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   13473篇
  免费   177篇
  国内免费   21篇
教育   9391篇
科学研究   1524篇
各国文化   125篇
体育   1149篇
综合类   6篇
文化理论   98篇
信息传播   1378篇
  2021年   139篇
  2020年   195篇
  2019年   268篇
  2018年   368篇
  2017年   351篇
  2016年   357篇
  2015年   238篇
  2014年   315篇
  2013年   2317篇
  2012年   294篇
  2011年   319篇
  2010年   279篇
  2009年   218篇
  2008年   267篇
  2007年   238篇
  2006年   232篇
  2005年   208篇
  2004年   229篇
  2003年   207篇
  2002年   175篇
  2001年   446篇
  2000年   292篇
  1999年   253篇
  1998年   118篇
  1997年   155篇
  1996年   132篇
  1995年   123篇
  1994年   144篇
  1993年   110篇
  1992年   181篇
  1991年   191篇
  1990年   194篇
  1989年   200篇
  1988年   165篇
  1987年   159篇
  1986年   168篇
  1985年   206篇
  1984年   161篇
  1983年   151篇
  1982年   128篇
  1981年   122篇
  1980年   116篇
  1979年   163篇
  1978年   131篇
  1977年   117篇
  1976年   92篇
  1975年   112篇
  1974年   100篇
  1973年   107篇
  1971年   98篇
排序方式: 共有10000条查询结果,搜索用时 12 毫秒
141.
ABSTRACT

The objective of this study was to analyse the effect of the use of social networks in smartphones or playing video games on the passing decision-making performance in professional soccer athletes. Participants were 25 male professional soccer athletes (mean ± SD: age 23.4 ± 2.8 years). The participants performed three randomised conditions divided into three groups: control (CON), smartphone (SMA), and video game (VID). Before and after each experimental condition, the Stroop Task assessed the level of induced mental fatigue. Then, the athletes performed a simulated soccer match. A CANON® camera recorded the matches for further analysis on passing decision-making performance. A group effect was identified (< .01) with impairment on passing decision-making performance for the SMA (p = .01, ES = 0.5) and VID (p = .01, ES = 0.5) conditions. We concluded that the use of social networks on smartphones and/or playing video games right before official soccer matches might impair the passing decision-making performance in professional soccer athletes.  相似文献   
142.
Though there is a long tradition of band members quitting the group or taking a hiatus, the rock group as an organization to produce music continues to be both popular and economically viable. The research question addressed in this paper is whether or not it is a good idea to quit or take a hiatus from the group. We begin with a discussion of the framework for understanding why groups are formed and why they may be difficult to keep together. We then discuss differences between groups in the decade of the 1960s versus today. We argue that there is something unique about the output of the group even with the changes in the structure of contracts, compensation, and consumer focus on the artist that explain the resilience of the rock band as an organizational form within which to create music. We compare the charting success of bands that have members leave the group with the charting success of the members who left the group. We identified the groups in five representative years: 1965, 1975, 1985, 1995, and 2005. We then analyzed the entire Billboard Hot 100 charting careers of those groups and the artists who quit those groups. Our main finding is that when charting success is divided equally among members, going solo pays off—there is a clear economic rationale because solo acts have greater average charting success than the original bands they started in. The other ensuing side projects: duos, collaborations, and other groups are not as lucrative as the original bands. These findings are valid for members of charting groups from each of the 5 years examined. Despite the difficulties in keeping a rock band together, there are fewer band breakups today and remaining with the group generally results in a longer and more productive charting career. Thus, the rock group remains an important organization for producing contemporary music. However, there remains a compelling incentive to go solo. Superstars may benefit from solo projects, but for the average, non-superstar group member, in many circumstances it is better for the band to stay together if the income is divided equally.  相似文献   
143.
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   
144.
This study presents a worked example of a stepped process to reliably estimate the habitual physical activity and sedentary time of a sample of young children. A total of 299 children (2.9 ± 0.6 years) were recruited. Outcome variables were daily minutes of total physical activity, sedentary time, moderate to vigorous physical activity and proportional values of each variable. In total, 282 (94%) provided 3 h of accelerometer data on ≥1 day and were included in a 6-step process: Step-1: determine minimum wear-time; Step-2: process 7-day-data; Step-3: determine the inclusion of a weekend day; Step-4: examine day-to-day variability; Step-5: calculate single day intraclass correlation (ICC) (2,1); Step-6: calculate number of days required to reach reliability. Following the process the results were, Step-1: 6 h was estimated as minimum wear-time of a standard day. Step-2: 98 (32%) children had ≥6 h wear on 7 days. Step-3: no differences were found between weekdays and weekend days (P ≥ 0.05). Step-4: no differences were found between day-to-day variability (P ≥ 0.05). Step-5: single day ICC’s (2,1) ranged from 0.48 (total physical activity and sedentary time) to 0.53 (proportion of moderate to vigorous physical activity). Step-6: to reach reliability (ICC = 0.7), 3 days were required for all outcomes. In conclusion following a 7 day wear protocol, ≥6 h on any 3 days was found to have acceptable reliability. The stepped-process offers researchers a method to derive sample-specific wear-time criterion.  相似文献   
145.
The development of a comprehensive protocol for quantifying soccer-specific skill could markedly improve both talent identification and development. Surprisingly, most protocols for talent identification in soccer still focus on the more generic athletic attributes of team sports, such as speed, strength, agility and endurance, rather than on a player’s technical skills. We used a multivariate methodology borrowed from evolutionary analyses of adaptation to develop our quantitative assessment of individual soccer-specific skill. We tested the performance of 40 individual academy-level players in eight different soccer-specific tasks across an age range of 13–18 years old. We first quantified the repeatability of each skill performance then explored the effects of age on soccer-specific skill, correlations between each of the pairs of skill tasks independent of age, and finally developed an individual metric of overall skill performance that could be easily used by coaches. All of our measured traits were highly repeatable when assessed over a short period and we found that an individual’s overall skill – as well as their performance in their best task – was strongly positively correlated with age. Most importantly, our study established a simple but comprehensive methodology for assessing skill performance in soccer players, thus allowing coaches to rapidly assess the relative abilities of their players, identify promising youths and work on eliminating skill deficits in players.  相似文献   
146.
Abstract

