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   381篇
  免费   18篇
各国政治   22篇
工人农民   5篇
世界政治   52篇
外交国际关系   43篇
法律   163篇
中国政治   2篇
政治理论   108篇
综合类   4篇
  2021年   3篇
  2020年   6篇
  2019年   5篇
  2018年   13篇
  2017年   15篇
  2016年   11篇
  2015年   12篇
  2014年   11篇
  2013年   78篇
  2012年   14篇
  2011年   16篇
  2010年   14篇
  2009年   17篇
  2008年   12篇
  2007年   19篇
  2006年   8篇
  2005年   12篇
  2004年   10篇
  2003年   5篇
  2002年   10篇
  2001年   11篇
  2000年   9篇
  1999年   1篇
  1998年   4篇
  1997年   6篇
  1996年   3篇
  1995年   4篇
  1994年   3篇
  1993年   6篇
  1992年   3篇
  1991年   1篇
  1990年   3篇
  1989年   6篇
  1987年   4篇
  1986年   5篇
  1985年   3篇
  1984年   5篇
  1983年   2篇
  1982年   1篇
  1981年   1篇
  1979年   3篇
  1978年   5篇
  1977年   3篇
  1976年   1篇
  1975年   2篇
  1974年   2篇
  1973年   4篇
  1972年   3篇
  1970年   1篇
  1967年   1篇
排序方式: 共有399条查询结果,搜索用时 15 毫秒
31.
32.
Fifty-one years ago, when liberalism and social welfare democracy were expanding in all advanced industrialized nations, V.O. Key, Jr., forecast the decline of postwar liberalism in the United States. Current discussion of the decline of liberalism has ignored Key or, when evidence is lacking, has incorrectly cited him. In contrast to Key's relatively direct, simple, and heavily documented reasoning, current explanations are multifactorial, complex, less well documented, and often ideologically loaded. Some explanations for the postwar decline identify causal factors more than six years after the war, yet they ignore events in 1945–47. At the fifty-first anniversary of V.O. Key's Southern Politics in State and Nation, attention to Key's forecast and Occam's razor is called for. Key argued that racism in the South, exerted through congressional committees, would lead to a decline of liberalism in the nation. Using legislative histories, this article compares Key's single-factor racial explanation with a two-factor explanation—and by implication with multifactor ones—and finds Key's more compelling and parsimonious. Archival sources indicate that more than two years before the 1948 Democratic Convention, Charlie Ross, Truman's closest advisor, and Truman himself encouraged Key to assess the emerging postwar politics of the South. As Key anticipated, institutionalized racism sunk the Fair Deal and postwar social democracy, despite Truman's efforts. The effects of racism on postwar and current politics and public administration should be reexamined as a key to understanding American distinctiveness or exceptionalism.  相似文献   
33.
34.
35.
36.
Previous investigations on calvarial fractures in infants have shown that the flexibility and displacement of the infant calvarial are not sufficient to avoid fractures as a result of fall. From a table height onto hard ground - and in special cases, fractures cannot be avoided even after falls onto softly cushioned ground. The skull fractures are located in paper-thin, transparent, single-layer bone areas without diploe. The results of previous literature were compared with investigations of the skulls of 82 infants (from neonates up to infants 14 months of age). Congenital fissures, cranioschisis, locally retarded ossification in the cranium and craniotabes are all weak points where fracture has a tendency to occur even if the impact is minor. These ossification defects are increased in the ossa parietalia, but can also be found in the os frontale or in the os occipitale. The location is not always the same but can be detected by locating the skull transparency using diaphanoscopy.  相似文献   
37.
38.
39.
40.
Banknote evidence is often submitted after a suspect has attempted to disguise or remove red dye stain that has been released because of an anti-theft device that activates after banknotes have been unlawfully removed from bank premises. Three chlorinated compounds have been synthesized as forensic chemical standards to indicate bank security dye bleaching as a suspect's intentional method for masking a robbery involving dye pack release on banknotes. A novel, facile synthetic method to provide three chlorinated derivatives of 1-(methylamino)anthraquinone (MAAQ) is presented. The synthetic route involved Ultra Clorox bleach as the chlorine source, iron chloride as the catalyst, and MAAQ as the starting material and resulted in a three-component product mixture. Two mono-chlorinated isomers (2-chloro-1-(methylamino)anthraquinone and 4-chloro-1-(methylamino)anthraquinone) and one di-chlorinated compound (2,4-dichloro-1-(methylamino)anthraquinone) of the MAAQ parent molecule were detected by gas chromatography mass spectrometry (GC-MS), and subsequently isolated by liquid chromatography (LC) with postcolumn fraction collection. Although GC-MS is sensitive enough to detect all of the chlorinated products, it is not definitive enough to identify the structural isomers. Liquid-state nuclear magnetic resonance (NMR) spectroscopy was utilized to elucidate structurally the ortho- and para-mono-chlorinated isomers once enough material was properly isolated. A reaction mechanism involving iron is proposed to explain the presence of chlorinated MAAQ species on stolen banknotes after attempted bleaching.  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