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991.
Yang JQ Chun T Liu H Hong S Bui H Van Kaer L Wang CR Singh RR 《European journal of immunology》2004,34(6):1723-1732
Mechanisms responsible for the development of autoimmune skin disease in humans and animal models with lupus remain poorly understood. In this study, we have investigated the role of CD1d, an antigen-presenting molecule known to activate natural killer T cells, in the development of inflammatory dermatitis in lupus-susceptible MRL-lpr/lpr mice. In particular, we have established MRL-lpr/lpr mice carrying a germ-line deletion of the CD1d genes. We demonstrate that CD1d-deficient MRL-lpr/lpr mice, as compared with wild-type littermates, have more frequent and more severe skin disease, with increased local infiltration with mast cells, lymphocytes and dendritic cells, including Langerhans cells. CD1d-deficient MRL-lpr/lpr mice had increased prevalence of CD4(+) T cells in the spleen and liver and of TCR alpha beta (+)B220(+) cells in lymph nodes. Furthermore, CD1d deficiency was associated with decreased T cell production of type 2 cytokines and increased or unchanged type 1 cytokines. These findings indicate a regulatory role of CD1d in inflammatory dermatitis. Understanding the mechanisms by which CD1d deficiency results in splenic T cell expansion and cytokine alterations, with increased dermal infiltration of dendritic cells and lymphocytes in MRL-lpr/lpr mice, will have implications for the pathogenesis of inflammatory skin diseases. 相似文献
992.
Elliott DE Setiawan T Metwali A Blum A Urban JF Weinstock JV 《European journal of immunology》2004,34(10):2690-2698
Inflammatory bowel disease (IBD) is prevalent in industrialized countries, but rare in less-developed countries. Helminths, common in less-developed countries, may induce immunoregulatory circuits protective against IBD. IL-10(-/-) mice given piroxicam develop severe and persistent colitis. Lamina propria mononuclear cells from colitic IL-10(-/-) mice released IFN-gamma and IL-12. The ongoing piroxicam-induced colitis could be partially blocked with anti-IL-12 monoclonal antibody suggesting that the inflammation was at least partly IL-12 dependent. Colonization of piroxicam-treated colitic IL-10(-/-) mice with Heligmosomoides polygyrus (an intestinal helminth) suppressed established inflammation and inhibited mucosal IL-12 and IFN-gamma production. H. polygyrus augmented mucosal IL-13, but not IL-4 or IL-5 production. Transfer of mesenteric lymph node (MLN) T cells from IL-10(-/-) animals harboring H. polygyrus into colitic IL-10(-/-) recipients inhibited colitis. MLN T cells from worm-free mice did not. Foxp3 (scurfin) drives regulatory T cell function. H. polygyrus enhanced Foxp3 mRNA expression in MLN T cells that had regulatory activity. This suggests that H. polygyrus inhibits ongoing IL-10(-/-) colitis in part through blocking mucosal Th1 cytokine production. Resolution of inflammation is associated with increased IL-13 production and can be adoptively transferred by MLN T cells. 相似文献
993.
孕鼠被动吸烟对子代学习记忆功能及海马神经生长因子含量的影响 总被引:5,自引:0,他引:5
目的 探讨孕鼠被动吸烟对子代学习记忆功能的影响及其机制。方法 采用反映学习记忆功能的水迷宫法测试大鼠神经行为的改变,IRMA法测定大鼠海马神经生长因子的含量变化。结果 孕期被动吸烟使仔鼠学习记忆能力下降,海马神经生长因子含量明显降低。结论 孕期被动吸烟降低仔鼠学习记忆功能与海马神经生长因子代谢的失调有关。 相似文献
994.
High-efficiency gene transfer to primary T lymphocytes by recombinant adenovirus vectors 总被引:3,自引:0,他引:3
Zhi Chen Matti Ahonen Heli Hmlinen Jeffrey M. Bergelson Veli-Matti Khri Riitta Lahesmaa 《Journal of immunological methods》2002,260(1-2):79-89
Recombinant, replication-deficient adenoviruses are efficient vectors for gene transfer to a wide range of cell types, with the exception of T lymphocytes. Here, we show that primary T lymphocytes from peripheral blood, cord blood, and the Jurkat T cell line are efficiently transduced by recombinant adenovirus. Nearly 100% infection efficiency of primary T cells is obtained with high multiplicity of infection (MOI) (5000) of recombinant adenovirus coding for lacZ. Similar infection efficiency by adenovirus-mediated gene transfer was obtained at lower MOI (3000) by activating primary T cells with PHA and PMA. Addition of cationic liposomes together with RAdlacZ markedly enhanced the infection efficiency at lower MOI (1000) resulting in over 90% infection efficiency. Primary T cells express low levels of coxsackievirus and adenovirus receptor (CAR), a cell surface receptor for adenovirus fiber attachment, as well as vβ3 and vβ5 integrins, cellular receptors for adenovirus internalization. This suggests that adenovirus entry to T cells at high MOI is mediated by other mechanisms. In conclusion, these results demonstrate that genes can be efficiently transferred to primary lymphocytes by adenovirus vectors at high MOI or in combination with cationic liposomes. 相似文献
995.
