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排序方式: 共有8844条查询结果,搜索用时 15 毫秒
241.
242.
Grant R. Tomkinson Tetsuhiro Kidokoro Trevor J. Dufner Shingo Noi John S. Fitzgerald Holly M. Brown-Borg 《运动与健康科学(英文)》2021,10(4):462-469
BackgroundThe 6-minute walking distance (6MWD) is an excellent measure of both functional endurance and health. The primary aim of this study was to estimate temporal trends in 6MWD for older Japanese adults between 1998 and 2017; the secondary aim was to estimate concurrent trends in body size (i.e., height and mass) and self-reported participation in exercise/sport.MethodsAdults aged 65–79 years were included. Annual nationally representative 6MWD data (n = 103,505) for the entire period were obtained from the Japanese Ministry of Education, Culture, Sports, Science and Technology. Temporal trends in means (and relative frequencies) were estimated at the gender–age level by best-fitting sample-weighted linear/polynomial regression models, with national trends estimated by a post-stratified population-weighting procedure. Temporal trends in distributional variability were estimated as the ratio of coefficients of variation.ResultsBetween 1998 and 2017 there was a steady, moderate improvement in mean 6MWD (absolute = 45 m (95% confidence interval (95%CI): 43–47); percent = 8.0% (95%CI: 7.6%–8.4%); effect size = 0.51 (95%CI: 0.48–0.54)). Gender- and age-related temporal differences in means were negligible. Variability in 6MWD declined substantially (ratio of coefficients of variation = 0.89, 95%CI: 0.87–0.92), with declines larger for women compared to men, and for 75–79-year-olds compared to 65–74-year-olds. Correspondingly, there were moderate and negligible increases in mean height and mass, respectively, and negligible increases in the percentage who participated in exercise/sport at least 3 days per week and at least 30 min per session.ConclusionThere has been a steady, moderate improvement in mean 6MWD for older Japanese adults since 1998, which is suggestive of corresponding improvements in both functional endurance and health. The substantial decline in variability indicates that the temporal improvement in mean 6MWD was not uniform across the distribution. Trends in 6MWD are probably influenced by corresponding trends in body size and/or participation in exercise/sport. 相似文献
243.
Joy Patricia Burke Caroline E. Haworth John C. Brantley 《Psychology in the schools》1983,20(2):191-196
To identify professional groups that are providing psychological services in the schools, the present national survey of state departments of education was conducted. Fifty-nine percent of states currently mandate services of school psychologists by law, and a variety of allied professional groups were identified as also providing psychological services in the schools. Specific information about provider groups and service mandates is reported. Recommendations relevant to the provision of quality school-psychological services and utilization of multiple providers are given. 相似文献
244.
245.
This article describes the development, utilization, and evaluation of an early screening battery for predicting school success or failure. The battery was administered to the pediatric population of the Southern California Permanente Medical Group, Panorama City Medical Center, at the time of the routine five-year health examination. For 411 children whose school performance was assessed by the teacher at age seven years, the Caldwell Test was the best predictor, but it had significant value for girls only (p<0.0001). In 1,251 children evaluated at age nine years, the Beery-Butkenica Developmental Test of Visual-Motor Integration (VMI) and the Caldwell Test were the best predictors (p⩽0.003). In 600 children for whom we had teacher ratings at ages seven and nine years, the VMI repeated at age seven years significantly predicted academic achievement and reading at age nine years for girls and boys (p = 0.007). Although combining the academic performance with VMI results at age seven years yielded 89% accuracy of prediction at age nine years, the false-positive rate represents a serious practical problem of mislabeling children as school failures. 相似文献
246.
Three experiments examined repeated retention testing effects in a contextual interference (CI) protocol. Retention was assessed at 10 min and 24 hr following acquisition or at just 24-hr for the one-test conditions. Experiments 1 and 2 used speeded-response key-pressing tasks. Dependent measures were total time and errors. Experiment 3 used sequential-timing tasks. Dependent measures were absolute error and absolute constant error Results revealed CI effects in each experiment. Repeated retention testing effects were not found in Experiments 1 and 3. Experiment 2 revealed superior performance by the two-test condition compared to the one-test condition. This result was qualified by possible practice effects during the 10-min test. It was concluded that repeated retention testing does not present problems for most studies of CI. 相似文献
247.
