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91.
Recent advances have enabled diagnostic classification models (DCMs) to accommodate longitudinal data. These longitudinal DCMs were developed to study how examinees change, or transition, between different attribute mastery statuses over time. This study examines using longitudinal DCMs as an approach to assessing growth and serves three purposes: (1) to define and evaluate two reliability measures to be used in the application of longitudinal DCMs; (2) through simulation, demonstrate that longitudinal DCM growth estimates have increased reliability compared to longitudinal item response theory models; and (3) through an empirical analysis, illustrate the practical and interpretive benefits of longitudinal DCMs. A discussion describes how longitudinal DCMs can be used as practical and reliable psychometric models when categorical and criterion‐referenced interpretations of growth are desired.  相似文献   
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Hale  Piers J. 《Metascience》2019,28(2):297-300
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Teachers participating in curricular reforms, especially reforms based on constructivism, are expected to bring about change in their teaching approach. This is often a difficult, complex and intensive process, and demands a radical reculturing of the classroom. This is also the case for social constructivist reforms in chemistry education, which are based on a context-based approach. Educational change is a social and interactional process, and during this change teachers will engage in negotiations with their students about the reform. These teacher–student negotiations have a profound impact on the succeeding of the reform. This study explores the teacher–student interactions during the reform that shape and alter the context-based chemistry approach. We focused on two teachers, of whom it was found in an earlier study that one of them succeeded in implementing the reform, while the other one struggled. By following them for one school year, in which in-depth qualitative data was collected through various instruments, we developed insights about the teacher–student negotiations that influenced the educational reform. Three themes emerged from the data: “agency of learning,” “vulnerability,” and “care.” The differences that were found between the teachers regarding these themes help explain why and how the reform can become a success and why the reform often fails to change classroom practice.  相似文献   
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This study examined the relationship between sit-to-stand (STS) power and physical function in adults with severe obesity. Thirty-eight adults (age: 44 ± 12 years; body mass index [BMI]: 45.2 ± 7.8 kg/m2) completed evaluations of STS power, strength and functional performance. STS power was measured with a wearable inertial sensor, strength was assessed with the isometric mid-thigh pull, and function was measured with the timed up-and-go (TUG), six-minute walk test (6MWT) and 30-s chair STS. Power and strength (normalised to body mass) entered regression models in addition to age, gender, BMI and physical activity (daily step count). Power displayed large univariate associations with TUG (r = 0.50) and 30-s chair STS (r = 0.67), and a moderate association with 6MWT (r = 0.49). Forward stepwise regression revealed that power independently contributed to TUG (β = ?0.40, p = 0.010), 30-s chair STS (β = 0.67, p < 0.001) and 6MWT performance (β = 0.27, p = 0.007). Power also appeared to be a superior determinant of function compared with strength. Power generated via the STS transfer largely underpins the ability to perform functional tasks in adults with severe obesity, although intervention studies are required to investigate a potentially causal relationship.  相似文献   
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Colleges and universities in the United States often promote diversity through a neoliberal lens by framing diversity as a celebration of individual differences or a commodity that students can gain by attending their institution. In communication courses, diversity has been conceptualized through both neoliberal and critical lenses, but limited research has investigated how communication students define and explain diversity. The focus of this study was to understand how communication students define diversity. We performed thematic analyses on open-ended survey responses to investigate how communication students define diversity. Four themes emerged from our analyses: (a) diversity is a mechanism for unifying communities, (b) diversity is an affirmation of individual differences, (c) diversity is a harbinger of acceptance and equality, and (d) diversity is a disruptive force that re-centers the voices of traditionally marginalized people. Our findings indicate most communication students define diversity through a neoliberal lens. However, 3% of our participants conceptualized diversity through a critical lens by explaining that diversity should create space for those who are marginalized to have their voices heard. We conclude by providing recommendations for communication instructors to incorporate more critical conversations about diversity into their classrooms and foster diverging discourses about diversity across communication curricula.  相似文献   
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Administrators of color in predominantly White institutions (PWI) navigate from dual positions of privilege and marginalization. Within PWIs, administrators of color experience marginalization in terms of their racial/ethnic makeup. Specifically focusing on the administrative level, 95.8% of executive provosts and 86.2% of deans of academic colleges are White. At the faculty level, nearly 10% of full professors are people of color. However, even with such exclusionary practices, 87.7% of chief diversity officers are racial minorities. The current study seeks to understand how highly educated administrators of color work for diversity, inclusion, and equity initiatives while navigating from their dual positions of marginalization and privilege. Using the theoretical lenses of co-cultural theory, dominant group theory, and intersectionality, the study seeks to understand how privilege and marginalization ebbs and flows depending on particular contexts. Findings indicate that optimizing privilege through co-cultural praxis and impeding through mentoring are two common strategies used by administrators of color.  相似文献   
100.
This investigation assessed the effect of dietary nitrate (NO3?) supplementation, in the form of beetroot juice (BR), on repeat-sprint performance in normoxia and normobaric hypoxia. 12 male team-sport athletes (age 22.3 ± 2.6 y, VO2peak 53.1 ± 8.7 mL.kg?1.min?1) completed three exercise trials involving a 10 min submaximal warm-up and 4 sets of cycling repeat-sprint efforts (RSE; 9 × 4 s) at sea level (CON), or at 3000 m simulated altitude following acute supplementation (140 mL) with BR (HYPBR; 13 mmol NO3?) or NO3depleted BR placebo (HYPPLA). Peak (PPO) and mean (MPO) power output, plus work decrement were recorded during the RSE task, while oxygen consumption (VO2) was measured during the warm-up. There were no significant differences observed between HYPBR and HYPPLA for PPO or MPO; however, work decrement was reduced in the first RSE set in HYPBR compared with HYPPLA. There was a moderate effect for VO2 to be lower following BR at the end of the 10 min warm-up (ES = 0.50 ± 0.51). Dietary NO3? may not improve repeat-sprint performance in hypoxia but may reduce VO2 during submaximal exercise. Therefore, BR supplementation may be more effective for performance improvement during predominantly aerobic exercise.  相似文献   
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