Dissecting the complexity of the memory T cell response 总被引:2,自引:0,他引:2
Memory immune responses are classically attributed to the reactivation of long-lived, antigen-specific T lymphocytes that
persist in a quiescent state. Determining mechanisms for the generation of memory T cells and dissecting the functional nature
of the memory T cell pool has been encumbered by an inability to distinguish recently activated effector T cells from memory
T cells. We have established new activation and biochemical criteria that distinguish effector and memory T cells and have
applied these criteria to follow memory generation from activated cells in vivo. We found that the resultant memory T cell
pool is heterogeneous and consists of effector-like and resting memory-like subsets that differ in expression of the homing
receptor, CD62L. We discuss these findings in the context of memory T cell heterogeneity identified in human and mouse systems.
These results suggest that more than one type of previously activated T cell can mediate recall or memory immune responses
and that elucidating the fundamental phenotypic and functional features of memory T cell subsets is therefore critical to
deciphering the complex nature of the memory immune response. 相似文献
996.
The natural ligands of the S100 EF hand proteins S100A8 and A9 [myeloid-related proteins 8 and 14] have long been searched for in order to further the understanding of the role of the S100A8/A9-expressing monocyte subpopulation in progressing inflammatory processes. We demonstrate that S100A8, S100A9 and the S100A8/A9 heterodimeric complex bind to human dermal microvascular endothelial cell line (HMEC)-1 with an increasing binding capacity progressing from S100A8 < or = S100A9 < or = S100A8/A9. Similar results were obtained in the apolipoprotein E knockout mouse model, where preferably recombinant S100A9 but no S100A8 bound to the endothelium of the aorta ascendens. The binding of the S100A8/A9 heterodimer complex to activated HMEC-1 is specific as demonstrated by a dose-responding and satiable binding curve and the competition of FITC-labeled versus unlabeled protein. The protein character of the binding site was proven by treatment with trypsin. S100A8/A9 binding to HMEC-1 is inducible by lipopolysaccharide and tumor necrosis factor-alpha, and in the presence of calcium. A 163-kDa protein was isolated from a cell lysate of activated HMEC-1 cells using an affinity-chromatography protocol. The endothelial cell-associated ligand proteins isolated by the use of the S100A9 monomer and the S100A8/A9 dimer were subjected to mass spectrometry for protein identification. Clearly, alpha(2)-macroglobulin was identified as a binding partner for the S100A9 monomer, whereas no protein could be identified from the database for the ligand of the S100A8/A9 dimer. 相似文献
997.
Stefania Damiani Maria Grazia Cattani Laura Buonamici V. Eusebi 《Virchows Archiv : an international journal of pathology》1998,432(5):433-440
Cells showing abundant, finely vacuolized cytoplasm (foam cells) are found frequently in most benign lesions of the breast
and in certain malignant breast tumours. The origin of mammary foam cells (FCs) has not been clarified, and we therefore studied
the morphological features of mammary FCs in a series of 50 benign lesions. The FCs were subdivided, on the basis of their
distribution into FCs lining the glandular lumina, intraluminal FCs, intraepithelial-pagetoid FCs, and stromal FCs. The lesions
were tested with a panel of antibodies against macrophage (MAC 387, CD68) and epithelial (epithelial membrane antigen [EMA],
gross cystic disease fluid protein 15 [GCDFP15] and cytokeratin) markers. The lesions were examined for the presence of PIP/GCDFP15-specific
mRNA by an in situ hybridization technique. Three different types of FCs were identified. Type A FCs are epithelial cells
(positivity with EMA and cytokeratin) and show apocrine differentiation (positivity with GCDFP15 antiserum and expression
of PIP/GCDFP15 mRNA). Type B FCs are of macrophage origin, as they are positive with the macrophage markers and lack cytokeratin
and PIP/GCDFP15 mRNA. Finally, type C FCs show an intermediate profile between an epithelial cell and a macrophage: they are
both CD68 and GCDFP15 positive and show a thin peripheral rim of positivity with anti-cytokeratin antibody. They lack PIP/GCDFP15
mRNA. Our results indicate the possibility of a spectrum of phenotypes in mammary FCs, from epithelial-apocrine cells to macrophage-derived
phagocytic cells.
