全文获取类型
收费全文 | 3131篇 |
免费 | 68篇 |
国内免费 | 2篇 |
专业分类
教育 | 2534篇 |
科学研究 | 108篇 |
各国文化 | 41篇 |
体育 | 117篇 |
文化理论 | 17篇 |
信息传播 | 384篇 |
出版年
2022年 | 15篇 |
2021年 | 31篇 |
2020年 | 50篇 |
2019年 | 80篇 |
2018年 | 98篇 |
2017年 | 121篇 |
2016年 | 90篇 |
2015年 | 74篇 |
2014年 | 77篇 |
2013年 | 800篇 |
2012年 | 77篇 |
2011年 | 98篇 |
2010年 | 79篇 |
2009年 | 81篇 |
2008年 | 84篇 |
2007年 | 87篇 |
2006年 | 78篇 |
2005年 | 68篇 |
2004年 | 73篇 |
2003年 | 57篇 |
2002年 | 65篇 |
2001年 | 53篇 |
2000年 | 54篇 |
1999年 | 39篇 |
1998年 | 37篇 |
1997年 | 57篇 |
1996年 | 36篇 |
1995年 | 36篇 |
1994年 | 35篇 |
1993年 | 35篇 |
1992年 | 34篇 |
1991年 | 31篇 |
1990年 | 27篇 |
1989年 | 27篇 |
1988年 | 26篇 |
1987年 | 12篇 |
1986年 | 29篇 |
1985年 | 28篇 |
1984年 | 25篇 |
1983年 | 26篇 |
1982年 | 23篇 |
1981年 | 16篇 |
1980年 | 29篇 |
1979年 | 23篇 |
1978年 | 24篇 |
1977年 | 21篇 |
1976年 | 18篇 |
1975年 | 11篇 |
1973年 | 14篇 |
1969年 | 11篇 |
排序方式: 共有3201条查询结果,搜索用时 267 毫秒
161.
The purpose of this study was to investigate the effect of impaired reading skills and visual discomfort on the reading rate and comprehension of university students when reading texts presented at a high school (Grade 9) or university (Grade 12) level of difficulty. Groups included impaired readers (n=18) and normal readers with (n=13) or without visual discomfort (n=19). Regardless of text difficulty the impaired reader group had a significantly slower reading rate and poorer comprehension than the normal reader control group. However, when reading rate and comprehension were compared at the assessed reading level of each group, no group differences were found. The normal reading visual discomfort group had poorer reading comprehension than other normal readers with presentation of university‐level text only. It was concluded that poor word decoding skills may exacerbate comprehension difficulties in impaired readers. In contrast, the comprehension difficulties found for normal readers with visual discomfort occurred because of the somatic and perceptual difficulties induced with exposure to the repetitive striped patterns found on text pages. The types of strategy needed to increase the reading efficiency and produce greater academic success in university students with impaired reader skills or visual discomfort are discussed. 相似文献
162.
This article describes an interactive activity that involves students participating in a memory recall test. Data collected from the activity may be used to illustrate the one‐sample t test or one‐sample sign test. 相似文献
163.
The current investigation was designed to identify emotion states students experience during mathematics activities, and in particular to distinguish emotions contingent on experiences of success and experiences of failure. Students’ task-related emotional responses were recorded following experiences of success and failure while working with an individualised computer-based mathematics learning environment. In addition, relations between these patterns of emotional responses after success and failure experiences and trait-like motivational variables, self-concept of ability, subject value, orientation to learning from errors, goal orientation and causal attributions, were examined. Two separate studies are reported. In Study 1 emotions associated with success and failure experiences in mathematics were investigated in relation to self-concept of ability, subject value and orientation to learning from errors. In Study 2, patterns of emotion following success and failure were examined in relation to students’ goal orientation and their causal attributions for success in school. 相似文献
164.
Teachers are encouraged to enhance professional competence through reflective practice and they are also asked to undertake research to generate evidence for their professional practices. This paper reports on an inquiry into a group of primary school English language teachers’ research engagement in the province of Guangdong on the Chinese mainland. The inquiry explored the effect of educational reforms on the participants’ research engagement through the use of an open‐ended questionnaire and group interviews. The inquiry revealed that research engagement had become an important part of the teachers’ professional lives. Emerging findings from the inquiry also problematised their research engagement as it was found to have been undermined by a competitive promotion mechanism, the teachers’ conceptualisations of research and challenges in the knowledge dissemination process. The paper ends with reflections on how to make teacher research “educational” for teachers and serve as an effective way for professional development. 相似文献
165.
