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   68314篇
  免费   3018篇
各国政治   4575篇
工人农民   2915篇
世界政治   6074篇
外交国际关系   3862篇
法律   31445篇
中国共产党   12篇
中国政治   828篇
政治理论   20661篇
综合类   960篇
  2021年   424篇
  2020年   1192篇
  2019年   1556篇
  2018年   1709篇
  2017年   1993篇
  2016年   2203篇
  2015年   1848篇
  2014年   2122篇
  2013年   10588篇
  2012年   1643篇
  2011年   1724篇
  2010年   1839篇
  2009年   2074篇
  2008年   1745篇
  2007年   1706篇
  2006年   1877篇
  2005年   1750篇
  2004年   1675篇
  2003年   1451篇
  2002年   1495篇
  2001年   1558篇
  2000年   1357篇
  1999年   1179篇
  1998年   1080篇
  1997年   967篇
  1996年   947篇
  1995年   900篇
  1994年   898篇
  1993年   926篇
  1992年   939篇
  1991年   962篇
  1990年   935篇
  1989年   963篇
  1988年   947篇
  1987年   981篇
  1986年   932篇
  1985年   1001篇
  1984年   911篇
  1983年   955篇
  1982年   888篇
  1981年   830篇
  1980年   646篇
  1979年   680篇
  1978年   578篇
  1977年   508篇
  1976年   475篇
  1975年   399篇
  1974年   412篇
  1973年   422篇
  1972年   372篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
261.
Good gas chromatography (GC) separation of molecules is essential for clean gas chromatography/mass spectrometry (GC/MS) confirmation of compounds. The trifluoro derivatives of ephedrine (E) and methamphetamine (MA) coelute on dimethyl silicone capillary columns, such as DB-1, which are most commonly used by chromatographers. Methods are described to separate E and MA to aid GC/MS confirmations of methamphetamine, ephedrine, or both E and MA together, whichever may be present in Enzyme Immunoassay (EIA)-analyzed amphetamine-positive urine samples. The use of the heptafluoro derivatives of E and MA on a DB-1 column, or the trifluoro derivatives of E and MA on a DB-17 column, is suggested for good gas chromatographic separation.  相似文献   
262.
The Supreme Court early took note of extralegal, “social science” materials in Muller v. Oregon (1908), and a half-century later made specific reference to social science authorities in the famous footnote 11 of Brown v. Board of Education (1954). Since Brown, much has been written about the Supreme Court's use of social science research evidence, but there has been little systematic study of that use. Those writing on the subject commonly focus on areas of law such as jury size, where social science has been used, and have generally assumed that social science information has been utilized in Supreme Court decisions with increasing regularity. Surprisingly little is known, however, about either the justices' baseline use of social science authorities, or many other aspects of their uses of social science information. The focus here is on the citation of social science research evidence in a sample of 240 criminal cases decided during the 30 years between the Supreme Court's 1958 and 1987 Terms. The resulting portrait contributes to a fuller understanding of the justices' use of social science materials, and may ultimately help promote more effective utilization of social science research evidence in Supreme Court decisions.  相似文献   
263.
264.
265.
266.
267.
The extent to which local life circumstances influence criminal activity has been the focus of much theoretical debate. Although empirical research has been initiated, it remains limited. Herein, we use data on 524 serious offenders from the California Youth Authority for a seven‐year post‐parole period to examine the relationship between changes in local life circumstances and criminal activity. We extend previous research by employing a statistical model that accounts for the joint distribution of violent and nonviolent crime during the late teens and twenties in order to present information on patterns of criminal activity during a newly recognized developmental period of the life course, “emerging adulthood.”  相似文献   
268.
On the basis of the uncertainty management model, we argue here that when people are uncertain about an organization's trustworthiness, they may resolve the question how they should react toward the organization by relying on their perceptions of the organization's procedures. As a consequence, we predicted that the reactions of parents whose child was in a day care center would be strongly influenced by their perceptions of the procedures used by the organization that was responsible for their children's day care when the parents would be uncertain about the organization's trustworthiness. However, when parents would be certain that the organization could be trusted they would be less in need of procedural information, yielding less strong effects of perceived procedure on parents' reactions. The findings of a survey study corroborate this line of reasoning. In the discussion it is argued that these findings suggest that people especially rely on their perceptions of procedures when they are uncertain about important aspects of their lives, such as the trustworthiness of organizations that are responsible for their children's day care.  相似文献   
269.
This article discusses relevant literature on the potential benefits of sport, recreation, and leisure, and how these benefits relate to rehabilitation of juveniles. Many professionals involved in juvenile rehabilitation believe sport and recreation are beneficial adjuncts to treatment programming; however, it can be difficult to structure sport and recreation in ways that directly correspond to treatment goals. The purpose of this article is to provide insights for professionals working with juveniles on how sport and recreation programming can be an effective means of helping to achieve rehabilitation goals. Attention is given to approaches, particularly the Teaching Games for Understanding model (Bunker & Thorpe, 1982), which can be used to effectively link recreation and sport to the rehabilitation process.  相似文献   
270.
颅脑损伤患者智能和记忆损害的相关因素研究   总被引:3,自引:0,他引:3  
目的探讨交通事故所致颅脑损伤伤者的智能和记忆损害及相关因素。方法 统计分析成都市1999年1月1日至2001年12月31日间因交通事故造成颅脑损伤的652例伤者的心理测验、脑电图及脑影像学资料。结果研究组平均智商为77.85±15.97,27.9%的伤者智商低于70;51.9%的记忆商低于51。智力损害与文化程度、左颞叶损伤、≥3个脑叶损伤以及脑电图异常明显相关;记忆损害与文化程度、损伤和鉴定检查的间隔时间、脑于损伤、左颞叶损伤、脑电图异常明显相关。结论交通事故造成颅脑损伤的伤者多有不同程度的智力和记忆损害,且与左颞叶损伤、脑电图异常、文化程度、脑干损伤等因素有关。  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