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Glucose metabolism in injured tissue: a longitudinal study 总被引:1,自引:0,他引:1
Injured tissue is characterized by increased glucose uptake and increased lactate production as compared to normal tissue. These metabolic changes have been attributed to the presence of inflammatory cells in injured tissues. To correlate these metabolic changes with changes in the inflammatory cell population at various times after injury, we studied the lambda-carrageenan hindlimb wound model in anesthetized rats. Perfusion studies demonstrated that at 3 and 5 days after injury glucose uptake was increased in injured hindlimbs, compared with hindlimbs from pair-fed control animals. At 3, 5, and 10 days after injury, lactate production from glucose was increased in injured hindlimbs, compared with hindlimbs from pair-fed control animals. These metabolic changes were not related to differences in body weight or food intake. There was no difference in glucose oxidation or in oxygen consumption in injured hindlimbs, compared with hindlimbs from pair-fed control animals. The increased glucose uptake and increased lactate production from glucose was coincident with the presence of inflammatory cells--predominantly macrophages--at the site of injury. It is suggested that the glucose metabolism in injured tissue reflects the metabolism of the inflammatory cells at the site of injury. 相似文献
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Caroline Bolton-Smith Marion E T McMurdo Colin R Paterson Patricia A Mole Julia M Harvey Steven T Fenton Celia J Prynne Gita D Mishra Martin J Shearer 《Journal of bone and mineral research》2007,22(4):509-519
Dietary supplementation with vitamin K(1), with vitamin D(3) and calcium or their combination, was examined in healthy older women during a 2-year, double-blind, placebo-controlled trial. Combined vitamin K with vitamin D plus calcium was associated with a modest but significant increase in BMC at the ultradistal radius but not at other sites in the hip or radius. INTRODUCTION: The putative beneficial role of high dietary vitamin K(1) (phylloquinone) on BMD and the possibility of interactive benefits with vitamin D were studied in a 2-year double-blind, placebo-controlled trial in healthy Scottish women > or =60 years of age. MATERIALS AND METHODS: Healthy, nonosteoporotic women (n = 244) were randomized to receive either (1) placebo, (2) 200 microg/day vitamin K(1), (3) 10 microg (400 IU) vitamin D(3) plus 1000 mg calcium/day, or (4) combined vitamins K(1) and D(3) plus calcium. Baseline and 6-month measurements included DXA bone mineral scans of the hip and wrist, markers of bone turnover, and vitamin status. Supplementation effects were tested using multivariate general linear modeling, with full adjustment for baseline and potential confounding variables. RESULTS: Significant bone mineral loss was seen only at the mid-distal radius but with no significant difference between groups. However, women who took combined vitamin K and vitamin D plus calcium showed a significant and sustained increase in both BMD and BMC at the site of the ultradistal radius. Serum status indicators responded significantly to respective supplementation with vitamins K and D. Over 2 years, serum vitamin K(1) increased by 157% (p < 0.001), the percentage of undercarboxylated osteocalcin (%GluOC) decreased by 51% (p < 0.001), serum 25-hydroxyvitamin D [25(OH)D] increased by 17% (p < 0.001), and PTH decreased by 11% (p = 0.049). CONCLUSIONS: These results provide evidence of a modest synergy in healthy older women from nutritionally relevant intakes of vitamin K(1) together with supplements of calcium plus moderate vitamin D(3) to enhance BMC at the ultradistal radius, a site consisting of principally trabecular bone. The substantial increase in gamma-carboxylation of osteocalcin by vitamin K may have long-term benefits and is potentially achievable by increased dietary intakes of vitamin K rather than by supplementation. 相似文献
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Early T-helper cell defects in HIV infection. 总被引:18,自引:0,他引:18
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Elizabeth Shearer 《分娩》1998,25(2):138-138
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Dr. phil. nat. B. Gottstein T. E. Nash M.D. Naomi I. Stocks M.D. G. M. Shearer M.D. 《Infection》1991,19(6):421-426
Summary Human peripheral blood mononuclear cells (PBMC) from two individuals experimentally and one naturally infected withGiardia lamblia responded strongly (in anin vitro lymphocyte proliferation assay) to both heterologous and homologous (parasite origin)G. lamblia antigen stimuli. Proliferative responses to specific antigens as determined by T-cell blotting were due toGiardia T-cell epitopes mostly present in antigens lower than Mr 85,000 and 31,000 in isolates PM and GS/M-H7, respectively. Additionally, Il-2 production of PBMC respective to T lymphocyte subsets under antigen stimulation were determined in one selected patient. Proliferative and lymphokine responses could be associated with CD4+ PBMC depleted of CD8+ T cells and not with PBMC depleted of CD4+ T cells. These preliminary results suggest the initiation of larger studies addressing questions of cell-mediated immune response and the role of lymphokines in human giardiasis.
Zelluläre Immunreaktion gegen Giardia lamblia beim Menschen
Zusammenfassung Periphere Blutmonozyten von zwei Personen mit einer experimentell und einer mit einer natürlich erworbenenGiardia lamblia-Infektion zeigten eine ausgeprägte lymphoproliferative Antwort nachIn-vitro-Stimulation mit Parasitenantigen, das sowohl aus homologen als auch heterologen Parasitenisolaten gewonnen worden war. Eine T-Zell-Blot- Analyse der lymphoproliferativen Immunantwort bezüglich der nach Molekulargewicht aufgetrenntenGiardia-Antigenkomponenten zeigte, daß das Spektrum derGiardia-Antigene mit T-Zell-Epitopen im Mr-Bereich von < 85'000 für das PM-1-Isolat und < 31'000 für das GS/M-H7-Isolat lagen. Bei einem der Patienten wurden Lymphozyten nach antigen-spezifischerIn-vitro-Proliferation auf ihre Lymphozytensubpopulationen und deren Fähigkeit zur Il-2-Produktion untersucht. Eine lymphoproliferative Antwort, verkoppelt mit einer Il-2-Produktion, war nur bei CD4+ Lymphozyten (nach entsprechender Eliminierung von CD8+ Lymphozyten) und nicht bei CD8+ Lymphozyten (nach entsprechender Eliminierung von CD4+ Lymphozyten) nachweisbar.相似文献
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