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131.
132.
The German education system does not traditionally rely on standardized testing. However, when the Programme for International Student Assessment (PISA) study revealed an average performance of German students compared to other participating countries, a particular proportion of low-performing students, and remarkable disparities between the federal states, German policy makers decided for a major reform of the education system. A core piece of this reform was the introduction of National Education Standards. For science education, these standards were heavily influenced by the PISA results and its underlying framework. That is, with the standards, a paradigm shift took place from the German notion of Bildung towards the Anglo-American notion of literacy. With the introduction of these standards, a new field of empirical educational research was created: research on models of scientific literacy or competency models as a basis of benchmarking the standards. This article describes the German education system before PISA, summarizes the major findings from PISA, and describes how these findings informed the formulation of the performance standards for science education. It also details the measures undertaken to benchmark these standards. Finally, it provides insight into the issues with developing and benchmarking performance standards and points out future areas of research on evidence-based decision making in educational policy.  相似文献   
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Training consisting of numerous repetitions performed as closely as possible to ideal techniques is common in sports and every-day tasks. Little is known about fatigue-related technique changes that emerge at different timescales when repeating complex actions such as a karate front kick. Accordingly, 15 karatekas performed 600 kicks (1 pre-block and 9 blocks). The pre-block comprised 6 kicks (3 with each leg) at maximum intensity (K-100%). Each block comprised 60 kicks (10 with each leg) at 80% of their self-perceived maximum intensity (K-80%) plus 6 K-100%. In between blocks, the participants rested for 90 seconds. Right leg kinematics (peak joint angles, peak joint angular velocities, peak joint linear resultant velocities, and time of occurrence of peaks) and kick duration corresponding to the K-80% were measured resulting in numerous variations with fatigue. At the timescale of tens of seconds, the changes involved variables that were related to velocity of execution (slowed down), while variables related to movement form were hardly affected. At the timescale of tens of minutes, the opposite results were observed. These findings challenge the long-standing rationale underlying repetitive training, suggesting instead that such involuntary variations in technique might play a crucial role in motor skill training  相似文献   
135.

Background

The purpose of this study was to analyze the relationship between performance test parameters and match-related physical performance in professional soccer players.

Methods

To determine physical capacity, 28 male soccer players underwent several performance tests at the start of the seasons 2013/2014, 2014/2015, and 2015/2016. The following parameters were assessed: maximum running velocity (vmax), fixed (v4mmol/l) and individual anaerobic threshold (vIAS) during an incremental treadmill test; 30-m sprint time in a linear sprint test (LS30m); in a repeated-sprint test, the 30-m sprint time (RST30m) and performance decrement (RSTdecr); and countermovement jump height (CMJ). Match physical performance was quantified during the first ten official matches of each season using a computerized, camera-based tracking system. The following measures of match physical performance were considered: top running speed (TS), mean running speed (vØ), total distance covered (TD), number of sprints (SP), number of high-intensity running (HIR), and aerial duels won (AD+). Pearson correlation coefficients were used for statistical analysis.

Results

Moderate to very large correlations were found between the majority of performance test parameters and match performance variables, with a variability of correlations across the three seasons. Large relationships across all three seasons were only observed between vmax and TD, vmax and vØ, LS30m and TS as well as RST30m and TS.

