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61.
62.
Matthew Freedman MD Dot Steller Hamid Jafroudi Seong Ki Mun 《Journal of digital imaging》1995,8(2):67-74
Quality control (QC) of storage phosphor devices is important in assuring that the image information entered into an Image management and communication (IMAC) system is sufficient for diagnosis. QC of storage phosphor digital radiography systems is complex because of the self-corrective nature of the image-processing software used in these machines. Currently, one must produce hard copy to perform adequate QC. Inspection of images with reject analysis and inspection of cassettes and imaging plates has helped us in our QC program. For those QC tests using control limits, the appropriate settings for these limits are unknown. Starting approximations are given. Recommended tests are described. 相似文献
63.
64.
rIFN-γ-mediated growth suppression of platinum-sensitive and -resistant ovarian tumor cell lines not dependent upon arginase inhibition 总被引:1,自引:0,他引:1
Marincola FM 《Journal of translational medicine》2003,1(1):1-2
The purpose of translational research is to test, in humans, novel therapeutic strategies developed through experimentation.
Translational research should be regarded as a two-way road: Bench to Bedside and Bedside to Bench. However, Bedside to Bench
efforts have regrettably been limited because the scientific aspects are poorly understood by full time clinicians and the
difficulty of dealing with humans poorly appreciated by basic scientists. Translational research would be most useful to the
scientific community at large if journals would foster specific interest for the publication of ex vivo human observation. The review process for such work should be assigned to clinical scientists competent not only in the intricacies
of molecular or cell biology but also intimate with the reality of Internal Review Boards, ethics committees, Governmental
Regulatory Agencies and most importantly the humane aspects of dealing with sick individuals and their families. This approach
may focus both basic and clinical scientists and those struggling to fill the gap between them on the effective treatment
of diseases affecting women, men and children making translational research more than an interesting concept. 相似文献
65.
66.
J. Freedman T. Hökfelt G. Jonsson C. Post 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1986,62(1):175-178
Summary Intrathecal administration of the substance P antagonist Spantide caused marked necrotic changes of the gray matter of the spinal cord extending several segments from the injection site. Intravenous treatment with several doses of thyrotropin releasing hormone before and after Spantide injection completely prevented the necrotic lesion. 相似文献
67.
EA rosette-forming lymphoid cells in chickens: specificity of the Fc receptor and its relationship to other surface antigens.
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The receptor for erythrocyte-antibody (EA) complexes on the surface of chicken lymphoid cells was investigated using a rosette assay. The chicken EA receptor binds chicken immunoglobulin of the IgG class but not the IgM class. Binding to the EA receptor is dependent upon the Fc region of the immunoglobulin. No receptor for complement analogous to the mammalian C3b receptor was demonstrated on chicken lymphoid cells using the rosette assay. Inhibition studies utilizing immunoglobulins from several species demonstrated that chicken spleen cells do not bind mammalian immunoglobulin but may bind immunoglobulin of other avian species (turkey and duck) and a reptilian species (turtle). The chicken EA receptor is distinct from cell membrane bound immunoglobulin light chains, bursa-specific antigens and thymus-specific antigens. The receptor for EA complexes on chicken lymphoid cells is compared with the Fc receptor on mammalian lymphoid cells in the light of these observations. 相似文献
68.
Xiong W Li J Chen L Price RA Freedman G Ding M Qin L Yang J Ma CM 《Physics in medicine and biology》2004,49(10):1973-1989
Recently, intensity-modulated radiation therapy and modulated electron radiotherapy have gathered a growing interest for the treatment of breast and head and neck tumours. In this work, we carried out a study to combine electron and photon beams to achieve differential dose distributions for multiple target volumes simultaneously. A Monte Carlo based treatment planning system was investigated, which consists of a set of software tools to perform accurate dose calculation, treatment optimization, leaf sequencing and plan analysis. We compared breast treatment plans generated using this home-grown optimization and dose calculation software for different treatment techniques. Five different planning techniques have been developed for this study based on a standard photon beam whole breast treatment and an electron beam tumour bed cone down. Technique 1 includes two 6 MV tangential wedged photon beams followed by an anterior boost electron field. Technique 2 includes two 6 MV tangential intensity-modulated photon beams and the same boost electron field. Technique 3 optimizes two intensity-modulated photon beams based on a boost electron field. Technique 4 optimizes two intensity-modulated photon beams and the weight of the boost electron field. Technique 5 combines two intensity-modulated photon beams with an intensity-modulated electron field. Our results show that technique 2 can reduce hot spots both in the breast and the tumour bed compared to technique 1 (dose inhomogeneity is reduced from 34% to 28% for the target). Techniques 3, 4 and 5 can deliver a more homogeneous dose distribution to the target (with dose inhomogeneities for the target of 22%, 20% and 9%, respectively). In many cases techniques 3, 4 and 5 can reduce the dose to the lung and heart. It is concluded that combined photon and electron beam therapy may be advantageous for treating breast cancer compared to conventional treatment techniques using tangential wedged photon beams followed by a boost electron field. 相似文献
69.
Distribution of the serotonin 2C (5HT2C) receptor gene -759C/T polymorphism in patients with schizophrenia and normal controls 总被引:2,自引:0,他引:2
BACKGROUND: In patients with schizophrenia, the percentage of patients with diabetes has been found to be twice that of the normal population. The risk factors for this higher rate are unknown, although dietary, lifestyle, and genetic factors have all been suggested. Recently, a polymorphism (-759C/T) in the serotonin 2C (5HT2C) receptor promoter region has been associated with the development of diabetes in a normal control population, with the frequency of the T allele being higher in subjects without diabetes. AIM: To determine whether the distribution of the -759C/T polymorphism of the 5HT2C receptor is different among patients with schizophrenia and normal controls. METHODS: DNA from 100 patients with schizophrenia and 81 normal controls were analyzed for the 5HT2C receptor -759C/T polymorphism to determine its allelic frequencies in these two groups. RESULTS: Using a chi-squared analysis, no statistical differences in the distribution of C alleles and T alleles were found between the two groups (P=0.2931). CONCLUSIONS: Patients with schizophrenia have a higher risk for developing diabetes than the general population. We did not find a higher distribution of the -759T allele of the 5HT2C receptor in normal controls compared with in patients with schizophrenia. This suggests the higher prevalence of diabetes in schizophrenia is not due to this polymorphism. 相似文献