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   6118篇
  免费   141篇
各国政治   302篇
工人农民   233篇
世界政治   476篇
外交国际关系   218篇
法律   3856篇
中国政治   61篇
政治理论   1095篇
综合类   18篇
  2024年   41篇
  2023年   165篇
  2021年   76篇
  2020年   82篇
  2019年   117篇
  2018年   148篇
  2017年   135篇
  2016年   136篇
  2015年   77篇
  2014年   121篇
  2013年   610篇
  2012年   152篇
  2011年   161篇
  2010年   135篇
  2009年   150篇
  2008年   173篇
  2007年   156篇
  2006年   143篇
  2005年   130篇
  2004年   156篇
  2003年   123篇
  2002年   100篇
  2001年   311篇
  2000年   278篇
  1999年   193篇
  1998年   80篇
  1997年   81篇
  1996年   52篇
  1995年   54篇
  1994年   48篇
  1993年   38篇
  1992年   121篇
  1991年   142篇
  1990年   131篇
  1989年   127篇
  1988年   113篇
  1987年   125篇
  1986年   100篇
  1985年   95篇
  1984年   97篇
  1983年   84篇
  1982年   57篇
  1981年   73篇
  1979年   73篇
  1978年   43篇
  1975年   37篇
  1974年   49篇
  1973年   54篇
  1972年   39篇
  1971年   34篇
排序方式: 共有6259条查询结果,搜索用时 15 毫秒
21.
Drawing on the strategic surprise, warning-response, and foreign policy literature, this article argues that the September 11 terror attacks should be regarded as a strategic surprise and examines a number of key factors that contributed to vulnerability and inhibited vigilance. Three broad explanatory "cuts" derived from the literature—psychological, bureau-organizational, and agenda-political—are deployed to sift through the rapidly expanding empirical record in an effort to shed light on the processes and contextual factors that left the United States vulnerable to the attacks. The article aims to improve our understanding of generic processes and practices that enhance or detract from vulnerability and vigilance.  相似文献   
22.
Decomposition studies were conducted using two carcasses of domestic pigs, Sus scrofa L., 8.4 kg and 15.1 kg in weight, to determine the effects of carcass size on the rate of decomposition, composition of the arthropod fauna, and succession patterns. A total of 46 arthropod taxa were recovered during this study. No size-related differences were observed between carcasses with respect to composition of the arthropod fauna or patterns of succession. A greater number of arthropods were observed attracted to the 15.1-kg carcass, and the rate of decomposition observed was more rapid for the 15.1-kg carcass than for the 8.4-kg carcass. Internal temperatures of the 8.4-kg carcass were more directly related to external ambient temperatures during the fresh and bloated stages of decomposition. During the decay stage, both carcasses generated internal temperatures significantly above ambient temperatures. Following this stage, internal temperatures fell to approximate ambient temperatures during the postdecay and remains stages.  相似文献   
23.
24.
Banks are “special” financial institutions generating distinct corporate governance challenges. The present paper examines the relationship between two of the most pertinent corporate governance factors—that is, the size of the Board of Directors and the proportion of non-executive directors—and firm performance on a sample of 58 large European banks over the period 2002–2004. The empirical analysis embraces a number of bank-specific variables. Our results reveal that bank profitability is negatively related to the size of the Board of Directors, while the impact of Board composition, although positive in all models, is, in most cases, insignificant. The results are robust after controlling for firm-specific variables.   相似文献   
25.
Klagen gegen einen internationalen Sportverband, die auf Feststellung der Unwirksamkeit einer Sperre eines bei einem nationalen Sportverband besch?ftigten Trainers von Wettbewerben dieses Sportverbandes und auf Unterlassung von Handlungen, die eine Akkreditierung verhindern bzw erschweren, gerichtet sind, unterliegen der ausschlie?lichen inl?ndischen Gerichtsbarkeit des Sitzstaates; eine Verbindung solcher Klagen mit einer gegen den nationalen Verband gerichteten gleichartigen Klage ist daher unzul?ssig. – Eine damit zusammenh?ngende Schadenersatzklage gegen den internationalen Verband steht auch nicht in dem von Art 6 Nr 1 LGVü geforderten Zusammenhang mit einer Klage gegen den nationalen Verband wegen Aufl?sung des Trainervertrages aufgrund der Sperre.  相似文献   
26.
27.
A simple and sensitive method is described for quantitative analysis of chlorpromazine in blood, serum, urine and tissue homogenate. The chlorpromazine cation radical produced by adding perchloric acid and 2,3-dichloro-5,6-dicyano-p-benzoquinone to the sample can be detected by the ESR method at room temperature. The sensitivity limit is 10 ng, that is, 20 μl of the solution containing 0.5 μg chlorpromazine/ml. The time needed for the measurement is within 10 min. The chlorpromazine radical thus produced is very stable; for example, 95% of the radical was observed after 24 h. The advantage of this method is discussed by comparing with the ordinary spectrophotometry which requires the purification of the sample.  相似文献   
28.
To demonstrate that norms have independent causal power, constructivists de-emphasise material factors related to state interests and highlight social factors. Similarly, they conceptualise international organisations as autonomous from state influence, and focus on cases featuring non-state actors that stimulate a “tipping point” of norm diffusion among states in advance of state sponsorship. By contrast, this article utilises an historical materialist approach that admits both social and material data to examine the contrasting case of population control. It finds that US corporate foundations, eugenist demographers, feminist birth control activists and related NGOs conceptualised and promoted population control in the United States, at the United Nations, and across developing countries. However, the tipping point of norm diffusion occurred only after the United States publicly advocated population control. Indeed, material and social factors were inextricably bound together.  相似文献   
29.
Esophageal and tracheal fistulas, which occur in 0.05% of medicolegal autopsies, were demonstrated in three cases by a postmortem radiographic technique using silicone rubber/lead oxide as a contrasting medium that vulcanizes at room temperature. In one 83-year-old male, a tracheoesophageal fistula was detected, which had developed after surgical repair of an esophageal rupture caused by a flexible fiberoptic endoscope. In a second case, carcinoma of the esophagus in a 78-year-old male had eroded the trachea and arcus of the aorta creating a fatal tracheoesophagoaortic fistula. In a third case, 55-year-old female developed a tracheobrachicephalic artery fistula as a result of an infiltrating cystic adenocarcinoma of the trachea, resulting in a fatal hemorrhage into the trachea. The results of this study indicate that diagnostic radiologic methods using a vulcanized contrasting medium are useful in supplementing normal dissection in autopsy cases with suspected fistulas of the esophagus or trachea.  相似文献   
30.
We investigated the differences in the levels of carboxyhemoglobin (COHb), cyanide (HCN) and petroleum fuels (gasoline and kerosene) between left and right ventricular bloods from fire victims. COHb was slightly, and HCN and petroleum fuels were markedly higher levels in the left than those in the right. These effects were so called 'first pass phenomena' due to the circulation, diffusion and metabolization before the deaths of fire victims.  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