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To study the effect of controlled heavy drinking of 60 g ethanol/day for 3 weeks on carbohydrate-deficient transferrin (CDT), a commercial double antibody kit (CDTect™) was used. By the end of the third drinking week, a statistically significant increase in the mean CDT level was observed. When compared to AST and γ-glutamyltransferase, CDT was a more informative marker. However, only in 2 of the 10 volunteers did CDT exceed the upper normal level (20 units/liter) recommended by the manufacturer. This indicates that the sensitivity of CDT to detect heavy drinking is lower than that previously reported. The higher accuracy has in general been obtained in studies comparing healthy controls with a low alcohol consumption to alcoholics with an alcohol consumption higher than that used in the present experiment. Our results suggest that it remains to be established whether CDT, although better than AST and γ-glutamyltransferase, will provide a clinically useful tool in identifying heavy drinkers in populations covering a wide range of alcohol consumption.  相似文献   
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The metabolic syndrome, which is a set of lipid and nonlipid risk factors of metabolic origin linked with insulin resistance, is believed to be associated with an elevated risk for cardiovascular disease, but few have studied this association in prospective long-term cardiovascular outcomes trials. Placebo data from the Scandinavian Simvastatin Survival Study (4S) and the Air Force/Texas Coronary Atherosclerosis Prevention Study (AFCAPS/TexCAPS) were used post hoc to estimate the long-term relative risk of major coronary events (MCEs) associated with the metabolic syndrome, after excluding diabetes mellitus. In 4S and AFCAPS/TexCAPS, respectively, placebo-treated patients with the metabolic syndrome were 1.5 (95% confidence interval 1.2 to 1.8) and 1.4 (95% confidence interval 1.04 to 1.9) times more likely to have MCEs than those without it. Of the components of the metabolic syndrome, low high-density lipoprotein levels were associated with elevated risk of MCEs in both studies, whereas high triglycerides in 4S and elevated blood pressure and obesity in AFCAPS/TexCAPS were associated with significantly increased relative risk. Patients with the metabolic syndrome showed increased risk of MCEs irrespective of their Framingham-calculated 10-year risk score category (>20% vs 相似文献   
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A placebo-controlled, double-blind crossover study was carried out in 11 non-insulin-dependent (type 2) diabetic patients to find out the effects of a hepatic enzyme inducer (phenobarbital, 100 mg/day for 2 months) on the metabolic control, plasma C-peptide, insulin, serum, and lipoprotein lipid levels. Phenobarbital induced a significant increase in hepatic antipyrine metabolizing activity, but no significant changes were found in fasting or postload blood glucose, plasma C-peptide, or insulin levels during the study. There was a significant increase in serum total cholesterol, high-density lipoprotein cholesterol, and low-density lipoprotein cholesterol, as well as in serum total and very low-density lipoprotein triglycerides, during phenobarbital treatment as compared with placebo.  相似文献   
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This is the first study describing an experimental mastitis model using transgenic cows expressing recombinant human lactoferrin (rhLf) in their milk. The aim of the study was to investigate the concentrations in milk and protective effects of bovine and recombinant human lactoferrin in experimental Escherichia coli mastitis. Experimental intramammary infection was induced in one udder quarter of seven first-lactating rhLf-transgenic cows and six normal cows, using an E. coli strain isolated from cows with clinical mastitis and known to be susceptible to Lf in vitro. Clinical signs were recorded during the experimental period, concentrations of human and bovine Lf and indicators of inflammation and bacterial counts were determined for milk, and concentrations of acute-phase proteins and tumor necrosis factor alpha were determined for sera and milk. Serum cortisol and blood hematological and biochemical parameters were also determined. Expression levels of rhLf in the milk of transgenic cows remained constant throughout the experiment (mean, 2.9 mg/ml). The high Lf concentrations in the milk of transgenic cows did not protect them from intramammary infection. All cows became infected and developed clinical mastitis. The rhLf-transgenic cows showed milder systemic signs and lower serum cortisol and haptoglobin concentrations than did controls. This may be explained by lipopolysaccharide-neutralizing and immunomodulatory effects of the high Lf concentrations in their milk. However, Lf does not seem to be a very efficient protein for genetic engineering to enhance the mastitis resistance of dairy cows.  相似文献   
