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51.
Abstract This study was designed to determine whether illness during the academic year, when gender and academic readiness are controlled, is the variable accounting for the demonstrated relationship between life change index and subsequent academic performance. A weak though significant inverse association was found between life change and grades: this association persisted even after statistical adjustment for gender, academic readiness, and illness experience. There was no evidence that illness experience mediated the life change-performance relationship. The association was not subject to a threshold effect according to level of life change. 相似文献
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Kindergarten has become increasingly academic in nature. One of the primary dilemmas arising from this shift is the tension between the use of developmentally appropriate practices and the obligation to teach academic standards. To gain a deeper understanding of how kindergarten is enacted in the evolving curricular landscape, we look beyond these competing perspectives to develop a theoretical framework informed by Schwab's conception of the eclectic and the four commonplaces. We re-envision the four commonplaces – subject matter, teacher, milieu, and learner – to align them with contemporary conceptions of educational purposes, practical theory, classroom climate, and childhood. Acknowledging that kindergarten is an eclectic space, we create a robust theoretical framework for researchers interested in classroom research. The application of this framework is explored using an ethnographic methodology that integrates data from classroom observations, teacher interviews, and photo elicitation interviews with the students in one kindergarten classroom. 相似文献
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《Journal of the American College of Radiology》2018,15(10):1500-1504
As academic radiology practices expand into the community, the lines that have historically distinguished the academic from private practice radiologist are becoming increasingly blurred. In this article, we introduce the new concept of the community-based academic radiologist and address some of the unique challenges and opportunities faced by these radiologists navigating this new hybrid role of academician and radiologist in community-based private practice. 相似文献
58.
《Pharmaceutical development and technology》2013,18(4):466-476
A novel flavonoid-polysaccharide conjugate was synthesized by free radical grafting of quercetin on starch. The covalent insertion of quercetin in the polymeric chain was confirmed by FT-IR, DSC and fluorescence analyses, while an estimation of the amount of quercetin bound per g of polymer was obtained by the Folin-Ciocalteu assay. The conjugate shows improved UV stability and retains the antioxidant properties of free quercetin, such as scavenging activity towards free radicals (DPPH and peroxynitrite); inhibition of the free radical formation (peroxidation of linoleic acid) and total antioxidant activity. The conjugate also prevented drug degradation and shows potential health functionality in the treatment of Alzheimer disease, diabetes and as skin-whitening agent. 相似文献
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《Drug metabolism reviews》2012,44(4):533-544
AbstractDevelopment of effective and cost-efficient bone tissue engineering grafts has been the key area of research for regenerative medicine, yet an ideal grafting material has remained elusive due in large part to the highly dynamic nature of bone. A wide array of materials, both natural and synthetic, have been implemented as potential candidates for commercially available products, yet the gold standard for grafting material still remains autogenous bone. We review currently commercially available bone graft materials and relevant graft characteristics that impact the effectiveness of tissue repair, emphasizing the advantages and disadvantages of materials based on composition and origin. Examined materials were selected through a web-based search for readily accessible and clinically applicable graft materials. Grafts were then categorized according to material source to examine advantages and disadvantages associated with allogenic, xenogeneic, synthetic materials. Lastly, the application of bioactive molecules onto these basal grafts is explored to illustrate the enhancement and regulative capacity of these additives on traditional osteobiologic materials. 相似文献
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《Scandinavian journal of medicine & science in sports》2018,28(1):228-236
The aim of this study was to investigate the influence of a school‐based intervention with a tripling of physical education (PE ) lessons from two (90 minutes) to six lessons per week (270 minutes) on scholastic performance. This study is part of the CHAMPS study‐DK , a quasi‐experimental study that began in 2008. The intervention group consisted of six schools, and the control group consisted of four matched schools (mean age at baseline=8.4 years, kindergarten class fourth grade). Academic performance was extracted from the national test system from 2010 to 2014 (Math and Danish were measured at third and sixth, and second, fourth and sixth grades, respectively). Participants included 1888 students participating in at least one scholastic performance test. Linear mixed models were applied to test for differences between groups and adjusted for known confounders. No significant differences were observed between groups in the academic performance tests (control group reference); Danish second grade β=−1.34 (95% CI −9.90, 7.22), fourth grade β=0.22 (95% CI −6.12, 6.56), sixth grade β=1.03 (95% CI −5.02, 7.08), and all grades combined β=0.28 (95% CI −5.74, 6.31) and Math third grade β=−2.87 (95% CI −9.65, 3.90), sixth grade β=0.99 (95% CI −7.36, 9.34) and combined β=−1.20 (95% CI −8.10, 5.71). In conclusion, no significant differences were observed between intervention and control schools for scholastic performance. Importantly, there were no negative effects of additional PE on scholastic outcomes, despite more PE and longer school days for intervention children. 相似文献