全文获取类型
收费全文 | 1788篇 |
免费 | 34篇 |
专业分类
教育 | 1438篇 |
科学研究 | 36篇 |
各国文化 | 32篇 |
体育 | 97篇 |
综合类 | 1篇 |
文化理论 | 9篇 |
信息传播 | 209篇 |
出版年
2023年 | 8篇 |
2022年 | 11篇 |
2021年 | 23篇 |
2020年 | 30篇 |
2019年 | 59篇 |
2018年 | 85篇 |
2017年 | 87篇 |
2016年 | 67篇 |
2015年 | 40篇 |
2014年 | 68篇 |
2013年 | 447篇 |
2012年 | 48篇 |
2011年 | 45篇 |
2010年 | 56篇 |
2009年 | 53篇 |
2008年 | 55篇 |
2007年 | 46篇 |
2006年 | 29篇 |
2005年 | 40篇 |
2004年 | 45篇 |
2003年 | 29篇 |
2002年 | 26篇 |
2001年 | 25篇 |
2000年 | 24篇 |
1999年 | 20篇 |
1998年 | 10篇 |
1997年 | 22篇 |
1996年 | 18篇 |
1995年 | 22篇 |
1994年 | 22篇 |
1993年 | 19篇 |
1992年 | 10篇 |
1991年 | 20篇 |
1990年 | 16篇 |
1989年 | 10篇 |
1988年 | 9篇 |
1986年 | 12篇 |
1985年 | 9篇 |
1984年 | 22篇 |
1983年 | 11篇 |
1982年 | 14篇 |
1981年 | 12篇 |
1980年 | 14篇 |
1979年 | 9篇 |
1978年 | 6篇 |
1977年 | 10篇 |
1976年 | 10篇 |
1975年 | 8篇 |
1974年 | 13篇 |
1973年 | 7篇 |
排序方式: 共有1822条查询结果,搜索用时 15 毫秒
91.
The authors investigated whether some advantages of tutoring over other instructional methods are due to microadaptation, or, tutors basing their actions on assessments of tutees they develop during tutoring. In a 2 × 2 between-subjects experiment, independent variables were shared experience (tutors either worked with the same or a different tutee in each of four segment of the tutoring session) and communication context (face-to-face or computer-mediated). Although there were no overall learning differences across experience conditions, tutees who worked with the same tutor demonstrated better learning of concepts initially discussed during the final tutoring segment. Shared experience led to accurate competence assessments only in the computer-mediated context, suggesting that cognitive load influences assessment development. However, there was no evidence of micro-adaptation. 相似文献
92.
93.
94.
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
95.
Alexander H. Montoye Karin A. Pfeiffer Darijan Suton Stewart G. Trost 《Measurement in physical education and exercise science》2014,18(4):273-285
The responsiveness to change of the Actical and ActiGraph accelerometers was assessed in children and adolescents. Participants (N = 208) aged 6 to 16 years completed two simulated free-living protocols, one with primarily light-to-moderate physical activity (PA) and one with mostly moderate-to-vigorous PA. Time in sedentary, light, moderate, and vigorous PA was estimated using 8 previously developed cut-points (4 for Actical and 4 for ActiGraph) and 5-sec, 15-sec, and 30-sec epochs. Accelerometer responsiveness for detecting differences in PA between protocols was assessed using standardized response means (SRMs). SRM values ≥.8 represented high responsiveness to change. Both accelerometers showed high responsiveness for all PA intensities (SRMs = 1.2–4.7 for Actical and 1.1–3.3 for ActiGraph). All cut-points and epoch lengths yielded high responsiveness, and choice of cut-points and epoch length had little effect on responsiveness. Thus, both the Actical and ActiGraph can detect change in PA in a simulated free-living setting, irrespective of cut-point selection or epoch length. 相似文献
96.
97.
Karin Scager Sanne F. Akkerman Albert Pilot Theo Wubbels 《Teaching in Higher Education》2017,22(3):318-335
Students need to be challenged to stimulate their learning. Applying challenge in practice however is not straightforward. Challenging students may conflict with other teacher responsibilities, creating potential dilemmas for teachers. This study discloses dilemmas teachers encounter when challenging students as well as the considerations accompanying their actual choices for action when coping with these dilemmas. Based on interviews with teachers, first, a dilemma analysis instrument was developed. Seven main categories of dilemmas were found. One of the main dilemmas encompassed maximizing challenge versus keeping all students on board. University students differ in their ability, confronting teachers with the feeling that choosing to serve one group could be detrimental to the learning of others. The diversity of choices and considerations brought forward by the teachers indicates that it matters who the teacher is, and what he or she stands for and is able to do. 相似文献
98.
Education and Information Technologies - 3D printing is an emerging educational technology that is said to prepare learners for a more technologically designed world. In this review, 3D printing... 相似文献
99.
Ann Bailey James Funk David Lessley Chris Sherwood Jeff Crandall William Neale 《Sports biomechanics / International Society of Biomechanics in Sports》2020,19(5):678-700
ABSTRACT Professional American football games are recorded in digital video with multiple cameras, often at high resolution and high frame rates. The purpose of this study was to evaluate the accuracy of a videogrammetry technique to calculate translational and rotational helmet velocity before, during and after a helmet impact. In total, 10 football impacts were staged in a National Football League (NFL) stadium by propelling helmeted 50th percentile male crash test dummies into each other or the ground at speeds and orientations representative of concussive impacts for NFL players. The tests were recorded by experienced sports film crews to obtain video coverage and quality typically available for NFL games. A videogrammetry procedure was used to track the position and rotation of the helmet throughout the relevant time interval of the head impact. Compared with rigidly mounted retroreflective marker three dimensional (3-D) motion tracking that was concurrently collected in the experiments, videogrammetry accurately calculated changes in translational and rotational velocity of the helmet using high frame rate (two cameras at 240 Hz) video (7% and 15% error, respectively). Low frame rate (2 cameras at 60 Hz) video was adequate for calculating pre-impact translational velocity but not for calculating the translational or rotational velocity change of the helmet during impact. 相似文献
100.