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A randomized study was performed for the comparison of two copper-releasing intrauterine contraceptive devices (IUDs), the Nova-T and the Copper-T-200, simultaneously in Denmark, Finland, and Sweden. Five years' experience demonstrated that Nova-T users had a significantly lower pregnancy rate than Copper-T-200 users. The Pearl index over 5 years was 0.8 for Nova-T users and 2.0 for Copper-T users. The performance and tolerance of the Nova-T were less affected by parity and age than was the performance of the Copper-T. Infections were treated by removal of the device and with antibiotics. The cumulative rate of removals because of infections and suspected infections was below 5 with both devices over 5 years. The copper wire in the Nova-T has a silver core which prevents corrosion-induced fragmentation of the wire. Hence, the effective lifetime of this device is more than 5 years. The results indicate that the Nova-T, which is easy to insert and remove and is associated with a low pregnancy rate and a low medical termination rate, is a real improvement over other IUDs.  相似文献   
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BACKGROUND AND METHODS: Gene therapy may offer a new tool for the treatment of renal cell carcinoma (RCC). We have tested a combination of cytotoxic and antiangiogenic gene therapy for wild-type orthotopic human RCC xenografts in nude mice using intratumoral adenovirus-mediated herpes simplex virus thymidine kinase (HSV-tk) and endostatin (ES) gene therapy. In vivo magnetic resonance imaging, morphometry, immunocytochemistry, and survival were used to evaluate the treatment effect. Adenovirus-mediated marker gene transfers (GFP) were used as controls. Results: In vivo transduction efficiency, measured using GFP gene transfer, was 27+/-7%. The combination gene therapy with HSV-tk and ES adenoviruses resulted in a significant antitumor effect (P<.01) compared to single HSV-tk (n.s.) or ES (n.s.). In the survival study, all tumors with single gene therapy using HSV-tk, ES, and marker gene adenoviruses showed progression in magnetic resonance imaging. In contrast, the majority of the tumors in the combination treatment group remained dormant or were eradicated (57%). Survival of these mice equaled healthy nude mice, and was significantly prolonged (P<.0001) compared to HSV-tk (P<.028) and ES (n.s.) groups. Conclusions: It is concluded that the inhibition of angiogenesis using ES gene transfer together with the cytotoxic HSV-tk gene therapy results in a significantly improved treatment effect in RCC compared to the single gene treatments.  相似文献   
30.
Objective. Several MRI sequences were used to evaluate the 2-year postoperative appearance of asymptomatic knee with a torn anterior cruciate ligament (ACL) reconstructed with bone–patellar tendon–bone (BTB) and semitendinosus and gracilis (STG) tendon autografts. Design and patients. Two groups with successful repair of ACL tear with BTB (n=10) or STG (n=10) autografts were imaged at 1.5 T with sagittal and oblique coronal proton density-, T2-weighted and sagittal STIR sequences and plain and contrast-enhanced oblique coronal T1-weighted sequences. The appearance of the graft and periligamentous tissues was evaluated. Results. In all 20 cases, the ACL graft showed homogeneous, low signal intensity with periligamentous streaks of intermediate signal intensity on T2-weighted images. In 10 cases, localised areas of intermediate signal intensity were seen in the intra-articular segment of the graft on proton density- and T1-weighted images. The graft itself did not show enhancement in either of the two groups, but mild to moderate periligamentous enhancement was detected in 10 cases. Conclusion. The MRI appearance of ACL autograft is variable on proton density- and T1-weighted images. Periligamentous tissue showing contrast enhancement is a typical MRI finding after clinically successful ACL reconstruction. Received: 22 February 2000 Revision requested: 27 June 2000 Revision received: 21 August 2000 Accepted: 23 August 2000  相似文献   
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