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   17124篇
  免费   290篇
各国政治   662篇
工人农民   1436篇
世界政治   706篇
外交国际关系   564篇
法律   10302篇
中国共产党   3篇
中国政治   59篇
政治理论   3604篇
综合类   78篇
  2020年   117篇
  2019年   152篇
  2018年   1451篇
  2017年   1390篇
  2016年   1211篇
  2015年   220篇
  2014年   173篇
  2013年   1013篇
  2012年   418篇
  2011年   1136篇
  2010年   1177篇
  2009年   778篇
  2008年   982篇
  2007年   918篇
  2006年   274篇
  2005年   290篇
  2004年   407篇
  2003年   356篇
  2002年   253篇
  2001年   279篇
  2000年   279篇
  1999年   198篇
  1998年   130篇
  1997年   140篇
  1996年   133篇
  1995年   131篇
  1994年   121篇
  1993年   117篇
  1992年   188篇
  1991年   205篇
  1990年   183篇
  1989年   182篇
  1988年   165篇
  1987年   185篇
  1986年   178篇
  1985年   165篇
  1984年   168篇
  1983年   174篇
  1982年   104篇
  1981年   93篇
  1980年   77篇
  1979年   113篇
  1978年   86篇
  1977年   83篇
  1976年   60篇
  1975年   60篇
  1974年   66篇
  1973年   74篇
  1972年   64篇
  1968年   53篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
101.
Recent studies point to the potential theoretical and practical benefits of focusing police resources on crime hot spots. However, many scholars have noted that such approaches risk displacing crime or disorder to other places where programs are not in place. Although much attention has been paid to the idea of displacement, methodological problems associated with measuring it have often been overlooked. We try to fill these gaps in measurement and understanding of displacement and the related phenomenon of diffusion of crime control benefits. Our main focus is on immediate spatial displacement or diffusion of crime to areas near the targeted sites of an intervention. Do focused crime prevention efforts at places simply result in a movement of offenders to areas nearby targeted sites—“do they simply move crime around the corner”? Or, conversely, will a crime prevention effort focusing on specific places lead to improvement in areas nearby—what has come to be termed a diffusion of crime control benefits? Our data are drawn from a controlled study of displacement and diffusion in Jersey City, New Jersey. Two sites with substantial street‐level crime and disorder were targeted and carefully monitored during an experimental period. Two neighboring areas were selected as “catchment areas” from which to assess immediate spatial displacement or diffusion. Intensive police interventions were applied to each target site but not to the catchment areas. More than 6,000 20‐minute social observations were conducted in the target and catchment areas. They were supplemented by interviews and ethnographic field observations. Our findings indicate that, at least for crime markets involving drugs and prostitution, crime does not simply move around the corner. Indeed, this study supports the position that the most likely outcome of such focused crime prevention efforts is a diffusion of crime control benefits to nearby areas.  相似文献   
102.
Fragment     
  相似文献   
103.
104.
Presents forensic medical characteristics of the specific features of stabbed and cut injuries of human skin and jersey. Suggests a complex of signs that will help determine some structural parameters of a knife blade and the conditions of its interaction with the injured site of human body.  相似文献   
105.
The impact of high temperatures (24 to 39 degrees C) and low to moderately high humidities (20 to 70%) on the applicability of TLC systems for drug identification was studied during a 6 month climatologic cycle in Burkina Faso (West Africa). In general, the Rf values as observed on the plates were found to be substantially affected as compared with values obtained at temperate climates. Some TLC systems were more affected than others and the largest deviations of up to 30 Rf units were at low humidities. Tropical conditions also had a negative effect on the reproducibility of Rf values. However, when an Rf-correction procedure was applied, using reference mixtures of known drugs on each plate, accuracy as well as reproducibility of the resulting Rfc values were drastically improved and data thus corrected were found to be compatible with existing TLC data bases developed under moderate climatological conditions. The impact of high to extremely high humidities (70 to 100%) remains to be investigated.  相似文献   
106.
Veto Players and Civil War Duration   总被引:1,自引:0,他引:1  
Civil wars show a remarkable variation in how long they last. Some end within days; others continue for decades. What explains the extreme intractability of some wars while others are resolved quickly? This article argues that conflicts with multiple actors who must approve a settlement (veto players) are longer because there are fewer acceptable agreements, information asymmetries are more acute, and shifting alliances and incentives to hold out make negotiation more difficult. This veto player approach to explaining variation in civil war duration is tested using a new dataset containing monthly data on all parties to each civil war begun since World War II. The statistical analysis shows a strong correlation between the number of veto players and the duration of civil war.  相似文献   
107.
In this study, a new method was developed for the impurity profiling of illicit MDMA tablets. The extraction efficiency, linearity, repeatability and reproducibility of the method were evaluated. Eighty two MDMA tablets coming from presumed unrelated large seizures in 2004 (n >500 tablets) were analyzed by gas chromatography mass spectrometry (GC-MS) in order to assess the discrimination power of the method. The latter was found to be practical, robust, relatively easy to perform, highly discriminative and yielding good chromatography. In addition, some new impurities were detected and identified. Their chemical structures and mass spectra are reported.  相似文献   
108.
The increased risk of child maltreatment in the presence of domestic violence is well documented, but much remains unknown about factors that modify this relationship. This study investigates the roles of risk and protective factors in the relationship between domestic violence and being reported to the Department of Social Services for child maltreatment. Consistent with the literature, we find a significant overlap between domestic violence and maltreatment. Young maternal age, low education, low income, and lack of involvement in a religious community add to the risk for maltreatment associated with domestic violence. Separation between the maternal caregiver and her partner significantly reduces the risk for maltreatment when domestic violence is reported. A significant reduction in the risk for maltreatment is also found with higher levels of support from the maternal caregiver reported by the child in the context of domestic violence.  相似文献   
109.
Child custody evaluators with experience in mediation may be tempted to use mediation skills and strategies in their evaluation processes. This article explores the benefits and risks of blending mediation with evaluation, comparing the perspectives of professionals and clients.  相似文献   
110.
In two recent cases, Grutter v. Bollinger, 539 U.S. 306. (2003) and Gratz v. Bollinger, 539 U.S. 244. (2003), the Supreme Court held that the Equal Protection Clause permitted state schools to use race-sensitive admissions in order to obtain the educational benefits that flow from a diverse student body. The diversity-based argument for race-sensitive admissions, scholarships, awards, and other opportunities at universities should have been rejected because it does not consider the full range of costs and benefits and because the more narrow educational effects probably weigh against such programs. However, this does not suggest that applicants’ race, ethnicity, and gender should be ignored. Rather the same consideration that led to the defeat of the diversity argument, i.e., reasoning capacity, supports the consideration of demographic factors. However, attention to such factors further undermines the consequentialist case for affirmative action.  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