全文获取类型
收费全文 | 15464篇 |
免费 | 186篇 |
国内免费 | 11篇 |
专业分类
教育 | 10583篇 |
科学研究 | 2014篇 |
各国文化 | 120篇 |
体育 | 1055篇 |
综合类 | 5篇 |
文化理论 | 102篇 |
信息传播 | 1782篇 |
出版年
2021年 | 160篇 |
2020年 | 210篇 |
2019年 | 311篇 |
2018年 | 475篇 |
2017年 | 420篇 |
2016年 | 406篇 |
2015年 | 250篇 |
2014年 | 389篇 |
2013年 | 2676篇 |
2012年 | 333篇 |
2011年 | 364篇 |
2010年 | 320篇 |
2009年 | 288篇 |
2008年 | 347篇 |
2007年 | 288篇 |
2006年 | 280篇 |
2005年 | 250篇 |
2004年 | 287篇 |
2003年 | 207篇 |
2002年 | 214篇 |
2001年 | 308篇 |
2000年 | 302篇 |
1999年 | 275篇 |
1998年 | 160篇 |
1997年 | 192篇 |
1996年 | 182篇 |
1995年 | 133篇 |
1994年 | 147篇 |
1993年 | 149篇 |
1992年 | 262篇 |
1991年 | 230篇 |
1990年 | 216篇 |
1989年 | 231篇 |
1988年 | 207篇 |
1987年 | 194篇 |
1986年 | 194篇 |
1985年 | 203篇 |
1984年 | 167篇 |
1983年 | 184篇 |
1982年 | 153篇 |
1981年 | 144篇 |
1980年 | 135篇 |
1979年 | 196篇 |
1978年 | 153篇 |
1977年 | 146篇 |
1976年 | 126篇 |
1975年 | 102篇 |
1974年 | 122篇 |
1973年 | 115篇 |
1972年 | 98篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
121.
122.
123.
In light of recent theories of meaningful media that suggest a host of psychological benefits, the present study uniquely extends the boundaries of the effects of reality TV from simply offering pleasure, diversion, and amusement to its viewers to also providing deep insight and meaning. In particular, a between-subjects experiment (N = 143) examined differences in affective, cognitive, and motivational responses to lifestyle transforming versus game based reality programs. Findings indicate that lifestyle transforming reality TV produced stronger feelings of elevation and perceptions of the program as moving and thought-provoking than game reality TV, which in turn increased motivations for altruism. Avenues for future research and theoretical implications of meaningful and inspiring reality TV for positive psychology are discussed. 相似文献
124.
V. K. Wadhawan 《Resonance》2005,10(11):27-41
A structure is an assembly that serves an engineering function. It is reasonable to expect that all engineering design should
be smart, and not dumb. But one can still make a distinction between smartly designed structures and smart structures. The
latter term has acquired a specific technical meaning over the last few decades. A smart structure is that which has the ability
to respond adaptively in a pre-designed useful and efficient manner to changes in environmental conditions, including any
changes in its own condition; the response is adaptive in the sense that two or more stimuli or inputs may be received as
anticipated and yet there is a single response function as per design. Smartness ensures that the structure gives optimum
performance under a variety of environmental conditions. While structures with some degree of smartness have been designed
from times immemorial, the current activity and excitement in this field derives its impetus from the level of sophistication
achieved in materials science, information technology, measurement science, sensors, actuators, signal processing, nanotechnology,
cybernetics, artificial intelligence, and biomimetics. 相似文献
125.
K. R. Shivanna 《Resonance》2016,21(11):1007-1018
After the pollen grain reaches the stigma through outsourced agents (pollinators), the next step before fertilization is to select the right type of pollen. Similar to a marriage in human beings, fiowering plants also have evolved elaborate screening process to select the right pollen grains and to reject the wrong ones. Even after initial screening for the right pollen, the pistil imposes a tough competition amongst them, comparable to a swayamvara of Indian mythology, to select the best available pollen. Flowering plants have evolved into a matriarchal society. The selection of the male partner is totally the prerogative of the mother (pistil); the boy (pollen grain) and the girl (ovule) has no say in this selection. 相似文献
126.
Daan Van De Pol Sena Alaeikhanehshir Mario Maas P. Paul F.M. Kuijer 《Journal of sports sciences》2016,34(12):1141-1147
The prevalence of ischaemia-related symptoms is remarkably high among elite indoor volleyball players. Since the exposure to sport-specific demands may be higher in beach volleyball compared to indoor volleyball, the aim of this study was to assess the prevalence of ischaemia-related symptoms and associated risk factors among world-class beach volleyball players. Therefore, a questionnaire survey was performed among beach volleyball players active during the 2013 Grand Slam Beach Volleyball in the Netherlands. In total, 60 of the 128 beach volleyball players (47%) participated: 26 males and 34 females from 17 countries. The self-reported prevalence of cold or blue or pale digits in the dominant hand during or immediately after practice or competition was 38% (n = 23). Two risk factors were independently associated with symptoms of blue or pale digits: more than 14 years playing volleyball (odds ratio (OR) 4.42, 90% confidence interval (90% CI) 1.30–15.07) and sex (female) (OR 4.62, 90% CI 1.15–18.57). In conclusion, the prevalence of symptoms associated with digital ischaemia is high among international world-class beach volleyball players. Female sex and the length of the volleyball career were independently associated with an increased risk of ischaemia-related symptoms. The high prevalence of these seemingly innocuous symptoms and possible associated risk factors warrant regular monitoring since early detection can potentially prevent thromboembolic complications and irreversible tissue damage. 相似文献
127.
