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   1125篇
  免费   39篇
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
  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 390 毫秒
51.
It is becoming increasingly accepted, not least by the Prime Minister and opposition leadership, that the negotiation of a comprehensive trade relationship with the EU is necessary to prevent the UK economy falling off a ‘cliff edge’. This concern is shaping the UK's strategy towards negotiations with the EU and has provided at least part of the motivation for the UK to consider requesting a transition period to facilitate the Brexit process. But how accurate are these fears? What evidence is there for the existence of a ‘cliff edge’? How disastrous would it be for the UK to revert to trading with the EU on the same basis as most other countries in the world, namely according to World Trade Organisation rules? This article seeks to address these issues and it highlights a number of implications for policy makers which flow from understanding the available evidence a little more clearly.  相似文献   
52.
53.
54.
We evaluate changes in elementary school children health outcomes following the introduction of California's Paid Family Leave (PFL) program, which provided parents with paid time off following the birth of a child. Our health outcomes—overweight, ADHD, and hearing‐related problems—are characterized by diagnosis rates that only pick up during early elementary school. Moreover, our health outcomes have been found to be negatively linked with many potential implications of extended maternity leave—increased breastfeeding, prompt medical checkups at infancy, reduced prenatal stress, and reduced non‐parental care during infancy. Using the Early Childhood Longitudinal Studies (ECLS) within a difference‐in‐differences framework, our results suggest improvements in health outcomes among California elementary school children following PFL's introduction. Furthermore, the improvements are driven by children from less advantaged backgrounds, which is consistent with the notion that California's PFL had the greatest effect on leave‐taking duration after childbirth mostly for less advantaged mothers who previously could not afford to take unpaid leave.  相似文献   
55.
Trade has again emerged as a controversial issue in America, yet we know little about the ideas that guide American thinking on these questions. By combining traditional survey methods with experimental manipulation of problem content, this study explores the ideational landscape among elite Americans and pays particular attention to how elite Americans combine their ideas about commerce with their ideas about national security and social justice. We find that most American leaders think like intuitive neoclassical economists and that only a minority think along intuitive neorealist or Rawlsian lines. Among the mass public, in contrast, a majority make judgments like intuitive neorealists and intuitive Rawlsians. Although elite respondents see international institutions as promising vehicles in principle, in practice they favor exploiting America's advantage in bilateral bargaining power over granting authority to the World Trade Organization. The distribution of these ideas in America is not arrayed neatly along traditional ideological divisions. To understand the ideational landscape, it is necessary to identify how distinctive mentaal models—mercantilist, neorealist, egalitarian, and neoclassical economic—sensitize or desensitize people to particular aspects of geopolitical problems, an approach we call cognitive interactionism.  相似文献   
56.
57.
Friends provide important social contexts for student development. Research has shown that adolescent friends are similar to each other in their interest and values for different school subjects. Yet our current understanding does not extend to knowing whether selection, deselection, or socialization processes are responsible for this phenomena. Without this knowledge, it is very difficult for parents, teachers, and schools to know how and when to intervene. This study investigated selection, deselection, and socialization effects on adolescent students’ task values for academic (languages, math and science, and social sciences) and non-academic subject areas (the arts and physical education). A social network approach was used to examine two waves of annual data collected from school-based networks of adolescents in the first and second years of high school education in Finland (N?=?1419; female?=?48.6%; mean age at first measurement point?=?16). The results revealed that adolescents tended to select friends with similar levels of task values (friend selection) for the arts and physical education, but friends did not become more similar in these areas over time (friend socialization). In contrast, there was evidence of friend socialization, but not friend selection, for the academic school subjects. Across all subjects, differences in task values did not predict friendship dissolution (friend deselection). These findings suggest that to a significant extent, students make agentic choices in developing friendship with schoolmates based on their task values in non-academic subjects. The resultant friend contexts that individuals created, in turn, affected their task values in academic subject areas. These results shed light on the complexity of friend effect mechanisms on task values at the subject domain-specific level.  相似文献   
58.
Two discreet choice experiments investigated how three styles of leadership (i.e., transformational, transactional, and ethical) and three job features aimed at activating different motivational forces (i.e., public service motivation, external regulation, and intrinsic motivation) simultaneously and independently affected the job preferences of a sample of public employees. Subjects displayed a strong preference for jobs that benefit more citizens, that are more interesting, and that require working under ethical leaders rather than unethical ones. Whereas the prospect of a 5% salary increase strengthened participants’ preferences for a given position, offering a 1% salary raise did not significantly change subjects’ job choices. Furthermore, participants did not appear to have any preference for working under a transformational leader rather than a transactional leader.  相似文献   
59.
Are internalizing and externalizing behavior problems interrelated via mutually reinforcing relationships (with each behavior leading to increases over time in levels of the other behavior) or mutually suppressing relationships (with each behavior leading to decreases over time in levels of the other behavior)? Past research on the directionality of these relationships has led to ambiguous results, particularly in adolescence. Furthermore, the extent to which prior results will generalize to adolescents with low levels of cognitive abilities remains unknown. This second limit is particularly important, given that these adolescents are known to present higher levels of externalizing and internalizing behaviors than their peers with average-to-high levels of cognitive abilities, and that the mechanisms involved in the reciprocal relationships between these two types of behaviors may differ across both populations. This study examines the directionality of the longitudinal relationships between externalizing and internalizing behavior problems as rated by teachers across three measurement waves (corresponding to Grades 8–10) in matched samples of 138 adolescents (34.78?% girls) with low levels of cognitive abilities and 556 adolescents (44.88?% girls) with average-to-high levels of cognitive abilities. The results showed that the measurement structure was fully equivalent across time periods and groups of adolescents, revealing high levels of developmental stability in both types of problems, and moderately high levels of cross-sectional associations. Levels of both internalizing and externalizing behaviors were higher among adolescents with low levels of cognitive abilities relative to those with average-to-high levels of cognitive abilities. Finally, the predictive analyses revealed negative reciprocal longitudinal relationships (i.e., mutually suppressing relationships) between externalizing and internalizing problems, a result that was replicated within samples of adolescents with low, and average-to-high levels of cognitive ability.  相似文献   
60.
The past decade has witnessed an intensifying focus on the development of irrigation in sub-Saharan Africa. It follows a 20-year hiatus in the wake of disappointing irrigation performance during the 1970s and 1980s. Persistent low productivity in African agriculture and vulnerability of African food supplies to increasing instability in international commodity markets are driving pan-African agricultural investment initiatives, such as the Comprehensive Africa Agricultural Development Programme (CAADP), that identify as a priority the improvement in reliability of water control for agriculture. The paper argues that, for such initiatives to be effective, there needs to be a re-appraisal of current dynamics of irrigation development in sub-Saharan Africa, particularly with respect to the role of small-scale producers’ initiatives in expanding irrigation. The paper reviews the principal forms such initiatives take and argues that official narratives and statistics on African irrigation often underestimate the extent of such activities. The paper identifies five key characteristics which, it argues, contradict widely held assumptions that inform irrigation policy in Africa. The paper concludes by offering a definition of ‘farmer-led irrigation’ that embraces a range of interaction between producers and commercial, government and non-government agencies, and identifies priority areas for research on the growth potential and impact of such interactions and strategies for their future development.  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