首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   811篇
  免费   15篇
  国内免费   2篇
教育   602篇
科学研究   40篇
各国文化   10篇
体育   89篇
综合类   3篇
文化理论   8篇
信息传播   76篇
  2023年   2篇
  2022年   5篇
  2021年   17篇
  2020年   15篇
  2019年   33篇
  2018年   41篇
  2017年   54篇
  2016年   38篇
  2015年   29篇
  2014年   31篇
  2013年   144篇
  2012年   19篇
  2011年   23篇
  2010年   25篇
  2009年   19篇
  2008年   21篇
  2007年   22篇
  2006年   19篇
  2005年   15篇
  2004年   23篇
  2003年   23篇
  2002年   21篇
  2001年   11篇
  2000年   14篇
  1999年   12篇
  1998年   7篇
  1997年   11篇
  1996年   10篇
  1995年   8篇
  1994年   9篇
  1993年   11篇
  1992年   11篇
  1991年   4篇
  1990年   6篇
  1989年   4篇
  1988年   8篇
  1987年   10篇
  1986年   3篇
  1985年   5篇
  1984年   4篇
  1983年   5篇
  1980年   7篇
  1979年   4篇
  1977年   2篇
  1976年   3篇
  1975年   2篇
  1974年   2篇
  1906年   1篇
  1843年   1篇
  1830年   1篇
排序方式: 共有828条查询结果,搜索用时 296 毫秒
91.
In typical development, gestures precede and predict language development. This study examines the developmental sequence of expressive communication and relations between specific gestural and language milestones in toddlers with autism spectrum disorder (ASD), who demonstrate marked difficulty with gesture production and language. Communication skills across five stages (gestures, word approximations, first words, gesture-word combinations, and two-word combinations) were assessed monthly by blind raters for toddlers with ASD participating in an randomized control trial of parent-mediated treatment (N = 42, 12–30 months). Findings revealed that toddlers acquired skills following a reliable (vs. idiosyncratic) sequence and the majority of toddlers combined gestures with words before combining words in speech, but in contrast to the pattern observed in typical development, a significant subset acquired pointing after first words.  相似文献   
92.
93.
Empathy is the combined ability to interpret the emotional states of others and experience resultant, related emotions. The relation between prefrontal electroencephalographic asymmetry and emotion in children is well known. The association between positive emotion (assessed via parent report), empathy (measured via observation), and second-by-second brain electrical activity (recorded during a pleasurable task) was investigated using a sample of one hundred twenty-eight 6- to 10-year-old children. Contentment related to increasing left frontopolar activation ( p  < .05). Empathic concern and positive empathy related to increasing right frontopolar activation ( p s < .05). A second form of positive empathy related to increasing left dorsolateral activation ( p  < .05). This suggests that positive affect and (negative and positive) empathy both relate to changes in prefrontal activity during a pleasurable task.  相似文献   
94.
This study examined childhood antecedents and developmental outcomes associated with trajectories of mild and harsh parental physical discipline. Interview, questionnaire, and observational data were available from 499 children followed from ages 5 to 16 and from 258 children in an independent sample followed from ages 5 to 15. Analyses indicated distinct physical discipline trajectory groups that varied in frequency of physical discipline and rate of change. In both samples, family ecological disadvantage differentiated the trajectory groups; in the first sample, early child externalizing also differentiated the groups. Controlling for early childhood externalizing, the minimal/ceasing trajectory groups were associated with the lowest levels of subsequent adolescent antisocial behavior in both samples and with parent–adolescent positive relationship quality in the second sample.  相似文献   
95.
96.
Biology of the twenty-first century is an increasingly quantitative science. Undergraduate biology education therefore needs to provide opportunities for students to develop fluency in the tools and language of quantitative disciplines. Quantitative literacy (QL) is important for future scientists as well as for citizens, who need to interpret numeric information and data-based claims regarding nearly every aspect of daily life. To address the need for QL in biology education, we incorporated quantitative concepts throughout a semester-long introductory biology course at a large research university. Early in the course, we assessed the quantitative skills that students bring to the introductory biology classroom and found that students had difficulties in performing simple calculations, representing data graphically, and articulating data-driven arguments. In response to students'' learning needs, we infused the course with quantitative concepts aligned with the existing course content and learning objectives. The effectiveness of this approach is demonstrated by significant improvement in the quality of students'' graphical representations of biological data. Infusing QL in introductory biology presents challenges. Our study, however, supports the conclusion that it is feasible in the context of an existing course, consistent with the goals of college biology education, and promotes students'' development of important quantitative skills.  相似文献   
97.
