全文获取类型
收费全文 | 1078篇 |
免费 | 20篇 |
国内免费 | 3篇 |
专业分类
教育 | 731篇 |
科学研究 | 78篇 |
各国文化 | 17篇 |
体育 | 118篇 |
文化理论 | 22篇 |
信息传播 | 135篇 |
出版年
2023年 | 4篇 |
2022年 | 15篇 |
2021年 | 18篇 |
2020年 | 21篇 |
2019年 | 35篇 |
2018年 | 49篇 |
2017年 | 47篇 |
2016年 | 49篇 |
2015年 | 32篇 |
2014年 | 40篇 |
2013年 | 201篇 |
2012年 | 36篇 |
2011年 | 37篇 |
2010年 | 39篇 |
2009年 | 34篇 |
2008年 | 32篇 |
2007年 | 49篇 |
2006年 | 32篇 |
2005年 | 31篇 |
2004年 | 30篇 |
2003年 | 32篇 |
2002年 | 21篇 |
2001年 | 21篇 |
2000年 | 9篇 |
1999年 | 10篇 |
1998年 | 14篇 |
1997年 | 6篇 |
1996年 | 10篇 |
1995年 | 6篇 |
1994年 | 8篇 |
1993年 | 5篇 |
1991年 | 7篇 |
1989年 | 6篇 |
1988年 | 4篇 |
1987年 | 11篇 |
1986年 | 4篇 |
1985年 | 8篇 |
1984年 | 5篇 |
1983年 | 6篇 |
1982年 | 5篇 |
1981年 | 4篇 |
1977年 | 4篇 |
1976年 | 6篇 |
1975年 | 5篇 |
1973年 | 6篇 |
1972年 | 4篇 |
1971年 | 4篇 |
1970年 | 4篇 |
1968年 | 3篇 |
1966年 | 3篇 |
排序方式: 共有1101条查询结果,搜索用时 15 毫秒
51.
Selznick Benjamin S. Mayhew Matthew J. Zhang Lini McChesney Eric T. 《Research in higher education》2022,63(4):567-588
Research in Higher Education - This study examines how collegiate climates and practices can promote innovation capacities among an international longitudinal sample of undergraduate women. Using a... 相似文献
52.
53.
Catalina Rey-Guerra Henrik D. Zachrisson Eric Dearing Daniel Berry Susanne Kuger Margaret R. Burchinal Ane Nærde Thomas van Huizen Sylvana M. Côté 《Child development》2023,94(2):458-477
Whether high quantities of center-based care cause behavior problems is a controversial question. Studies using covariate adjustment for selection factors have detected relations between center care and behavior problems, but studies with stronger internal validity less often find such evidence. We examined whether within-child changes in hours in center-based care predicted changes in externalizing problems in toddlers and preschoolers (N = 10,105; 49% female; data collection 1993–2012) in seven studies, including from Germany, Netherlands, Norway, two from Canada and two from the U.S. Race/ethnicity data were only collected in the United States (57% and 80% White; 42% and 13% African-American; 1.2% and 5% Latinx). Meta-analyses showed no association (r = .00, p = .88) between hours in center-based care and externalizing problems. 相似文献
54.
In this paper we report upon a first empirical exploration of the relative efficiency of innovation development by product users vs. product producers. In a study of over 50 years of product innovation in the whitewater kayaking field, we find users in aggregate were approximately 3× more efficient at developing important kayaking product innovations than were producers in aggregate. We speculate that this result is driven by what we term “efficiencies of scope” in problem-solving. These can favor an aggregation of many user innovators, each spending a little, over fewer producer innovators benefitting from higher economies of scale in product development. We also note that the present study explores only one initial point on what is likely to be a complex efficiency landscape. 相似文献
55.
Gunn B.B. Kristensen Kristin Moberg Aakre Ann Helen Kristoffersen Sverre Sandberg 《Biochemia medica : ?asopis Hrvatskoga dru?tva medicinskih biokemi?ara / HDMB》2014,24(1):114-122
In laboratory medicine, several studies have described the most frequent errors in the different phases of the total testing process, and a large proportion of these errors occur in the pre-analytical phase. Schemes for registration of errors and subsequent feedback to the participants have been conducted for decades concerning the analytical phase by External Quality Assessment (EQA) organizations operating in most countries. The aim of the paper is to present an overview of different types of EQA schemes for the pre-analytical phase, and give examples of some existing schemes. So far, very few EQA organizations have focused on the pre-analytical phase, and most EQA organizations do not offer pre-analytical EQA schemes (EQAS). It is more difficult to perform and standardize pre-analytical EQAS and also, accreditation bodies do not ask the laboratories for results from such schemes. However, some ongoing EQA programs for the pre-analytical phase do exist, and some examples are given in this paper. The methods used can be divided into three different types; collecting information about pre-analytical laboratory procedures, circulating real samples to collect information about interferences that might affect the measurement procedure, or register actual laboratory errors and relate these to quality indicators. These three types have different focus and different challenges regarding implementation, and a combination of the three is probably necessary to be able to detect and monitor the wide range of errors occurring in the pre-analytical phase. 相似文献
56.
57.
58.
Eric Sprigings Peter McNair Grant Mawston David Sumner Mark Boocock 《Sports Engineering》2006,9(3):147-153
The intent of this project was to explore the feasibility of personalising the paddle blade size for individual flatwater
kayakers based on their power output profiles. Twelve elite male kayakers performed on a kayak ergometer at the same intensity
and resistance that they would normally experience while paddling at race pace for 500 m on the water. The kayak ergometer
was instrumented so that power profiles could be determined from the instantaneous force and velocity of the representative
centre point of the paddle blade. From the power profile information, the researchers calculated a personalised blade size
that was expected to improve performance for those kayakers differing more than 5% from the calculated ‘ideal’ size. For the
elite kayakers studied, it was recommended that seven of the paddlers should increase their blade size by approximately 5–10%.
For the remaining five paddlers, the results indicated that their current blade sizes were within the expected measurement
error of their predicted ideal value and should be retained. It is anticipated that this research will provide the theoretical
rationale for elite kayakers to see the need to personalise their blade size based on their own muscle power profiles. 相似文献
59.
This paper is a commentary on the classroom interventions on the teaching and learning of proof reported in the seven empirical papers in this special issue. The seven papers show potential to enhance student learning in an area of mathematics that is not only notoriously difficult for students to learn and for teachers to teach, but also critically important to knowing and doing mathematics. Although the seven papers, and the intervention studies they report, vary in many ways—student population, content domain, goals and duration of the intervention, and theoretical perspectives, to name a few—they all provide valuable insight into ways in which classroom experiences might be designed to positively influence students’ learning to prove. In our commentary, we highlight the contributions and promise of the interventions in terms of whether and how they present capacity to change the classroom culture, the curriculum, or instruction. In doing so, we distinguish between works that aim to enhance students’ preparedness for, and competence in, proof and proving and works that explicitly foster appreciation for the need and importance of proof and proving. Finally, we also discuss briefly the interventions along three dimensions: how amenable to scaling up, how practicable for curricular integration, and how capable of producing long-lasting effects these interventions are. 相似文献
60.