全文获取类型
收费全文 | 187703篇 |
免费 | 4981篇 |
国内免费 | 1933篇 |
专业分类
管理学 | 4078篇 |
劳动科学 | 36篇 |
民族学 | 3097篇 |
人才学 | 27篇 |
人口学 | 2507篇 |
丛书文集 | 25169篇 |
理论方法论 | 7821篇 |
综合类 | 136722篇 |
社会学 | 6858篇 |
统计学 | 8302篇 |
出版年
2024年 | 303篇 |
2023年 | 939篇 |
2022年 | 1307篇 |
2021年 | 1578篇 |
2020年 | 2024篇 |
2019年 | 1976篇 |
2018年 | 1978篇 |
2017年 | 2532篇 |
2016年 | 2672篇 |
2015年 | 3644篇 |
2014年 | 8913篇 |
2013年 | 11286篇 |
2012年 | 11218篇 |
2011年 | 13209篇 |
2010年 | 10766篇 |
2009年 | 11096篇 |
2008年 | 11707篇 |
2007年 | 14636篇 |
2006年 | 14651篇 |
2005年 | 13592篇 |
2004年 | 12729篇 |
2003年 | 12441篇 |
2002年 | 10067篇 |
2001年 | 8485篇 |
2000年 | 4777篇 |
1999年 | 1407篇 |
1998年 | 762篇 |
1997年 | 617篇 |
1996年 | 534篇 |
1995年 | 451篇 |
1994年 | 336篇 |
1993年 | 304篇 |
1992年 | 254篇 |
1991年 | 202篇 |
1990年 | 118篇 |
1989年 | 153篇 |
1988年 | 88篇 |
1987年 | 60篇 |
1986年 | 49篇 |
1985年 | 113篇 |
1984年 | 156篇 |
1983年 | 103篇 |
1982年 | 100篇 |
1981年 | 66篇 |
1980年 | 60篇 |
1979年 | 58篇 |
1978年 | 55篇 |
1977年 | 20篇 |
1976年 | 14篇 |
1975年 | 9篇 |
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
131.
董仲其 《四川大学学报(哲学社会科学版)》2004,27(5):44-48
恩格斯晚年曾对《共产党宣言》何以这样冠名有一个追忆性的说明 ;在另一地方他又明确讲到“三十年不曾使用”共产主义一词的事。这两段话虽然是在不同时间、地点、情况下说的 ,却有着密切的联系 ,后一段话恰恰是解答为什么会有前段话的说明的根据 相似文献
132.
刘瑶 《山西大学学报(哲学社会科学版)》2003,26(1):123-126
第十四届釜山亚运会 ,中国代表团以绝对优势 ,位于亚洲各国之首 ,但是与世界体育强国相比较 ,还有一定的差距。本文通过对釜山亚运会的反思 ,具体分析我国的优势项目与不足之处 ,在今后的 6年中 ,全面改进 ,才能使中国军团在北京奥运会再创佳绩。 相似文献
133.
Summary Based on 14 case studies of highly effective therapies and the reasons they succeeded less frequently than they could, we
propose a variety of steps to improve the health care system of the U.S.A. Whatever proposal emerges from current national
debates until innovations are shown to be safe and effective, they should not be supported; when slightly better technologies
are much more expensive than other good ones we need to consider appropriate choices carefully; simplified billing and bookkeping
would reduce our costs; when a technology is rapidly introduced cautionnary measures may be needed; tracking immunization
and repairing their omissions requires a new system; educational programs such as seen effective in hypertension should be
applied in other areas such as vaccination; in organ transplantation the nation should consider “presumed consent”; our payment
system sometimes creates perverse incentives and therefore needs review; and the preferences of the public in allocation of
health resources need to be discovered once the public is informed about the issues.
Research supported by Andrew W. Mellon Foundation. 相似文献
134.
喻典 《湖北师范学院学报(哲学社会科学版)》1992,(6)
本文研究了原子价层轨道能与共价型分子氢化物中A-H键的振动频率v_(A-H)的关系,结果表明二者间有良好的线性关系,其计算式为: v_(A-H)=-a∑n_1E_1/∑n_1(A)+b (1) V_(A-H)=-c∑n_1E_1/∑n~(B)+d (2)利用上式计算的振动频率V_(A-H)值接近于文献值。从而验证了用韩长日方法计算电负性的合理性。 相似文献
135.
