全文获取类型
收费全文 | 28067篇 |
免费 | 676篇 |
国内免费 | 162篇 |
专业分类
管理学 | 2389篇 |
劳动科学 | 61篇 |
民族学 | 678篇 |
人才学 | 15篇 |
人口学 | 2693篇 |
丛书文集 | 5264篇 |
理论方法论 | 1434篇 |
综合类 | 8257篇 |
社会学 | 5465篇 |
统计学 | 2649篇 |
出版年
2024年 | 8篇 |
2023年 | 85篇 |
2022年 | 238篇 |
2021年 | 231篇 |
2020年 | 215篇 |
2019年 | 194篇 |
2018年 | 1863篇 |
2017年 | 2018篇 |
2016年 | 1326篇 |
2015年 | 592篇 |
2014年 | 718篇 |
2013年 | 1029篇 |
2012年 | 1233篇 |
2011年 | 2446篇 |
2010年 | 2393篇 |
2009年 | 2227篇 |
2008年 | 2064篇 |
2007年 | 2512篇 |
2006年 | 1540篇 |
2005年 | 1444篇 |
2004年 | 898篇 |
2003年 | 725篇 |
2002年 | 632篇 |
2001年 | 477篇 |
2000年 | 339篇 |
1999年 | 289篇 |
1998年 | 159篇 |
1997年 | 173篇 |
1996年 | 202篇 |
1995年 | 127篇 |
1994年 | 105篇 |
1993年 | 86篇 |
1992年 | 84篇 |
1991年 | 55篇 |
1990年 | 39篇 |
1989年 | 30篇 |
1988年 | 45篇 |
1987年 | 22篇 |
1986年 | 8篇 |
1985年 | 12篇 |
1984年 | 7篇 |
1983年 | 4篇 |
1982年 | 1篇 |
1981年 | 5篇 |
1980年 | 5篇 |
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
11.
随着勘探程度的深入,为了扩大四川盆地天然气勘探领域、寻找新的勘探接替区,四川盆地的勘探区域由盆内逐渐向盆缘延伸。在这种背景下,川东北地区须家河组二段相继取得新的勘探成果,但在勘探开发过程中逐渐暴露了诸如区块之间气井产能差异大,储层的碎屑组分、结构及厚度、物性、孔隙结构差异明显等问题,制约了勘探开发的步伐。针对上述问题,根据岩芯观察描述、分析化验资料及测井解释成果,从沉积、成岩方面入手,对比剖析了川东北龙岗和营山地区须二段储层特征的差异性及其成因,认为远离物源区和高能水体的反复淘洗是造成储层差异性的首要因素,强烈的压实作用和多期石英加大对储层差异性起关键作用,自生绿泥石衬边胶结和长石选择性溶蚀最终决定了储层差异性。从而解释了气藏勘探开发中遇到的诸多问题,对有效指导该区的下一步勘探开发工作具有重要意义。 相似文献
12.
20世纪80年代以来,随着中国城市发展速度的持续提升,各级各类城市机场的建设步伐也不断加快,时至今日,机场已经成为了许多城市重要的对外交通枢纽和新的城市商业中心。但以噪声污染为重要表征的负外部性输出,在中国城市机场也呈现出蔓延之势。文章通过相关文献资料梳理发现,国外对城市机场噪声的治理一般通过机场规划、降噪技术、噪声征税、制度规制、强化绿化等多种路径展开。了解国外治理城市机场噪声的实践探索,对于我们寻求中国城市机场噪声治理的未来道路,具有重要的启示和借鉴意义。 相似文献
13.
14.
Moritz Geisreiter 《Organisationsberatung, Supervision, Coaching》2018,25(2):229-238
The longstanding focus of elite athletes on top sports entails disadvantages hampering their later entry to the world of work. In order to successfully contribute their outstanding personality traits to a later job, athletes are thus particularly required to care for their employability. Contributing to this, the author carried out a competency balancing with top athletes. This coaching method significantly decreased the athletes’ need for self-information. Evaluation further showed indications of increased clarity and certainty of occupational goals as well as work satisfaction. 相似文献
15.
