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A case is reported in which a perforation of the sinus floor of the maxillary sinus occurred with extrusion of a calcium hydroxide paste during routine root canal treatment of a maxillary premolar. All clinical manifestations are described as well as the results of a follow-up evaluation.  相似文献   
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Background: We studied the correlation among cardiac magnetic resonance imaging (MRI), gallium-67 myocardial uptake, and right ventricular endomyocardial biopsy results in chronic Chagas' disease. To our knowledge, this represents the first attempt to correlate the histological findings with cardiac MRI and gallium-67 myocardial uptake for noninvasive diagnosis of inflammatory activity associated with Chagas' disease. Methods: Ten male patients with cardiomyopathy secondary to Chagas' disease were studied (mean age, 47.7 ± 7 years; congestive heart failure New York Heart Association [NYHA] functional class II [two patients], III [six patients], and IV [two patients]; and mean echocardiographic left ventricular [LV] ejection fraction [EF], 36 ± 6%). The patients underwent right ventricular endomyocardial biopsy, cardiac MRI, and gallium-67 myocardial uptake testing. The results of this group were compared with those of a control group of patients with idiopathic dilated cardiomyopathy who were matched in age (mean age, 46 ± 10 years), LV function (mean echocardiographic EF, 30 ± 4%), and NYHA classification (one patient in class II, five patients in class III, and one patient in class IV). Results: All patients with Chagas' disease showed higher signal intensity on MRI after the administration of gadolinium. The intensity of the septal signal changed from 0.90 ± 0.11 to 1.56 ± 0.19 (P < 0.001). In the control group, there was no difference in signal intensity with gadolinium (mean septal intensity, 0.94 ± 0.12 before and 0.99 ± 0.15 after; NS). On biopsy, eight chagasic patients had evident signs of myocarditis, and two patients had borderline evidence myocarditis. However, only one patient in the control group had a histological diagnosis of borderline myocarditis. Gallium-67 cardiac uptake was positive for myocardial inflammatory process in seven chagasic patients and borderline in one. On the other hand, only one patient in the control group had an uptake that was positive for inflammation, and one had a borderline result. Conclusions: In conclusion, the data from this study strongly suggest that myocarditis is frequently found in Chagas' disease. Cardiac MRI appears to be an accurate and alternative method for the diagnosis of inflammatory process associated with Chagas' disease.  相似文献   
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The effectiveness and safety of balloon-tipped, flow guided, electrodes for ventricular pacing as opposed to the fluoroscopy-guided semi-rigid bipolar electrodes have never been compared in a controlled study. A prospective study was therefore undertaken to compare both techniques in semi-elective and emergency procedures. Flow guided electrodes were inserted in 67 patients (group A) and semi-rigid electrodes in 44 patients (group B). The results of group A were judged to be superior to those of group B in four aspects: a) shorter time (6'45" vs. 13'30", p less than 0.0005); b) lower incidence of catheter displacement (13.4 vs. 32.0 percent, p less than 0.05); c) longer interval of time between implantation and catheter displacement (4.4 vs. 1.9 days, p less than 0.0005); d) lower incidence of serious ventricular arrhythmias during insertion (1.5 vs. 20.4 percent, p less than 0.005). Threshold at insertion was not significantly different (0.6 +/- 0.3 vs 0.7 +/- 0.2 milliampere). The superiority of flow-guided electrodes over fluoroscopy-guided electrodes persisted in the comparison of semielective insertions in groups A and B. We conclude that the flow-guided insertion technique is safer, more expeditious and more stable than the fluoroscopy-guided technique in semi-elective as well as in emergency insertions.  相似文献   
