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   10659篇
  免费   344篇
各国政治   304篇
工人农民   551篇
世界政治   654篇
外交国际关系   421篇
法律   6740篇
中国共产党   34篇
中国政治   130篇
政治理论   2033篇
综合类   136篇
  2021年   64篇
  2020年   154篇
  2019年   138篇
  2018年   218篇
  2017年   253篇
  2016年   294篇
  2015年   238篇
  2014年   233篇
  2013年   897篇
  2012年   254篇
  2011年   300篇
  2010年   225篇
  2009年   295篇
  2008年   358篇
  2007年   389篇
  2006年   360篇
  2005年   324篇
  2004年   317篇
  2003年   256篇
  2002年   255篇
  2001年   358篇
  2000年   338篇
  1999年   265篇
  1998年   160篇
  1997年   120篇
  1996年   147篇
  1995年   120篇
  1994年   136篇
  1993年   136篇
  1992年   206篇
  1991年   252篇
  1990年   219篇
  1989年   200篇
  1988年   224篇
  1987年   206篇
  1986年   221篇
  1985年   197篇
  1984年   165篇
  1983年   159篇
  1982年   104篇
  1981年   129篇
  1980年   102篇
  1979年   105篇
  1978年   91篇
  1977年   78篇
  1976年   64篇
  1975年   64篇
  1974年   66篇
  1973年   80篇
  1971年   50篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
991.
992.
The armamentarium of the forensic thanatologist includes the examiner's subjective assessment of bodily changes together with comprehensive evaluation of environmental and associated factors to estimate the postmortem interval (PMI). Of the various objective means, postmortem accumulation of potassium in vitreous humor is a widely used gauge. In view of the considerable variability inherent in these techniques, an additional marker with greater accuracy would be a welcome supplement to these indices. We have developed a method of estimating PMI from the level of 3-methoxytyramine (3-MT) in the dorsal putamen of the brain. The supernatant of a sample of putamen, sonicated in 6 volumes (weight/volume) of 0.1 M perchloric acid and centrifuged at 51 000 times gravity for 10 min, was analyzed for 3-MT using high-pressure liquid chromatography with electrochemical detection. The change of 3-MT in the putamen is linearly related to the PMI (range: 5.5 to 60 h), irrespective of patient age (1 to 84 years). This observation is attributable to several factors, including high substrate (dopamine) concentration, preservation of catechol-O-methyl transferase activity, and an inactivation of monoamine oxidase activity, as a result of a decrease in tissue pO2.  相似文献   
993.
For the last several centuries, most jurisdictions using capital punishment have had formal or informal rules that prohibit the execution of the mentally ill. In this article, the procedures for such exclusions in Florida are examined. The article begins by attempting to answer the question of why legislators and judges, at least nominally, have prohibited the execution of the mentally ill. Next, Florida's criteria for defining and procedures for excluding mentally ill prisoners are examined and found to be vague. We then turn attention to the ethical problems created by the statute and its implementation that face the participating psychiatrists and the profession. These problems are compounded because the physician's findings are not acted upon by politically neutral authorities and the inmate has no opportunity to challenge the findings with his own panel of experts. Finally, since any exclusion of the mentally ill from execution is temporary and the patient will be executed if he recovers, the dilemmas facing the treatment staff if the death sentence is not commuted to life imprisonment before treatment are discussed.  相似文献   
994.
冯友兰是中国近现代史上著名的哲学家和哲学史家。他从中国文化和中国社会发展方向的前提出发,比较中西文化之间的差异,形成了关于文化问题和社会发展问题的一系列观点。他所提出的以“文化类型”说、“继往开来”说和“道统新续”说为内容的“文化三说”观,对于妥善处理中西文化冲突与融合过程中的时代性和民族性的关系,以及如何弘扬中国传统文化的精华与吸收外国文化的长处等问题,仍然具有积极的现实启迪意义。  相似文献   
995.
996.
997.
998.
In July 2005, the Little Rock, Arkansas, school district implemented a new policy to reorganize its management structure in order to create a more efficient bureaucracy. Using Richard Matland’s ambiguity‐conflict model of policy implementation, the authors examine the implementation of this school reorganization policy. Interviews and surveys were conducted with the superintendent and his executive assistants, school principals, teachers, and staff. In line with Matland’s model, the findings suggest that successful implementation is directly related to the policy characteristics of ambiguity and conflict. However, the authors point to the importance of recognizing particular characteristics for different groups of stakeholders within the policy implementation process. Discrepancies among groups of policy actors in the degree of policy ambiguity and policy conflict lead to strikingly different implementation strategies.  相似文献   
999.
Chloroquine concentrations in blood and tissues were examined in overdose and non-overdose cases to determine appropriate ranges for interpretation. Twenty-nine literature overdose cases and 8 non-overdose literature cases were compared with this laboratory's findings. The results indicate significant postmortem redistribution of chloroquine. Combining this laboratory's results and the literature results indicates that using a liver concentration of 150 mg/kg as a cutoff between overdose and non-overdose concentrations properly identified 30 of the 34 published cases containing liver chloroquine and 19 of the 20 presented cases.  相似文献   
1000.
A simple and rapid method for the isolation of seven synthetic pyrethroid insecticides (methothrin, fenpropathrin, cyhalothrin, permethrin, cypermethrin, fenvalerate, deltamethrin) with a solid phase extraction (SPE), utilizing Sep-Pak C18 cartridges, from human urine and plasma is presented. The detection of the insecticides was performed using a wide bore capillary gas chromatograph (GC) with flame ionization detection (FID). The insecticide-containing samples mixed with 70% methanol were directly applied to the cartridges and eluted with 2 ml chloroform. The recoveries using the cartridges were between 90-102% for urine and 81-93% for plasma. Mixing samples with 70% methanol prior to extraction, seems very useful for the screening of synthetic pyrethroid insecticides.  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