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During 2012, Sierra Leone experienced a cholera epidemic with 22,815 reported cases and 296 deaths. We conducted a matched case-control study to assess risk factors, enrolling 49 cases and 98 controls. Stool specimens were analyzed by culture, polymerase chain reaction (PCR), and pulsed-field gel electrophoresis (PFGE). Conditional logistic regression found that consuming unsafe water (matched odds ratio [mOR]: 3.4; 95% confidence interval [CI]: 1.1, 11.0), street-vended water (mOR: 9.4; 95% CI: 2.0, 43.7), and crab (mOR: 3.3; 95% CI: 1.03, 10.6) were significant risk factors for cholera infection. Of 30 stool specimens, 13 (43%) showed PCR evidence of toxigenic Vibrio cholerae O1. Six specimens yielded isolates of V. cholerae O1, El Tor; PFGE identified a pattern previously observed in seven countries. We recommended ensuring the quality of improved water sources, promoting household chlorination, and educating street vendors on water handling practices.  相似文献   
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Pharmaceutical Research - A platform for determining size distribution of micron (1–100 μm) and larger (>?100 μm) aggregates of therapeutic IgG has...  相似文献   
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Oxalate/calcium oxalate toxicity is mediated through generation of reactive oxygen species in a process that partly depends upon events that induce mitochondrial damage. Mitochondrial dysfunction is an important event favoring stone formation. The objective of the present study was to investigate whether mitochondria is a target for oxalate/calcium oxalate and the plausible role of naturally occurring glycosaminoglycans from edible seaweed, fucoidan in ameliorating mitochondrial damage. Male albino rats of Wistar strain were divided into four groups and treated as follows: Group I: vehicle treated control, Group II: hyperoxaluria was induced with 0.75% ethylene glycol in drinking water for 28 days, Group III: fucoidan from F. vesiculosus (5 mg/kg b.wt, s.c) from the 8th day of the experimental period, Group IV: ethylene glycol+fucoidan treated rats. The tricarboxylic acid (TCA) cycle enzymes like succinate dehydrogenase, isocitrate dehydrogenase, malate dehydrogenase and respiratory complex enzyme activities were assessed to evaluate mitochondrial function. Oxidative stress was assessed based on the activities of antioxidant enzymes, level of reactive oxygen species, lipid peroxidation and reduced glutathione. Mitochondrial swelling was also analyzed. Ultra structural changes in renal tissue were analyzed with electron microscope. Hyperoxaluria induced a decrease in the activities of TCA cycle enzymes and respiratory complex enzymes. The oxidative stress was evident by the decrease in antioxidant enzymes, glutathione and an increase in reactive species and lipid peroxidation in mitochondria. Mitochondrial damage was evident by increased mitochondrial swelling. Administration of fucoidan, decreased reactive oxygen species, lipid peroxidation (P<0.05), mitochondrial swelling and increased the activities of antioxidant enzymes and glutathione levels (P<0.05) and normalized the activities of mitochondrial TCA cycle and respiratory complex enzymes (P<0.05). From the present study, it can be concluded that mitochondrial damage is an essential event in hyperoxaluria, and fucoidan was able to effectively prevent it and thereby the renal damage in hyperoxaluria.  相似文献   
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Proceedings of the National Academy of Sciences, India Section B: Biological Sciences - Cassia (C.) surattensis Burm. f. (Leguminosae) is a flowering plant that has been traditionally used in many...  相似文献   
