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Effect of N-acetylcysteine on blood and tissue lipid peroxidation in lipopolysaccharide-induced obstructive jaundice. 总被引:2,自引:0,他引:2
Mehmet Caglikulekci Musa Dirlik Cengiz Pata Marylene Plasse Lulufer Tamer Zekai Ogetman Bahadir Ercan 《Journal of investigative surgery》2006,19(3):175-184
In obstructive jaundice, free radical production is increased and antioxidative activity is reduced. N-Acetylcysteine (NAC) has a beneficial effect with anti-inflammatory and antioxidant activity, acting as a free radical scavenger. NAC inhibits inducible nitric oxide synthase, suppresses cytokine expression/release, and inhibits adhesion molecule expression and nuclear factor kappa B. The aim of this study was to investigate the effects of NAC on liver/renal tissue and serum lipid peroxidation in lipopolysaccharide (LPS)-induced obstructive jaundice. We randomized 60 rats into 6 groups: group 1, Sham; group 2, obstructive jaundice (OJ) induced after bile-duct ligation; group 3, OJ + NAC (100 mg kg- 1 subcutaneously); group 4, OJ + LPS (10 mg kg-1); group 5, OJ + NAC + LPS; and group 6, OJ + LPS + NAC. For each group, the biochemical markers of lipid peroxidation and the antioxidant products were measured in serum and liver/renal tissue after sacrifice. Almost all lipid peroxidation products levels were increased and antioxidant products levels were decreased in groups who received LPS (groups 4, 5, and 6), but the effect was less remarkable when NAC was administered before LPS (group 5). The same trend was seen for groups with OJ +/- LPS who did not received NAC or received it after induced toxemia (groups 2, 4, and 6) as compared to groups 1 and 3. Moreover, in the case of OJ + LPS, rats treated with NAC before LPS (group 5) had lower lipid peroxidation products levels and higher antioxidant products levels as compared to those who did not received NAC (group 4). This phenomenon was not reproducible with NAC administered after LPS (group 6). Thus, results of this study showed that NAC prevents the deleterious effects of LPS in obstructive jaundice by reducing lipid peroxidation in serum and liver/renal tissue if administered before LPS. Nonetheless, NAC failed to prevent the lipid peroxidation in the case of established endotoxemia in obstructive jaundice. 相似文献
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J Peltzer L Colman J Cebrian H Musa M Peckham A Keller 《Developmental dynamics》2008,237(5):1412-1423
We have investigated whether the phenotype of myogenic clones derived from satellite cells of different muscles from the transgenic immortomouse depended on muscle type origin. Clones derived from neonatal, or 6- to 12-week-old fast and slow muscles, were analyzed for myosin and enolase isoforms as phenotypic markers. All clones derived from slow-oxidative muscles differentiated into myotubes with a preferentially slow contractile phenotype, whereas some clones derived from rapid-glycolytic or neonatal muscles expressed both fast and slow myosin isoforms. Thus, muscle origin appears to bias myosin isoform expression in myotubes. The neonatal clone (WTt) was cultivated in various medium and substrate conditions, allowing us to determine optimized conditions for their differentiation. Matrigel allowed expressions of adult myosin isoforms, and an isozymic switch from embryonic alpha- toward muscle-specific beta-enolase, never previously observed in vitro. These cells will be a useful model for in vitro studies of muscle fiber maturation and plasticity. 相似文献
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Hala U Gali-Muhtasib Makhluf J Haddadin Musa Z Nazer Nicole M Sodir Samar W Maalouf 《Medical oncology (Northwood, London, England)》1998,15(4):262-269
2-benzoyl-3-phenylquinoxaline 1,4-dioxide (BPQ) and other substituted quinoxaline 1,4-dioxides (QdO) were tested for their
ability to inhibit the stimulations of ornithine decarboxylase (ODC) enzyme activity and DNA synthesis, two biochemical markers
linked to skin tumour promotion by ultraviolet B (UVB) radiation. Topical application of BPQ on the dorsal skin of hairless
mice was found to inhibit in a dose-dependent manner UVB-induced ODC activity and DNA synthesis. When applied 20 min before
UVB radiation, a dose of 17 mg BPQ applied in 0.4 ml of vehicle inhibited UVB-induced ODC activity and DNA synthesis by 95%
and 85%, respectively. This inhibitory effect is dependent on the time of administration of BPQ relative to UVB radiation,
with a generally greater inhibition observed when this compound is applied before rather than after UVB treatment. The inhibitory
abilities of the other QdO on the ODC and DNA responses induced by UVB radiation greatly varied and appear to be dependent
on the structure of the compounds and their metabolic activation in the skin following irradiation. The remarkable effectiveness
