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BackgroundThe data on acute kidney injury (AKI) in patients without chronic kidney disease (CKD) after transcatheter aortic valve replacement (TAVR) are limited. The study sought to compare the incidence of AKI and its impact on 5-year mortality after TAVR and surgical aortic valve replacement (SAVR) in patients without CKD.MethodsThis registry included data from 6463 consecutive patients who underwent TAVR or SAVR. CKD was defined as estimated glomerular filtration rate <60 mL/min/1.73 m2. AKI was defined according to the Kidney Disease Improving Global Outcomes criteria. For sensitivity analysis, propensity-score matching between TAVR and SAVR was performed.ResultsThe study included 4555 consecutive patients (TAVR, n = 1215 and SAVR, n = 3340) without CKD. Propensity-score matching identified 542 pairs. Patients who underwent TAVR had a significantly lower incidence of AKI in comparison to those who underwent SAVR (unmatched 4.7% vs 16.4%, P < 0.001, multivariable analysis: odds ratio, 0.29, 95% confidence interval [CI], 0.20-0.41; matched 5.9% vs 19.0%, P < 0.001). Patients with AKI had significantly increased 5-year mortality compared with those without AKI (unmatched 36.0% vs 19.1%, log-rank P < 0.001; matched 36.3% vs 24.0%, log-rank P < 0.001). The adjusted hazard ratios for 5-year mortality were 1.58 (95% CI, 1.20-2.08) for AKI grade 1, 3.27 (95% CI, 2.09-5.06) for grade 2, and 4.82 (95% CI, 2.93-8.04) for grade 3.ConclusionsTAVR in patients without CKD was associated with a significantly less frequent incidence of AKI compared with SAVR. AKI significantly increased the risk of 5-year mortality after either TAVR or SAVR, and increasing severity of AKI was incrementally associated with 5-year mortality.  相似文献   
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We evaluated the relationship between the variability in the left ventricular mass index (LVMI) and different hemodynamic factors. LVMI was associated with blood pressure and, in one subgroup, strongly to arterial pulse wave velocity (PWV). High physical activity was connected to increased LVMI, and a combination of low stroke index (SI) and high heart rate (HR) to decreased LVMI.  相似文献   
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We have assessed the angiographic features of a group of 37 patients given oral dipyridamole and 37 patients given matching placebo. Both groups represented severe coronary arterial disease and were studied prior to bypass surgery. Six patients (16%) had angina and 13 patients (35%) had electrocardiographic changes after dipyridamole. All the patients in the control group were nonresponders. In the group given dipyridamole the patients responding with angina had significantly more compromised collaterals than the patients without chest pain (P = 0.021). The same applied to the patients with electrocardiographic changes versus those with no electrocardiographic changes (P = 0.034). No differences between responders and nonresponders could be found in terms of the severity of coronary arterial disease, severity of anginal symptoms, exercise tolerance, antianginal medication, number of past myocardial infarctions, and left ventricular ejection fraction. In conclusion, the data strongly suggest that ischaemic responses to dipyridamole originate from myocardial steal accentuated by compromised flow in collateral vessels.  相似文献   
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Laminin has been proposed to influence the function of human adrenal cortex. We have studied the distribution of laminin (Ln) chains using immunofluorescence in human fetal and adult adrenal cortex. In the fetal gland Ln alpha2- and alpha5-chains were weakly expressed in the definitive zone, whereas Ln alpha4-, beta1-, and gamma1-chains occurred around vessels. In the adult gland, Ln alpha2-, alpha5-, and gamma1-chains were found in epithelial basement membranes (BM) in all cortical zones, Ln alpha4-chain in vessels, Ln beta1-chain in outer zone, and Ln beta2-chain in the two inner zones of the cortex, respectively. Among the integrins in adult gland, integrin alpha(3)-subunit was confined to basal surfaces of cortical cells, alpha(6) to vessels, alpha(1) to the stroma, and alpha(2) diffusely to epithelial cells. Lutheran glycoprotein and dystroglycan occurred in the fetal gland diffusely in the definitive zone and throughout the epithelium in the adult. The isoform composition of BM of the adult adrenal gland is distinct, with Ln-2 and -10 in BM of the outer zone and Ln-4 and -11 in BM of the two inner zones. The results suggest that integrin alpha(3)beta(1) and Lutheran are candidate receptors for Ln-10 and -11, whereas dystroglycan probably binds Ln-2 and -4.  相似文献   
