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991.
Executive directors of Oregon's 36 community mental health programs were surveyed in the fall of 1983 to determine the nature of psychiatric services offered and the roles played by psychiatrists. The study showed that a total of 18.2 full-time-equivalent psychiatrists were working in the community system, a mean of .5 per program, considerably below the national average. None of the responding directors were psychiatrists, and only six employed psychiatrists as medical directors. The directors valued psychiatrists most highly for their skills in educating, supervising, and consulting with staff; for their unique clinical skills; and for medication management. They considered the biggest disadvantage of employing psychiatrists to be the expense. The authors discuss factors that contribute to psychiatrists' satisfaction with work in community mental health programs and strategies for recruiting and retaining psychiatrists in the programs. 相似文献
992.
BACKGROUND: The MN human blood group antigens are complex glycopeptide antigens at the amino terminus of glycophorin A. Many different mouse monoclonal antibodies to these antigens have been produced and characterized. The construction of combinatorial immunoglobulin libraries displaying antibody Fab fragments on the surface of bacteriophage (Fab-phage) represents a novel approach for developing monoclonal reagents, for exploring the diversity of the immune response to specific antigens, and for understanding the molecular basis of the interaction of an antibody with its antigen. However, it is necessary to determine whether Fab fragments displayed on bacteriophage surfaces retain immunologic characteristics similar to the intact antibodies. STUDY DESIGN AND METHODS: Fab-phage were constructed from three anti-N (AH7, N61, and N92) and two anti-M (425/2B and M2A1) murine hybridomas. The Fab-phage and parental hybridomas were compared by enzyme-linked immunosorbent assay, Western blotting, and flow cytometry. RESULTS: In each case, the Fab-phage and its parental hybridoma antibody had similar immunologic characteristics. In particular, their dependence on the pH of the buffer and on sialylation of the target antigen was similar. CONCLUSION: These results suggest that Fab-phage may provide novel reagents with applications in immunohematology and may be useful in the study of the immune response to human blood group antigens. 相似文献
993.
用小鼠肝细胞核制备和肝微粒体制备,研究了化合物SY-640对致癌剂苯并芘(BP)损伤肝细胞核的保护作用及与P-450的关系。结果表明,SY-640可显著抑制3H-BP与小鼠肝细胞核的DNA共价结合。SY-640连续po 3 d,可显著诱导小鼠肝微粒体细胞色素P-450含量及氨基比林脱甲基酶活性;给药1次2h内却只抑制氨基比林脱甲基酶活性。体外温孵实验表明,SY-640对小鼠肝微粒体氨基比林脱甲基酶活性也具有明显的抑制作用。差示光谱分析表明,SY-640可与细胞色素P-450形成络合物。提示该化合物对肝微粒体细胞色素P-450酶系的影响与其对化学致癌剂BP所致肝细胞毒性的保护作用有关。 相似文献
994.
Exacerbation of Pneumocystis carinii pneumonia in immunodeficient (scid) mice by concurrent infection with a pneumovirus. 下载免费PDF全文
scid mice naturally infected with Pneumocystis carinii and inoculated with a normally apathogenic pneumovirus had significantly higher P. carinii cyst counts and developed significantly more severe P. carinii-related disease than did sham-inoculated, P. carinii-infected scid mice. P. carinii-free, virus-infected scid mice survived for 2 months despite high pulmonary virus titers. These results show that a respiratory virus infection can exacerbate P. carinii disease in an immunocompromised-rodent model. 相似文献
995.
J J Payne-James S K Rana M J Bray D A McSwiggan D B Silk 《JPEN. Journal of parenteral and enteral nutrition》1992,16(4):369-373
A prospective clinical study in three phases was performed to determine whether it was possible that enteral diet containers could become contaminated as a result of endogenous organisms ascending retrogradely from the enteral feeding tube via the giving set, and if this did occur whether the incidence could be altered by modifying enteral delivery systems. Each phase observed patients on enteral feeding over a 48-hour study period (phase I, n = 18; phase II, n = 17; phase III, n = 18). Each patient was prescribed an enteral diet of 2 L/24 h administered by continuous pump infusion from a closed 1-L sterile diet container. Four containers were used for each patient, and one giving set was used in the 48-hour period. Diet samples were taken at 12-hour intervals: two from the giving set before and after flushing with residual diet, and one from the diet container. Phases differed only in the design of the giving set: phase I had no drip chamber, phase II had a drip chamber, phase III had a drip chamber and an anti-reflux ball valve at the distal end. Both phase I and III had greater numbers of giving set samples colonized at 24, 36, and 48 hours. In phase I, 3 of 14 sterile diet containers were colonized with greater than 10(4) colony-forming organisms/mL of diet at 48 hours. Only phase II had no organisms contaminating the containers at 48 hours. We conclude that the retrograde spread of organisms from patient to sterile diet container does occur in clinical practice, and that a drip chamber in the giving set may prevent the problem.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
996.
A neuron-specific enhancer of the Drosophila dopa decarboxylase gene 总被引:10,自引:0,他引:10
At least two cis-regulatory elements are necessary for correct neuron-specific expression of the Drosophila melanogaster dopa decarboxylase gene, Ddc. In addition to a previously described proximal element located approximately 60 bp upstream of the mRNA start site, we have now characterized a distal approximately 600-bp DNA fragment, extending from -1019 to -1623 bp, which possesses enhancer-like properties and is essential for normal neuron-specific expression. Immunofluorescent labeling of neurons expressing deleted Ddc genes indicates that this region contains both general neuronal regulatory elements and cell-specific elements that selectively affect Ddc expression in either dopaminergic or serotonergic neurons. These selective effects can be correlated with the removal of sequence elements that are protected from DNase digestion by factors present in embryonic nuclear extracts. Several of these elements are also homologous to sequences located upstream of the evolutionarily diverged Ddc gene of Drosophila virilis. These results suggest that the neuron-specific expression of Ddc results from the combined action of several factors binding within this distal enhancer region. 相似文献
997.
G A Bray 《The Journal of nutrition》1991,121(8):1146-1162
The mechanisms underlying different types of obesity have been gradually clarified. Animal models with hypothalamic, genetic or dietary obesity have been examined with a feedback model. Four common final pathways are involved in this model. One of these final common pathways is the sympathetic nervous system. Most Obesities kNown Are Low In Sympathetic Activity states the MONA LISA Hypothesis. A second common pathway is the endocrine system involving adrenal glucocorticosteroids. The third common pathway is hyperphagia. Although not essential for most obesities, hyperphagia may be essential in animals with injury to the hypothalamic paraventricular nucleus. The final pathway is reduced physical activity. The tonic activity of these systems and their response to changes in the diet affect nutrient partitioning between fat and protein. This framework has been used to review genetic obesity, hypothalamic obesity and dietary obesity. 相似文献
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