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991.
Synergistic effect of interleukin-2 and a vaccine of irradiated melanoma cells transfected to secrete staphylococcal enterotoxin A 总被引:4,自引:0,他引:4
We have previously reported that immunization of mice with melanoma cells transfected to secrete the superantigen, Staphylococcal enterotoxin A (SEA), increased the production of antibodies to the B700 melanoma antigen, stimulated the production of endogenous interleukin 2 (IL-2), activated the expression of CD4, CD8 and CD25 T cell markers and enhanced NK cell activity. Now we show that immunization of mice with a vaccine of irradiated sea-transfected melanoma cells coupled with IL-2 therapy was even more effective in inhibiting the growth of primary melanoma tumors and the development of lung metastases than was the irradiated melanoma cell vaccine alone or IL-2 alone. The morphological and immunological effectiveness of the therapy was dose-dependent on IL-2. 相似文献
992.
Enhancement of human immunodeficiency virus type 1-DNA vaccine potency through incorporation of T-helper 1 molecular adjuvants 总被引:7,自引:0,他引:7
Summary: It is clear that the development of a safe and effective vaccine for human immunodeficiency virus type 1 (HIV‐1) remains a crucial goal for controlling the acquired immunodeficiency syndrome epidemic. At present, it is not clear what arm of the immune response correlates with protection from HIV‐1 infection or disease. Therefore, a strong cellular and humoral immune response will likely be needed to control this infection. Among different vaccine alternatives, DNA vaccines appeared more than a decade ago, demonstrating important qualities of inducing both humoral and cellular immune responses in animal models. However, after several years and various clinical studies in humans, supporting the safety of the HIV‐DNA vaccine strategies, it has become clear that their potency should be improved. One way to modulate and enhance the immune responses induced by a DNA vaccine is by including genetic adjuvants such as cytokines, chemokines, or T‐cell costimulatory molecules as part of the vaccine itself. Particularly, vaccine immunogenicity can be modulated by factors that attract professional antigen‐presenting cells, provide additional costimulation, or enhance the uptake of plasmid DNA. This review focuses on developments in the coadministration of molecular adjuvants for the enhancement of HIV‐1 DNA‐vaccine potency. 相似文献
993.
994.
995.
A membrane cofactor protein transgenic mouse model for the study of discordant xenograft rejection 总被引:1,自引:0,他引:1
Nikos Yannoutsos Jan N. M. IJzermans Clara Harkes Fred Bonthuis Chun-Yan Zhou David White Richard L. M. Marquet & Frank Grosveld 《Genes to cells : devoted to molecular & cellular mechanisms》1996,1(4):409-419
Background: In recent years, interest has been revived in the possibility of transplanting organs into humans from a phylogenetically disparate species such as the pig (xenotransplantation). Such discordant xenografts, however, are subject to hyperacute rejection (HAR) and activation of host complement plays a major role in this rejection. This problem may be solved through the use of transgenic technology by providing the grafted tissue with molecules that down-regulate the action of host complement.
Results: Transgenesis with a yeast artificial chromosome (YAC) was used to produce transgenic mice with the complete genomic gene of the human complement regulator membrane cofactor protein (MCP). Transgenic mice were obtained that exhibit full regulation of MCP as normally observed in humans. Hearts from these mice were shown to be significantly protected from HAR caused by human serum in an in vivo experimental procedure.
Conclusions: We conclude that MCP can protect discordant xenografts from HAR caused by human serum and that transgenic mice can be used effectively as in vivo models for the study of the role of human complement regulatory molecules in xenotransplantation. 相似文献
Results: Transgenesis with a yeast artificial chromosome (YAC) was used to produce transgenic mice with the complete genomic gene of the human complement regulator membrane cofactor protein (MCP). Transgenic mice were obtained that exhibit full regulation of MCP as normally observed in humans. Hearts from these mice were shown to be significantly protected from HAR caused by human serum in an in vivo experimental procedure.
Conclusions: We conclude that MCP can protect discordant xenografts from HAR caused by human serum and that transgenic mice can be used effectively as in vivo models for the study of the role of human complement regulatory molecules in xenotransplantation. 相似文献
996.
Signal Transduction in Human T Lymphocytes 总被引:11,自引:0,他引:11
997.
