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91.
The effect of in vitro human immunodeficiency virus infection on dendritic-cell differentiation and function 总被引:2,自引:4,他引:2
Canque B; Rosenzwajg M; Camus S; Yagello M; Bonnet ML; Guigon M; Gluckman JC 《Blood》1996,88(11):4215-4228
CD1a+ dendritic cells (DC) differentiate from a major population of nonadherent CD13(hi)lin- cells that appear when human cord blood CD34+ hematopoietic progenitor cells are cultured with stem-cell factor, granulocyte/macrophage (MA) colony-stimulating factor, and tumor necrosis factor-alpha (TNF-alpha) for 5 days. CD13hilin- cells, which also comprise MA and granulocyte precursors, are CD4+ and can thus be targets of human immunodeficiency virus (HIV). Low replication was noted when these day 5 cells were infected with lymphotropic HIV-1LA1 (p24: < or = 4 ng/mL on day 8 postinfection [PI]), while high virus production occurred with MA-tropic HIV-1Ba-L, HIV-1Ada, or HIV-1-m-n. (p24: 50 to > or = 1,000 ng/mL). Strong cytopathicity (CPE) was then observed in nonadherent cells as in adherent MA. However, FACS analysis on day 7 PI showed that HIV did not affect differentiation of DC that survived CPE: apart from CD4 downmodulation related to HIV production, overall expression of CD40, CD80, and CD86 costimulatory molecules, and of HLA-DR, was unchanged relative to controls. At that time, the capacity of DC from HIV-infected cultures to stimulate the mixed leukocyte reaction was only altered less than 10-fold. Immunocytochemistry on day 7 PI showed that most HIV-infected cells were included in syncytia that were stained by anti-CD1a, anti-S100, and anti-CD14 antibodies, indicating that syncytia consisted of DC and cells of the MA lineage. Polymerase chain reaction analysis of FACS- sorted CD1a+ cells confirmed that they harbored then HIV DNA. Viral DNA was also detected in CD1a+ DC from noninfected cultures that had been exposed to HIV only after sorting. Therefore, we examined whether in infected cultures DC precursors were infected at the onset or if virus spread later from other infected cells to differentiated DC. This was answered by showing that, 24 hours postexposure to HIV, viral DNA was preferentially detected in day 5 sorted CD13hilin- versus CD13hilin- cells, and that it was found in the CD1a+ progeny of CD13(hi)lin- cells 48 hours later. In addition, HIV replication did not affect myeloid clonogenic progenitors in day 0 to day 7 PI cultures, although viral DNA was detected in colony-forming unit-granulocyte/macrophage (CFU- GM)/CFU-M colonies derived from day 3 and 7 PI cultures. Thus, precursors of DC and their progeny are susceptible to HIV in vitro, but, apart from CPE, the effect of virus production on DC differentiation or function is limited. 相似文献
92.
Aplastic anemia and paroxysmal nocturnal hemoglobinuria: search for a pathogenetic link 总被引:5,自引:4,他引:5
Griscelli-Bennaceur A; Gluckman E; Scrobohaci ML; Jonveaux P; Vu T; Bazarbachi A; Carosella ED; Sigaux F; Socie G 《Blood》1995,85(5):1354-1363
The association of paroxysmal nocturnal hemoglobinuria (PNH) and aplastic anemia (AA) raises the yet unresolved questions as to whether these two disorders are different forms of the same disease. We compared two groups of patients with respect to cytogenetic features, glycosylphosphatidylinositol (GPI)-linked protein expression, protein C/protein S/thrombomodulin/antithrombin III activity, and PIG-A gene expression. The first group consisted of eight patients with PNH (defined as positive Ham and sucrose tests at diagnosis), and the second, 37 patients with AA. Twelve patients with AA later developed a PNH clone. Monoclonal antibodies used to study GPI-linked protein expression (CD14 [on monocytes], CD16 [on neutrophils], CD48 [on lymphocytes and monocytes], CD67 [on neutrophils and eosinophils], and, more recently, CD55, CD58, and CD59 [on erythrocytes]) were also tested on a cohort of 20 normal subjects and five patients with constitutional AA. Ham and sucrose tests were performed on the same day as flow- cytometric analysis. Six of 12 patients with AA, who secondarily developed a PNH clone, had clinical symptoms, while all eight patients with PNH had pancytopenia and/or thrombosis and/or hemolytic anemia. Cytogenetic features were normal in all but two patients. Proteins C and S, thrombomodulin, and antithrombin III levels were within the normal range in patients with PNH and in those with AA (with or without a PNH clone). In patients with PNH, CD16 and CD67 expression were deficient in 78% to 98% of the cells and CD14 in 76% to 100%. By comparison, a GPI-linked defect was detected in 13 patients with AA, affecting a mean of 32% and 33% of CD16/CD67 and CD14 cell populations, respectively. Two of three tested patients with PNH and 1 of 12 patients with AA had a defect in the CD48 lymphocyte population. In a follow-up study of our patient cohort, we used the GPI-linked molecules on granulocytes and monocytes investigated earlier and added the study of CD55, CD58, and CD59 on erythrocytes. Two patients with PNH and 14 with AA were studied for 6 to 13 months after the initial study. Among patients with AA, four in whom no GPI-anchoring defect was detected in the first study had no defect in follow-up studies of all blood-cell subsets (including erythrocytes). Analysis of granulocytes, monocytes, and erythrocytes was performed in 7 of 13 AA patients in whom affected monocytes and granulocytes were previously detected. A GPI-anchoring defect was detected on erythrocytes in five of six.(ABSTRACT TRUNCATED AT 400 WORDS) 相似文献
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97.