Using data from three waves of longitudinal surveys of the 2001 freshman cohort of the Gates Millennium Scholars (GMS) program, this study examined linkages between student engagement in college activities and early career earnings in the labor market. The results indicated that social engagement was positively related to early career earnings of college graduates while academic engagement was not. When considering students who majored in STEM fields versus those in non-STEM fields, results showed academic engagement to be positively related to early career earnings for non-STEM students but slightly negatively related to earnings in the labor market for STEM students. Social engagement was positive for graduates in the STEM fields but not significant for non-STEM students. Altogether, results show a complex relationship between student engagement and early career earnings. Implications for research and institutional policy are discussed.  相似文献   
98.
The purpose of this investigation was to examine the validity of energy expenditure (EE), steps, and heart rate measured with the Apple Watch 1 and Fitbit Charge HR. Thirty-nine healthy adults wore the two monitors while completing a semi-structured activity protocol consisting of 20 minutes of sedentary activity, 25 minutes of aerobic exercise, and 25 minutes of light intensity physical activity. Criterion measures were obtained from an Oxycon Mobile for EE, a pedometer for steps, and a Polar heart rate strap worn on the chest for heart rate. For estimating whole-trial EE, the mean absolute percent error (MAPE) from Fitbit Charge HR (32.9%) was more than twice that of Apple Watch 1 (15.2%). This trend was consistent for the individual conditions. Both monitors accurately assessed steps during aerobic activity (MAPEApple: 6.2%; MAPEFitbit: 9.4%) but overestimated steps in light physical activity. For heart rate, Fitbit Charge HR produced its smallest MAPE in sedentary behaviors (7.2%), followed by aerobic exercise (8.4%), and light activity (10.1%). The Apple Watch 1 had stronger validity than the Fitbit Charge HR for assessing overall EE and steps during aerobic exercise. The Fitbit Charge HR provided heart rate estimates that were statistically equivalent to Polar monitor.  相似文献   
99.
This study aimed to examine the reliability of different power and velocity variables during the Smith machine bench press (BP) and bench press throw (BPT) exercises. Twenty-two healthy men conducted four testing sessions after a preliminary BP one-repetition maximum (1RM) test. In a counterbalanced order, participants performed two sessions of BP in one week and two sessions of BPT in another week. Mean propulsive power, peak power, mean propulsive velocity, and peak velocity at each tenth percentile (20–70% of 1RM) were recorded by a linear transducer. The within-participants coefficient of variation (CV) was higher for the load–power relationship compared to the load–velocity relationship in both the BP (5.3% vs. 4.1%; CV ratio = 1.29) and BPT (4.7% vs. 3.4%; CV ratio = 1.38). Mean propulsive variables showed lower reliability than peak variables in both the BP (5.4% vs. 4.0%, CV ratio = 1.35) and BPT (4.8% vs. 3.3%, CV ratio = 1.45). All variables were deemed reliable, with the peak velocity demonstrating the lowest within-participants CV. Based upon these findings, the peak velocity should be chosen for the accurate assessment of BP and BPT performance.  相似文献   
100.
This investigation examined the effect of beetroot juice (BR) supplementation, a source of dietary nitrate (NO3?), on cycling time-trial (TT) performance and thermoregulation in the heat. In a double-blind, repeated-measures design, 12 male cyclists (age 26.6 ± 4.4 years, VO2peak 65.8 ± 5.5 mL.kg?1.min?1) completed four cycling TTs (14 kJ.kg?1) in hot (35°C, 48% relative humidity) and euthermic (21°C, 52%) conditions, following 3 days supplementation with BR (6.5 mmol NO3? for 2 days and 13 mmol NO3? on the final day), or NO3depleted placebo (PLA). Salivary NO3? and nitrite, core (Tc) and mean skin temperature (Tsk) were measured. Salivary NO3? and nitrite increased significantly post-BR supplementation (< 0.001). Average TT completion time (mm:ss) in hot conditions was 56:50 ± 05:08 with BR, compared with 58:30 ± 04:48 with PLA (= 0.178). In euthermic conditions, average completion time was 53:09 ± 04:35 with BR, compared with 54:01 ± 04:05 with PLA (= 0.380). The TT performance decreased (< 0.001), and Tc (< 0.001) and Tsk (< 0.001) were higher in hot compared with euthermic conditions. In summary, BR supplementation has no significant effect on cycling TT performance in the heat.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号