首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   526篇
  免费   15篇
  国内免费   1篇
教育   325篇
科学研究   132篇
各国文化   5篇
体育   31篇
综合类   4篇
文化理论   5篇
信息传播   40篇
  2023年   9篇
  2022年   10篇
  2021年   22篇
  2020年   12篇
  2019年   32篇
  2018年   31篇
  2017年   43篇
  2016年   23篇
  2015年   23篇
  2014年   33篇
  2013年   64篇
  2012年   37篇
  2011年   22篇
  2010年   27篇
  2009年   22篇
  2008年   25篇
  2007年   14篇
  2006年   9篇
  2005年   12篇
  2004年   10篇
  2003年   11篇
  2002年   11篇
  2001年   6篇
  2000年   7篇
  1999年   1篇
  1997年   1篇
  1996年   2篇
  1995年   1篇
  1993年   2篇
  1992年   2篇
  1991年   3篇
  1990年   2篇
  1989年   2篇
  1988年   1篇
  1987年   1篇
  1985年   1篇
  1984年   1篇
  1983年   1篇
  1980年   1篇
  1978年   1篇
  1976年   1篇
  1975年   1篇
  1970年   1篇
  1967年   1篇
排序方式: 共有542条查询结果,搜索用时 15 毫秒
461.
We examined the influence of caffeine supplementation on cognitive performance and perceptual responses in female team-game players taking low-dose monophasic oral contraceptives of the same hormonal composition. Ten females (24 ± 4 years; 59.7 ± 3.5 kg body mass; 2–6 training sessions per week) took part in a randomised, double-blind, placebo-controlled crossover-design trial. A 90-min intermittent treadmill-running protocol was completed 60 min following ingestion of a capsule containing either 6 mg ? kg?1 anhydrous caffeine or artificial sweetener (placebo). Perceptual responses (ratings of perceived exertion (RPE), feeling scale (FS), felt arousal scale (FAS)), mood (profile of mood states (POMS)) and cognitive performance (Stroop test, choice reaction time (CRT)) were completed before, during and after the exercise protocol, as well as after ~12 h post exercise. Caffeine ingestion significantly enhanced the ratings of pleasure (= 0.008) and arousal (= 0.002) during the exercise protocol, as well as increased vigour (POMS; = 0.007), while there was a tendency for reduced fatigue (POMS; = 0.068). Caffeine ingestion showed a tendency to decrease RPE (= 0.068) and improve reaction times in the Stroop (= 0.072) and CRT (= 0.087) tests. Caffeine supplementation showed a positive effect on perceptual parameters by increasing vigour and a tendency to decrease fatigue during intermittent running activity in female games players taking low-dose monophasic oral contraceptive steroids (OCS).  相似文献   
462.
The well-known detrimental effects of cadmium (Cd) on plants are chloroplast destruction, photosynthetic pigment inhibition, imbalance of essential plant nutrients, and membrane damage. Jasmonic acid (JA) is an alleviator against different stresses such as salinity and drought. However, the functional attributes of JA in plants such as the interactive effects of JA application and Cd on rapeseed in response to heavy metal stress remain unclear. JA at 50 μmol/L was observed in literature to have senescence effects in plants. In the present study, 25 μmol/L JA is observed to be a “stress ameliorating molecule” by improving the tolerance of rapeseed plants to Cd toxicity. JA reduces the Cd uptake in the leaves, thereby reducing membrane damage and malondialdehyde content and increasing the essential nutrient uptake. Furthermore, JA shields the chloroplast against the damaging effects of Cd, thereby increasing gas exchange and photosynthetic pigments. Moreover, JA modulates the antioxidant enzyme activity to strengthen the internal defense system. Our results demonstrate the function of JA in alleviating Cd toxicity and its underlying mechanism. Moreover, JA attenuates the damage of Cd to plants. This study enriches our knowledge regarding the use of and protection provided by JA in Cd stress.  相似文献   
463.
This study investigates how teachers and students assess the textbooks they use in history courses at the high school level in Turkey. Through a survey questionnaire, teachers and students were asked their perceptions of the textbooks. Then a sub-sample of the teachers and students were interviewed to collect more in-depth data on their assessment of the textbooks. The results indicated that the textbooks assist the teacher in instructional planning and in preparing exams, and help the students deal with the content. However, both teachers and students point to problems in textbooks in terms of their physical aspects, content presentation and organization, language, teaching and learning aids, and their impact on students. The textbooks focus mostly on transmission of knowledge, and they are found ineffective in leading students to read the information with interest and develop an understanding of the content area. They are found ineffective in developing students’ thinking skills and positive attitudes toward the subject.  相似文献   
464.
