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   119266篇
  免费   1890篇
  国内免费   234篇
教育   81981篇
科学研究   13429篇
各国文化   2004篇
体育   9679篇
综合类   172篇
文化理论   1064篇
信息传播   13061篇
  2021年   938篇
  2020年   1677篇
  2019年   2605篇
  2018年   3188篇
  2017年   3452篇
  2016年   3461篇
  2015年   2332篇
  2014年   3202篇
  2013年   27340篇
  2012年   2456篇
  2011年   2854篇
  2010年   2366篇
  2009年   2625篇
  2008年   2446篇
  2007年   2192篇
  2006年   2405篇
  2005年   2391篇
  2004年   3076篇
  2003年   2307篇
  2002年   2104篇
  2001年   2025篇
  2000年   1573篇
  1999年   1445篇
  1998年   1279篇
  1997年   1349篇
  1996年   1547篇
  1995年   1360篇
  1994年   1340篇
  1993年   1338篇
  1992年   1407篇
  1991年   1310篇
  1990年   1324篇
  1989年   1239篇
  1988年   1088篇
  1987年   1037篇
  1986年   1046篇
  1985年   1297篇
  1984年   1182篇
  1983年   1089篇
  1982年   1085篇
  1981年   1014篇
  1980年   968篇
  1979年   1101篇
  1978年   1052篇
  1977年   962篇
  1976年   872篇
  1975年   710篇
  1974年   715篇
  1973年   683篇
  1972年   520篇
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
11.
National assessments suggest that many students do not display proficiency with fractions. Considering that time and materials are precious resources, many educators are looking to use technology to provide supplemental instruction with low demand on the instructor. The current study utilized a multiple-baseline design to examine the effects of the Motion Math: Bounce application on the fraction quantity comparison and number line placement skills of three fifth-grade students. Results indicate that Motion Math: Bounce improved the quantity comparison skills of all three participants and the number line skills of one participant. Additionally, all three participants made improvements from pre- to posttest on a measure of general fraction knowledge. Implications for future research and intervention implementation are discussed.  相似文献   
12.
Professor Gordon argues for a significant reorientation in the focus and impact of assessment in education. For the types of assessment activities that he advocates to prosper and positively impact education, serious attention must be paid to two important topics: (1) the conceptual underpinnings of the assessment practices we develop and use to support learning and instruction, and (2) the arguments and evidence we establish for their validity given the intended interpretive use. Such a focus highlights fundamental concepts that have long existed in the broader assessment literature – carefully defining and operationalizing our constructs and then validating the assessments of those constructs. What differs now are the conceptual frameworks, briefly outlined here, that can and must be used to guide both aspects of such work.  相似文献   
13.
This study investigated the effect of including explicit nature of science (NOS) content in read-alouds of elementary science trade books on the teaching and learning of NOS. We focused on three aspects of NOS: the creative, the empirical, and the inferential NOS. The trade books were read aloud by teachers in three hierarchical levels: Level I served as a control and consisted of a trade book that remained unmodified, Level II consisted of a trade book that had been modified to include explicit references to NOS, and Level III consisted of a modified trade book accompanied by educative curriculum materials that were aimed at improving the teachers' views of NOS as well as supporting teaching about NOS. We used the Views of Nature of Science Questionnaire-form CE (VNOS-CE) preintervention and postintervention to determine changes in teachers' views of NOS and interviews preintervention and postintervention to determine changes in students' views. Audio recordings of read-alouds were used to determine changes in teaching practice, including the frequency and the quality (i.e., naïve or informed) of the NOS references in the discussions. Interviews were used to determine teachers' perceptions of the modified trade books and educative curriculum materials. We found that both teachers and students developed more informed views of the targeted NOS aspects after the intervention and that teachers addressed NOS more often, and in a more informed manner, when they had trade books that explicitly supported NOS instruction and educative curriculum materials that supported their learning about NOS. Furthermore, they perceived the intervention materials favorably. Teachers' views and practices were able to change in tandem because of the intervention materials that supported explicit NOS instruction. We highlight the need for more widespread development of similar educative curriculum materials.  相似文献   
14.
