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61.
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63.
Botto LD Mulinare J Yang Q Liu Y Erickson JD 《American journal of medical genetics. Part A》2004,(2):113-116
Recent reports suggest that women carrying certain polymorphisms of folate genes associated with suboptimal folate status might be at increased risk for having a child with Down syndrome or other autosomal trisomies, and hypothesized that maternal use of multivitamin supplements might reduce such risk. To evaluate this hypothesis, we examined data from a population-based case-control study, and contrasted cases of Down syndrome, trisomy 18, and trisomy 13, with unaffected controls. Periconceptional multivitamin use, compared to no such use, was associated with an odds ratio (OR) of 0.9 (95% confidence interval [CI], 0.6-1.3) for having a pregnancy affected by an autosomal trisomy. The OR was 0.8 (95% CI, 0.5-1.3) for Down syndrome and 1.4 (95% CI, 0.5-3.6) for trisomies 13 and 18, with little variation by maternal race or age. Periconceptional multivitamin use was not associated with a major reduction in the risk for common autosomal trisomies. 相似文献
64.
Molecular and Cellular Analysis of Human T Lymphocytes Expressing γδ T-Cell Receptor 总被引:1,自引:0,他引:1
65.
Human gammadelta T cells: a nonredundant system in the immune-surveillance against cancer. 总被引:4,自引:0,他引:4
Marina Ferrarini Elisabetta Ferrero Lorenzo Dagna Alessandro Poggi Maria Raffaella Zocchi 《Trends in immunology》2002,23(1):14-18
Down-regulation of expression of MHC alleles, as well as tumor-specific antigens, is observed frequently during tumor progression, resulting in an impairment of MHC-restricted, alphabeta-T-cell-mediated, tumor-specific immunity. Given the unique set of antigens recognized and the lack of requirement for classical antigen-presenting molecules, gammadelta T cells might, therefore, represent a nonredundant system in anticancer surveillance, as proposed for the immune response against pathogens. Evidence that gammadelta and alphabeta T cells make distinct contributions to anticancer surveillance has been provided recently in mice. Here, we discuss the potential role played by resident Vdelta1(+) and circulating Vdelta2(+) T cells in the defense against solid tumors and hematological malignancies. 相似文献
66.
Lorenzo Moretta Guido Ferlazzo Cristina Bottino Massimo Vitale Daniela Pende Maria Cristina Mingari Alessandro Moretta 《Immunological reviews》2006,214(1):219-228
Summary: The different cell types of the innate immune system can interact with each other and influence the quality and strength of an immune response. The cross talk between natural killer (NK) cells and myeloid dendritic cells (DCs) leads to NK cell activation and DC maturation. Activated NK cells are capable of killing DCs that fail to undergo proper maturation ('DC editing'). Encounters between NK cells and DCs occur in both inflamed peripheral tissues and lymph nodes, where both cell types are recruited by chemokines released in the early phases of inflammatory responses. Different NK cell subsets (CD56bright CD16− versus CD56+ CD16+ ) differ in their homing capabilities. In particular, CD56bright CD16− NK cells largely predominate the lymph nodes. In addition, these two subsets display major functional differences in their cytolytic activity, cytokine production, and ability to undergo proliferation. NK cell functions are also greatly influenced by the presence of polarizing cytokines such as interleukin (IL)-12 and IL-4. The cytokine microenvironment reflects the presence of different cell types that secrete such cytokines in response to microbial products acting on different Toll-like receptors (TLRs). Moreover, NK cells themselves can respond directly to microbial products by means of TLR3 and TLR9. Thus, it appears that the final outcome of a response to microbial infection may greatly vary as a result of the interactions occurring between different pathogen-derived products and different cell types of the innate immunity system. These interactions also determine the quality and strength of the subsequent adaptive responses. Remarkably, NK cells appear to play a key role in this complex network. 相似文献
67.
