自引:0,他引:1  
Sudden unexpected nocturnal death syndrome (SUNDS) is a distinct clinical entity in previously healthy, young, Southeast Asian males. It is well known in the Philippines and more recently recognized in the U.S. by nonspecific autopsy findings, with no evidence of underlying disease and absence of toxic drug or alcohol levels. In 1973-89, 14 cases of apparent SUNDS came to coroner's autopsy in the Commonwealth of the Northern Marianas (CNMI) and Guam. All 14 cases, with the exception of one Yapese, were previously healthy, male Filipinos, aged 23 to 55, who were either found dead in bed, or described by their colleagues as having nocturnal seizure activity consisting of gurgling, frothing, and tongue biting immediately prior to death. Autopsy findings showed no anatomic findings to account for death. Comprehensive serum and urine drug analyses were negative. All decedents showed absence of significant atherosclerosis or grossly detectable structural cardiac anomaly, while four showed cardiomegaly. Migrants from Southeast Asia carry with them a pre-disposition to this syndrome, which appears to decline with longer residence in the new country. The mechanism of death in SUNDS is believed to be ventricular fibrillation, possibly precipitated by sudden sympathetic discharge. Studies suggest at least some deaths may be associated with an abnormal cardiac conduction system. Acute pancreatitis has been a finding in some series, but not our cases. Why the condition is virtually limited to males and seemingly sleep-triggered, has not been adequately explained. Stress and depression are believed to be predisposing factors.  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