Geographic clustering of economic activity: The case of prominent western visual artists 总被引:1,自引:1,他引:0
This article compiles original data relating to artists’ place of birth and work migration patterns using various art history
dictionaries. The broad historic pattern, from the 13th to the 20th century, of the birth locations of prominent artists is examined, followed
by a detailed study of the work migration patterns of prominent artists in two important situations, namely Renaissance Italy
and France in part of the 19th century. The evidence indicates a marked clustering of activity of prominent artists, both
arising from birth location and migration patterns. Some possible explanations for the observed patterns are briefly outlined.
相似文献
John O’HaganEmail: |
248.
The aim of this study was to determine whether 3 weeks of intermittent normobaric hypoxic exposure at rest was able to elicit changes that would benefit multi-sport athletes. Twenty-two multi-sport athletes of mixed ability were exposed to either a normobaric hypoxic gas (intermittent hypoxic training group) or a placebo gas containing normal room air (placebo group). The participants breathed the gas mixtures in 5-min intervals interspersed with 5-min recovery periods of normal room air for a total of 90 min per day, 5 days per week, over a 3-week period. The oxygen in the hypoxic gas decreased from 13% in week 1 to 10% by week 3. The training and placebo groups underwent a total of four performance tests, including a familiarization and baseline trial before the intervention, followed by trials at 2 and 17 days after the intervention. Time to complete the 3-km run decreased by 1.7%[95% confidence interval (CI) = -0.6 - 3.9%] 2 days after, and by 2.3% (CI = 0.25 - 4.4%) 17 days after, the last hypoxic episode in the training relative to the placebo group. Substantial changes in the training relative to the placebo group also included increased reticulocyte count 2 days (23.5%; CI =-1.9 to 44.9%) and 12 days (14.6%; CI = -7.1 to 36.4%) post-exposure. The effect of intermittent hypoxic training on 3-km performance found in this study is likely to be beneficial, which suggests non-elite multi-sport athletes should expect such training to enhance performance. 相似文献
249.
The purpose of this study was to compare measures of body size in two samples of youth baseball players with normative data from the United States National Center for Health Statistics (NCHS) growth charts. One sample of youth baseball players participated in a local little league. The second sample of youth baseball players were members of eight of the twelve teams participating in the 1995 Dixie Youth World Series. Normative data for the United States (NCHS) were used as comparative data. Two trained anthropometrists measured standing height, sitting height, lower limb height, upper limb length, arm girth, calf girth, tricep skinfold, and abdomen skinfold on all participants. In both samples, pitchers, short stops, and first basemen were a more highly skilled group and exhibited larger body size (greater standing height, sitting height, lower limb height, upper limb length) than children who played at other positions. The standing height of local little league players was similar to the median of reference data at ages 7, 8, and 9 years. The standing height and weight of skilled players in both samples approximated the 75th percentile for standing height and weight at ages 10, 11, 12, and 13 years. The results suggest that baseball players exhibit larger body size than the normal population at young ages. Body size may be an important criterion used by coaches to select and assign young players to certain positions. 相似文献
250.
Mixing methods has recently achieved respectability as an appropriate approach to research design, offering a variety of advantages (Tashakkori & Teddlie, 2003). The purpose of this paper is to outline and evaluate a mixed methods approach within the domain of coaches' decision making. Illustrated with data from a policy-capturing study on coaches' decisions about an injured gymnast's participation in competition, the approach involves the concurrent collection of quantitative and qualitative data and a three-phase process of data analysis. It is argued that (a) the method described can provide additional insights into the factors involved in coaches' decision making, beyond those provided via quantitative or qualitative methods alone, and (b) mixing methods holds promise for coaching research more generally. 相似文献