ABSTRACT

This investigation examined the consequences and effects of the severity of mothers psychosocial functioning as assessed by measures parenting stress and depression in a randomised control trial of a Relationship-based Intervention (RBI) called Responsive Teaching (RT). The sample included 28 parents and preschool aged children with Autism from Saudi Arabia. RT subjects received weekly parent–child intervention sessions for 4 months. Dependent variables were mothers’ style of interaction as assessed by the PICCOLO at post intervention as well as pre- and post-measures of parenting stress and depression. There were three findings from this study. First, mothers who participated in this study had extremely high levels of psychosocial dysfunction. Nearly all reported clinical levels of parenting stress and more than 40% reported clinical levels of depressive symptoms. Second, high levels of psychosocial dysfunction did not prevent mothers from participating in RT as indicated by their ability to integrate RT strategies into their interactions with their children. Third, RT was associated with substantial improvements in mother’s parenting stress and depression. Implication for early intervention practice are discussed.  相似文献   
465.
This study examines the multidimensional and hierarchical structure of achievement goal orientation measured by the Inventory of School Motivation. The instrument consists of eight different scales with 43 survey items (ranging from three to seven items each). Each scale reflects one of eight specific dimensions: task, effort, competition, social power, affiliation, social concern, praise, and token. The study also examines the ability of these eight first‐order factors to define four general second‐order factors—mastery, performance, social factors, and extrinsic factors—as well as one third‐order factor, general motivation. Participants came from seven different cultural groups in high schools in Australia (n = 4,787), Hong Kong (n = 697), the United States (n = 2,660), and Africa (n = 819). Nested confirmatory factor analyses support a multidimensional, hierarchical school motivation construct. The model was invariant across cultural groups. The findings provide a strong theoretical structure and tool for further school motivation research.  相似文献   
466.
This research investigates the personality characteristics of Information Technology students (CIT) in UAE University (UAEU) and how such features impact their IT learning. To achieve this objective, this research attempts to explain the impact of the Big-5 factors on learning using survey research. Results from 179 respondents suggested that agreeableness, extraversion, openness, and conscientiousness respectively were the most important strategies adopted by CIT students. However, neuroticism scored the lowest. Such results could be attributed to personal as well as to cultural reasons as highlighted in this research. The research highlights theoretical as well as professional contributions and implications. Some of challenges in this research could be addressed by designing programs aiming at enhancing student’s learning ability from the perspective of their personal traits.  相似文献   
467.
Test assembly is the process of selecting items from an item pool to form one or more new test forms. Often new test forms are constructed to be parallel with an existing (or an ideal) test. Within the context of item response theory, the test information function (TIF) or the test characteristic curve (TCC) are commonly used as statistical targets to obtain this parallelism. In a recent study, Ali and van Rijn proposed combining the TIF and TCC as statistical targets, rather than using only a single statistical target. In this article, we propose two new methods using this combined approach, and compare these methods with single statistical targets for the assembly of mixed‐format tests. In addition, we introduce new criteria to evaluate the parallelism of multiple forms. The results show that single statistical targets can be problematic, while the combined targets perform better, especially in situations with increasing numbers of polytomous items. Implications of using the combined target are discussed.  相似文献   
468.
The literature supports the importance of parenting styles that are necessary to fulfill the developmental needs of the children and eventually improve their quality of life. Baumrind’s typology of parenting styles was used. There are many studies that examined the relationship of parenting styles (authoritative, authoritarian and permissive parenting styles) and academic performance, but there is lack of measurement of the relationship with respect to Pakistan. Current study analyzed the relationship of parenting styles and academic performance along with self-efficacy as mediating variable. Sample of the study consists of 313 university students from four academic departments. Measures included the parenting styles and self-efficacy. GPA was taken as a measure of academic performance of adolescents. Self-reported questionnaire was used to take the response from students. With the help of structural equation modeling, structural model was tested. Results of the study indicate that parenting styles individually have no significant relationship with the academic performance. In addition to this, self-efficacy only mediates the relationship of authoritative parenting style and academic performance. It can be concluded that self-efficacy in individuals is an important attribute necessary for the psychological development of the adolescents. Self-efficacy enhances the individual’s confidence to progress. There is a need to conduct more research on the relationship of parenting styles and academic performance in Pakistan. Implications for parents, teachers, are discussed.  相似文献   
469.
This study investigates the assessment strategies used in social-studies courses at the high-school level in Turkey and examines how teachers and students perceive them. Results indicate that short-answer tests are most frequently used to assess student performance, followed by oral tests. Multiple-choice and essay tests are also occasionally employed. Teachers tend to be satisfied with these assessment strategies, but suggest that alternative modes of assessment should also be considered. Students do not find such tests adequate for assessing their real performance in social-studies courses.  相似文献   
470.
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号