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41.
HSV-1 antigen preparations solubilised from Vero cells by using either the non-ionic detergent Nonidet P40 or the zwitterionic detergent Empigen BB, and purified on sucrose density gradients or over a sucrose cushion, were tested by ELISA with anti-HSV-1 glycoprotein monoclonal antibodies and by radioimmunoprecipitation (RIP) with polyclonal HSV-1 antiserum. Amongst several proteins detected in these preparations, the four major HSV-1 glycoproteins, gB, gC, gD, and gE, were found to be present. Differences between NP40 or Empigen-solubilised HSV-1 antigen preparations with respect to two of these glycoproteins, gB and gE, were detected by using a small panel of monoclonal antibodies. Comparative studies in mice showed the Empigen-solubilised HSV-1 antigen preparations elicited greater antibody responses and greater protection against lethal HSV-1 challenge infection than the NP40-solubilised preparation. 相似文献
42.
Function and phenotype of immature CD4+ lymphocytes in healthy infants and early lymphocyte activation in uninfected infants of human immunodeficiency virus-infected mothers. 总被引:1,自引:0,他引:1
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K C Rich J N Siegel C Jennings R J Rydman A L Landay 《Clinical and Vaccine Immunology : CVI》1997,4(3):358-361
The function and phenotypes of CD4+ lymphocytes in infants are different than in adults and are modulated by maturational changes and exposure to environmental antigens. Infants of non-human immunodeficiency virus (HIV)-infected mothers and uninfected infants of HIV-infected mothers, 0 to 6 months of age, were examined for CD4+ lymphocyte function by in vitro interleukin-2 (IL-2) production and for CD4+ phenotypes by three-color flow cytometry. A minority of these uninfected infants (28%) had functional responses similar to those of healthy adult women (IL-2 production in response to anti-CD3, alloantigen, and mitogen), while the remainder were capable of responding to alloantigen and mitogen but not to anti-CD3. We did demonstrate reduced phytohemagglutinin-stimulated IL-2 production in uninfected infants born to HIV-seropositive mothers compared to that in infants from seronegative mothers. The proportions of CD3+ CD4+, CD4+ HLA-DR- CD38+, and CD4+ CD45RA+ RO- (naive) lymphocytes were much higher in infants than in adults, and the proportions of CD4+ CD45RA- RO+ (memory) and CD4+ CD25+ (IL-2 receptor-bearing) lymphocytes were lower in infants than in adults. The proportions of activated (CD4+ HLA-DR+ CD38+) and memory (CD4+ CD45RA- RO+) lymphocytes were increased in uninfected infants of HIV-infected mothers compared to infants of uninfected mothers. Therefore, T-helper-cell function is immature in many infants, but the CD4+ lymphocytes of some HIV-exposed, uninfected infants have been stimulated by antigen at an early age. 相似文献
43.
44.
Immunity to Influenza in Ferrets X. Intranasal Immunization of Ferrets with Inactivated Influenza A Virus Vaccines
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The response of ferrets after intranasal inoculation of inactivated A/Hong Kong/68 (H3N2) influenza virus vaccines is reported. Normal ferrets given either saline vaccine in drops or freeze-dried vaccine in an aerosol intranasally did not produce detectable serum or nasal hemagglutination inhibiting antibody and were found to be completely susceptible to challenge infection with A/Hong Kong/68 virus. Intranasal saline vaccine did not produce an additive effect on the response of ferrets simultaneously given the same vaccine intramuscularly with adjuvant. Ferrets primed by previous infection with A/PR/8/34 (H0N1) influenza virus, however, responded to intranasal immunization with saline A/Hong Kong/68 virus vaccine and produced serum and nasal antibody. These animals were found to be partially resistant to challenge infection, in contrast to similar animals given saline vaccine intramuscularly which were completely resistant to challenge infection. Primed ferrets did not respond after immunization with the freeze-dried aerosol vaccine, but this may have been due to a failure of the aerosol to be inhaled satisfactorily. 相似文献
45.
Stimulation of protective antibodies against type Ia and Ib group B streptococci by a type Ia polysaccharide-tetanus toxoid conjugate vaccine. 总被引:6,自引:6,他引:6
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M R Wessels L C Paoletti A K Rodewald F Michon J DiFabio H J Jennings D L Kasper 《Infection and immunity》1993,61(11):4760-4766
Antisera elicited by type Ia group B streptococci (GBS) contain antibodies that react with both type Ia and type Ib strains. Previous studies suggested that antibodies elicited by type Ia organisms recognized a carbohydrate antigen or epitope common to Ia and Ib strains. We now report the synthesis and immunogenicity testing of a type Ia polysaccharide-tetanus toxoid (Ia-TT) conjugate vaccine. Ia-TT elicited type Ia polysaccharide-specific immunoglobulin G antibodies in all three of the rabbits inoculated. In competitive enzyme-linked immunosorbent assay, these antibodies reacted with high affinity to type Ia polysaccharide and with lower affinity to the structurally related GBS type Ib polysaccharide. Despite the lower binding affinity of the Ia-TT-induced antibodies for the type Ib polysaccharide, Ia-TT antiserum opsonized not only type Ia GBS but also type Ib GBS for killing by human blood leukocytes. Ia-TT antiserum was also evaluated in a mouse model designed to test the efficacy of maternal antibodies in protecting neonates against GBS infection. Pups born to dams that had received Ia-TT antiserum were protected against lethal challenge with either type Ia or Ib GBS. These studies using a polysaccharide-protein conjugate as an immunogen support the view that the carbohydrate immunodeterminant recognized on Ib strains by Ia antisera is a common epitope contained within the structurally related Ia and Ib capsular polysaccharides. Although antibodies elicited by Ia-TT had protective activity against both Ia and Ib strains, these antibodies reacted with lower affinity to Ib than to Ia polysaccharide. 相似文献
46.