Lisa M. PytlikZillig Christy A. Horn Roger Bruning Stephanie Bell Xiongyi Liu Kamau O. Siwatu Mary C. Bodvarsson Doyoung Kim Deborah Carlson 《Contemporary educational psychology》2011,36(4):302-312
Two frequently-used discussion protocols were investigated as part of a program to implement teaching cases in undergraduate educational psychology classes designed for preservice teachers. One protocol involved synchronous face-to-face (FTF) discussion of teaching cases, which occurred in class after students had individually completed written case analyses as homework outside of class. The other was asynchronous computer-mediated (CM) discussion taking place outside of class, simultaneous to students’ completion of their written case analyses. Six class offerings of an undergraduate child development course taught by two instructors (three classes by each instructor) were randomly assigned within instructor in a quasi-experimental design to one of the three discussion conditions: FTF, CM, or no discussion of the cases across the semester. Findings indicated that both CM and FTF discussion conditions were associated with positive outcomes relative to the control condition. Both CM and FTF discussion related to higher cognitive–affective engagement with the cases than the control condition; and the CM discussion condition was associated with higher cognitive–affective engagement than FTF discussion. In contrast, FTF discussion, but not CM discussion, was associated with higher-than-control-condition case analysis ability at the end of the semester. Potential explanations for these findings and directions for future research are discussed. 相似文献
166.
167.
Robert B. Anderson Julius A. Marshall Andrea L’Afflitto 《Journal of The Franklin Institute》2021,358(12):6281-6308
In classical model reference adaptive control (MRAC), the adaptive rates must be tuned to meet multiple competing objectives. Large adaptive rates guarantee rapid convergence of the trajectory tracking error to zero. However, large adaptive rates may also induce saturation of the actuators and excessive overshoots of the closed-loop system’s trajectory tracking error. Conversely, low adaptive rates may produce unsatisfactory trajectory tracking performances. To overcome these limitations, in the classical MRAC framework, the adaptive rates must be tuned through an iterative process. Alternative approaches require to modify the plant’s reference model or the reference command input. This paper presents the first MRAC laws for nonlinear dynamical systems affected by matched and parametric uncertainties that constrain both the closed-loop system’s trajectory tracking error and the control input at all times within user-defined bounds, and enforce a user-defined rate of convergence on the trajectory tracking error. By applying the proposed MRAC laws, the adaptive rates can be set arbitrarily large and both the plant’s reference model and the reference command input can be chosen arbitrarily. The user-defined rate of convergence of the closed-loop plant’s trajectory is enforced by introducing a user-defined auxiliary reference model, which converges to the trajectory tracking error obtained by applying the classical MRAC laws before its transient dynamics has decayed, and steering the trajectory tracking error to the auxiliary reference model at a rate of convergence that is higher than the rate of convergence of the plant’s reference model. The ability of the proposed MRAC laws to prescribe the performance of the closed-loop system’s trajectory tracking error and control input is guaranteed by barrier Lyapunov functions. Numerical simulations illustrate both the applicability of our theoretical results and their effectiveness compared to other techniques such as prescribed performance control, which allows to constrain both the rate of convergence and the maximum overshoot on the trajectory tracking error of uncertain systems. 相似文献
168.
169.
170.
Sanjeev Shruthi Molly Mary Thabah Bobby Zachariah Vir Singh Negi 《Indian journal of clinical biochemistry : IJCB》2021,36(2):185
To study oxidative stress in systemic lupus erythematosus (SLE) by estimating serum oxidised LDL (OxLDL), 8-hydroxy-2′-deoxyguanosine (8-OHdG), malondialdehyde (MDA), and total anti-oxidant status and to correlate with SLE disease activity and disease damage. Eighty SLE patients satisfying the Systemic Lupus International Collaborating Clinics/American College of Rheumatology (SLICC/ACR) 2012 criteria and 80 healthy controls were studied. Exclusion criteria were infections, renal insufficiency, other connective tissue diseases, drug-induced lupus, smoking, alcohol consumption. Disease activity was measured by SLE disease activity index-2 K (SLEDAI), disease damage was quantified by SLICC-Damage Index (SDI). Sera was tested for OxLDL, 8-OHdG, and total antioxidant status (TAS) by double-antibody sandwich ELISA; MDA measured by Colorimetric assay. Oxidative stress markers were compared between group1- controls, group 2-mildly active SLE (SLEDAI ≤ 5), group 3- moderate to highly active SLE (SLEDAI ≥ 6). SLE patients had significantly higher MDA, 8-OHdG and lower TAS when compared to healthy controls, while OxLDL was similar in the three groups. MDA, 8-OHdG were significantly higher, TAS lower in group 3 compared to group 2. MDA had positive correlation with SLEDAI, TAS negatively correlated with SLEDAI. SLE with neuropsychiatric manifestations, vasculitis, anti-sdDNA antibodies had higher MDA, MDA/TAS ratio. SLE patients with thrombocytopenia, and vasculitis had higher OxLDL. Only OxLDL was significantly higher in those patients who have SDI > 1. SLE patients have increased oxidative stress measured by increases in MDA, 8-OHdG, and lower total antioxidant status that was associated with disease activity and some disease manifestations. However only OxLDL was associated with damage. 相似文献