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   10356篇
  免费   324篇
各国政治   291篇
工人农民   507篇
世界政治   611篇
外交国际关系   313篇
法律   6655篇
中国共产党   34篇
中国政治   129篇
政治理论   2003篇
综合类   137篇
  2021年   62篇
  2020年   150篇
  2019年   134篇
  2018年   206篇
  2017年   244篇
  2016年   280篇
  2015年   229篇
  2014年   228篇
  2013年   852篇
  2012年   245篇
  2011年   282篇
  2010年   213篇
  2009年   281篇
  2008年   338篇
  2007年   350篇
  2006年   337篇
  2005年   306篇
  2004年   298篇
  2003年   247篇
  2002年   242篇
  2001年   354篇
  2000年   327篇
  1999年   259篇
  1998年   156篇
  1997年   115篇
  1996年   144篇
  1995年   117篇
  1994年   131篇
  1993年   133篇
  1992年   202篇
  1991年   255篇
  1990年   217篇
  1989年   202篇
  1988年   222篇
  1987年   204篇
  1986年   222篇
  1985年   196篇
  1984年   164篇
  1983年   159篇
  1982年   102篇
  1981年   125篇
  1980年   102篇
  1979年   103篇
  1978年   92篇
  1977年   78篇
  1976年   65篇
  1975年   65篇
  1974年   68篇
  1973年   80篇
  1969年   53篇
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
971.
The Fourth Amendment to the US Constitution provides protection of all citizens against unreasonable search and seizure. The US Supreme Court has affirmed that the basic purpose of the Fourth Amendment is to safeguard the privacy and security of individuals against unreasonable intrusive searches by governmental officials. Since students possess constitutional rights and public school officials are considered governmental officials for Fourth Amendment purposes, privacy protection is afforded students in public schools within reasonable limits. A reasonable search is one that clearly does not violate the constitutional rights of students. What is reasonable, however, depends on the context within which a search occurs. Strip searches involving students in public schools are the most intrusive form of all searches. Extreme caution should be exercised by school officials regarding these types of searches.  相似文献   
972.
Conventional wisdom suggests that individual members of Congress have no real incentive to act in ways that might improve public evaluations of their collective body. In particular, the literature provides no clear evidence that public evaluations of Congress affect individual races for Congress, and little reason to expect that voters would hold specific individuals responsible for the institution's performance. We suggest that this conventional wisdom is incorrect. Using multiple state‐level exit polls of Senate voting conducted by Voter News Service in 1996 and 1998, we arrive at two key findings. First, we find that evaluations of Congress do have a significant effect on voting within individual U.S. Senate races across a wide variety of electoral contexts. Second, we find that punishments or rewards for congressional performance are not distributed equally across all members, or even across members of a particular party. Instead, we find that the degree to which citizens hold a senator accountable for congressional performance is significantly influenced by that senator's actual level of support for the majority party in Congress, as demonstrated on party votes.  相似文献   
973.
974.
This investigation examines the possibility of interaction between tranylcypromine and butorphanol in comparison to pethidine. The LD50 of pethidine and butorphanol were determined in mice pretreated with the non-selective monoamine oxidase (MAO) inhibitor, tranylcypromine orally for 8 days or with oral saline solution. Tranylcypromine decreased the LD50 of both pethidine and butorphanol by 78% and 41%, respectively. Anesthetized rabbits with halothane pretreated with tranylcypromine or saline were given pethidine (5 mg/kg i.v.) or butorphanol (0.5, 1 and 2 mg/kg i.v.). Pethidine produced a marked increase in blood pressure in rabbits pretreated with tranylcypromine and did not affect significantly the heart rate. Butorphanol did not affect either blood pressure or heart rate at doses of 0.5 or 1 mg/kg. However, the largest dose of butorphanol (2 mg/kg) produced hypotension and tachycardia in rabbits pretreated with tranylcypromine. Neither pethidine nor butorphanol affected the temperature of anesthetized rabbits pretreated with tranylcypromine or saline.  相似文献   
975.
976.
977.
This article presents a comprehensive overview of joint custody. The history and legislative implications are discussed, as are pertinent issues relative to the reported advantages and disadvantages of joint custody. Finally, the role of the mental health professional in assisting with counseling divorced families either before, during, or after a custody decision is discussed.  相似文献   
978.
979.
980.
The recent formation of a United Kingdom and Irish working group, the Body Fluids Forum (BFF), highlighted the need to investigate different working practices prior to any inter-laboratory comparison work and identification of best practice. Various dilutions of semen were seeded onto swabs and cloth samples for each BFF member laboratory to test using their standard techniques. The results showed that the detection of acid phosphatase on swabs is best achieved using direct testing rather than on an extract from the swab. Extraction methods for spermatozoa require a balance to be achieved between using a sufficient volume of water to ensure optimal release and minimal volume to ensure a concentrated extract. PSA tests were investigated and found to be more sensitive than Choline. DNA profiles were obtained from samples in which no spermatozoa had been detected during microscopic examination.  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