Lee Friedman Edwin A. Fleishman Jennifer Mikulka Fletcher 《Journal of Engineering and Technology Management》1992,9(3-4)
This study attempted to identify the primary activities performed by R&D managers at different supervisory levels, and the cognitive and interpersonal ability requirements that underlie these activities. A task inventory containing 244 managerial tasks was completed by 117 R&D managers in nine organizations. The 48 tasks which managers rated as having spent the most time were factor analyzed, resulting in the identification of three primary activities: project management, personnel supervision, and strategic planning. Furthermore, these activities varied with supervisory level, with R&D managers performing a wider range of these activities with the progression from first-line to upper-level management.Thirty R&D managers later rated the degree to which 19 cognitive and interpersonal abilities were required for performing these primary activities. Strategic planning was rated as requiring significantly higher levels of oral expression, logical reasoning, originality, fluency of ideas, oral defense, and resistance to premature judgement than was required for the other two primary activities. Personnel supervision required a higher level of social sensitivity than was required for the other two activities. Project management required high levels of information ordering, oral fact- finding ability, problem sensitivity, and oral and written comprehension. Implications of the findings for understanding R&D managerial performance and personnel staffing functions are discussed. 相似文献
136.
陈维昭 《汕头大学学报(人文社会科学版)》1996,(1)
《红楼梦》自诞生以来,被当成各种属性的文本,它在不同的学科领域被接受,而对于任何一个学科来说,《红楼梦》的阅读现象都呈现出一种边界性。这根源于文本《红楼梦》的边界性,它本身具有小说学、经学、朴学的因素。这种边界性正是红学的生机之所在。边界性不等于混乱与无充,从方法论看,红学具有两个世界;事实还原的世界和意义诠释的世界。 相似文献
137.
沈木珠 《深圳大学学报(人文社会科学版)》1992,(1)
1989年通过的国际救助公约对传统的“无效果无报酬”原则所作的例外规定,引起了海运界和贸易界的极大关注,从而导致某些国际规则和国内法的修订。本文运用比较的方法对海上救助公约的发展及其对英国劳氏标准救助契约、国际共同海损理算规则和我国海商法的影响作了论述,并且提出了我国当前海商法应作修改补充的几点建议。 相似文献
138.
发展了Baksalary和Drygas提出的一般Gauss-Markov模型中线性充分性、最小充分性和完全性的概念,用Rao的最小二乘统一理论,给出了这些概念的刻划定理。 相似文献
139.
刘军 《华北水利水电学院学报(社会科学版)》2002,18(1):55-58
文化与河流的关系十分特殊,文化既源于河流,又反过来改造河流。文章重点阐述了文化如何由源于河流到改造河流,如何由被动地改造河流到主动地改造河流的过程。 相似文献
140.
Charles W. Griffiths Chris Dockins Nicole Owens Nathalie B. Simon Daniel A. Axelrad 《Risk analysis》2002,22(4):679-688
To quantify the health benefits of environmental policies, economists generally require estimates of the reduced probability of illness or death. For policies that reduce exposure to carcinogenic substances, these estimates traditionally have been obtained through the linear extrapolation of experimental dose-response data to low-exposure scenarios as described in the U.S. Environmental Protection Agency's Guidelines for Carcinogen Risk Assessment (1986). In response to evolving scientific knowledge, EPA proposed revisions to the guidelines in 1996. Under the proposed revisions, dose-response relationships would not be estimated for carcinogens thought to exhibit nonlinear modes of action. Such a change in cancer-risk assessment methods and outputs will likely have serious consequences for how benefit-cost analyses of policies aimed at reducing cancer risks are conducted. Any tendency for reduced quantification of effects in environmental risk assessments, such as those contemplated in the revisions to EPA's cancer-risk assessment guidelines, impedes the ability of economic analysts to respond to increasing calls for benefit-cost analysis. This article examines the implications for benefit-cost analysis of carcinogenic exposures of the proposed changes to the 1986 Guidelines and proposes an approach for bounding dose-response relationships when no biologically based models are available. In spite of the more limited quantitative information provided in a carcinogen risk assessment under the proposed revisions to the guidelines, we argue that reasonable bounds on dose-response relationships can be estimated for low-level exposures to nonlinear carcinogens. This approach yields estimates of reduced illness for use in a benefit-cost analysis while incorporating evidence of nonlinearities in the dose-response relationship. As an illustration, the bounding approach is applied to the case of chloroform exposure. 相似文献