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11.
Senturk H Tahan V Canbakan B Uraz S Ulger Y Ozaras R Tabak F Mert A Ozbay G 《The Netherlands journal of medicine》2008,66(5):191-195
BACKGROUND: The effect of conventional interferon-based therapy of hepatitis B virus (HBV) and hepatitis C virus (HCV) dual infection is controversial. Yet, no studies have been carried out into pegylated interferon treatment for chronic HBV/HCV coinfection. We aimed to evaluate the response rate and side effects of conventional or pegylated interferon combined with ribavirin on chronic HBV/HCV coinfection therapy. METHODS: The study included 36 chronic hepatitis patients (M/F: 28/8, mean age 47+/-12 years) who were positive for HBsAg and anti-HCV. They were tested for the presence of HBV-DNA by hybridisation assay, and the samples giving negative results were retested by polymerase chain reaction (PCR). All patients were tested for HCV-RNA using PCR, and the HCV genotype was determined. RESULTS: Nineteen patients were given standard interferon either alone or in combination with ribavirin, whereas 17 were given pegylated interferon and ribavirin combination therapy. None of the patients had HBV-DNA positivity; however, all had HCV-RNA detectable by PCR. All the patients had HCV genotype 1b. The mean alanine aminotransferase and aspartate aminotransferase levels were 118+/-65 U/l and 90+/-95 U/l respectively. Five patients in each group discontinued the treatment due to side effects. Only two patients (one from each group) reached sustained virological response. CONCLUSION: Neither pegylated nor conventional interferon based regimes were effective for HBV/HCV coinfection, in which the dominant virus was HCV. Pegylated interferon and ribavirin therapy was not superior to conventional interferon based regimes in the treatment of HBV/HCV coinfection. 相似文献
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STUDY OBJECTIVE: QT dispersion (QTd) and late potentials derived from signal-averaged ECG (SAECG) have been proposed as noninvasive predictors of cardiac arrhythmias that occur in patients with COPD. In this study, we aimed to investigate QTd and SAECG in patients with COPD. DESIGN: Cross-sectional study. SETTING: Teaching chest disease hospital and cardiology center in a university hospital. PATIENTS: Thirty patients with COPD (28 men and 2 women; mean +/- SD age, 60 +/- 9 years) and 31 age- and sex-matched control subjects (28 men and 3 women; mean age, 57 +/- 7 years) were included. Measurements and results: Respiratory function tests, arterial blood gas analyses, echocardiographic examinations, rhythm Holter recordings, and heart rate variability (HRV) analyses were performed in addition to the measurements of QT intervals and SAECG. Patients with COPD had higher rate of ventricular premature beats (VPBs) as compared to control subjects (924 +/- 493 beats vs 35 +/- 23 beats, p = 0.009). Eight patients with COPD (27%) had nonsustained runs of ventricular tachycardia (VT). QTd rates were significantly increased in patients with COPD as compared to control subjects (57.7 +/- 9.9 ms vs 37.5 +/- 8.2 ms, p < 0.001). On comparing patients with COPD with and without runs of VT, patients with VT had longer QTd (67 +/- 10 ms vs 55 +/- 8 ms, p = 0.001). However no difference in any HRV and late potential parameters were found between patients with COPD with and without runs of VT. VPB rates were strongly correlated with QTd in patients with COPD (r = 0.61, p < 0.001). On SAECG analysis, patients with COPD had significantly increased total QRS duration as compared to control subjects. Nine of the 30 patients with COPD (30%) had positive late potentials. However, QTd and VPB rates were also similar between patients with COPD with and without late potentials. CONCLUSIONS: The development of ventricular arrhythmia in patients with COPD was associated with increased QTd. Increased QTd may be associated with autonomic changes seen in patients with COPD. 相似文献
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Tahan V Ozaras R Canbakan B Uzun H Aydin S Yildirim B Aytekin H Ozbay G Mert A Senturk H 《Journal of pineal research》2004,37(2):78-84
Increased deposition of the extracellular matrix components, particularly collagen, is a central phenomenon in liver fibrosis. Stellate cells, the central mediators in the pathogenesis of fibrosis are activated by free radicals, and synthesize collagen. Melatonin is a potent physiological scavenger of hydroxyl radicals. Melatonin has also been shown to be involved in the inhibitory regulation of collagen content in tissues. At present, no effective treatment of liver fibrosis is available for clinical use. We aimed to test the effects of melatonin on dimethylnitrosamine (DMN)-induced liver damage in rats. Wistar albino rats were injected with DMN intraperitoneally. Following a single dose of 40 mg/kg DMN, either saline (DMN) or 100 mg/kg daily melatonin was administered for 14 days. In other rats, physiologic saline or melatonin were injected for 14 days, following a single injection of saline as control. Hepatic fibrotic changes were evaluated biochemically by measuring tissue hydroxyproline levels and histopathogical examination. Malondialdehyde (MDA), an end product of lipid peroxidation, and glutathione (GSH) and superoxide dismutase (SOD) levels were evaluated in blood and tissue homogenates. DMN caused hepatic fibrotic changes, whereas melatonin suppressed these changes in five of 14 rats (P < 0.05). DMN administration resulted in increased hydroxyproline and MDA levels, and decreased GSH and SOD levels, whereas melatonin reversed these effects. When melatonin was administered alone, no significant changes in biochemical parameters were noted. In conclusion, the present study suggests that melatonin functions as a potent fibrosuppressant and antioxidant, and may be a therapeutic choice. 相似文献
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Tahir Karaman Sabiha Zelal Ulku Ali Ihsan Zengingul Sedat Guven Veysel Eratilla Ebru Sumer 《The journal of advanced prosthodontics》2015,7(3):257-263
PURPOSE
In this study, we aimed to evaluate the amount of marginal gap with two different substructure materials using identical margin preparations.MATERIALS AND METHODS
Twenty stainless steel models with a chamfer were prepared with a CNC device. Marginal gap measurements of the galvano copings on these stainless steel models and Co-Cr copings obtained by a laser-sintering method were made with a stereomicroscope device before and after the cementation process and surface properties were evaluated by scanning electron microscopy (SEM). A dependent t-test was used to compare the mean of the two groups for normally distributed data, and two-way variance analysis was used for more than two data sets. Pearson''s correlation analysis was also performed to assess relationships between variables.RESULTS
According to the results obtained, the marginal gap in the galvano copings before cementation was measured as, on average, 24.47 ± 5.82 µm before and 35.11 ± 6.52 µm after cementation; in the laser-sintered Co-Cr structure, it was, on average, 60.45 ± 8.87 µm before and 69.33 ± 9.03 µm after cementation. A highly significant difference (P<.001) was found in marginal gap measurements of galvano copings and a significant difference (P<.05) was found in marginal gap measurements of the laser-sintered Co-Cr copings. According to the SEM examination, surface properties of laser sintered Co-Cr copings showed rougher structure than galvano copings. The galvano copings showed a very smooth surface.CONCLUSION
Marginal gaps values of both groups before and after cementation were within the clinically acceptable level. The smallest marginal gaps occurred with the use of galvano copings. 相似文献18.
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