Aspartylglucosaminuria in the United States 总被引:2,自引:0,他引:2
Stefan Hreidarsson George H. Momas David L. Valle Roger E. Stevenson Harold Taylor Joseph McCarty Steven B. Coker William R. Green 《Clinical genetics》1983,23(6):427-435
Aspartylglucosaminuria (AGU) was diagnosed in two unrelated males with progressive mental retardation, coarse facies and skeletal abnormalities. Until now, this disorder has been described in predominantly Finnish populations with only one previous case reported in the U.S. We conclude that AGU may be more common in nowFinnish populations than the number of reported cases would indicate and should be included in the differential diagnosis in patients with suspected lysosomal storage disorders regardless of their geographical or ethnic backgrounds. 相似文献
998.
Cerebral lateralization in the voluntary increase of heart rate was investigated in a biofeedback experiment involving 20 right-handed female subjects randomly assigned to one of two groups: right or left ear input of stimulus and biofeedback information. The stimulus was a 1000 Hz tone which signalled the start and duration of 30 20-sec training trials. Feedback was a click presented every time an interbeat interval was shorter than a criterion established through a shaping schedule. A monetary bonus provided additional reinforcement at the end of each trial. Subjects given right ear feedback increased their heart rate significantly more than subjects given left ear feedback. The largest difference between the group means (7 bpm) was recorded after the first 20 training trials. The results are discussed in terms of hemispheric perceptual and functional differences. 相似文献
999.
On the classification of the acrocephalosyndactyly syndromes 总被引:2,自引:0,他引:2
This report describes a family in which two different types of acrocephalosyndactyly (ACS) were clinically identified. The proband presented with the classic stigmata of Pfeiffer syndrome, while her cousin was considered to be a typical case of Apert syndrome. Seven other family members also have unusually shaped heads and the facial appearance reminiscent of Crouzon disease.
Observations made in this family and from previous reports in the literature, we feel there is substantial reason to re-evaluate the ACS classification and to consider that the Apert and Pfeiffer types of ACS may be one and the same. 相似文献
Observations made in this family and from previous reports in the literature, we feel there is substantial reason to re-evaluate the ACS classification and to consider that the Apert and Pfeiffer types of ACS may be one and the same. 相似文献
1000.
Modulating parameters of excitability during and after transcranial direct current stimulation of the human motor cortex 总被引:2,自引:1,他引:2
Michael A. Nitsche Antje Seeber Kai Frommann Cornelia Carmen Klein Christian Rochford Maren S. Nitsche Kristina Fricke David Liebetanz Nicolas Lang rea Antal Walter Paulus Frithjof Tergau 《The Journal of physiology》2005,568(1):291-303
Weak transcranial direct current stimulation (tDCS) of the human motor cortex results in excitability shifts which occur during and after stimulation. These excitability shifts are polarity-specific with anodal tDCS enhancing excitability, and cathodal reducing it. To explore the origin of this excitability modulation in more detail, we measured the input–output curve and motor thresholds as global parameters of cortico-spinal excitability, and determined intracortical inhibition and facilitation, as well as facilitatory indirect wave (I-wave) interactions. Measurements were performed during short-term tDCS, which elicits no after-effects, and during other tDCS protocols which do elicit short- and long-lasting after-effects. Resting and active motor thresholds remained stable during and after tDCS. The slope of the input–output curve was increased by anodal tDCS and decreased by cathodal tDCS. Anodal tDCS of the primary motor cortex reduced intracortical inhibition and enhanced facilitation after tDCS but not during tDCS. Cathodal tDCS reduced facilitation during, and additionally increased inhibition after its administration. During tDCS, I-wave facilitation was not influenced but, for the after-effects, anodal tDCS increased I-wave facilitation, while cathodal tDCS had only minor effects. These results suggest that the effect of tDCS on cortico-spinal excitability during a short period of stimulation (which does not induce after-effects) primarily depends on subthreshold resting membrane potential changes, which are able to modulate the input-output curve, but not motor thresholds. In contrast, the after-effects of tDCS are due to shifts in intracortical inhibition and facilitation, and at least partly also to facilitatory I-wave interaction, which is controlled by synaptic activity. 相似文献