of BPQ against the ODC and DNA markers of UVB promotion is also observed following multiple applications of this agent. These
results suggest that QdO, in particular BPQ and certain derivatives of it, may be useful in protecting the skin against UVB-induced
skin damage. 相似文献
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338 women with age ranging from 15 to 69 years in a suburban Sudanese community were randomly selected and studied. Urine sample, high vaginal swabs and blood samples were investigated for bacterial vaginosis, candidiasis, trichomoniasis, gonorrhoea, HIV and syphilis. The sensitivity and specificity of some laboratory tests were evaluated. Bacterial vaginosis was found in 17.2% of the subjects, candidiasis in 10.1%, trichomoniasis in 7.7%, gonorrhoea in 1.2%, HIV in 1.2% and syphilis in 0.9% of the subjects. The sensitivity and specificity of amine test as a criterion for diagnosing bacterial vaginosis was 58.6% and 73.2%, respectively. The respective values of clue cells in wet preparation were 43.1% and 99.6%. The vaginal discharge in women with bacterial vaginosis lacked pus cells unless associated with concurrent infection. 相似文献
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Due to its availability and affordable processing, date palm fiber (DPF) is among the natural and sustainable fibers used in cementitious composites. Furthermore, DPF is an agricultural, organic, and fibrous material that when subjected to higher temperature can easily degrade and cause reduction in strength. Therefore, the influence of elevated temperatures on the unit weight and strengths of DPF-reinforced concrete needs to be examined. Under this investigation, DPF is used in proportions of 0–3% weight of binder to produce a DPF-reinforced concrete. Silica fume was utilized as a supplemental cementitious material (SCM) in various amounts of 0%, 5%, 10%, and 15% by weight to enhance the heat resistance of the DPF-reinforced concrete. The concrete was then heated to various elevated temperatures for an hour at 200 °C, 400 °C, 600 °C, and 800 °C. After being exposed to high temperatures, the weight loss and the compressive and relative strengths were examined. The weight loss of DPF-reinforced concrete escalated with increments in temperature and DPF content. The compressive and relative strengths of the concrete improved when heated up to 400 °C, irrespective of the DPF and silica fume contents. The heat resistance of the concrete was enhanced with the replacement of up to 10% cement with silica fume when heated to a temperature up to 400 °C, where there were enhancements in compressive and relative strengths. However, at 800 °C, silica fume caused a significant decline in strength. The developed models for predicting the weight loss and the compressive and relative strengths of the DPF-reinforced concrete under high temperature using RSM have a very high degree of correlation and predictability. The models were said to have an average error of less than 6% when validated experimentally. The optimum DPF-reinforced concrete mix under high temperature was achieved by adding 1% DPF by weight of binder materials, replacing 12.14% of the cement using silica fume, and subjecting the concrete to a temperature of 317 °C. The optimization result has a very high desirability of 91.3%. 相似文献
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Taofeek Olakunle Ajiboye Musa Toyin Yakubu Adenike Temidayo Oladiji 《Pharmaceutical biology》2016,54(10):1962-1970
Context Despite the reported anticarcinogenic activity of lophirones B and C, no scientific information exists for its activity in rat hepatocytes.Objective Effect of lophirones B and C on aflatoxin B1 (AFB1)-induced oxidative stress, and DNA fragmentation in rat hepatocytes was investigated.Materials and methods Wistar rat hepatocytes were incubated with lophirones B and C (1?mg/mL) or sylimarin (1?mg/mL) in the presence or absence of AFB1. For an in vivo study, rats were orally administered with lophirones B and C, and/or AFB1 (20?μg/d) for 9 weeks.Results Lophirones B and C lowered AFB1-mediated increase in nitric oxide, superoxide anion radicals, caspase-3 and fragmented DNA. Lophirones B and C attenuated AFB1-mediated decrease in superoxide dismutase, catalase, glutathione peroxidase, glutathione reductase, and reduced glutathione. Also, lophirones B and C attenuated AFB1-mediated increase in conjugated dienes, lipid hydroperoxides and malondialdehyde in rat hepatocytes. Furthermore, AFB1-mediated alterations in alkaline phosphatase, alanine aminotransferase, aspartate aminotransferase, albumin, total bilirubin and globulin in rat serum were significantly annulled in lophirones B and C-treated rats.Conclusion This study revealed that lophirones B and C prevented AFB1-induced oxidative damage in rat hepatocytes. 相似文献
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