Received: 19 September 1997 / Accepted: 29 December 1997 相似文献
998.
Miodrag ?oli? Vesna Ili? Milo? D. Pavlovi? Takuya Tamatani Masayuki Miyasaka 《Clinical & developmental immunology》1996,5(1):37-51
The effects of monoclonal antibodies (mAbs) to cell-surface molecules, divalent cations,
and various cell-signaling and metabolic inhibitors on the binding of thymocytes to rat
thymic dendritic cells (TDC) were studied using a rosette assay. It was found that TDC/thymocyte adhesion was stronger and faster at 37°C than at 4°C. Flow cytometric analysis demonstrated that bound thymocytes were predominantly CD4+CD8+ and CD4+CD8-, but in comparison to the phenotype of whole thymocytes, they were enriched in the mature
TCRαβhi subset. The binding of thymocytes to TDC at 37°C was almost completely
dependent on Ca2+ and Mg2+ and partly on an intact cytoskeleton and calmodulin-dependent
protein kinase. The adhesion was independent of new protein synthesis and the activities of protein kinases A and C, tyrosine kinases, as well as phosphotyrosine protein phosphatases. The TDC/thymocyte adhesion at 37°C was partly blocked by anti-LFA-1
(WT.1), anti-CD18 (WT.3), and anti-ICAM-1 (1A29) mAb. MAbs to class II MHC (OX-3 and OX-6), CD4 (W3/25), CD8 (OX-8), and αβTCR (R73) stimulated the adhesion via an LFA-1-dependent pathway, whereas an anti-CD45 mAb (G3C5) stimulated the rosette formation
independently of LFA-1. MAbs to CD2 (OX-34), CD11b (ED7), CD11b/c (OX-42), and class I MHC (OX-18) were without significant effects on the adhesion process. 相似文献
999.
Peripheral blood and synovial fluid T cells differ in their response to alloantigens and recall antigens presented by dendritic cells.
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A J Stagg B Harding R A Hughes A Keat S C Knight 《Clinical and experimental immunology》1991,84(1):72-77
Properties of T cells from inflammatory lesions were analysed by comparing the response of peripheral blood (PB) and synovial fluid (SF) T cells from 19 patients with a range of arthropathies to enriched allogeneic dendritic cells (DC) in a primary mixed leucocyte reaction (MLR). In 17 patients the proliferative response of SF T cells was significantly (P less than 0.05) less than that of PB lymphocytes. The reduced response of SF T cells was observed in all disease categories studied and could not be attributed to differences in cell number requirements or response kinetics. Addition of recombinant interleukin-2 enhanced the response of SF T cells in a dose-dependent manner. Cell mixing experiments suggested that active suppression was not the underlying mechanism of the poor MLR response of SF T cells. In contrast to the MLR response. SF T cells were able to mount vigorous proliferative responses to recall antigen presented by autologous antigen-presenting cells. The possibility is discussed that T cells compartmentalized at inflammatory lesions are a unique population with a diminished ability to interact with DC and respond to primary stimuli but an ability to respond to secondary antigenic challenge. 相似文献
1000.
Terry L. Riss Masami Ogasawara Kenneth P. Karey David Danielpour Betty H. Stewart David A. Sirbasku 《Methods in Cell Science》1986,10(2):133-150
Summary Serum-free defined media have been developed for assay of the mitogenic effects of growth factors on human MCF-7, human T-47D, and mouse COMMA-D mammary cells as well as for identification of mitogens and inhibitors of GH4C1 rat pituitary tumor cell growth. These lines were shown to grow in vivo in response to a variety of hormones including estrogens and thyroid hormones. With mammary cells, complete hormonally and nutritionally defined media were established that supported continuous passage at 50 to 90% of the serum stimulated rate. The strategy used to measure mitogens for mammary cells was to identify nutritional conditions where the growth rate was reduced greatly without impairing the response to picomolar to nanomolar concentration of growth factors. The effects of polypeptide growth factors and tissue extracts were estimated by their addition to basal medium and measuring cell number increases or labeled thymidine incorporation into DNA. In a variation of this methodology, the MTW9/PL2 rat mammary cells were used to identify secreted autocrine growth factors; nutritionally defined conditions were sought for growth of these rat cells in the complete absence of exogenous growth factors. The factors secreted into the medium were detected by bioassays with COMMA-D or MCF-7 mammary cell lines. The effects of growth factors-inhibitors on pituitary cells were measured by a related method; the GH4C1 cells were grown at less than optimal rates in a defined medium designated TRM-1. Addition of mitogens to TRM-1 stimulated pituitary cell growth whereas addition of inhibitors caused reduced levels of growth. The methods described in this report offer new means of assaying growth factors-inhibitors for a range of mammary and pituitary tumor cells. 相似文献