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   7436篇
  免费   125篇
  国内免费   1篇
管理学   990篇
民族学   33篇
人口学   761篇
丛书文集   33篇
理论方法论   662篇
综合类   90篇
社会学   3581篇
统计学   1412篇
  2023年   40篇
  2020年   97篇
  2019年   141篇
  2018年   168篇
  2017年   253篇
  2016年   178篇
  2015年   124篇
  2014年   161篇
  2013年   1302篇
  2012年   228篇
  2011年   206篇
  2010年   146篇
  2009年   134篇
  2008年   147篇
  2007年   141篇
  2006年   171篇
  2005年   153篇
  2004年   148篇
  2003年   136篇
  2002年   153篇
  2001年   164篇
  2000年   168篇
  1999年   173篇
  1998年   137篇
  1997年   133篇
  1996年   126篇
  1995年   110篇
  1994年   107篇
  1993年   110篇
  1992年   117篇
  1991年   128篇
  1990年   125篇
  1989年   144篇
  1988年   85篇
  1987年   109篇
  1986年   93篇
  1985年   114篇
  1984年   96篇
  1983年   104篇
  1982年   81篇
  1981年   81篇
  1980年   76篇
  1979年   81篇
  1978年   83篇
  1977年   60篇
  1976年   66篇
  1975年   61篇
  1974年   59篇
  1973年   48篇
  1971年   41篇
排序方式: 共有7562条查询结果,搜索用时 15 毫秒
31.
Public and nonprofit organizations need to make strategic choices about where to invest their resources. They also need to expose hidden managerial assumptions and lack of adequate knowledge that prevent the attainment of consensus in strategic decision making. The approach we developed and tested in the field used a dynamic, three‐dimensional model that tracks individual programs in an organization's portfolio on their contribution to mission, money, and merit. The first dimension measures whether the organization is doing the right things; the second, whether it is doing things right financially; and the third, whether it doing things right in terms of quality. Senior managers provide their own evaluations of the organization's programs. Both the consensus view and the variation in individual assessments contribute to an improved managerial understanding of the organization's current situation and to richer discussions in strategic decision making. In field tests, this visual model proved to be a useful and powerful tool for illuminating underlying assumptions and variations in knowledge among managers facing the complex, multidimensional tradeoffs needed in strategic decision making.  相似文献   
32.
33.
34.
This study examines the relationships among personal coping resources, social support, external coping resources, job stressors and job strains in a sample of 110 American Telephone and Telegraph employees undergoing a major organizational restructuring. The study expanded on a model suggested by Ashford (1988) by defining another category of coping resources that employees may draw upon to deal with the stressors and strains which occur during major organizational changes. External coping resources were defined as those which provided employees with a sense of 'vicarious control' in stressful situations. Results indicated that personal coping resources, social support and external coping resources had a direct effect upon job stressor and strain levels. No 'buffering' effect of these coplng resources was found. Hierarchical regression analyses indicated that external coping resources added to the prediction of job stressors and strains even when pertonal coping resources and social support were entered first into the prediction questions.  相似文献   
35.
Making ends meet: perceptions of poverty in Sweden   总被引:1,自引:0,他引:1  
During the era after the Second World War, Sweden has built a welfare system based on labor market participation and income maintenance. Low unemployment and decent wages are supposed to guarantee people a labor market income or income maintenance, which in turn should provide a proper standard for everyone. However, a rapid increase in unemployment and economic problems have made the future of the Swedish welfare state more uncertain than ever. These circumstances have, among other things, led to the suggestion that Sweden should abandon the income maintenance policy and create a social policy system with the more limited ambition of guaranteeing everyone a minimum income. In that case, one central question must be answered: what constitutes a decent minimum income in today's Sweden? Where should we draw the poverty line under which people will not be forced to live? These questions are central in the current debate. The consensual poverty line method is used in this article to derive a poverty line relevant for today's Sweden. The results shows that more than every fifth household has an income below the consensual poverty line. That is, they have an income that most Swedes would argue is too low to make ends meet. The level of the consensual poverty line was compared with the National Board of Health and Welfare's guidelines for social assistance. The consensual poverty line was shown to be more generous to small households and the norm for social assistance was more generous to larger households. Finally, the expenditure for guaranteeing all Swedish household a minimum income equal to the consensual poverty line was estimated: more than SEK 25 billion per year. The results in the article casts serious doubt on the ability of the Swedish welfare state to secure a decent income to all citizens.  相似文献   
36.
37.
38.
39.
Recent studies demonstrating a concentration dependence of elimination of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) suggest that previous estimates of exposure for occupationally exposed cohorts may have underestimated actual exposure, resulting in a potential overestimate of the carcinogenic potency of TCDD in humans based on the mortality data for these cohorts. Using a database on U.S. chemical manufacturing workers potentially exposed to TCDD compiled by the National Institute for Occupational Safety and Health (NIOSH), we evaluated the impact of using a concentration- and age-dependent elimination model (CADM) (Aylward et al., 2005) on estimates of serum lipid area under the curve (AUC) for the NIOSH cohort. These data were used previously by Steenland et al. (2001) in combination with a first-order elimination model with an 8.7-year half-life to estimate cumulative serum lipid concentration (equivalent to AUC) for these workers for use in cancer dose-response assessment. Serum lipid TCDD measurements taken in 1988 for a subset of the cohort were combined with the NIOSH job exposure matrix and work histories to estimate dose rates per unit of exposure score. We evaluated the effect of choices in regression model (regression on untransformed vs. ln-transformed data and inclusion of a nonzero regression intercept) as well as the impact of choices of elimination models and parameters on estimated AUCs for the cohort. Central estimates for dose rate parameters derived from the serum-sampled subcohort were applied with the elimination models to time-specific exposure scores for the entire cohort to generate AUC estimates for all cohort members. Use of the CADM resulted in improved model fits to the serum sampling data compared to the first-order models. Dose rates varied by a factor of 50 among different combinations of elimination model, parameter sets, and regression models. Use of a CADM results in increases of up to five-fold in AUC estimates for the more highly exposed members of the cohort compared to estimates obtained using the first-order model with 8.7-year half-life. This degree of variation in the AUC estimates for this cohort would affect substantially the cancer potency estimates derived from the mortality data from this cohort. Such variability and uncertainty in the reconstructed serum lipid AUC estimates for this cohort, depending on elimination model, parameter set, and regression model, have not been described previously and are critical components in evaluating the dose-response data from the occupationally exposed populations.  相似文献   
40.
In this article, we describe a straightforward method for solving the probability of at least one malignant cell by time t, and the associated hazard function, in the general (i.e., nonhomogeneous) two-stage Moolgavkar-Venzon-Knudson (MVK) model of cancer. The method consists of solving four coupled ordinary differential equations derived from the Kolmogorov backward equations for this process. The relationship of this method to previously proposed solutions is discussed.  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