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   6315篇
  免费   158篇
  国内免费   3篇
管理学   986篇
民族学   54篇
人才学   9篇
人口学   499篇
丛书文集   47篇
理论方法论   770篇
综合类   51篇
社会学   3260篇
统计学   800篇
  2023年   38篇
  2022年   29篇
  2021年   47篇
  2020年   113篇
  2019年   163篇
  2018年   195篇
  2017年   199篇
  2016年   202篇
  2015年   142篇
  2014年   163篇
  2013年   994篇
  2012年   222篇
  2011年   241篇
  2010年   188篇
  2009年   155篇
  2008年   191篇
  2007年   216篇
  2006年   198篇
  2005年   222篇
  2004年   193篇
  2003年   169篇
  2002年   167篇
  2001年   113篇
  2000年   150篇
  1999年   122篇
  1998年   110篇
  1997年   103篇
  1996年   94篇
  1995年   83篇
  1994年   107篇
  1993年   90篇
  1992年   96篇
  1991年   64篇
  1990年   55篇
  1989年   56篇
  1988年   68篇
  1987年   52篇
  1986年   47篇
  1985年   56篇
  1984年   67篇
  1983年   54篇
  1982年   58篇
  1981年   50篇
  1980年   51篇
  1979年   44篇
  1978年   32篇
  1977年   31篇
  1976年   46篇
  1975年   26篇
  1974年   35篇
排序方式: 共有6476条查询结果,搜索用时 15 毫秒
991.
ABSTRACT

The circular economy (CE) has become a matter of urban development. A literature review shows that the CE debate is biased toward technology-driven industrial change, while bracketing broader socio-political interests. We address this gap by exploring the political economy of scale of the CE. Looking into the case of Brussels (Belgium), a city that has recently adopted the CE as part of its socio-economic strategy, we explore how the anticipated transition to a ‘circular city’ chimes with long-standing urban development agendas. While there is little evidence of stable growth coalitions between corporate and political elites, we argue that the CE provides an ‘urban sustainability fix’ by selectively incorporating ecological goals in urban governance strategies. We further scrutinise the landscape of diverse and heterogenous CE practices in food and transport, highlighting how they are regulated and organised, what labour conditions they offer, and how they are anchored in urban space.  相似文献   
992.
993.
Abstract

Objective: The purpose of this study was to explore differences in oral health among students by military service status in postsecondary settings. Participants: Secondary data were obtained from the American College Health Association’s 2011–2014 National College Health Assessment II. Method: Demographic characteristics of the study sample were explored by calculating frequencies and percentages by military service status. Research questions were explored with maximum likelihood multiple logistic regression. Results: Service member and veteran students are at greater risk for neglecting health behaviors associated with positive oral health, including that they were less likely to get dental exams and that those who deployed in the past were the least likely to be practicing good oral health. Conclusions: The results suggest that improving oral health will contribute to improving health and mental health outcomes in this population, and provide important information for health specialists working with service members and veterans on college campuses.  相似文献   
994.
Abstract

Directionality can be seen in many stationary time series from various disciplines, but it is overlooked when fitting linear models with Gaussian errors. Moreover, we cannot rely on distinguishing directionality by comparing a plot of a time series in time order with a plot in reverse time order. In general, a statistical measure is required to detect and quantify directionality. There are several quite different qualitative forms of directionality, and we distinguish: rapid rises followed by slow recessions; rapid increases and rapid decreases from the mean followed by slow recovery toward the mean; directionality above or below some threshold; and intermittent directionality. The first objective is to develop a suite of statistical measures that will detect directionality and help classify its nature. The second objective is to demonstrate the potential benefits of detecting directionality. We consider applications from business, environmental science, finance, and medicine. Time series data are collected from many processes, both natural and anthropogenic, by a wide range of organizations, and directionality can easily be monitored as part of routine analysis. We suggest that doing so may provide new insights to the processes.  相似文献   
995.
996.
ABSTRACT

The objective of this study is to identify the factors that contribute to the successful or unsuccessful integration of the Chinese diaspora in France. There is already a significant amount of literature that probes into the immigrant experiences of various other groups in France. However, the Chinese diaspora in France has remained insufficiently studied. This study aims to address this gap. The main findings of this study are that 1) unsurprisingly, the older the age of arrival, the less well integrated immigrants are in French society, 2) somewhat surprisingly, the less well integrated an immigrant is, the more likely he or she is going to believe that France is a tolerant and open-minded country, and 3) counterintuitively, the more deeply a member of the Chinese diaspora is immersed in French society, the more likely he or she is going to believe that France is hostile to people of Asian heritage.  相似文献   
997.
Developing family treatments for patients with severe and persistent psychiatric disorder begins at the basic research level, through identifying psychosocial variables that have prognostic significance. Treatment protocols informed by this basic research can then be designed, manualized, and piloted. Next, the efficacy of a new treatment is examined, first in a randomized trial and then, if successful, in a community effectiveness study. We describe this treatment development pathway in a population for whom family attributes have prognostic importance: patients with bipolar affective ddisorder. The methodological complexities of psychosocial treatment studies are many. Moreover, the results of these studies often reflect interactions between treatment, process, and outcome variables.  相似文献   
998.
Consumer Sovereignty and Quasi-Market Failure   总被引:2,自引:0,他引:2  
  相似文献   
999.
Injection drug users are at high risk for homelessness and human immunodeficiency virus (HIV) infection. This study sought to examine incidence rates and the social and economic antecedents of homelessness of impoverished inner-city injection drug users. Of the 569 participants, from a nontreatment sample who participated HIV prevention study, interviewed at baseline, 324 (57%) were reinterviewed 5.2 months later. At baseline 48% of the participants reported that they had been homeless in the past 10 years. Of the 324, 18% reported that at both interviews they had been homeless within the prior 6 months, 12% reported homelessness at baseline but not at follow-up, and 8% reported homelessness at follow-up but not at baseline. At baseline personal social support network characteristic of size of material aid and size of sex network was found to be associated with self-reports of homelessness. Baseline reports of presence of mother in personal network, size of material aid network, and network density were found to be associated with reports of homelessness at follow-up. These result suggest the need for alternative approaches to addressing issues of homelessness injection drug users.  相似文献   
1000.
The North American Free Trade Agreement (NAFTA) and the General Agreement on Tariffs and Trade (GATT) have focused attention on risk assessment of potential insect, weed, and animal pests and diseases of livestock. These risks have traditionally been addressed through quarantine protocols ranging from limits on the geographical areas from which a product may originate, postharvest disinfestation procedures like fumigation, and inspections at points of export and import, to outright bans. To ensure that plant and animal protection measures are not used as nontariff trade barriers, GATT and NAFTA require pest risk analysis (PRA) to support quarantine decisions. The increased emphasis on PRA has spurred multiple efforts at the national and international level to design frameworks for the conduct of these analyses. As approaches to pest risk analysis proliferate, and the importance of the analyses grows, concerns have arisen about the scientific and technical conduct of pest risk analysis. In January of 1997, the Harvard Center for Risk Analysis (HCRA) held an invitation-only workshop in Washington, D.C. to bring experts in risk analysis and pest characterization together to develop general principles for pest risk analysis. Workshop participants examined current frameworks for PRA, discussed strengths and weaknesses of the approaches, and formulated principles, based on years of experience with risk analysis in other setting and knowledge of the issues specific to analysis of pests. The principles developed highlight the both the similarities of pest risk analysis to other forms of risk analysis, and its unique attributes.  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