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Bioavailability of lead (Pb) has become an issue in quantifyingexposure of sensitive populations and, where necessary, establishingcleanup levels for contaminated soil. Immature swine were usedas a model for young children to estimate the degree to whichPb from two fully characterized composite samples from the SmugglerMountain Superfund Site in Aspen, Colorado may be bioavailableto resident children. The composite soils contained 14,200 and3870 µg Pb/g of soil. Relative and absolute enteric bioavailabilitiesof Pb in soil (oral dose groups of 75,225, and 675 µgPb/kg body wt/day) were estimated by comparison with an orallyadministered soluble Pb salt (lead acetate = PbAc2·3H2O)(dose groups of 0, 75, and 225 µg Pb/kg body wt/day) andan intravenously administered aqueous solution of Pb (100 µgPb/kg/day) from the same trihydrate salt administered dailyfor 15 days to 50 juvenile swine. The biological responses (areaunder the blood Pb concentration-time curve, and the terminalliver-, kidney-, and bone-lead concentrations) produced by Pbfrom PbAc2·3H2O and lead-contaminated soils were determined.This study revealed Pb from soil containing 14,200 µgPb/g of soil had a bioavailability relative to Pb from PbAc(RBA), ranging from 56% based on the area under the blood leadconcentration-time curve (AUC) versus dose, to 86% based oncalculations from liver- Pb loading versus dose. Similarly,Pb from soil containing 3870 µg Pb/g of soil had an RBAranging from 58% based on the AUC versus dose, to 74% basedon calculations from liver- and kidney- Pb loading versus dose.Bioavailability of Pb in soils may be more or less than EPA'sdefault RBA of 60%, therefore, measuring site- specific RBAsprovides a basis for improved exposure and risk assessment.  相似文献   
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BACKGROUND: A new noninvasive vein imaging device initially developed for phlebotomy has been tested for the first time for vein treatment. This unique device captures a near infrared vein image, processes it, and projects it onto the skin using green light. OBJECTIVE: To perform the first clinical tests of the device in phlebology. MATERIALS AND METHODS: A pilot study on 23 subjects with varicose veins and telangiectasias was performed. The VeinViewer prototype (V-V-P; Luminetx Corp., Memphis, TN) was tested in five situations: diagnosing feeder veins with the V-V-P, comparison between the V-V-P and ultrasound, marking varicose veins with or without the device, phlebectomy using the V-V-P, and the use of laser and sclerotherapy guided by the V-V-P. RESULTS: One hundred percent of subjects had feeder veins identified by the V-V-P. The ultrasound machine detected fewer feeder veins than the V-V-P, and the device identified more veins than the naked eye in all subjects. The V-V-P could help in finding feeder veins during phlebectomy and in guiding laser and sclerotherapy treatments. CONCLUSION: The device could identify veins that were invisible to the naked eye and too shallow for ultrasound detection. The V-V-P may help find feeder veins and may also help various types of vein treatments.  相似文献   
80.
Background: The incidence of venous lesions following transvenous cardiac device implantation is high. Previous implantation of temporary leads ipsilateral to the permanent devices, and a depressed left ventricular ejection fraction have been associated with an increased risk of venous lesions, though the effects of preventive strategies remain controversial. This randomized trial examined the effects of warfarin in the prevention of these complications in high-risk patients.
Method: Between February 2004 and September 2007, we studied 101 adults who underwent a first cardiac device implantation, and who had a left ventricular ejection fraction ≤0.40, or a temporary pacing system ipsilateral to the permanent implant, or both. After device implantation, the patients were randomly assigned to warfarin to a target international normalized ratio of 2.0–3.5, or to placebo. Clinical and laboratory evaluations were performed regularly up to 6 months postimplant. Venous lesions were detected at 6 months by digital subtraction venography.
Results: Venous obstructions of various degrees were observed in 46 of the 92 patients (50.0%) who underwent venography. The frequency of venous obstructions was 60.4% in the placebo, versus 38.6% in the warfarin group (P = 0.018), corresponding to an absolute risk reduction of 22% (relative risk = 0.63; 95% confidence interval = 0.013–0.42).
Conclusions: Warfarin prophylaxis lowered the frequency of venous lesions after transvenous devices implantation in high-risk patients.  相似文献   
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