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   758篇
  免费   41篇
各国政治   63篇
工人农民   44篇
世界政治   44篇
外交国际关系   35篇
法律   439篇
中国政治   1篇
政治理论   172篇
综合类   1篇
  2023年   7篇
  2022年   8篇
  2021年   6篇
  2020年   14篇
  2019年   23篇
  2018年   43篇
  2017年   55篇
  2016年   36篇
  2015年   29篇
  2014年   31篇
  2013年   111篇
  2012年   39篇
  2011年   36篇
  2010年   34篇
  2009年   22篇
  2008年   25篇
  2007年   39篇
  2006年   24篇
  2005年   27篇
  2004年   22篇
  2003年   26篇
  2002年   16篇
  2001年   20篇
  2000年   17篇
  1999年   17篇
  1998年   3篇
  1997年   8篇
  1996年   1篇
  1995年   2篇
  1994年   4篇
  1993年   2篇
  1992年   6篇
  1990年   3篇
  1989年   5篇
  1988年   4篇
  1987年   2篇
  1986年   1篇
  1985年   4篇
  1984年   3篇
  1983年   8篇
  1981年   4篇
  1980年   2篇
  1979年   1篇
  1978年   3篇
  1977年   2篇
  1976年   2篇
  1973年   2篇
排序方式: 共有799条查询结果,搜索用时 15 毫秒
241.
Abstract:  When scrutinising the literature on EU environmental policy, it becomes apparent that there has been a comprehensive transition in underlying governance ideas during the last two decades. At the core of these changes is the abolition of traditional patterns of interventionist command-and-control regulation in favour of economic instruments and 'context-oriented' governance. In view of these developments, this article has two objectives: first, it looks into which causes and factors initiated these discussions; second, it analyses the effects these reform ideas had on actual patterns of governance. As will be shown, changes in governance ideas are only partially expressed in changes in policy instruments.  相似文献   
242.
Rat cardiac myocytes were isolated by heart perfusion in the presence of collagenase and incubated in the absence or presence of oxygen. As a result of anoxia, there was a gradual increase in plasma membrane permeability, noted as a decrease in trypan blue exclusion frequency, leakage of cytosolic lactate dehydrogenase and intracellular accumulation of the isotope compound 99Tcm-gluconate. The changes in plasma membrane permeability properties were preceded by a marked decrease in cellular ATP level and an increased proportion of contracted myocytes. The ability of the myocytes to resynthesize ATP and to recover from the anoxic injury upon reoxygenation decreased gradually with the length of initial anaerobic incubation during the first 25 min and disappeared after 30 min of anoxia, indicating that the anoxic injury to the isolated rat cardiac myocytes becomes irreversible after 25 – 30 min of anoxia. It is suggested that a decreased energy level is of primary importance for the initiation of cell injury in anoxia and that it is followed by cell contracture and subsequently by a disturbed plasma membrane function, cell swelling and death. This experimental model system of isolated viable rat cardiac myocytes is suitable for problems dealing with reversibility of myocytic injury.  相似文献   
243.
244.
245.
246.
A GC/MS-method is described for the screening, detection and determination of the commonly used drugs amphetamine, methamphetamine, MDA, MDMA and MBDB in small blood samples and bloodstains using solid phase SPE columns and a pipetting robot (Gilson Aspec XL). The detection limits are in the order of 0.03 to 0.08 microgram/L and the correlation factors between 0.9982 and 0.9998. Furthermore the stability was investigated covering a storage time of 64 days. The method has proven useful in forensic cases with only small sample volumes or bloodstains.  相似文献   
247.
Population frequency data for nine short tandem repeats (STR) (D3S1358, VWA, FGA, TH01, TPOX, CSF1PO, D5S818, D13S317 and D7S820) were determined from 280 unrelated Caucasians from the North region of Belgium (Flanders). The data were obtained using the AmpF/STR Profiler kit from Applied Biosystems.  相似文献   
248.
In a final inquiry at the end of the Conference on Editorial Policies the three editors, Bruno S. Frey (Kyklos), Manfred J. Holler (Homo oeconomicus), and Jürgen G. Backhaus (European Journal of Law and Economics), were asked to comment on their editorial policies. They answered by explaining the challenges they were or still are confronted with, which strategies they have already developed to go on and of course what they have learnt from the deliberations at this conference. In their statements they referred to their preceding paper presentations, and the contributions by Wolfgang Bergsdorf, who is the chief editor of Die Politische Meinung, and Peter Senn.  相似文献   
249.
The author comments on Erik S. Reinert’s presentation held at the 17{th} Heilbronn Symposion in Economics and the Social Sciences in June 2004.  相似文献   
250.
The purpose of this study was to investigate all child homicides for the 25-year period, 1970-1994 in Finland and to analyse the specific characteristics of the filicide cases. A total of 292 child homicides occurred during this period. In 201 (69%) cases the offender was a parent or a stepparent of the child. Altogether, 173 (59%) of the victims were boys and 119 (41%) were girls. For the closer examination of the filicide cases we excluded the neonaticide and homicide-suicide cases. Consequently, we report on 70 filicide victims. Of these victims, 42 (60%) were boys and 28 (40%) were girls. Twenty six (37%) of the children were killed before the age of 1 year and 53 (79%) before the age of 5 years. The offender was the mother in 43 (61%) cases and the father or the stepfather in 26 (37%) cases. The victims of the mothers were younger than those of the fathers. The most frequent causes of death were head injuries, drowning and suffocation. The most common means of assault were battering, drowning and strangulation. One in two of the fatally battered children had a documented history of previous abuse.  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