IL-21 induces both rapid maturation of human CD34+ cell precursors towards NK cells and acquisition of surface killer Ig-like receptors 总被引:9,自引:0,他引:9
Sivori S Cantoni C Parolini S Marcenaro E Conte R Moretta L Moretta A 《European journal of immunology》2003,33(12):3439-3447
The NK cell maturation from CD34(+) Lin(-) hematopoietic cell precursors is a complex process that requires the direct contact with stromal cells and/or the synergistic effect of different cytokines. In this study we show that IL-21 is capable of inducing an accelerated NK cell maturation when added to cultures of CD34(+) Lin(-) cells isolated from human cord blood supplemented with IL-15, Flt3-L and SCF. After 25 days of culture, 50% of CD56(+) cells expressed various NK cell markers including the NKp46 and NKp30 triggering receptors, the CD94/NKG2A inhibitory receptor and CD16. At day 35, substantial fractions of NK cells expressed KIR, CD8 and CD2, i.e. surface markers expressed by mature NK cells, that are virtually undetectable in developing NK cells cultured in the absence of IL-21. Remarkably, similar to mature NK cells all these markers were included in the CD56(dim) cell fraction, while the CD56(bright) population was only composed of CD94/NKG2A(-) and CD94/NKG2A(+) cells. Thus, IL-21 allows the induction of a full NK cell maturation in vitro and offers an important tool for dissecting the molecular mechanisms involved in different steps of NK cell maturation and in the acquisition of a mature KIR repertoire. 相似文献
68.
Anna Siniscalchi Irene Badini Antonio Cintra Kjell Fuxe Clementina Bianchi Lorenzo Beani 《Neuroscience letters》1992,140(2):235-238
Spontaneous and electrically evoked endogenous acetylcholine release and [3H]-choline efflux from slices of guinea pig nucleus basalis magnocellularis (nbM) were studied. Tetrodotoxin reduced the spontaneous endogenous release by 55%, while the Ca2+-free medium reduced it by about 30%. Evoked [3H]-choline efflux was Na+ and Ca2+ dependent and frequency related. Physostigmine, 30 μM, nearly halved the stimulation-evoked efflux; atropine, 0.15 μM, not only antagonized, but even reversed this effect into facilitation. Pirenzepine, 1 μM, and AFDX 116, 1 μM, were less effective than atropine, and reversed the inhibitory effect of physostigmine only when applied together. 4-DAMP, 0.01 μM, was ineffective. These findings indicate that acetylcholine release in guinea pig nbM slices is inhibited by the cooperation of muscarinic autoreceptors, possibly belonging to the M1 and M2 subclasses. 相似文献
69.
Mario Cocco Cristiana Bellan Roxane Tussiwand Davide Corti Elisabetta Traggiai Stefano Lazzi Susanna Mannucci Lucio Bronz Nazzareno Palummo Chiara Ginanneschi Piero Tosi Antonio Lanzavecchia Markus G. Manz Lorenzo Leoncini 《The American journal of pathology》2008,173(5):1369-1378
Recent studies suggest that Epstein-Barr virus (EBV) can infect naïve B cells, driving them to differentiate into resting memory B cells via the germinal center reaction. This hypothesis has been inferred from parallels with the biology of normal B cells but has never been proven experimentally. Rag2−/− γc−/− mice that were transplanted with human CD34+ cord blood cells as newborns were recently shown to develop human B, T, and dendritic cells, constituting lymphoid organs in situ. Here we used this model to better define the strategy of EBV infection of human B cells in vivo and to compare this model system with different conditions of EBV infection in humans. Our results support the model of EBV persistence in vivo in cases that were characterized by follicular hyperplasia and a relatively normal CD4+ and CD8+ T-cell distribution. Intriguingly, in cases that were characterized by nodular and diffuse proliferation with a preponderance of CD8+ T cells, similar to infectious mononucleosis, EBV still infects naïve B cells but also induces clonal expansion and ongoing somatic mutations without germinal center reactions. Our results reveal different strategies of EBV infection in B cells that possibly result from variations in the host immune response. Future experiments might allow understanding of the mechanisms responsible for persistent EBV infection and provide targets for more highly tailored therapeutic interventions. 相似文献
70.
Human T Cell Subpopulations in Normal and Pathologic Conditions 总被引:3,自引:0,他引:3