全文获取类型
收费全文 | 9137篇 |
免费 | 244篇 |
专业分类
各国政治 | 462篇 |
工人农民 | 271篇 |
世界政治 | 669篇 |
外交国际关系 | 298篇 |
法律 | 5777篇 |
中国政治 | 57篇 |
政治理论 | 1764篇 |
综合类 | 83篇 |
出版年
2020年 | 103篇 |
2019年 | 118篇 |
2018年 | 161篇 |
2017年 | 161篇 |
2016年 | 171篇 |
2015年 | 123篇 |
2014年 | 144篇 |
2013年 | 901篇 |
2012年 | 197篇 |
2011年 | 222篇 |
2010年 | 182篇 |
2009年 | 180篇 |
2008年 | 208篇 |
2007年 | 224篇 |
2006年 | 244篇 |
2005年 | 225篇 |
2004年 | 214篇 |
2003年 | 227篇 |
2002年 | 217篇 |
2001年 | 360篇 |
2000年 | 297篇 |
1999年 | 227篇 |
1998年 | 120篇 |
1997年 | 108篇 |
1996年 | 86篇 |
1995年 | 92篇 |
1994年 | 94篇 |
1993年 | 99篇 |
1992年 | 173篇 |
1991年 | 212篇 |
1990年 | 187篇 |
1989年 | 225篇 |
1988年 | 209篇 |
1987年 | 220篇 |
1986年 | 213篇 |
1985年 | 205篇 |
1984年 | 168篇 |
1983年 | 174篇 |
1982年 | 117篇 |
1981年 | 123篇 |
1980年 | 101篇 |
1979年 | 122篇 |
1978年 | 95篇 |
1977年 | 84篇 |
1976年 | 85篇 |
1975年 | 92篇 |
1974年 | 98篇 |
1973年 | 96篇 |
1972年 | 87篇 |
1969年 | 79篇 |
排序方式: 共有9381条查询结果,搜索用时 15 毫秒
51.
Federal transportation officials assert that labor protections in the Urban Mass Transportation Act inhibit the propensity of local transit agencies to contract with private firms for services. The authors present results from a survey of a large sample of transit managers and econometric analysis to support their conclusion that labor protections do not appear to reduce the incidence of contracting. The labor protections, however, may be costly to transit management in other ways. The authors recommend actions, aside from repeal of labor protections, to increase contracting by local transit agencies. 相似文献
52.
The concentration of thyreoglobulin (tg) was determined for death caused by hanging, strangulation by ligature, and throttling. Cases of sudden death (traumatic aortic rupture, penetrating wounds of the heart) were used for comparison. The mean values in cases of hanging (149.9±202.3 ng/ml), strangulation by ligature (193.1±173.3), manual strangulation (561.6±173.9) are distinguishable from violent acute deaths (23.3±27.6) and living healthy individuals (17.3±16.1). By means of statistical comparisons, significant differences were found between throttling and strangulation by ligature and between throttling and hanging (adjusted P<0.001). In connection with examination of the bodies high tg values can be regarded as a vital reaction in obstructive asphyxia. 相似文献
53.
A growing body of evidence shows that minorities are disproportionately the targets of police brutality, but important theoretical questions about the causes of that inequity remain unanswered. One promising line of research involves structural‐level analyses of the incidence of police brutality complaints; however, existing studies do not incorporate variables from alternative theoretical explanations. Drawing on the community accountability hypothesis and the threat hypothesis, we tested the predictions of two prominent structural‐level explanations of police brutality in a study of civil rights criminal complaints. The study included cities of 150,000+ population (n = 114). The findings reveal that two community accountability variables—ratio percent Hispanic citizens to percent Hispanic police officers and the presence of citizen review—were related positively to police brutality complaints, partially supporting that perspective. Two threat hypothesis measures of threatening people—percent black and percent Hispanic (in the Southwest)—were related positively to complaints, as predicted. The relative degree of support for the two hypotheses is assessed. 相似文献
54.
A number of recent studies have explored the consequences ofinterracial peer effects on the academic and social performanceof minority students. This article contributes to that discussion,focusing, however, on perceptions rather than behaviors. Theanalysis suggests that exposure to white peers is associatedwith declining perceptions of racial justice among black andLatino high school students. While cautioning against causalinterpretations of this finding, the article suggests that theintegrationist aims of Brown v. Board of Education will notbe satisfied without more thoughtful and vigorous desegregationefforts. 相似文献
55.
Some features of early child care are more prominent in Norway than in other countries, such as emphasis on the outdoor environment. Of general relevance and interest is the form of day care provided by forest day-care centers. Three ideas form the development of these centers placed in wild areas. First, throughout history, Norwegians have had a close attachment to nature and some parents want to provide their children with outdoor experiences at an early age. Second, urging children to play outdoors characterizes the image many parents have of a happy, healthy childhood. Third, provision of day care for children has always been restricted in western countries, forcing parents to invent types of service that can become part of an ecological system that promotes healthy development.The forest day-care centers developed recently represent a supplement to the wide typology of child care in the 21st century. The article outlines the connections between these ideas in general European and western history and Norwegian history and presents debate and decisions about a question dating from the last half of the 1980s. It concludes that the forest day-care centers are perhaps only a modern form of the original kindergarten concept, which started in Europe and America as gardens for children not gardens of children. 相似文献
56.
57.
Andrew M. Greeley is a priest, sociologist, novelist, and journalist. His scholarly writings concentrate on religion and ethnicity.
His other writings range from critiques of the Catholic church to best-selling novels. 相似文献
58.
59.
A report of an international collaborative experiment to demonstrate the uniformity obtainable using DNA profiling techniques. 总被引:2,自引:0,他引:2
P Gill S Woodroffe W B?r B Brinkmann A Carracedo B Eriksen S Jones A D Kloosterman B Ludes B Mevag 《Forensic science international》1992,53(1):29-43
This paper describes a collaborative exercise intended to demonstrate whether uniformity of DNA profile results could be achieved between different European laboratories. It was shown that this goal can be obtained provided that a common protocol is followed (specifically the use of a common electrophoretic buffer as being the most important parameter). Generally, lower molecular weight loci (with lower molecular weight fragments) such as YNH24 perform better than higher molecular weight loci such as MS43a. The results of the exercise are discussed in relation to the objectives of the European DNA profiling group (EDNAP). 相似文献
60.