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991.
In this paper college admissions are based on test scores and students can exert two types of effort: real learning and exam preparation. The former improves skills but the latter is more effective in raising test scores. In this setting the students with the lowest skills are no longer the ones with the lowest aptitude, but instead are the ones closest to the borderline for college admission. Increased access to college leads to greater income inequality between college graduates and non-graduates. Overall, the ability to study for the test leads to higher expected test scores but lower skills. 相似文献
992.
Emma Kate Zadow Cecilia Marie Kitic Sam Shi Xuan Wu James William Fell Murray John Adams 《European Journal of Sport Science》2018,18(3):367-375
Exercise has been demonstrated to have considerable effects upon haemostasis, with activation dependent upon the duration and intensity of the exercise bout. In addition, markers of coagulation and fibrinolysis have been shown to possess circadian rhythms, peaking within the morning (0600–1200?h). Therefore, the time of day in which exercise is performed may influence the activation of the coagulation and fibrinolytic systems. This study aimed to examine coagulation and fibrinolytic responses to short-duration high-intensity exercise when completed at different times of the day. Fifteen male cyclists (VO2max: 60.3?±?8.1?ml?kg?1?min?1) completed a 4-km cycling time trial (TT) on five separate occasions at 0830, 1130, 1430, 1730 and 2030. Venous blood samples were obtained pre- and immediately post-exercise, and analysed for tissue factor (TF), tissue factor pathway inhibitor (TFPI), thrombin–anti-thrombin complexes (TAT) and D-Dimer. Exercise significantly increased plasma concentrations of TF (p?.0005), TFPI (p?.0006), TAT complexes (p?.0012) and D-Dimer (p?.0003). There was a time-of-day effect in pre-exercise TF (p?=?.004) and TFPI (p?=?.031), with 0830 greater than 1730 (p .001), while 1730 was less than 2030?h (p?=?.008), respectively. There was no significant effect of time of day for TAT (p?=?.364) and D-Dimer (p?=?.228). Power output, TT time and heart rate were not significantly different between TTs (p?>?.05); however, percentage VO2max was greater at 1730 when compared to 2030 (p?=?.04). Due to a time-of-day effect present within TF, peaking at 0830, caution should be applied when prescribing short-duration high-intensity exercise bout within the morning in populations predisposed to hypercoagulability. 相似文献
993.
Shane Soboroff William Lovekamp Robert Jenkot 《Journal of Criminal Justice Education》2019,30(3):376-388
Research consistently shows that students and faculty are generally against expanding access to firearms on campus, and many stakeholders worry about the effects of campus carry laws on student violence, civility, and feelings of safety. We contribute to this literature by investigating how potential changes to campus carry policies affect students’ reported commitment to campus activities. Theories explaining fear of crime and social commitment led to hypotheses that predict members of socially disadvantaged groups—specifically women and minority students—would report less favorable attitudes toward gun possession on campus, greater feelings of vulnerability to victimization, and less commitment to the college environment when students or staff may possess guns. Hypotheses received support, and add to the growing literature documenting potential issues that legislators, administrators, and faculty might consider when debating the enactment of campus carry policies. 相似文献
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996.
Existing behavior-genetic research implicates substantial influence of heredity and modest influence of shared environment on reading achievement and reading disability. Applying DeFries-Fulker analysis to a combined sample of twins and adoptees (N = 4,886, including 266 reading-disabled probands), the present study replicates prior findings of considerable heritability for both reading achievement and reading disability. A simple biometric model adequately described parent and offspring data (combined N = 9,430 parents and offspring) across differing types of families present in the sample Analyses yielded a high heritability estimate (around 0.70) and a negligible shared-environmentality estimate for both reading achievement and reading disability. No evidence of gene × environment interaction was found for parental reading ability and parental educational attainment, the two moderators analyzed. 相似文献
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998.
William T. Howe Jr. Maria Shpeer 《Journal of Intercultural Communication Research》2019,48(3):203-220
This study examined the transition of veterans from the military to the classroom. Guided by communication accommodation theory (CAT), results of semi-structured interviews (N = 20) of military veterans were analyzed to see how and why participants described communication approaches in the university setting. Approaches appeared guided by inculcated values developed during earlier cultural experiences, in the military. Participants described interpersonal and group communication exchanges in three broad themes: cultural clash, perspective taking, and self-silencing. This research supports prior psychological research that explored difficulties combat veterans face after exit and extends this research to non-combat veterans from a communicative perspective. 相似文献
999.
Elizabeth P. Beggrow Minsu Ha Ross H. Nehm Dennis Pearl William J. Boone 《Journal of Science Education and Technology》2014,23(1):160-182
The landscape of science education is being transformed by the new Framework for Science Education (National Research Council, A framework for K-12 science education: practices, crosscutting concepts, and core ideas. The National Academies Press, Washington, DC, 2012), which emphasizes the centrality of scientific practices—such as explanation, argumentation, and communication—in science teaching, learning, and assessment. A major challenge facing the field of science education is developing assessment tools that are capable of validly and efficiently evaluating these practices. Our study examined the efficacy of a free, open-source machine-learning tool for evaluating the quality of students’ written explanations of the causes of evolutionary change relative to three other approaches: (1) human-scored written explanations, (2) a multiple-choice test, and (3) clinical oral interviews. A large sample of undergraduates (n = 104) exposed to varying amounts of evolution content completed all three assessments: a clinical oral interview, a written open-response assessment, and a multiple-choice test. Rasch analysis was used to compute linear person measures and linear item measures on a single logit scale. We found that the multiple-choice test displayed poor person and item fit (mean square outfit >1.3), while both oral interview measures and computer-generated written response measures exhibited acceptable fit (average mean square outfit for interview: person 0.97, item 0.97; computer: person 1.03, item 1.06). Multiple-choice test measures were more weakly associated with interview measures (r = 0.35) than the computer-scored explanation measures (r = 0.63). Overall, Rasch analysis indicated that computer-scored written explanation measures (1) have the strongest correspondence to oral interview measures; (2) are capable of capturing students’ normative scientific and naive ideas as accurately as human-scored explanations, and (3) more validly detect understanding than the multiple-choice assessment. These findings demonstrate the great potential of machine-learning tools for assessing key scientific practices highlighted in the new Framework for Science Education. 相似文献
1000.
Adriana J. Uma?a‐Taylor Stephen M. Quintana Richard M. Lee William E. Cross Jr. Deborah Rivas‐Drake Seth J. Schwartz Moin Syed Tiffany Yip Eleanor Seaton Ethnic Racial Identity in the st Century Study Group 《Child development》2014,85(1):21-39
Although ethnic and racial identity (ERI) are central to the normative development of youth of color, there have been few efforts to bring scholars together to discuss the theoretical complexities of these constructs and provide a synthesis of existing work. The Ethnic and Racial Identity in the 21st Century Study Group was assembled for this purpose. This article provides an overview of the interface of ERI with developmental and contextual issues across development, with an emphasis on adolescence and young adulthood. It proposes a metaconstruct to capture experiences that reflect both individuals’ ethnic background and their racialized experiences in a specific sociohistorical context. Finally, it presents milestones in the development of ERI across developmental periods. 相似文献