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排序方式: 共有1834条查询结果,搜索用时 15 毫秒
21.
Report of a workshop: waterborne non-A, non-B hepatitis 总被引:2,自引:0,他引:2
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Rubins Daniel J Meng Xiangjun McQuade Paul Klimas Michael Getty Krista Lin Shu-An Connolly Brett M. O’Malley Stacey S. Haley Hyking Purcell Mona Gantert Liza Holahan Marie Lindgren Joel Eklund Pär Ekblad Caroline Frejd Fredrik Y. Hostetler Eric D. González Trotter Dinko E. Evelhoch Jeffrey L. 《Molecular imaging and biology》2021,23(2):241-249
Molecular Imaging and Biology - In vivo imaging of programmed death ligand 1 (PD-L1) during immunotherapy could potentially monitor changing PD-L1 expression and PD-L1 expression heterogeneity... 相似文献
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Rarely a new research area has gotten such an overwhelming amount of attention as have microRNAs. Although several basic questions regarding their biological principles still remain to be answered, many specific characteristics of microRNAs in combination with compelling therapeutic efficacy data and a clear involvement in human disease have triggered the biotechnology community to start exploring the possibilities of viewing microRNAs as therapeutic entities. This review serves to provide some general insight into some of the current microRNAs targets, how one goes from the initial bench discovery to actually developing a therapeutically useful modality, and will briefly summarize the current patent landscape and the companies that have started to explore microRNAs as the next drug target. 相似文献
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The temporomandibular joint (TMJ) is a specialized synovial joint essential for the function of the mammalian jaw. The main components of the TMJ are the mandibular condyle, the glenoid fossa of the temporal bone, and a fibrocartilagenous disc interposed between them. The genetic program for the development of the TMJ remains poorly understood. Here we show the crucial role of sprouty (Spry) genes in TMJ development. Sprouty genes encode intracellular inhibitors of receptor tyrosine kinase (RTK) signaling pathways, including those triggered by fibroblast growth factors (Fgfs). Using in situ hybridization, we show that Spry1 and Spry2 are highly expressed in muscles attached to the TMJ, including the lateral pterygoid and temporalis muscles. The combined inactivation of Spry1 and Spry2 results in overgrowth of these muscles, which disrupts normal development of the glenoid fossa. Remarkably, condyle and disc formation are not affected in these mutants, demonstrating that the glenoid fossa is not required for development of these structures. Our findings demonstrate the importance of regulated RTK signaling during TMJ development and suggest multiple skeletal origins for the fossa. Notably, our work provides the evidence that the TMJ condyle and disc develop independently of the mandibular fossa. 相似文献
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Although polycystic ovary syndrome is associated with hypertension, hyperlipidaemia, and insulin resistance, mortality from cerebrovascular disease is not increased. We previously reported lower downstream resistance in the internal carotid artery in women with polycystic ovary syndrome. This study was designed to assess vascular reactivity by measuring the response to inhalation of 5% carbon dioxide. We studied 34 young women with polycystic ovary syndrome, 15 with symptomless polycystic ovaries, and 18 controls. 相似文献
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Host cell killing and bacterial conjugation require overlapping sets of genes within a 22-kb region of the Legionella pneumophila genome 总被引:19,自引:0,他引:19 下载免费PDF全文
Gil Segal Mary Purcell Howard A. Shuman 《Proceedings of the National Academy of Sciences of the United States of America》1998,95(4):1669-1674
A 22-kb DNA locus of Legionella pneumophila is described that contains 18 genes, 16 of which are required for macrophage killing (icm genes). In this paper two previously described icm loci were linked by the discovery of five genes located between the two loci. Four of the newly described genes are required for macrophage killing (icmMLKE) and one is dispensable. The 16 icm genes appeared to be organized as six individual genes (icmR, icmQ, icmG, icmC, icmD, and icmF), and four operons (icmTS, icmPO, icmMLKE, and icmJB). Four icm genes (icmP, icmO, icmL, and icmE) show significant sequence similarity to plasmid genes involved in conjugation, whereas the other icm genes were found not to bear any sequence similarity to database entries. We found that L. pneumophila can mediate plasmid DNA transfer at a frequency of 10−3 to 10−4 per donor. Strains containing null mutations in two icm genes (icmT and icmR) showed a severe reduction in conjugation frequency and macrophage killing. Strains containing an insertion in four other icm genes (icmF, icmE, icmC, and dotA) were shown to have a less severe defect in conjugation. Mutations in the other 11 icm genes had no effect on conjugation frequency. We currently do not know whether conjugation itself plays a role in macrophage killing. It is possible either that small plasmids can take advantage of an existing secretion system to be mobilized or that DNA transfer is required for human macrophage killing by L. pneumophila. 相似文献
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La Gruta NL Thomas PG Webb AI Dunstone MA Cukalac T Doherty PC Purcell AW Rossjohn J Turner SJ 《Proceedings of the National Academy of Sciences of the United States of America》2008,105(6):2034-2039
TCR repertoire diversity has been convincingly shown to facilitate responsiveness of CD8+ T cell populations to mutant virus peptides, thereby safeguarding against viral escape. However, the impact of repertoire diversity on the functionality of the CD8+ T cell response to cognate peptide-MHC class I complex (pMHC) recognition remains unclear. Here, we have compared TCRbeta chain repertoires of three influenza A epitope-specific CD8+ T cell responses in C57BL/6 (B6) mice: D(b)NP(366-374), D(b)PA(224-233), and a recently described epitope derived from the +1 reading frame of the influenza viral polymerase B subunit (residues 62-70) (D(b)PB1-F2(62)). Corresponding to the relative antigenicity of the respective pMHCs, and irrespective of the location of prominent residues, the D(b)PA(224)- and D(b)PB1-F2(62)-specific repertoires were similarly diverse, whereas the D(b)NP(366) population was substantially narrower. Importantly, parallel analysis of response magnitude, cytotoxicity, TCR avidity, and cytokine production for the three epitope-specific responses revealed no obvious functional advantage conferred by increased T cell repertoire diversity. Thus, whereas a diverse repertoire may be important for recognition of epitope variants, its effect on the response to cognate pMHC recognition appears minimal. 相似文献