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   26318篇
  免费   759篇
  国内免费   2篇
管理学   3506篇
民族学   138篇
人口学   2340篇
丛书文集   105篇
教育普及   1篇
理论方法论   2348篇
综合类   301篇
社会学   12964篇
统计学   5376篇
  2023年   163篇
  2021年   155篇
  2020年   434篇
  2019年   648篇
  2018年   732篇
  2017年   999篇
  2016年   740篇
  2015年   531篇
  2014年   715篇
  2013年   4734篇
  2012年   919篇
  2011年   848篇
  2010年   656篇
  2009年   541篇
  2008年   726篇
  2007年   671篇
  2006年   678篇
  2005年   539篇
  2004年   539篇
  2003年   454篇
  2002年   494篇
  2001年   617篇
  2000年   550篇
  1999年   529篇
  1998年   419篇
  1997年   376篇
  1996年   386篇
  1995年   385篇
  1994年   323篇
  1993年   368篇
  1992年   415篇
  1991年   397篇
  1990年   399篇
  1989年   342篇
  1988年   338篇
  1987年   301篇
  1986年   316篇
  1985年   324篇
  1984年   321篇
  1983年   280篇
  1982年   244篇
  1981年   185篇
  1980年   239篇
  1979年   266篇
  1978年   200篇
  1977年   184篇
  1976年   154篇
  1975年   175篇
  1974年   154篇
  1972年   121篇
排序方式: 共有10000条查询结果,搜索用时 109 毫秒
31.
The histories and service needs of 2 groups of homeless women, those unaccompanied by minor children (n = 46) and those accompanied by minor children (n = 22), were compared, on the basis of their responses to a biennial survey of homeless people in a midsize city in the southeast United States. Mothers of children aged 2–10 also completed a measure of stress symptoms for their children (n = 20). Irrespective of family status group, problems such as substance abuse, history of mental illness, health problems, chronicity of homelessness, and crime victimization tended to cluster together. The findings also suggest that declining and/or inadequate levels of public benefits, Temporary Assistance to Needy Families, and Medicaid-funded health care in particular, have adversely affected the 2 groups, particularly families with children. The young children in this sample experienced elevated levels of stress, and significant associations were found between children's stress levels and certain risk factors of their mothers. Implications for service delivery are discussed.  相似文献   
32.
A study sample of 162 six‐month‐old children was selected from a larger sample of 346 infants on the basis of parents' report of their infants' temperament and a laboratory assessment of temperament. Infants were classified as easily frustrated and less easily frustrated and compared on a number of emotion regulation, physiology, and temperament measures. Results indicated that male and female infants were equally likely to be classified as frustrated and less easily frustrated; however, male infants were less able to regulate physiologically. Easily frustrated infants used different emotion regulation strategies and were observed to be less attentive and more active than less easily frustrated infants when observed in the laboratory. These infants were also characterized by their parents as more active, less attentive, and more distressed to novelty. Infants classified as easily frustrated were more reactive physiologically and less able to regulate physiological reactivity than their less easily frustrated counterparts. It is hypothesized that this cluster of characteristics may constitute a unique temperamental type that may have implications for other types of behavioral functioning. Limitations of the study are that observations are based on a single brief assessment of the infant, modest effect sizes were found, and the study is cross‐sectional.  相似文献   
33.
The product of two independent or dependent scalar normal variables, sums of products, sample covariances, and general bilinear forms are considered. Their distributions are shown to belong to a class called generalized Laplacian. A growth-decay mechanism is also shown to produce such a generalized Laplacian. Sets of necessary and sufficient conditions are derived for bilinear forms to belong to this class. As a generalization, the distributions of rectangular matrices associated with multivariate normal random vectors are also discussed.  相似文献   
34.
The simple logistic regression model with normal measurement error and normal regressor is shown to be identifiable without any extra information about the measurement error. The multiple logistic regression model with more than one regressor variable measured with error is not identifiable. If the covariance matrix of the measurement error is known up to a scalar factor, the model is identified. Further we discuss why in spite of the identifiability the models cannot be estimated in a reasonable way without extra information about the measurement error.  相似文献   
35.
36.
What do voters really know about party platforms and how do they perceive the contents? Are there any relationships between party election platforms and electoral behavior? Despite of much research on parties, there are hardly any answers to these questions. If political parties devise programmes in order to influence political attitudes or electoral behavior, it will be necessary that these programmes are read by people. But it seems to be unclear if and how people do so. This article shows clearly that voters don’t know much about party manifestoes. Still, programmes are more important for voters than many people believe. Programmes are also an important factor for electoral behavior. But there is still a lack of data to get evident results.  相似文献   
37.
38.
Using an increasing returns specification for distribution, an inverted U pattern between the share of distribution in gross domestic product and the level of development is shown to arise. A cross-section time-series data set is constructed and merged with one used to analyze the service sector. In contrast to the rising pattern found for services, an average time-series relation that exhibits an inverted U pattern is established. The empirical results are robust, for example, to choice of functional form and country and time period coverage. A similar pattern is found in the average cross-section (country) relation between distribution and development.  相似文献   
39.
40.
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