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691.
Reciprocal relations between sleep and adjustment were investigated. Participants included 246 adolescents (M = 15.80 years; 67.5% White, 32.5% Black/African American; 53% female, 47% male) at Time 1 (data collected 2012–2013), 227 at Time 2 (M = 16.78 years) and 215 at Time 3 (M = 17.70 years). Sleep–wake variables were measured with self-reports (sleepiness) and actigraphy (average sleep minutes and efficiency, variability in sleep minutes and efficiency). Adolescents reported on depression and anxiety symptoms, and parents reported on externalizing problems. Greater variability in sleep duration and efficiency as well as sleepiness predicted adjustment problems (range of R2: 36%–60%). Reciprocal relations were supported mostly for sleepiness (range of R2: 16%–32%). Results help understand bidirectional relations between sleep and adjustment.  相似文献   
692.
We investigate adolescent risk factors, measured at both early and late adolescence, for involvement in child maltreatment during adulthood. Comprehensive assessments of risk factors for maltreatment that use representative samples with longitudinal data are scarce and can inform multilevel prevention. We use data from the Rochester Youth Development Study, a longitudinal study begun in 1988 with a sample of 1,000 seventh and eighth graders. Participants have been interviewed 14 times and, at the last assessment (age 31), 80% were retained. Risk factors represent 10 developmental domains: area characteristics, family background/structure, parent stressors, exposure to family violence, parent–child relationships, education, peer relationships, adolescent stressors, antisocial behaviors, and precocious transitions to adulthood. Maltreatment is measured by substantiated reports from Child Protective Services records. Many individual risk factors (20 at early adolescence and 14 at later adolescence) are significantly, albeit moderately, predictive of maltreatment. Several developmental domains stand out, including family background/structure, education, antisocial behaviors, and precocious transitions. In addition, there is a pronounced impact of cumulative risk on the likelihood of maltreatment. For example, only 3% of the youth with no risk domains in their background at early adolescence were involved in later maltreatment, but for those with risk in 9 developmental domains the rate was 45%. Prevention programs targeting youth at high risk for engaging in maltreatment should begin during early adolescence when risk factors are already at play. These programs need to be comprehensive, capable of addressing the multiple and interwoven nature of risk that is associated with maltreatment.  相似文献   
693.
This synopsis centers on Eleanor Duckworth’s ideas about the relationship between education and intellectual development. Specifically, Duckworth described the essence of intellectual development as the “having of wonderful ideas” and the essence of pedagogy as the creation of occasions to “have wonderful ideas.” As opposed to accepting the persistent, pernicious educational belief that there is a single, best way to understand and a single, best way of explaining this understanding, Duckworth determined that all children can come to comparable, equally satisfactory, wonderful understandings when provided occasions to do so.  相似文献   
694.
This is the 9th in a series of articles exploring international trends in health science librarianship. The previous article in this series looked at Northern Ireland and the Republic of Ireland. In this issue the focus is Scotland and Wales. There will be three or four more articles this year tracking trends in the Far East, Africa, South Asia and the Middle East. JM  相似文献   
695.
Abstract

The aim of the present study was to examine the effects of movement intensity and path linearity on global positioning system (GPS) distance validity and reliability. One participant wore eight 1-Hz GPS receivers while walking, jogging, running, and sprinting over linear and non-linear 200-m courses. Five trials were performed at each intensity of movement on each 200-m course. One receiver was excluded from analysis due to errors during data collection. The results from seven GPS receivers showed the mean (±s) and percent bias of the GPS distance values on the 200-m linear course were 205.8 ± 2.4 m (2.8%), 201.8 ± 2.8 m (0.8%), 203.1 ± 2.2 m (1.5%), and 205.2 ± 4 m (2.5%) for the walk, jog, run, and sprint trial respectively. Walk and sprint distances were significantly different from jogging and running distances (P < 0.05). The GPS distance values on the 200-m non-linear course were 198.9 ± 3.5 m (?0.5%), 188.3 ± 2 m (?5.8%), 184.6 ± 2.9 m (?7.7%), and 180.4 ± 5.7 m (?9.8%) for the walk, jog, run, and sprint trial respectively; these were significantly lower than those for the corresponding values on the linear course (P < 0.05). Differences between all non-linear movement intensities were significant (P < 0.05). The overall coefficient of variation within and between receivers was 2.6% and 2.8% respectively. Path linearity and movement intensity appear to affect GPS distance accuracy via inherent positioning errors, update rate, and conditions of use; reliability decreases with movement intensity.  相似文献   
696.
Abstract

The purpose of this investigation was to quantify the body composition of speed skaters who were candidates for the 1980 United States Olympic Team. Subjects were 19 males between 16 and 27 years of age. Most subjects had just completed three months of intensive dry-land training. Seven skinfold fat, 11 circumference, and seven diameter sites were measured. Body density was determined by underwater weighing. Study of the speed skaters (mean ± standard deviation) gave the following results: height, 176 ± 8 cm; body weight, 69.6 ± 7.0 kg; body density, 1.081 ± 0.006 g/ml; and relative fat, 7.6 ± 2.6%. The eight speed skaters who were selected for the Olympic Team were significantly older, taller, and heavier in total body weight and fat free weight (FFW) than the non-Olympians. Thus, years of training and greater FFW may help differentiate international caliber male speed skaters. Data on Olympic speed skating candidates from 1968 showed them to be of similar age (20.1 yr) and height (176 cm), but greater in body weight (73.9 kg). Relative fat was not determined but the body mass index (Wt/ht2) showed that the present speed skaters may be leaner (24.0 vs 22.2). These differences in body composition were thought to be, in part, a result of the more rigorous training program currently used by speed skaters. The body composition of the speed skaters was also compared to that of other athletic groups.  相似文献   
697.
698.
International students, who are also often from non-English language speaking backgrounds (NESB students), are an important source of revenue for Australian universities. Yet little large-scale evidence exists about their performance once they arrive. Do these students perform worse than other students in Australian undergraduate classrooms? What happens to other students’ performance when these students are added to classrooms? I provide new empirical evidence on these questions using recent administrative panel data from the business schools of two Australian Technology Network universities. Results show strong and highly statistically significant main effects and spillover effects, raising concerns about the integration of international NESB students into the Australian tertiary environment.  相似文献   
699.
The extent to which peer influences on substance use in adolescence systematically vary in strength based on qualities of the adolescent and his or her close friend was assessed in a study of 157 adolescents (age: M = 13.35, SD = 0.64), their close friends, and their parents assessed longitudinally with a combination of observational, analogue, sociometric, and self-report measures from early to mid adolescence. The degree to which adolescents changed their levels of substance use in accord with their peers' baseline levels of use was predicted by a range of theoretically salient factors including: observed teen lack of autonomy and social support in prior interactions with mothers, low teen refusal skills, and the level of social acceptance of their close friend. Findings suggest the importance of both internal factors (e.g., autonomy and relatedness struggles) and external factors (e.g., social status of friends) in explaining why vulnerability to peer influence processes may be much greater for some adolescents than others.  相似文献   
700.
Research in Science Education - There is growing evidence that science capital (science-related forms of social and cultural capital) and family habitus (dispositions for science) influence STEM...  相似文献   
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