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During the years 1977 to 1983, 1,458 pacemakers were implanted or reimplanted in our clinic. Seventy-nine patients were treated during the same period for pacemaker system infections. The time interval between the preceding surgical maneuver and the manifest infection was 11.9 +/- 10.2 months in the catheter fistulas and 12.2 +/- 11.5 months in the pacemaker pocket infections. Forty-one of 79 infections (52%) occurred following the first generator implantation. In 33/43 (76.7%) patients with partial pacemaker system removal, recurrent infection occurred 19.6 +/- 17.2 months later. The infection was treated with similar surgical maneuvers resulting in subsequent infections in 9 patients after 9.8 +/- 7.2 months. In the patients with total pacemaker system removal infection developed in 2/25 (8%). The infection resulted in septicemia in 9 patients. Major surgical intervention was necessary for removal of the infected endocardial electrode in 7 patients. According to our experience there are no grounds for partial removal of the pacemaker system if infection occurs. The primary results may be satisfactory but re-infection will appear in the majority of the patients after a period of several months.  相似文献   
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AIMS: Peroxisome proliferator-activated receptor gamma (PPARgamma) activators have recently been identified as regulators of cellular proliferation, inflammatory responses and lipid and glucose metabolism. These agents prevent coronary arteriosclerosis and improve left ventricular remodelling and function in heart failure after myocardial infarction. Improvement in myocardial metabolic state may be one of the mechanisms behind these findings. The aim of this study was to investigate the effects of rosiglitazone on myocardial glucose uptake in patients with Type 2 diabetes. Placebo and metformin were used as control treatments. METHODS: Forty-four patients were randomized to treatment with rosiglitazone (4 mg b.i.d.), metformin (1 g b.i.d.) or placebo in a 26-week double-blinded trial. Myocardial glucose uptake was measured using [(18)F]-2-fluoro-2-deoxy-D-glucose ([(18)F]FDG) and positron emission tomography (PET) during euglycaemic hyperinsulinaemia before and after the treatment. RESULTS: Rosiglitazone increased insulin-stimulated myocardial glucose uptake by 38% (from 38.7 +/- 3.4 to 53.3 +/- 3.6 micromol 100 g(-1) min(-1), P = 0.004) and whole body glucose uptake by 36% (P = 0.01), while metformin treatment had no significant effect on myocardial (40.5 +/- 3.5 vs. 36.6 +/- 5.2, NS) or whole body glucose uptake. Myocardial work as determined by the rate-pressure-product was similar between the groups. Neither treatment had any significant effect on fasting serum free fatty acids (FFA) but the FFA levels during hyperinsulinaemia were more suppressed in the rosiglitazone group (-47%, P = 0.02). Myocardial glucose uptake correlated inversely to FFA concentrations both before (r =-0.54, P = 0.002) and after (r = -0.43, P = 0.01) the treatment period in the pooled data. Furthermore, the increase in myocardial glucose uptake correlated inversely with interleukin-6 (IL-6) concentrations (r = -0.58, P = 0.03). CONCLUSIONS: In addition to the improvement in whole body insulin sensitivity, rosiglitazone treatment enhances insulin stimulated myocardial glucose uptake in patients with Type 2 diabetes, most probably due to its suppression of the serum FFAs.  相似文献   
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Aims/hypothesis The aim of this study was to investigate the effects of lifestyle intervention on the levels of plasminogen activator inhibitor (PAI-1) and fibrinogen in subjects participating in the Finnish Diabetes Prevention Study (DPS).Methods In five DPS centres, 321 subjects with impaired glucose tolerance (intervention group, n=163; control group, n=158) had their PAI-1 and fibrinogen levels measured at baseline and at the 1-year follow-up. Additional 3-year follow-up assessments were carried out in a sample of 97 subjects in one of the DPS centres (Turku). The intervention programme included an intensive lifestyle intervention aiming at weight reduction, healthy diet and increased physical activity.Results During the first intervention year, PAI-1 decreased by 31% in the intervention group but showed no change in the control group (p<0.0001). In the Turku subgroup, the decrease in PAI-1 persisted throughout the 3-year follow-up. Changes in PAI-1 were associated with the number of lifestyle changes made during the first year (p=0.008). Weight reduction was the most important factor explaining the decrease in PAI-1. Changes in fibrinogen levels did not differ between the groups.Conclusions/interpretation In addition to the previously reported reduction in the risk of type 2 diabetes in DPS participants with impaired glucose tolerance, the intensive dietary and exercise intervention had beneficial long-term effects on fibrinolysis as indicated by the reduced levels of PAI-1. These results suggest that elevated PAI-1 levels in obese subjects with impaired glucose tolerance are mostly reversible by lifestyle changes, especially those geared to weight reduction.  相似文献   
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