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971.
Abstract

The aim of this study was to examine stressors, coping, and coping effectiveness as a function of gender, type of sport, and skill. The sample consisted of 749 undergraduate athletes (455 males, 294 females) aged 18 – 38 years (mean = 19.8 years). Skill was classified as international/national, county, university, and club standard. Participants completed a stressor and coping concept map (Novak & Gowin, 1984 Novak, J. D. and Gowin, D. B. 1984. Learning how to learn, Cambridge: Cambridge University Press. [Crossref] [Google Scholar]). The results revealed gender, type of sport, and skill differences in relation to stressor frequencies, coping strategy deployment, and coping effectiveness. In contrast to previous research, females used a variety of problem-focused (e.g. planning, communication, technique-orientated coping) strategies more frequently than males. Team sport athletes reported a variety of sport-specific stressors relating to the demands of playing in a team environment. The group of national/international athletes reported using more planning, blocking, and visualization, and also reported that their coping was more effective than that of less-skilled athletes.  相似文献   
972.
Abstract

The badminton serve requires great skill and may be affected by fatigue. The aim of the present study was to determine whether carbohydrate ingestion affects badminton performance. Nine male badminton players (age 25 ± 7 years, mass 80.6 ± 8.0 kg) attended the laboratory on three occasions. The first visit involved an incremental exercise test to exhaustion to determine peak heart rate. Participants were given 1 L of a carbohydrate-electrolyte drink or a matched placebo during the experimental trials. The accuracy of 10 long and 10 short serves was determined before and after exercise. The fatiguing exercise was 33 min in duration (83 ± 10% and 84 ± 8% peak heart rate for the placebo and carbohydrate trial respectively). Capillary blood samples (20 μL) were taken before and after exercise for determination of blood glucose and lactate. There was deterioration in long serve accuracy with fatigue (P = 0.002), which carbohydrate ingestion had a tendency to prevent (P = 0.077). There was no effect of fatigue (P = 0.402) or carbohydrate ingestion (P = 0.109) on short serve accuracy. There was no difference in blood glucose concentration between trials (P = 0.851). Blood lactate concentration was higher during the placebo trial (P = 0.016). These results suggest that only the long serve is influenced by fatigue and carbohydrate had a tendency to prevent the deterioration in performance.  相似文献   
973.
Abstract

Mountain biking is a popular recreational pursuit and the physiological demands of cross-country style riding have been well documented. However, little is known regarding the growing discipline of gravity-assisted downhill cycling. We characterised the physiological demands of downhill mountain biking under typical riding conditions. Riding oxygen consumption ([Vdot]O2) and heart rate (HR) were measured on 11 male and eight female experienced downhill cyclists and compared with data during a standardised incremental to maximum ([Vdot]O2max) exercise test. The mean [Vdot]O2 while riding was 23.1 ± 6.9 ml · kg?1 · min?1 or 52 ± 14% of [Vdot]O2max with corresponding heart rates of 146 ± 11 bpm (80 ± 6% HRmax). Over 65% of the ride was in a zone at or above an intensity level associated with improvements in health-related fitness. However, the participants’ heart rates and ratings of perceived exertion were artificially inflated in comparison with the actual metabolic demands of the downhill ride. Substantial muscular fatigue was evident in grip strength, which decreased 5.4 ± 9.4 kg (5.5 ± 11.2%, P = 0.03) post-ride. Participation in downhill mountain biking is associated with significant physiological demands, which are in a range associated with beneficial effects on health-related fitness.  相似文献   
974.
In this exploratory study, the rater reliability of the Physical Education Observation Instrument (PEOI) was satisfactorily established. Three raters coded the frequency of occurrences of selective teacher (9) and student (4) behaviors and one catchall category when male teachers were instructing male pupils in volleyball. A 3 Rater × 3 Teacher × 2 Occasion Generalizability Study design indicated high stability of both inter- and intra-rater scores on 13 of 14 variables from ěp 2 .65 to .99, establishing the appropriateness of the PEOI for further observational research on teacher and student behaviors in physical education.  相似文献   
975.

