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   17810篇
  免费   617篇
  国内免费   5篇
各国政治   766篇
工人农民   796篇
世界政治   1239篇
外交国际关系   638篇
法律   11239篇
中国共产党   6篇
中国政治   160篇
政治理论   3400篇
综合类   188篇
  2020年   241篇
  2019年   322篇
  2018年   386篇
  2017年   456篇
  2016年   463篇
  2015年   334篇
  2014年   368篇
  2013年   1718篇
  2012年   497篇
  2011年   525篇
  2010年   426篇
  2009年   467篇
  2008年   546篇
  2007年   585篇
  2006年   541篇
  2005年   501篇
  2004年   505篇
  2003年   524篇
  2002年   455篇
  2001年   708篇
  2000年   588篇
  1999年   504篇
  1998年   262篇
  1997年   185篇
  1996年   211篇
  1995年   182篇
  1994年   215篇
  1993年   209篇
  1992年   338篇
  1991年   372篇
  1990年   363篇
  1989年   295篇
  1988年   339篇
  1987年   284篇
  1986年   328篇
  1985年   297篇
  1984年   240篇
  1983年   232篇
  1982年   186篇
  1981年   195篇
  1980年   133篇
  1979年   183篇
  1978年   128篇
  1977年   109篇
  1976年   103篇
  1975年   128篇
  1974年   137篇
  1973年   111篇
  1972年   105篇
  1969年   100篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
91.
A gas chromatographic (GC) fingerprint method, based on the presence or absence of six congeners, was developed for illicit cocaine samples. The fingerprint utilizes the relative abundances of these congeners towards each other, disregarding cocaine as the main constituent, and can be expressed numerically or graphically in the form of pictograms for rapid visual comparison. The method can be applied directly to a solution of the sample in chloroform, without previous workup procedures. More than 70 unrelated samples were analyzed and a great variation was observed in the parameter composition. On the other hand, a remarkable similarity could be seen between related samples. The GC fingerprint method may be considered an important contribution for sample comparison, as is exemplified by a subdivision of the analyzed samples in different categories, based on the number and types of congeners found.  相似文献   
92.
We report a case of rapid death from thrombotic thrombocytopaenic purpura (TTP) in a young pregnant lady who developed full blown symptoms soon after caesarean section. Extensive intramyocardial confluent haemorrhages and widespread microthrombi in heart, brain, adrenals and kidney were found at autopsy. Thrombotic thrombocytopaenic purpura is an uncommon condition, which carries a high fatality rate if untreated. Awareness of this syndrome together with its high risk of sudden death underlines the importance of rapid diagnosis and treatment.  相似文献   
93.
A new solid-phase extraction procedure for the determination of cocaine and benzoylecgonine in amniotic fluid, using high flow co-polymeric sorbents is reported. The recoveries of cocaine and benzoylecgonine within the range 0.1-1 mg/l were 95.7% and 50.3%, respectively. The use of high-flow sorbents allowed the easy extraction of amniotic fluid regardless of sample viscosity or physical nature. The use of these solid-phase columns provided many advantages over the more commonly used solvent extraction, including an increase in extraction speed and efficiency, reduced operator time, reduced solvent use and disposal volumes and exceptional extract quality. Further, the determination of amniotic fluid obtained from pregnant cocaine users may provide important information about handling of cocaine by the fetus at various gestational ages. The procedure was successfully applied to amniotic fluid from suspected cocaine abusers.  相似文献   
94.
In many types of social situations, individuals defend their claims to a portion of the rewards by arguing that they are just. Although a great deal of research demonstrates that individuals differ in their distribution preferences and thus their beliefs about what is fair, the literature curiously omits consideration of the consequences of these differences, especially the conflict they may engender. This paper first reviews the few attempts to address such justice conflict. The limitations of these approaches suggest concerns to be addressed in an alternative framework. The paper presents a theoretical discussion of this alternative that integrates assumptions about distribution preferences, justice beliefs, conditions fostering the emergence of justice conflict, and elements of negotiation processes as a basic framework for predictions about the bargaining strategies individuals may employ to resolve competing justice claims.  相似文献   
95.
96.
97.
98.
99.
100.
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