全文获取类型
收费全文 | 15413篇 |
免费 | 390篇 |
专业分类
管理学 | 2148篇 |
民族学 | 74篇 |
人才学 | 5篇 |
人口学 | 1272篇 |
丛书文集 | 93篇 |
教育普及 | 2篇 |
理论方法论 | 1485篇 |
综合类 | 359篇 |
社会学 | 7721篇 |
统计学 | 2644篇 |
出版年
2023年 | 81篇 |
2021年 | 81篇 |
2020年 | 240篇 |
2019年 | 308篇 |
2018年 | 314篇 |
2017年 | 454篇 |
2016年 | 368篇 |
2015年 | 298篇 |
2014年 | 332篇 |
2013年 | 2482篇 |
2012年 | 496篇 |
2011年 | 401篇 |
2010年 | 294篇 |
2009年 | 317篇 |
2008年 | 364篇 |
2007年 | 360篇 |
2006年 | 314篇 |
2005年 | 457篇 |
2004年 | 369篇 |
2003年 | 339篇 |
2002年 | 351篇 |
2001年 | 378篇 |
2000年 | 338篇 |
1999年 | 367篇 |
1998年 | 256篇 |
1997年 | 235篇 |
1996年 | 245篇 |
1995年 | 211篇 |
1994年 | 246篇 |
1993年 | 218篇 |
1992年 | 268篇 |
1991年 | 266篇 |
1990年 | 246篇 |
1989年 | 245篇 |
1988年 | 225篇 |
1987年 | 215篇 |
1986年 | 212篇 |
1985年 | 215篇 |
1984年 | 241篇 |
1983年 | 227篇 |
1982年 | 192篇 |
1981年 | 155篇 |
1980年 | 151篇 |
1979年 | 178篇 |
1978年 | 152篇 |
1977年 | 132篇 |
1976年 | 117篇 |
1975年 | 112篇 |
1974年 | 111篇 |
1973年 | 102篇 |
排序方式: 共有10000条查询结果,搜索用时 546 毫秒
31.
Abstract The effect of nonfarm development on dairy farm survival in New York's highly developed lower Hudson Valley is analyzed. The major hypothesis is that significant losses of dairy farms during this period are the result of urban development pressures. Contrary to this hypothesis, however, the bivariate and multivariate analyses of data from a mail survey of all commercial dairy operators in Dutchess County as of 1984 and industry survivors, exiters, and new entrants through 1990 demonstrate that nonfarm development has a negligible effect on dairy farm survival; rather, survival is significantly affected by age of operator and by family disruption. Thus, demographic and family process factors are found to be more powerful determinants of dairy farm survival in this particular metropolitan context. 相似文献
32.
对林业税费的经济学分析 总被引:3,自引:0,他引:3
田明华 《北京林业大学学报(社会科学版)》2002,(Z1)
该文运用经济学的基本工具———供给和需求曲线 ,以商品林为研究对象 ,探讨了林业税费的作用机理和内涵。该文认为商品林生产具有正的外部性 ,市场失灵使生产者将不能提供社会真正所需要的商品林数量。在封闭的市场条件下 ,林业税费会直接成为价格的一部分 ,商品林生产者应当能够获得正常利润 ,与税费高低无关 ,但会使一部分林地退出生产。林业补贴是一种负的林业税收。在开放市场经济条件下 ,国内商品林供应量低于没有林业税收时的商品林供应量 ,更低于考虑社会生态需求时的商品林供应量 ,造成巨大的社会福利损失 ,应减免林业税费、增加林业扶持、取消价格管制。该文进一步研究了与林业税费密切相关的森林采伐限额政策 ,认为对商品林应该完全取消采伐限额政策 相似文献
33.
教学管理是教学工作运转的支柱,教学管理的优劣影响着教学质量。该文介绍了外语学院教学管理工作的基本内容,包括教学任务的布置落实、教学检查、教学文件的建设、学籍管理,以及结合学院的实际情况完善考试制度、制定成绩管理细则和考试结果奖励办法等。 相似文献
34.
Paul Atkinson 《The Sociological review》2005,53(2):380-382
35.
36.
Medical fraud and overservicing are estimated to cost the Australian community between $130 and $200 million per annum, a figure far greater than the national cost of burglary and almost the same as the total property loss from all conventional crime. An examination of the social antecedents of medical fraud and overservicing suggests that the predisposition of some doctors to engage in these practices occurs because of the following: (1) medical training and professional socialization that orientate student doctors away from altruistic health issues towards narrower self-interested professional concerns; (2) career expectations of a high pattern of material consumption that are often frustrated by an increasingly competitive medical market place; and (3) professional medical organizations that lobby for national health policies which reflect the mercenary self-interest of doctors rather than the health interest of the nation. 相似文献
37.
The Analysis of Verbal Behavior - 相似文献
38.
Amy H. Herring Joseph G. Ibrahim Stuart R. Lipsitz 《Journal of the Royal Statistical Society. Series C, Applied statistics》2004,53(2):293-310
Summary. Non-ignorable missing data, a serious problem in both clinical trials and observational studies, can lead to biased inferences. Quality-of-life measures have become increasingly popular in clinical trials. However, these measures are often incompletely observed, and investigators may suspect that missing quality-of-life data are likely to be non-ignorable. Although several recent references have addressed missing covariates in survival analysis, they all required the assumption that missingness is at random or that all covariates are discrete. We present a method for estimating the parameters in the Cox proportional hazards model when missing covariates may be non-ignorable and continuous or discrete. Our method is useful in reducing the bias and improving efficiency in the presence of missing data. The methodology clearly specifies assumptions about the missing data mechanism and, through sensitivity analysis, helps investigators to understand the potential effect of missing data on study results. 相似文献
39.
For a wide variety of applications, experiments are based on units ordered over time or space. Models for these experiments generally may include one or more of: correlations, systematic trends, carryover effects and interference effects. Since the standard optimal block designs may not be efficient in these situations, orthogonal arrays of type I and type II, which were introduced in 1961 by C.R. Rao [Combinatorial arrangements analogous to orthogonal arrays, Sankhya A 23 (1961) 283–286], have been recently used to construct optimal and efficient designs for many of these experiments. Results in this area are unified and the salient features are outlined. 相似文献
40.