Conclusion

This study demonstrates the relationship between several performance test parameters and match-related physical performance in professional soccer players, thereby supporting the test parameters’ criterion validity. vmax, LS30m, and RST30m seem to be the most consistent parameters.
  相似文献   
136.
Purpose: There is currently no standardized testing protocol for assessing clients’ fitness/health within the Australian fitness industry. This study examined the perceptions of the feasibility of using a standardized testing protocol among Australian fitness industry professionals. Method: In 2014, 1,206 registered fitness industry professionals (aged 17–69 years) completed an online survey. Perceived feasibility for using a standardized testing protocol was assessed based on responses to 6 items. Respondents were classified as having a high level of perceived feasibility if they reported all 6 items to be “definitely feasible.” A multivariate logistic regression analysis, adjusting for demographic and fitness industry-related factors (e.g., qualification/years of experience), assessed the likelihood of having a high level of perceived feasibility. Results: Overall, 25.5% (95% CI [23.1%, 28.0%]) of the sample perceived the use of a standardized testing protocol as highly feasible. Items ranked most often as “definitely feasible” were “undertaking training to use the protocol” (55%) and “conducting follow-up testing every 6 to 12 weeks” (52%). After adjustment for the effect of confounding factors, casually employed professionals (OR = 0.63; 95% CI [0.45, 0.90]) and group instructors (OR = 0.58; 95% CI [0.41, 0.82]) were less likely to perceive standardized testing protocols as highly feasible. Conclusions: Among a large sample of Australian fitness industry professionals, slightly more than a quarter perceived using a standardized testing protocol to be highly feasible. Group instructors and casual employees perceived lower feasibility. Further research should determine the barriers to implementing a standardized testing protocol across the fitness industry.  相似文献   
137.
We report a facile and robust microfluidic method to fabricate polymeric core-shell microspheres as delivery vehicles for biomedical applications. The characteristics of core-shell microspheres can be precisely and easily tuned by manipulating the microfluidic double emulsion templates. The addition of a shell can significantly improve the versatility as well as functionality of these microspheres as delivery vehicles. We demonstrate that the nature of the shell material plays an important role in the properties of the core-shell delivery vehicles. The release kinetics is significantly influenced by the material of the shell and other characteristics such as the thickness. For example, by adding a poly(lactic-co-glycolic acid) (PLGA) shell to an alginate core, the encapsulation efficiency is enhanced and undesired leakage of hydrophilic actives is prevented. By contrast, adding an alginate shell to PLGA core can lead to a reduction of the initial release rate, thus extending the release period of hydrophobic actives. Microfluidic fabrication enables the generation of precisely controlled core-shell microspheres with a narrow size distribution, which enables the investigation of the relationship between the release kinetics of these microspheres and their characteristics. The approach of using core-shell particles as delivery vehicles creates new opportunities to customize the release kinetics of active ingredients.  相似文献   
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139.
Abstract

This study was conducted to validate and evaluate the “Hit & Turn Tennis Test”, an acoustically progressive on-court endurance test for tennis players. Ninety-eight competitive tennis players (53 males, 45 females) of different age groups participated in the study. For validation, the adult male players completed three Hit & Turn tests, one on a clay court and two on a carpet surface, a tennis-specific ball machine test and an incremental treadmill run in a randomized order. A stronger correlation between maximal performance (r = 0.81, P < 0.01) and maximal oxygen uptake (r = 0.96, P < 0.01) was observed between the Hit & Turn test and the ball machine test, than between the Hit & Turn test and the treadmill test. For test–retest, we found a significant correlation between maximal performance on the same (r = 0.83, P < 0.01) and on different surfaces (r = 0.74, P < 0.01). During test evaluation, maximal performance was higher in males than in females (P < 0.01) and increased by consecutive age group in boys (P < 0.01) but not in girls (P = 0.97). In conclusion, Hit & Turn maximum test performance can be recommended as a valid and reliable indicator for tennis-specific endurance.  相似文献   
140.
Abstract

We examined differences in anthropometry and training between 64 Triple Iron ultra-triathletes competing over 11.4 km swimming, 540 km cycling, and 126.6 km running, and 71 Ironman triathletes competing over 3.8 km swimming, 180 km cycling, and 42.2 km running. The association of anthropometry and training with race time was investigated using multiple linear regression analysis. The Triple Iron ultra-triathletes were smaller (P < 0.05), had shorter limbs (P < 0.05), a higher body mass index (P < 0.05), and larger limb circumferences (P < 0.01) than the Ironman triathletes. The Triple Iron ultra-triathletes trained for more hours (P < 0.01) and covered more kilometres (P < 0.01), but speed in running during training was slower compared with the Ironman triathletes (P < 0.01). For Triple Iron ultra-triathletes, percent body fat (P = 0.022), training volume per week (P < 0.0001), and weekly kilometres in both cycling (P < 0.0001) and running (P < 0.0001) were related to race time. For Ironman triathletes, percent body fat (P < 0.0001), circumference of upper arm (P = 0.006), and speed in cycling training (P = 0.012) were associated with total race time. We conclude that both Triple Iron ultra-triathletes and Ironman triathletes appeared to profit from low body fat. Triple Iron ultra-triathletes relied more on training volume in cycling and running, whereas speed in cycling training was related to race time in Ironman triathletes.  相似文献   
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