Chemoattractant-induced changes in surface expression and redistribution of a functional ligand for P-selectin on neutrophils 总被引:4,自引:0,他引:4
Adhesion between platelets and neutrophils is mediated through the interaction of P-selectin on activated platelets with a carbohydrate- containing structure on neutrophils, and occurs under both static and shear conditions. Recent studies using flow chambers have shown that neutrophils become activated after binding to surface-adherent platelets expressing P-selectin. The objective of the present study was to investigate the effect of such activation on the interactions of platelet P-selectin with its ligand on neutrophils. Flow cytometric analyses using P-selectin chimeras revealed that activation induced a rapid and marked reduction in chimera binding, with levels of binding decreased by 71% after 15 minutes of stimulation with the chemotactic agent, FMLP. Using a visual assay of platelet-neutrophil rosetting, we showed that the P-selectin ligand was translocated and clustered at the uropod of neutrophils following the shape changes and polarization induced by chemotactic stimulation. Activated neutrophils bound to surface-adherent platelets also displayed the clustering of P-selectin ligand at the uropod, and these neutrophils detached from the platelets when a shear stress (2 dynes/cm2) was applied through the adhesion chamber. These results indicate that chemotactic stimulation of neutrophils induces changes in the surface expression and distribution of a biologically relevant ligand for P-selectin, and that these changes might influence the adhesive interactions occurring between neutrophils and activated platelets. 相似文献
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99.
Hepatitis C virus infection and chronic liver disease in children with leukemia in long-term remission 总被引:2,自引:0,他引:2
Locasciulli A; Gornati G; Tagger A; Ribero ML; Cavalletto D; Cavalletto L; Masera G; Shulman HM; Portmann B; Alberti A 《Blood》1991,78(6):1619-1622
Antibody to the recently identified hepatitis C virus (HCV) was investigated in sera of 50 leukemic children who had chronic liver disease (CLD), observed for 1 to 12.6 years after therapy withdrawal. All patients were tested for anti-HCV at regular intervals: Ortho- enzyme-linked immunosorbent assay (ELISA) test was performed in all cases. Reactive sera were also tested by recombinant immunoblotting assay to define the specificity of the results obtained by ELISA. Twelve cases (24%) were persistently positive (group A), 11 (22%) were transiently anti-HCV+ positive (group B), and 27 (54%) were negative. Mean SGPT peak during follow-up was significantly higher in group A (P = .014, A v B and P less than .00001, A v C). SGPT normalized off- therapy in 1 of 12 cases (group A), 10 of 11 (group B), and 19 of 27 (group C) (P = .0004, A v B and P = .012, A v C). Accordingly, liver histology, available in 37 patients, showed signs of chronic hepatitis in all patients in group A while most patients in group B and C had less severe liver lesions. These results indicate that HCV plays a significant role in the etiology of chronic hepatitis in leukemic patients and that persistent anti-HCV activity correlates with a more severe CLD, which could jeopardize the final prognosis of children cured of leukemia. 相似文献
100.
Low-grade malignant lymphoma, hepatitis C virus infection, and mixed cryoglobulinemia 总被引:14,自引:3,他引:14
Pozzato G; Mazzaro C; Crovatto M; Modolo ML; Ceselli S; Mazzi G; Sulfaro S; Franzin F; Tulissi P; Moretti M 《Blood》1994,84(9):3047-3053
Because a close relationship has been established between mixed cryoglobulinemia and hepatitis C virus (HCV) infection, the clinical, histologic, and virologic findings of 31 patients affected by mixed cryoglobulinemia have been determined. HCV infection was investigated by the presence of anti-HCV antibodies and by polymerase chain reaction (PCR) amplification of the 5' untranslated region (5'UTR), and the genotype of HCV was also determined according to Okamoto et al (J Gen Virol 73:673, 1992). A bone marrow (BM) biopsy was performed in all patients, and liver and kidney biopsies were performed when indicated. The prevalence of anti-HCV antibodies was high (83.9%); polymerase chain reaction amplification of the 5' untranslated region was positive in 26 subjects (83.9%), and Core region amplification in 26 of 27 subjects (96.2%). A high prevalence of genotype II was found (76.6%). Chronic liver disease was present in 15 (48%) patients. BM biopsy specimens showed the presence of low-grade non-Hodgkin's lymphomas in 12 cases (38.7%), whereas, in 11 patients (35.5%), the BM infiltration was not monoclonal (reactive). Mixed cryoglobulinemia is closely associated with HCV infection. Apparently, only 1 patient was not infected by the virus. Several HCV genotypes are involved in the pathogenesis of mixed cryoglobulinemia. The disease is associated with a high prevalence of low-grade non-Hodgkin's lymphomas. 相似文献