Nicolas Milazzo Damian Farrow Alexis Ruffault Jean F. Fournier 《Journal of sports sciences》2016,34(16):1547-1556
This study examined the contribution of situational probability information to the perceptual and cognitive processes underlying decision-making behaviour during in situ Karate performance. Experts and novices were required to make decisions about various attacks in different fight scenarios. The order in which the fight situations were presented was modified in order to provide advanced probability information and identify whether fighters were able to use the latter information to make better decisions. Specifically, one of the attacks was repeated every four actions. Results revealed that experts were more accurate and faster than their less skilled counterparts to block and counterattack the opponent. The experts picked up the occurrence of the attack pattern after the fifth repetition whereas novices did not. This enabled experts to improve decision time and decision accuracy. Findings suggest that such superiority could stem from the perceptual and cognitive skills possessed by the experts, thus giving them the opportunity to recognise a situation more easily. This was reinforced by gaze behaviour which demonstrated that experts used a more efficient search strategy involving fewer fixations of longer duration on a lesser number of areas relative to the novices. Moreover, experts generated more refined karate-specific knowledge structures compared with the novices. 相似文献
128.
Erin K. Howie Joanne A. McVeigh Rebecca A. Abbott Tim S. Olds Leon M. Straker 《Journal of sports sciences》2016,34(16):1581-1587
Fitness is an important component of health, and obese adolescents regularly have poor fitness. Unfortunately, few have assessed the impact of community-based lifestyle interventions on multiple components of fitness. The purpose of this study was to assess the impact of participation in a community-based intervention involving adolescents and parents on multiple components of fitness of obese adolescents. In a within-subject, waitlist controlled clinical trial with 12 months follow-up in Western Australia, participants (n = 56) completed multiple fitness measures at baseline, immediately prior to beginning an 8-week intervention and at 3, 6 and 12 months during a maintenance period. Performance on the shuttle walk was improved immediately post-intervention (increase of 42.8 m, 95% CI: 7.5, 78.2) and at 12 months post-intervention (increase of 44.6 m, 95% CI: 1.3, 87.8) compared with pre-intervention. Muscle performance of quadriceps and deltoids were improved post-intervention (increase of 1.1 (95% CI: 0.1, 2.1) kg · F and 1.0 (0.02, 2.1) kg · F, respectively) and all muscle performance measures were improved at 12 months following the intervention. There were no changes in waist circumference. A community-based lifestyle programme such as Curtin University’s Activity, Food and Attitudes Program (CAFAP) may be a viable strategy for improving fitness in overweight adolescents. 相似文献
129.
Jordan J. Smith Philip J. Morgan Ronald C. Plotnikoff David F. Stodden David R. Lubans 《Journal of sports sciences》2016,34(8):772-779
The purpose of this study was to examine the mediating effect of resistance training skill competency on percentage of body fat, muscular fitness and physical activity among a sample of adolescent boys participating in a school-based obesity prevention intervention. Participants were 361 adolescent boys taking part in the Active Teen Leaders Avoiding Screen-time (ATLAS) cluster randomised controlled trial: a school-based program targeting the health behaviours of economically disadvantaged adolescent males considered “at-risk” of obesity. Body fat percentage (bioelectrical impedance), muscular fitness (hand grip dynamometry and push-ups), physical activity (accelerometry) and resistance training skill competency were assessed at baseline and post-intervention (i.e., 8 months). Three separate multi-level mediation models were analysed to investigate the potential mediating effects of resistance training skill competency on each of the study outcomes using a product-of-coefficients test. Analyses followed the intention-to-treat principle. The intervention had a significant impact on the resistance training skill competency of the boys, and improvements in skill competency significantly mediated the effect of the intervention on percentage of body fat and the combined muscular fitness score. No significant mediated effects were found for physical activity. Improving resistance training skill competency may be an effective strategy for achieving improvements in body composition and muscular fitness in adolescent boys. 相似文献
130.
Matteo Zago Andrea Gianluca Piovan Isabella Annoni Daniela Ciprandi F. Marcello Iaia 《Journal of sports sciences》2016,34(5):411-419
Dribbling speed in soccer is considered critical to the outcome of the game and can assist in the talent identification process. However, little is known about the biomechanics of this skill. By means of a motion capture system, we aimed to quantitatively investigate the determinants of effective dribbling skill in a group of 10 Under-13 sub-elite players, divided by the median-split technique according to their dribbling test time (faster and slower groups). Foot-ball contacts cadence, centre of mass (CoM), ranges of motion (RoM), velocity and acceleration, as well as stride length, cadence and variability were computed. Hip and knee joint RoMs were also considered. Faster players, as compared to slower players, showed a 30% higher foot-ball cadence (3.0 ± 0.1 vs. 2.3 ± 0.2 contacts · s?1, P < 0.01); reduced CoM mediolateral (0.91 ± 0.05 vs. 1.14 ± 0.16 m, P < 0.05) and vertical (0.19 ± 0.01 vs. 0.25 ± 0.03 m, P < 0.05) RoMs; higher right stride cadence (+20%, P < 0.05) with lower variability (P < 0.05); reduced hip and knee flexion RoMs (P < 0.05). In conclusion, faster players are able to run with the ball through a shorter path in a more economical way. To effectively develop dribbling skill, coaches are encouraged to design specific practices where high stride frequency and narrow run trajectories are required. 相似文献