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   5147篇
  免费   158篇
管理学   718篇
民族学   24篇
人口学   523篇
丛书文集   20篇
教育普及   1篇
理论方法论   491篇
综合类   59篇
社会学   2405篇
统计学   1064篇
  2023年   34篇
  2021年   50篇
  2020年   89篇
  2019年   119篇
  2018年   129篇
  2017年   195篇
  2016年   141篇
  2015年   84篇
  2014年   135篇
  2013年   793篇
  2012年   162篇
  2011年   146篇
  2010年   125篇
  2009年   109篇
  2008年   137篇
  2007年   127篇
  2006年   149篇
  2005年   112篇
  2004年   113篇
  2003年   78篇
  2002年   99篇
  2001年   134篇
  2000年   126篇
  1999年   136篇
  1998年   104篇
  1997年   87篇
  1996年   95篇
  1995年   68篇
  1994年   61篇
  1993年   89篇
  1992年   91篇
  1991年   99篇
  1990年   79篇
  1989年   78篇
  1988年   61篇
  1987年   68篇
  1986年   62篇
  1985年   76篇
  1984年   66篇
  1983年   71篇
  1982年   44篇
  1981年   41篇
  1980年   37篇
  1979年   48篇
  1978年   38篇
  1977年   33篇
  1976年   34篇
  1975年   32篇
  1974年   40篇
  1973年   29篇
排序方式: 共有5305条查询结果,搜索用时 397 毫秒
981.
Summary A re-analysis of Knodel's data provides some new results for the fertility decline in Germany and a new approach to testing hypotheses about the demographic transition. Two formulations of transition theory are compared: one emphasizing the importance of changing social and economic structure for fertility decline; the other, the changing relationships between fertility and its determinants over time. To evaluate these formulations, multivariate time series cross-sectional models are developed. The statistical models permit the estimation of relationships both cross-sectionally and over time. As a consequence, the ability of the independent variables to explain cross-sectional as against temporal differences is evaluated. Industrialization, urbanization, religious composition, migration, infant mortality and marriage patterns satisfactorily explain the fertility decline once regional differences have been taken into account. Persisting characteristics of regional units account for much of the unexplained variance. Industrialization is the main explanatory variable of fertility decline in Germany. In the period considered, its impact on fertility increased substantially.  相似文献   
982.
983.
Abstract Differential growth in the use of oral anovulents is explored through construction of separate time series for Canadian women classified by religion, education, and nativity. The series suggest that native-born Roman Catholic women are as likely as native-born Protestant women to be using oral contraceptives by the terminal point of our series in 1967. The period of very rapid growth in the use of orals appears to have come to an end. Differential patterns of diffusion of oral contraception shown by the categories of women discussed, suggest sources of bias in the profile of an aggregate time series.  相似文献   
984.
Abstract It is assumed that in the long run U.S. population growth will have to cease, as otherwise life will become physically impossible. Various hypothetical possibilities of achieving such a type of development are investigated. Alternatives of reproduction rate trends are considered in terms of alternatives of interactions of assumed age-specific fertility and mortality trends and these are computed and evaluated. The various computations then indicate the nature of childbearing attitudes and behaviour, which the 'average population' would have to adopt in order to achieve the desired stationary population growth after a certain period of time. On the other hand the results presented in the paper also indicate that a certain population growth (of the order of 30-50%) and change in age structure is inevitable in the coming 5-10 decades given the initial childbearing behaviour.  相似文献   
985.
SMPD Scenarios of Spatial Distribution of Human Population in China   总被引:1,自引:0,他引:1  
Three scenarios of spatial distribution of human population in China are developed in the years 2010 and 2020, respectively by means of the method of surface modeling of population distribution (SMPD). Each one of the SMPD scenarios is defined as a plausible alternative future under particular assumptions of elevation, water system, net primary productivity (NPP), urbanization, transport infrastructure development, and population growth. The SMPD scenarios show that if population could freely migrate within the whole China, the balanced ratios of population in the western region, the middle region and the eastern region to total population in the whole China would be 16%, 33% and 52%, respectively.  相似文献   
986.
Empirical research on US immigrants is reviewed: their productivity and assimilation; their contribution and use of public services; and their impact on native Americans. I discuss the characteristics of cohorts of immigrants that enter the United States at different times, and then quantify the assimilation of immigrants, typically in terms of economic productivity of immigrants compared with natives. Few have found quantifiable negative effects of immigrants on native wages or unemployment in local labor markets, but a more general equilibrium approach than has been empirically implemented may be needed to draw any conclusions regarding the distributional consequences of immigration. Received: 22 September 1995 / Accepted: 2 March 1997  相似文献   
987.
Emerging research on methamphetamine use among gay men suggests that growth in the use of this drug could present serious problems for HIV/AIDS prevention within the gay community. This article summarizes current studies on the extent, role, and context of methamphetamine use among gay men and its relationship to high risk sexual behaviors related to HIV transmission. Methamphetamine is often used by gay men to initiate, enhance, and prolong sexual encounters. Use of the drug is, therefore, associated with particular environments where sexual contact among gay men is promoted, such as sex clubs and large "circuit" parties. Research with gay and bisexual men indicates that methamphetamine use is strongly associated with risky sexual behaviors that may transmit HIV. This relationship, coupled with emerging evidence that methamphetamine use is on the rise among gay men, suggests that the drug could exacerbate the HIV/AIDS epidemic among this community. The article offers recommendations for further research and suggestions for prevention programs regarding methamphetamine use by gay men.  相似文献   
988.
This study uses the large, but neglected, body of Indian historical demographic and health data to show that smallpox was a major killer in past times. At the start of the nineteenth century roughly 80 percent of India's population had no effective protection against the disease, and in these circumstances virtually everyone suffered from it in childhood. The main exception was Bengal, where the indigenous practice of inoculation greatly limited the prevalence of the disease. Smallpox case fatality in India was high—around 25–30 percent in unprotected populations—and significantly higher than estimated for unprotected populations in eighteenth-century Europe. Although vaccination reached India in 1802, the practice spread slowly during the first half of the nineteenth century. From the 1870s onward there were considerable improvements in vaccination coverage. The study demonstrates a close link between the spread of vaccination and the decline of smallpox. Whereas at the start of the nineteenth century the disease may have accounted for more than 10 percent of all deaths in India, by the end of the century smallpox had become a comparatively minor cause of death as a result of improved vaccination coverage.  相似文献   
989.
990.
Fiscal impacts of immigration to the United States   总被引:1,自引:0,他引:1  
"The purpose of this paper is to fill a gap in the demographic literature by reviewing previous fiscal studies of immigration in the United States. Each study is introduced by describing the data it uses, the methodologies employed in calculating costs and revenues, and the resulting estimates of fiscal consequences. Evaluative comments are also stressed. Seventeen studies are included in this review, divided into those that emphasize national fiscal impacts (these studies aggregate the effects of immigrants across all levels of government), state fiscal impacts, and fiscal effects on local governments."  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