Motorsport is an under-researched area of socio-historical study. There is particularly limited academic understanding of female involvement in the social world of motorsports. Therefore, this paper focuses on the role of the media in presenting and establishing motorsport for women. In particular, a documentary analysis of articles published by a UK national newspaper group from 1890, and a case study of an all-female UK-based motor-racing championship are used to account for gendered processes that have influenced attitudes and behaviours towards women motor racers. The motor car emerged through technological progress in an overtly masculine-dominated industrial period. Traditional assumptions and biologically deterministic attitudes towards women were used by men to position motoring and motor-racing as a male preserve. Newspaper reporting throughout the 1930s suggests an era of heightened success for women motor racers as a result of gaining access to a key resource in the form of Brooklands motor-racing circuit. Following the Second World War, there was increasing commercialization and professionalization of male-dominated motorsport, as well as renewed marginalization and trivialization of female participants within the newspapers. These processes continue to influence perceptions of women in contemporary motorsport.  相似文献   
147.

Objective

The authors explored the feasibility and possible benefit of tablet-based educational materials for patients in clinic waiting areas.

Methods

We distributed eight tablets preloaded with diagnosis-relevant information in two clinic waiting areas. Patients were surveyed about satisfaction, usability, and effects on learning. Technical issues were resolved.

Results

Thirty-seven of forty patients completed the survey. On average, the patients were satisfied in all categories.

Conclusions

Placing tablet-based educational materials in clinic waiting areas is relatively easy to implement. Patients using tablets reported satisfaction across three domains: usability, education, and satisfaction.  相似文献   
148.
Borck  C. Ray 《The Urban Review》2020,52(2):376-391

Despite persistent class and race inequalities in educational attainment and achievement in the U.S., hegemonic cultural ideologies and urban education politics and policies continue to proceed from an insistence that education is the great equalizer. These ideologies do not take into account the ways that normative school culture and pedagogical praxes take for granted middle-class, white-supremacist cultural assumptions that privilege student populations whose social locations already probabilize high rates of achievement and attainment. Vast research published in The Urban Review and elsewhere has demonstrated the importance and efficacy of culturally sustaining pedagogy for improving outcomes for economically marginalized students of color (Allen in Urban Rev 47(1):209–231, 2015; Delpit in Harv Educ Rev 56(4):379–386, 1995; Farinde-Wu et al. in Urban Rev 49(2):279–299, 2017; Gay in culturally responsive teaching: theory, research, and practice, Teachers College Press, New York, 2010; Graves in Berkeley Rev Educ 5(1):5–32, 2014; Jemal in Urban Rev 49(4):602–626, 2017; Ladson-Billings in Crossing over to Canaan: the journey of new teachers in classrooms, Jossey-Bass, San Francisco, 2001, The dreamkeepers: successful teachers of African American children, Jossey-Bass Publishers, San Francisco, 2009; Lee in Culture, literacy and learning: taking bloom in the midst of the whirlwind, Teachers College Press, New York, 2006; Marciano in Urban Rev 49(1):169–187, 2016; Nieto in Language, culture, and teaching: critical perspectives, Routledge, New York, 2010; Paris in Educ Res 41(3):93–97, 2012; Paris and Alim in Culturally sustaining pedagogies: teaching and learning for justice in a changing world, Teachers College Press, New York, 2017; Wiggan and Watson in Urban Rev 48(5):766–798, 2016; Yosso in Race Ethn Edu, 8(1):69–91, 2005). This article uses rich ethnographic data from a transfer school in Brooklyn, New York that serves financially insecure youth of color who are “over-age and under-credited.” These data and my analysis showcase the expertise and indigenous knowledges of teachers who practice cultural relevance and critical racial awareness in order to engage, retain, graduate and prepare students who are historically and presently marked for failure by an education system that has always been more adept at reproducing social inequality than disrupting it (Borck in Qual Inq 20(10):1–8, 2016).

  相似文献   
149.
OBJECTIVE: To assess: (1) ethnic differences in the health-risk behaviors, mental health problems, and adverse parenting beliefs during pregnancy of low-income Mexican American and European American women; and, (2) the extent to which these risks varied with levels of acculturation among low-income Mexican American women. METHOD: Participants were 594 primiparous, low-income, urban women. A cross-sectional design was used to compare the 331 Mexican American women to the 263 European American. Language was used to assess the level of acculturation of the Mexican American women. Interviews were used to evaluate health-risk behaviors, mental health problems, and adverse parenting beliefs. RESULTS: In comparison to European American women, Mexican American women were at lower risk for cigarette smoking during pregnancy and higher risk for adverse parenting beliefs. Among Mexican American women, Spanish speakers were at lower risk for cigarette smoking and mental health problems during pregnancy, and higher risk for adverse parenting beliefs than bilingual and English speakers. CONCLUSIONS: The findings indicate that ethnic differences in cigarette smoking and parenting beliefs during pregnancy were concentrated on the less acculturated, low-income, and primarily unmarried Spanish speaking Mexican American women. Moreover, acculturation is differentially related to cigarette smoking and parenting beliefs. Therefore, acculturation needs to be considered in the development of preventive interventions in order to appropriately target the specific needs of different sub-populations of Mexican Americans.  相似文献   
150.
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