全文获取类型
收费全文 | 10713篇 |
免费 | 322篇 |
专业分类
各国政治 | 329篇 |
工人农民 | 536篇 |
世界政治 | 651篇 |
外交国际关系 | 340篇 |
法律 | 6786篇 |
中国共产党 | 34篇 |
中国政治 | 134篇 |
政治理论 | 2082篇 |
综合类 | 143篇 |
出版年
2021年 | 67篇 |
2020年 | 154篇 |
2019年 | 143篇 |
2018年 | 218篇 |
2017年 | 260篇 |
2016年 | 294篇 |
2015年 | 242篇 |
2014年 | 238篇 |
2013年 | 915篇 |
2012年 | 256篇 |
2011年 | 296篇 |
2010年 | 222篇 |
2009年 | 291篇 |
2008年 | 348篇 |
2007年 | 370篇 |
2006年 | 344篇 |
2005年 | 317篇 |
2004年 | 310篇 |
2003年 | 256篇 |
2002年 | 253篇 |
2001年 | 363篇 |
2000年 | 335篇 |
1999年 | 267篇 |
1998年 | 165篇 |
1997年 | 121篇 |
1996年 | 144篇 |
1995年 | 119篇 |
1994年 | 141篇 |
1993年 | 128篇 |
1992年 | 201篇 |
1991年 | 253篇 |
1990年 | 226篇 |
1989年 | 203篇 |
1988年 | 228篇 |
1987年 | 206篇 |
1986年 | 227篇 |
1985年 | 200篇 |
1984年 | 171篇 |
1983年 | 163篇 |
1982年 | 110篇 |
1981年 | 127篇 |
1980年 | 102篇 |
1979年 | 107篇 |
1978年 | 92篇 |
1977年 | 82篇 |
1976年 | 66篇 |
1975年 | 69篇 |
1974年 | 68篇 |
1973年 | 79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.
Among the more recognizable programs related to natural and sustainable food is the United States Department of Agriculture’s National Organic Program. Although the robustness of the organic food market is difficult to contest, many debate the extent to which U.S. organic policy outcomes adequately serve consumers and the organic agriculture producers they rely on. This paper engages the debate from the perspective of certified organic producers. Drawing on the results of a nationwide survey of USDA‐certified producers, we first provide a snapshot of how producers assess the environmental, consumer, and market impacts of U.S. organic food policy. We then examine the extent to which organic producers’ policy impact perceptions are associated with their alignment with an “organic ethos”—understood as producers’ commitment to core organic principles and the organic movement. The paper highlights producers’ values as perceptual filters and cognitive mechanisms that help shape producers’ policy impacts perceptions, illustrating a contributing factor to the enduring nature of organic policy debates. 相似文献
993.
L. GUBAREVA 《北京周报(英文版)》2011,54(23):47
<正>The ground was shaking.The roads were distorted.The mountains collapsed,raining down stones.A devastating earthquake ravaged Sichuan Province on May 12,2008,followed by more than 30,000 aftershocks. 相似文献
994.
Journal of Family Violence - This article explores the use of cognitive interviewing among one sensitive population, survivors of crime, and shares lessons learned from a cognitive interviewing... 相似文献
995.
Sara Uhnoo Cecilia Hansen Löfstrand 《Journal of Scandinavian Studies in Criminology & Crime Prevention》2018,19(1):41-60
Many Western-style democracies have witnessed a general shift in the distribution of crime prevention responsibility, away from the state and increasingly to citizens themselves. Civil society is today more and more often called upon as an additional policing resource. This article explores the phenomenon of voluntary citizen participation in policing in Sweden, based on an analysis of 9280 news-media articles. One state-sanctioned (the Volunteers of the Police) and one autonomous civic (Missing People Sweden) initiative were examined, from their respective start until 2017, to understand the role played by police–citizen partnerships in the establishment and legitimation of voluntary policing forms in Sweden. A high degree of integration between police and volunteer work was found, enabling not only effective citizen participation, but also having an influence on police operations. The more effective and publicly visible the voluntary policing bodies were, the more pressure there was on the police to defend its legitimacy, ally itself with the volunteers and regulate the latter’s activities while holding them responsible for their actions. Arguably, however, with the police–citizen relationship being one of integration and mutual dependence, the division of labour and the accountability of both parties risk becoming blurred or even confused. 相似文献
996.
Abstract: The frontal sinuses are known to be unique to each individual; however, no one has tested the independence of the frontal sinus traits to see if probability analysis through trait combination is a viable method of identifying an individual using the frontal sinuses. This research examines the feasibility of probability trait combination, based on criteria recommended in the literature, and examines two other methods of identification using the frontal sinuses: discrete trait combinations and superimposition pattern matching. This research finds that most sinus traits are dependent upon one another and thus cannot be used in probability combinations. When looking at traits that are independent, this research finds that metric methods are too fraught with potential errors to be useful. Discrete trait combinations do not have a high enough discriminating power to be useful. Only superimposition pattern matching is an effective method of identifying an individual using the frontal sinuses. 相似文献
997.
998.
The intradural sagittal diameter at the second cervical vertebra (SD/C2) of 62 SIDS cases was measured myelographically. This SD/C2 proved to be dependent on body size, body weight, and age. A clear, age-dependent difference is to be found in the primarily narrow spinal canal. This parameter (SD/C2), which is more precisely defined in adults on the basis of clinical, radiological, and autopsical findings is assumed to have the value of 0.5 cm in the first 2 months, 0.6 cm in the third month, and 0.65 cm in the fourth month. The resulting potential danger to infants is dependent upon their position. The SD/C2, was significantly decreased in extension as compared to a neutral posture. With consideration of the primarily narrow spinal canal in the infant, there is, according to our measurements, a potential hazard for the infant in any further, significant shortening of the SD/C2. This is independent of the width of the spinal canal under maximal extension. We found individual cases in which the SD/C2 was decreased by almost 50% from the normal value in neutral position. No correlation was found between the primary width of the spinal canal and the degree of luminal reduction upon extension. 相似文献
999.
The chemical substances of perspiration found in latent fingerprint residue may hold the key for dating latent fingerprints. To study the chemical transformations of these components as a function of time and environment, fingerprint residues from four males and four females were analysed by thin-layer chromatography (TLC) and high performance liquid chromatography (HPLC). Three major and two or three minor components were detected by both methods and the variation in the quantity of the major components with time was observed. 相似文献
1000.