There is considerable speculation that female political empowerment could improve population health. Yet, evidence to date is limited, and explanations for why political empowerment would matter and the conditions under which this might be enhanced or muted are not well understood. In this article, we draw on theoretical work on the politics of representation to frame an investigation of whether increases in the percentage of females in a country’s parliament influence mortality rates. We further examine whether the relationship is conditioned by extent of democracy and economic and social development. Through multivariate longitudinal regression, we analyze four indicators of mortality in 155 countries spanning 1990 to 2014 with controls for initial country conditions, time-stable structural predispositions to higher mortality, and a number of time-varying potential confounders. Results indicate that a high level of female representation—30 % or greater in our models—has large negative associations with mortality, that these are particularly strong in lesser developed and weak democratic contexts, that high female political representation effectively offsets liabilities associated with low development, and that the relationships are robust to various operationalizations of social development. In the end, our research provides a particularly thorough accounting of the relationship between female political representation and population health, particularly by specifying the conditions under which female representation is most salient. In doing so, the research suggests important links between issues of female empowerment, political context, and developmental trajectories of countries more generally. 相似文献
16.
Bioequivalence (BE) studies are designed to show that two formulations of one drug are equivalent and they play an important role in drug development. When in a design stage, it is possible that there is a high degree of uncertainty on variability of the formulations and the actual performance of the test versus reference formulation. Therefore, an interim look may be desirable to stop the study if there is no chance of claiming BE at the end (futility), or claim BE if evidence is sufficient (efficacy), or adjust the sample size. Sequential design approaches specially for BE studies have been proposed previously in publications. We applied modification to the existing methods focusing on simplified multiplicity adjustment and futility stopping. We name our method modified sequential design for BE studies (MSDBE). Simulation results demonstrate comparable performance between MSDBE and the original published methods while MSDBE offers more transparency and better applicability. The R package MSDBE is available at https://sites.google.com/site/modsdbe/ . Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
17.
This paper develops a unified model of dual and unitary job holding based on a Stone-Geary utility function. The model incorporates both constrained and unconstrained labor supply. Panel data methods are adapted to accommodate unobserved heterogeneity and multinomial selection into six mutually exclusive labor supply regimes. We estimate the wage and income elasticities arising from selection and unobserved heterogeneity as well as from the Stone-Geary Slutsky equations. The labor supply model is estimated with data from the British Household Panel Survey 1991–2008. Among dual job holders, our study finds that the Stone-Geary income and wage elasticities are much larger for labor supply to the second job compared with the main job. When the effects of selection and unobserved heterogeneity are taken account of, the magnitudes of these elasticities on the second job tend to be significantly reduced. 相似文献
18.
Economic theory establishes that pension privatization weakens the link between old and young and so reduces the incentive to invest in public education in an economy with lower return rate of capital than growth rate of wage. However, empirical studies of the link change are few. In this paper, we investigate the effects of pension privatization and the central government’s subsidy to individual accounts on public education spending in a three-period overlapping generation model. And then, we take contemporary pension reforms in a number of Chinese provinces as offering natural experiment conditions. Using a difference-in-difference framework and 282 municipal districts panel data over years 1998–2009, we test the pension-education theoretical link change. Both our theoretical and empirical results confirm that pension privatization is adversely associated with local public spending on education in China. Private pension subsidies, moreover, magnify this effect. Our study supports the theoretical assertion and selective empirical findings of a negative intergenerational effect of pension privatization. 相似文献
19.
王传兴 《同济大学学报(社会科学版)》2003,14(2):15-19
冷战结束十年以来 ,美国的对华政策依然摇摆不定。之所以如此 ,是因为十年来美国视中国为敌还是为友 ,或者非敌非友 ,至今还未定性。而美国难于在其国际政治安全战略中给中国定性的原因 ,则与以下的三个层次密切相关 ,即美国的国内政治层次、中美关系的发展层次和全球层次。 相似文献
20.
金诗学唐的历程 总被引:1,自引:0,他引:1
王锡九 《南京工业大学学报(社会科学版)》2003,2(2):49-54
金代诗歌在受苏轼等宋代诗人的影响之外 ,也受到唐诗的浸润。本文依据金诗发展变化的自身情况 ,考察了金诗学唐的历程。文中将金诗学唐分为金初“借才异代”时期、“国朝文派”时期、金代后期等三个阶段 ,做了比较详细的论述 ,从一个方面展示了金诗发展的轨迹 ,揭示了金诗的某些重要特点 ,对于我们深入地认识金诗是有裨益的 相似文献