全文获取类型
收费全文 | 1130篇 |
免费 | 34篇 |
专业分类
各国政治 | 94篇 |
工人农民 | 39篇 |
世界政治 | 94篇 |
外交国际关系 | 76篇 |
法律 | 474篇 |
中国政治 | 11篇 |
政治理论 | 371篇 |
综合类 | 5篇 |
出版年
2023年 | 8篇 |
2021年 | 5篇 |
2020年 | 13篇 |
2019年 | 28篇 |
2018年 | 31篇 |
2017年 | 38篇 |
2016年 | 36篇 |
2015年 | 20篇 |
2014年 | 26篇 |
2013年 | 219篇 |
2012年 | 29篇 |
2011年 | 27篇 |
2010年 | 25篇 |
2009年 | 34篇 |
2008年 | 39篇 |
2007年 | 29篇 |
2006年 | 34篇 |
2005年 | 29篇 |
2004年 | 39篇 |
2003年 | 31篇 |
2002年 | 28篇 |
2001年 | 29篇 |
2000年 | 22篇 |
1999年 | 21篇 |
1998年 | 19篇 |
1997年 | 22篇 |
1996年 | 15篇 |
1995年 | 20篇 |
1994年 | 18篇 |
1993年 | 22篇 |
1992年 | 16篇 |
1991年 | 14篇 |
1990年 | 15篇 |
1989年 | 15篇 |
1988年 | 15篇 |
1987年 | 15篇 |
1986年 | 15篇 |
1985年 | 13篇 |
1984年 | 11篇 |
1983年 | 8篇 |
1982年 | 9篇 |
1981年 | 6篇 |
1979年 | 5篇 |
1978年 | 7篇 |
1976年 | 3篇 |
1975年 | 4篇 |
1974年 | 7篇 |
1972年 | 3篇 |
1969年 | 5篇 |
1968年 | 4篇 |
排序方式: 共有1164条查询结果,搜索用时 0 毫秒
141.
Philip Gleason 《Journal of policy analysis and management》2008,27(1):82-103
Under the policy of direct certification for free school meals, school districts use information shared by state agencies about household eligibility for means‐tested programs in the state in order to determine the potential eligibility for free meals of students enrolled in the district. This information allows districts to automatically approve students in these eligible households for free meals without requiring the household to complete the application process. This paper examines the impacts of direct certification on students' likelihood of becoming certified for free meals, using data from a national survey of school food service directors as well as statelevel administrative data on program participation. A state‐level fixed effects model is estimated to account for the possibility of selection bias. The key finding is that direct certification leads to a statistically significant increase in the number of children getting free school meals. More generally, this finding highlights a promising approach for improving access to means‐tested programs without compromising program integrity. © 2008 by the Association for Public Policy Analysis and Management. 相似文献
142.
Daniel J. Bell 《Journal of criminal justice》1985,13(6):525-534
The data presented here are consistent with prior research conclusions and indicate that wives have been victims in domestic dispute incidents in the United States more frequently than other family or household members. Further, in specific instances where criminal complaints were initiated, it is shown that in these instances, arrest under the Domestic Violence Program produced the strongest association when wives were the victims. The police were likely to arrest offenders (1) when criminal complaints were initiated and (2) when intimate family members, rather than strangers, were victims. The data indicate that victims who did not initiate criminal complaints did not receive adequate protection or services from the criminal justice system, and criminal complaints initiated by wives received significantly more arrest-and-referral activity than did complaints initiated by other family or household members. 相似文献
143.
Histopathological changes in selenium-exposed fish 总被引:1,自引:0,他引:1
E M Sorensen J S Bell C W Harlan 《The American journal of forensic medicine and pathology》1983,4(2):111-123
Redear sunfish (Lepomis microlophus) were collected from Martin Lake in east Texas. For at least 8 months, 1 year earlier, aqueous selenium-laden effluent from man-made sources was released into this 5,000-acre reservoir (unpublished data). Redear sunfish from a reference lake, 8 km upstream, were collected for comparison to Martin Lake fish. The hepatopancreas (i.e., liver and associated, disseminated exocrine pancrease), mesonephros (i.e., kidney), gonads, heart, spleen, stomach, and gill arches were preserved for histopathological examination using optical and/or transmission electron microscopy. Livers from Martin Lake redear sunfish (which had accumulated approximately 20 ppm selenium in the liver) showed central necrosis, reduced quantities of rough endoplasmic reticulum and glycogen particles, and increased numbers of lysosome-like structures. Kidneys showed proliferative glomerulonephritis, and exocrine pancreas showed marked hypertrophy at the optical level. Ultrastructurally, architectural disorganization, reduced rough endoplasmic reticulum, increased cisternal space, and proliferation of smooth endoplasmic reticulum were evident. The stomach, spleen, gill, heart, and gonads showed no abnormalities. 相似文献
144.
145.
Philip Hanson 《欧亚研究》1984,36(4):571-581
146.
147.
148.
149.
150.