AIM--To determine the prevalence of a biochemically detectable hypercoagulable state, defined in terms of increased thrombin or plasmin generation, in patients with phenotypically characterised thrombophilia. METHODS--Plasma concentrations of the prothrombin activation peptide F1.2 and fibrin degradation (FbDP) and fibrinogen degradation products (FgDP) were measured by enzyme immunoassay in 104 patients deficient in natural anticoagulants, and 35 unaffected relatives. RESULTS--Increased concentrations of F1.2, FbDP, and FgDP were present in 18, 25, and 19 of 104 patients, respectively. There were no correlations between F1.2, FbDP, and FgDP concentrations, or between these parameters and concentrations of natural anticoagulants except for a negative correlation between protein C concentrations and FgDP (rho = -0.46, p = 0.009). CONCLUSION--A biochemically detectable hypercoagulable state is present in some patients with asymptomatic thrombophilia. Markers of plasmin generation may be increased more frequently in thrombophilia than markers of thrombin generation. This finding should prompt the inclusion of markers of plasmin generation in prospective longitudinal cohort studies to determine the predictive value of a hypercoagulable state, defined by either excessive thrombin or plasmin generation, for the development of venous thromboembolism. 相似文献
47.
A strain of neisseria meningitidis (LCDC 78189) isolated from the mother of a 3-year-old male with meningococcal meningitis was found to be antigenically distinct from the known serogroups A, B, C, D, H, I, K, X, Y, Z, 29E, and W135; it was designated serogroup L. Anti-78189 serum specifically agglutinated the homologous strain and three other strains which were isolated from the father and two other contacts of the child. Only those strains isolated from the contacts produced immunoprecipitates with the anti-78189 serum by the antiserum-agar method. A structurally unique capsular polysaccharide which was obtained from strain 78189 in a highly purified state was demonstrated to be the antigen responsible for the serological properties of the strain. The polysaccharide formed a precipitin band with the anti-78189 serum but not with the meningococcal grouping sera, and it was also able to absorb both the agglutinating and precipitating activity from the anti-78189 serum. 相似文献
48.
C A Axiotis J Fuks T A Jennings A S Kadish 《Archives of pathology & laboratory medicine》1988,112(8):850-851
An 87-year-old man was found to have a lymphoma in the deep soft tissue of the right shoulder with concomitant central nervous system involvement. There was no evidence of cutaneous, peripheral lymph node, mediastinal, abdominal, or bone marrow involvement. Light microscopic, ultrastructural, and immunohistochemical evaluation characterized the neoplasm as a peripheral T-cell lymphoma. Lymphomas presenting in soft tissue are rare, and the few well-documented cases in the literature are of B-cell origin. We report a T-cell lymphoma presenting in the soft tissue of the extremity, and delineate its clinicopathologic features. 相似文献
49.
Immunological clearance of 75Se-labelled Trypanosoma brucei in mice. III. Studies in animals with acute infections. 总被引:1,自引:0,他引:1
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Using trypanosomes labelled with [75Se]-methionine a series of experiments was conducted to investigate antibody production in mice with acute fulminating T. brucei infections. As measured by the hepatic uptake of radiolabelled parasites, we were unable to demonstrate any evidence of antibody-mediated uptake by the liver in such mice. It was concluded that this was not due to impaired macrophage function but was caused by the inability of antibody production to cope with the massive parasitaemias produced by rapidly-replicating infections so that effective opsonization of the parasites did not occur. In contrast, a train of trypanosome which causes a more chronic infection, although initially having a similar replication, although initially having a similar replication rate, subsequently switched t a slower one and thereby allowed antibody to reach levels which permitted effective opsonization. There was no evidence that the parasite caused any significant suppression of antibody responses in these acute infections since inoculation with trypanosomes of one stock at the same time as vaccination with irradiated organisms of a second stock did not prevent the development of antibody to the latter, as measured by the hepatic uptake of radiolabelled parasites. 相似文献
50.
We describe identical twin sisters born to nonconsanguineous, healthy parents. Both twins had situs viscerum inversus and developed hypertrophic cardiomyopathy in adulthood. 相似文献