ABSTRACT

The speed performance is involved not only in linear sprints, but also in a wide spectrum of multi-directional movements, such as curve sprinting. Curved sprint can be defined as sprint with gradual and continuous change of direction (COD). Although ~85% of the actions performed at maximum velocity in a professional soccer league are curvilinear sprints, there is not any specific test to assess this ability. This study aimed to analyse the reliability of a new curve sprint test, and compare its results with those obtained by soccer players in linear sprint. Forty experienced soccer players performed 3 attempts of curve sprint (using the penalty arc) to right and left side (17 m), and 3 linear sprints (17 m) in two different days. The ICCs (inter-session reliability) were 0.93 for sprint curve right side (CSRS) and 0.89 for sprint curve left side (CSLS), considered “acceptable”. The CVs (intra-session reliability) were 0.87% in CSRS and 1.15% in CSLS. The coefficient of determination (R2) between linear and curve sprinting was ~35%. The association between curve sides was “very large” (r = 0.878; p < 0.01). In summary, we showed that “curve sprint test” is highly reliable, and that curvilinear and linear sprints are different and independent actions.  相似文献   
15.
Children are capable of viewing object ownership as categorical and exclusive, but ownership claims can also vary by degree. This study investigated how children use these different conceptions of ownership in a giving and a taking task. In two studies, 4- to 7-year olds (= 105) could give and take craft objects that they or another child had found (weaker claim) and made (stronger claim). In Study 1, no additional ownership information was given, and in Study 2 categorical ownership was stated (“these belong to you”). The results showed that children used categorical ownership for their own objects but used ownership strength for the other child's objects, taking more of the found items.  相似文献   
16.
This study examined two possible mechanisms, evocative gene–environment correlation and prenatal factors, in accounting for child effects on parental negativity. Participants included 561 children adopted at birth, and their adoptive parents and birth parents within a prospective longitudinal adoption study. Findings indicated child effects on parental negativity, such that toddlers’ negative reactivity at 18 months was positively associated with adoptive parents’ over-reactive and hostile parenting at 27 months. Furthermore, we found that child effects on parental negativity were partially due to heritable (e.g., birth mother [BM] internalizing problems and substance use) and prenatal factors (e.g., BM illicit drug use during pregnancy) that influence children’s negative reactivity at 18 months. This study provides critical evidence for “child on parent” effects.  相似文献   
17.
This study identified social network profiles among children, determined whether profiles vary across sociodemographic characteristics, and investigated links between childhood profiles and depressive symptomology using three waves of data spanning 23 years (Wave 1, 1992 Metro-Detroit representative sample: n = 193, ages 8–12). Latent profile analysis revealed three profiles: Close Family (22%), Varied Family (57%), Friend and Family (21%). White children were more likely than Black children to be in the Friend and Family profile. Children in the Close Family profile reported the lowest levels of depressive symptomology in childhood, but exhibited the steepest increase over time. Findings suggest that close, family centric networks are protective in childhood, but less so as children develop into adulthood, highlighting the importance of considering developmental perspectives.  相似文献   
18.
Evidence of the internal consistency of standard-setting judgments is a critical part of the validity argument for tests used to make classification decisions. The bookmark standard-setting procedure is a popular approach to establishing performance standards, but there is relatively little research that reflects on the internal consistency of the resulting judgments. This article presents the results of an experiment in which content experts were randomly assigned to one of two response probability conditions: .67 and .80. If the standard-setting judgments collected with the bookmark procedure are internally consistent, both conditions should produce highly similar cut scores. The results showed substantially different cut scores for the two conditions; this calls into question whether content experts can produce the type of internally consistent judgments that are required using the bookmark procedure.  相似文献   
19.
Grit has been defined as passionate perseverance toward long-term challenging goals and it is associated with various positive outcomes for youth, including academic achievement. However, less is known about these associations for the two facets of grit (i.e., perseverance of effort, consistency of interest) and few studies have examined the link between grit and perceived social support. The present study examined the group-level demographic differences (i.e., gender, grade, socioeconomic status, and special education status) of grit in a high school sample (N = 1,077). In addition, direct associations between grit and perceived social support from multiple sources (i.e., teacher, classmate, parent) were examined, as well as a potential enhancing effect of social support as a moderator of the relation between grit and academic achievement. Results indicated positive associations among grit and its facets with social support from parents and classmates. Furthermore, the positive relation between grit and achievement was stronger for students reporting high social support from teachers, but not other sources (i.e., classmates, parents). Practical and theoretical implications for promoting student success are discussed.  相似文献   
20.
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