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OBJECTIVES: To investigate the effect of triclosan exposure on the antimicrobial susceptibilities of numerically important dental bacteria. METHODS: A gradient plate technique was used to expose Fusobacterium nucleatum, Lactobacillus rhamnosus, Neisseria subflava, Porphyromonas gingivalis, Actinomyces naeslundii, Prevotella nigrescens, Streptococcus oralis, Streptococcus sanguis, Streptococcus mutans and Veillonella dispar repeatedly to escalating, sublethal concentrations of triclosan. Escherichia coli ATCC 8739 was included as an organism showing the triclosan resistance development trait. MIC values towards chlorhexidine, metronidazole and tetracycline were determined before and after biocide exposure. RESULTS: N. subflava, Pr. nigrescens Po. gingivalis and E. coli were highly susceptible to triclosan (MIC range 0.1-3.9 mg/L), whereas the lactobacillus and S. mutans were less susceptible (MIC range 15.6-20.8 mg/L). Triclosan exposure resulted in a highly significant ( approximately 400-fold) reduction in triclosan susceptibility (P < 0.01) for the positive control E. coli, although its MICs towards chlorhexidine, metronidazole and tetracycline were not significantly altered. Minor ( approximately two-fold) decreases in triclosan susceptibility (MIC) occurred for Pr. nigrescens and in S. sanguis and S. oralis (MBC). Mean changes in susceptibilities (MIC and MBC) of the oral species to chlorhexidine, metronidazole and tetracycline did not exceed two-fold, although chlorhexidine MBCs for S. sanguis were markedly, but transiently, increased. CONCLUSIONS: These data fail to demonstrate biologically significant drug resistance in triclosan-exposed bacteria and suggest that markedly decreased triclosan susceptibility, although confirmed for E. coli, is not a universal phenomenon. Other bacteria possibly possess more susceptible targets than FabI that are highly conserved, which may govern triclosan activity.  相似文献   
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Oxidative and nitrosative stress are known to exert various adverse effects on biological systems and this seems to be one of the major contributor of nephrotoxicity induced by cyclosporine A (CsA), which is a major clinical challenge, despite its potent immunosuppressive effect. Sulphated polysaccharides of marine origin are well known for its antioxidant properties, among its other biological applications. CsA administration (25 mg/kg body weight, orally, for 21 d) showed increased level of oxidants and xanthine oxidase activity. CsA induced nitrosative stress was evident from a marked elevation in the expression of inducible nitric oxide synthase mRNA in renal tissue and a concomitant increase in plasma nitric oxide level. Augmented levels of malondialdehyde, 8-hydroxy-2-deoxyguanosine and protein carbonyl coupled with diminished protein thiols; hallmarks of lipid peroxidation, DNA damage and protein oxidation were noted in CsA administered rats. Membrane damage was further confirmed by altered ATPase activities in the renal tissue. Simultaneous treatment with sulphated polysaccharides (5 mg/kg body weight, subcutaneously) remarkably prevented the above alterations mediated by oxidative and/or nitrosative stress during CsA induction. Hence, these findings conclude that the use of an antioxidant agent like sulphated polysaccharides could be a useful tool in reducing CsA-induced nephrotoxicity.  相似文献   
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Background: The aim of this study was to assess the effect of a cylindrical corrective lens with frosted sides on Humphrey automated perimetry performed with a translucent spectacle occluder in the contralateral eye. Methods: Ten healthy volunteers with cylindrical refractive errors of more than 1.50 DC had Humphrey visual fields (30‐2) measured with the contralateral eye occluded with either a translucent spectacle occluder or an opaque patch. The order of testing with each occluder was randomised. Additionally, visual field examination with the opaque patch was performed on three volunteer subjects with deep‐set eyes to establish the clinical significance of the frosted cylindrical lens induced artefact (CLA). The back vertex distances for the correcting lenses were measured for all tests. Results: Eight out of 10 volunteers tested with the translucent occluder demonstrated CLA, which was absent when the opaque patch was used. The presence of an artefact corresponding to the axis of the cylinder was observed, when the vertex distance was more than 15 mm. Three subjects with deep‐set eyes presented with CLA, even with the use of an opaque patch. Discussion: Cylindrical lens artefacts can occur with increasing vertex distance when using a translucent spectacle occluder instead of an opaque patch. CLA is also seen in subjects with deep‐set eyes.  相似文献   
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