Purpose: The relationships among students' self-efficacy, 2 × 2 achievement goals (mastery-approach [MAp], mastery-avoidance [MAv], performance-approach [PAp], and performance-avoidance goals), and achievement performance remain largely unanswered. We tested a model of the mediating role of self-efficacy on the relationship between 2 × 2 achievement goals and cardiorespiratory fitness. Method: A sample of 276 middle school students (115 boys and 161 girls; 91 sixth graders, 87 seventh graders, and 98 eighth graders), aged 12 to 15 years (M age = 13.34, SD = 0.96), responded to the Achievement Goals Questionnaire (Conroy, Elliot, &; Hofer, 2003) and Self-Efficacy Questionnaire (Gao, Newton, &; Carson, 2008) referenced to the fitness test. Their cardiorespiratory fitness was assessed via the Progressive Aerobic Cardiorespiratory Endurance Run (PACER) 3 days later. Results: Structural equation modeling demonstrated an acceptable model fit to the data, χ 2 (2, N = 105) = 1.66. Self-efficacy had a statistically significant direct effect on the PACER after controlling for the effects of the achievement goals (γ self-efficacy-PACER  = .21). MAv and PAp also had direct effects on PACER performance (γ MAv-PACER  = ? .24, and γ PAp-PACER  = .24, respectively). MAp failed to exert direct effect on the PACER. However, the indirect effect of MAp on the PACER via self-efficacy was small although it was statistically significant. Additionally, the indirect effects of MAv and PAp on PACER through self-efficacy were not significant. Conclusions: Students' self-efficacy fully mediated the effect of MAp on fitness performance, as well as partially mediated the effects of MAv and PAp on cardiorespiratory fitness performance. Study implications are provided for educators and practitioners.  相似文献   
976.
Ranking systems such as The Times Higher Education’s World University Rankings and Shanghai Jiao Tong University’s Academic Rankings of World Universities simultaneously mark global status and stimulate global academic competition. As international ranking systems have become more prominent, researchers have begun to examine whether global rankings are creating increased inequality within and between universities. Using a panel Tobit regression analysis, this study assesses the extent to which markers of inter-institutional stratification and organizational segmentation predict global status among US research universities as measured by position in ARWU. Findings indicate some support that both inter-institutional stratification and organizational segmentation predict global status.  相似文献   
977.
The main goal of this paper is to propose a dynamic mapping for knowledge and ignorance mobilization in science research and innovation. An underlying argument is that ‘knowledge mobilization’ science policy agendas in countries such as Canada and the United Kingdom fail to capture a critical element of science and innovation: ignorance mobilization. The latter draws attention to dynamics upstream of knowledge in science research and innovation. Although perhaps less visible, there is ample evidence that researchers value, actively produce, and thereby mobilize ignorance. For example, scientists and policymakers routinely mobilize knowledge gaps (cf. ignorance) in the process of establishing and securing research funding to argue the relevance of a scientific paper or a presentation, and to launch new research projects. Ignorance here is non-pejorative and by and large points to the borders and the limits of scientific knowing – what is known to be unknown. In addition, processes leading to the intentional or unintentional consideration or bracketing out of what is known to be unknown are intertwined with, yet remain distinct from, knowledge mobilization dynamics. The concepts of knowledge mobilization and of ignorance mobilization, respectively, are understood to be the use of knowledge or ignorance towards the achievement of goals. The value of this paper lies in its conceptualization of the mobilization of knowledge as related to the mobilization of ignorance within a complex, dynamic and symbiotic relationship in science research and innovation: it takes two to tango.  相似文献   
978.

Inquiry-based science instruction (IBSI) has the potential to contribute to social justice through widening participation and success in science. However, teachers struggle to implement IBSI because of contextual factors. The purpose of this paper is to explore the use of agency as a framework for understanding teachers’ decision-making, by asking the question: what was the agency of six science teachers in their social-justice aspirations and use of IBSI? An agency framework recognizes that teachers’ decisions are informed by their internal conversations at the intersection of personal aspects (their history, repertoire, and aspirations) with the cultural and structural constraints and resources of their contexts. However, research on IBSI has focussed on teachers’ personal aspects or their perceptions of contextual factors. The sample had learnt IBSI through service learning in the context of a science fair. From teacher interviews, it emerged that these teachers had strong social-justice aspirations to serve disadvantaged students. The teachers linked their social-justice aspirations to their choice of school rather than their use of IBSI. The teachers at better-resourced schools initiated participation in science fairs at their schools, whilst the rest judged that science fairs were not appropriate for their students. The results suggest that, rather than prescribing particular pedagogies, teacher education programmes should aim to increase teachers’ pedagogical repertoires, in order to enrich their agency in whatever contexts they teach.

  相似文献   
979.
Research in Higher Education - In 2015, Idaho adopted the nation’s first direct admissions system and proactively admitted all high school graduates to a set of public institutions. This...  相似文献   
980.
Many medical schools have undergone curricular reform recently. With these reforms, time spent teaching anatomy has been reduced, and there has been a general shift to a pass/fail grading system. At Indiana University School of Medicine (IUSM), a new curriculum was implemented in fall 2016. The year-long human gross anatomy course taught in 2015 was condensed into an integrated, semester-long course starting in 2016. Additionally, the grading scale shifted to pass/fail. This study examined first-year medical student performance on anatomy practical laboratory examinations—specifically, among lower-order (pure identification) questions and higher-order (function, innervation) questions. Participants included medical students from a pre-curricular reform cohort (year 2015, 34 students) and two post-curricular reform cohorts (years 2016, 30 students and 2017, 33 students). A Kruskal–Wallis ANOVA test was used to determine differences of these questions among the three cohorts. Additionally, 40 of the same lower-order questions that were asked on gross anatomy laboratory examinations from medical student cohort year 2015 and year 2016 were further analyzed using an independent samples t-test. Results demonstrated that the pre-curricular reform cohort scored significantly higher on both lower-order (median = 81, p < 0.001) and higher-order questions (median = 82.5, p < 0.05) than both post-curricular reform cohorts. Additionally, when reviewing the selected 40 similar questions, it was found that the pre-curricular reform cohort averaged significantly higher (82.1 ± 16.1) than the post-curricular reform cohort from 2016 (69.3 ± 21.8, p = 0.004). This study provides evidence about the impact of curricular reform on medical student anatomical knowledge.  相似文献   
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