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   14229篇
  免费   377篇
管理学   1911篇
民族学   72篇
人才学   4篇
人口学   1122篇
丛书文集   78篇
教育普及   3篇
理论方法论   1326篇
综合类   136篇
社会学   7524篇
统计学   2430篇
  2023年   76篇
  2021年   74篇
  2020年   193篇
  2019年   294篇
  2018年   306篇
  2017年   434篇
  2016年   327篇
  2015年   255篇
  2014年   328篇
  2013年   2773篇
  2012年   404篇
  2011年   385篇
  2010年   308篇
  2009年   289篇
  2008年   327篇
  2007年   303篇
  2006年   342篇
  2005年   341篇
  2004年   266篇
  2003年   250篇
  2002年   270篇
  2001年   339篇
  2000年   302篇
  1999年   327篇
  1998年   217篇
  1997年   185篇
  1996年   242篇
  1995年   233篇
  1994年   258篇
  1993年   261篇
  1992年   266篇
  1991年   257篇
  1990年   272篇
  1989年   238篇
  1988年   229篇
  1987年   206篇
  1986年   186篇
  1985年   207篇
  1984年   211篇
  1983年   148篇
  1982年   152篇
  1981年   120篇
  1980年   129篇
  1979年   125篇
  1978年   111篇
  1977年   98篇
  1976年   97篇
  1975年   97篇
  1974年   72篇
  1973年   64篇
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
61.
Abstract This study examines the contentions of two recent perspectives on rural economic organization and their implications for poverty. Building from (1) agrarian political economy and (2) the rural restructuring literatures, we present a comparative regional analysis of how farming patterns and other aspects of economic organization differentially affect poverty in rural areas. Data are based on 2,349 nonmetropolitan U.S. counties for the 1970–1980 period. Nonhired labor-dependent, family-operated farming (smaller and larger family farming) has relatively similar cross-regional effects on rural poverty. The effects of industrialized farming are more spatially variant, suggesting that this type of farming is integrated into regional political economies in different ways than are simple commodity units. However, farming patterns have only a small effect on rural poverty relative to other factors, such as the local employment structure, characteristics of the population, and geographic location. The results of this study highlight the need to move beyond the farm sector to understand both the dynamics of this sector and the socioeconomic consequences of rural restructuring. More broadly, the study underscores the importance of testing general sociological relationships under different spatial (e.g., regional) contexts.  相似文献   
62.
The development of the gambling market in the Federal Republic of Germany since the middle of the seventies and data on pathological gamblers seeking help are described. The continuously increasing supply, together with increases in turnover, was followed-with some temporal delay-by an increase in the number of gamblers who sought advice and treatment. Preliminary measures taken by the health authorities as well as some consequences of pathological gambling are discussed.This article is a translation of a German article published in: Deutsche Hauptstelle gegen die Suchtgefahren (1990): Jahrbuch '91 zur Frage der Suchtgefahren. Hamburg: Neuland-Verlag.  相似文献   
63.
64.
Resocialization is pulled out of its structuralist roots and recast into an interactionist framework. Building on a substantive theory of the resocialization experience of becoming an adoptive parent, three theoretical properties of interactionist resocialization are presented. These can be summarized as involving unlearning and relearning some aspects of a core identity; the interpretation and active reconstruction of that identity which has reciprocal effects on all actors involved; and finally, the effects of both situational and trans-situational norms that give shape to the resocialization experience. Suggestions are made for other substantive areas of research that could be used for comparative analysis in order to further refine a formal theory of interactionist resocialization.  相似文献   
65.
Career and personal counseling are inextricably intertwined. Career problems have a strong emotional component. Career indecision and procrastination may be better interpreted as zeteophobia, the fear of career exploration. Trait and factor theory pictures career counseling as unrealistically simplistic and leads neophytes to view it as boring. Training all counselors to integrate career and personal counseling would lead to better service for clients.  相似文献   
66.
67.
In the development of many diseases there are often associated random variables which continuously reflect the progress of a subject towards the final expression of the disease (failure). At any given time these processes, which we call stochastic covariates, may provide information about the current hazard and the remaining time to failure. Likewise, in situations when the specific times of key prior events are not known, such as the time of onset of an occult tumour or the time of infection with HIV-1, it may be possible to identify a stochastic covariate which reveals, indirectly, when the event of interest occurred. The analysis of carcinogenicity trials which involve occult tumours is usually based on the time of death or sacrifice and an indicator of tumour presence for each animal in the experiment. However, the size of an occult tumour observed at the endpoint represents data concerning tumour development which may convey additional information concerning both the tumour incidence rate and the rate of death to which tumour-bearing animals are subject. We develop a stochastic model for tumour growth and suggest different ways in which the effect of this growth on the hazard of failure might be modelled. Using a combined model for tumour growth and additive competing risks of death, we show that if this tumour size information is used, assumptions concerning tumour lethality, the context of observation or multiple sacrifice times are no longer necessary in order to estimate the tumour incidence rate. Parametric estimation based on the method of maximum likelihood is outlined and is applied to simulated data from the combined model. The results of this limited study confirm that use of the stochastic covariate tumour size results in more precise estimation of the incidence rate for occult tumours.  相似文献   
68.
In a recent paper in this journal, Lee, Kapadia and Brock (1980) developed maximum likelihood (ML) methods for estimating the scale parameter of the Rayleigh distribution from doubly censored samples. They reported convergence difficulties in attempting to solve numerically the nonlinear likelihood equation (LE). To mitigate these difficulties, they employed approximations to simplify the LE, but found that the solution of the resulting simplified equation can give rise to parameter estimates of erratic accuracy. We show that the use of approximations to simplify the LE is unnecessary. In fact, under suitable parametric transformation, the log-likelihood function is strictly concave, the ML estimate always exists, is unique and finite. Furthermore, the LE is easy to solve numerically. A numerical example is given to illustrate the computations involved.  相似文献   
69.
Dental caries in children is now recognized as a preventable disease. The use of fluoride and sealants has produced a major reduction in caries prevalence among school aged children in the United States and other countries. A portion of the child population who are educationally and socioeconomically disadvantaged are not fully receiving these benefits. Public policy, insurance and medicaid groups must be made aware of these preventative measures and strategies developed to implement them.  相似文献   
70.
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