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The selection and implementation of a plan for maxillary surgery is of the utmost importance in achieving the desired outcome for the patient undergoing two-jaw orthognathic surgery. Some splint-based and splintless methods, accompanied by computer-assisted techniques, are helpful in improving surgical plan implementation. However, randomized controlled trials focused on this procedure are lacking. This study included 61 patients who underwent bimaxillary surgeries. The patients were randomly assigned to a conventional resin occlusal splint (CROS) group, a digital occlusal splint (DOS) group, or a digital templates (DT) group, in a 1:1:1 ratio. The mean linear distance between the planned and actual postoperative positions of eight selected points on the surfaces of the maxillary teeth was selected as the outcome measure. The distance was significantly smaller in the DT group (1.17 ± 0.66 mm) when compared to both the CROS group (2.55 ± 0.95 mm, P < 0.05) and DOS group (2.15 ± 1.12 mm, P < 0.05). However, the difference between the CROS group and DOS group was not statistically significant. These findings indicate that using digital templates results in the best performance in transferring the surgical plan to the operation environment as compared to the other two types of splints. This suggests that the application of digital templates could provide a reliable treatment option.  相似文献   
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PurposeTo evaluate the safety and efficacy of balloon pulmonary angioplasty (BPA) for nonoperable chronic thromboembolic pulmonary hypertension (CTEPH) patients during the initial experience of a single center.MethodsA total of 18 CTEPH patients (5 with residual pulmonary hypertension after pulmonary endarterectomy) were treated with BPA during the period 2014–2018 and were retrospectively reviewed. Mean age was 61 ± 19 years; 55% were female; mean pulmonary artery pressure was 44 ± 12 mmHg; cardiac output was 4.3 ± 1.0 l/min; and pulmonary vascular resistance was 8.4 ± 3.6 WU. Patients were evaluated by New York Heart Association functional class, 6-minute walk distance, N-terminal pro b-type natriuretic peptide, echocardiography, right heart catheterization, and before and after completions of BPA.ResultsA total of 91 procedures were performed, with a median number of 4 BPA sessions per patient (range, 2–8). There were no deaths or major complications requiring extracorporeal support or (non)invasive ventilation. The most common complication was self-limiting hemoptysis (3%). According to Society of Interventional Radiology classification, 4 mild, 4 moderate, and 1 severe adverse events were noted. Invasive hemodynamics significantly improved, with a cardiac index increase of 15% (P = .0333), decrease of mean pulmonary artery pressure of 30% (P = .0013), and decrease of pulmonary vascular resistance of 45% (P = .0048). Stroke volume index (P = .0171) and pulmonary arterial compliance (P = .0004) were also significantly enhanced.ConclusionsBPA significantly improves cardiopulmonary hemodynamics with an acceptable safety profile. Further studies assessing the long-term efficacy of BPA are required.  相似文献   
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The purpose of this study was to describe a newly developed procedure for temporary mandibulotomy and subsequent osteosynthesis. Clinical outcomes were evaluated, including complications and the impact on postoperative treatment, particularly postoperative radiotherapy. Twenty-four patients underwent temporary mandibulotomies for the surgical resection of malignancies located in the posterior oral or oropharyngeal region. All were treated with postoperative radiotherapy. An angulated median mandibulotomy was followed by osteosynthesis with three anchor screws directed towards the inferior aspect of the mandible. Anchor screws are modified conventional lag screws that include an additional biconcave washer. This modification prevents the screw heads from cracking into the cancellous bone during tightening, improving their biomechanical qualities considerably. Insertion of screws at any angle to the bony surface therefore becomes possible, which is a precondition for this technique. Minor complications occurred in two patients in the early postoperative period. However, complications causing bony non-union, leading to postponed postoperative radiotherapy were not noted in this cohort.  相似文献   
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Severe skeletal open bite associated with posterior vertical maxillary excess and mandibular deformity is considered a difficult problem in orthodontic and surgical treatment. This study used a navigation system for the correction of severe skeletal open bite in order to accurately transfer the virtual plan to the actual operation and achieve precise rigid internal fixation in bimaxillary osteotomies of the jaws. Twelve patients with a severe skeletal open bite associated with vertical maxillary excess and mandibular deformity were recruited. All patients underwent Le Fort I osteotomy and bilateral sagittal split ramus osteotomy with the guidance of this navigation system. Computed tomography and cephalometric examinations were performed to evaluate the correction of the deformity. Deviations between the simulated plan and actual postoperative outcome were measured to determine the precision of the surgery. Satisfactory and stable results were achieved in all patients postoperatively, without complications or relapse during follow-up. Photographs and cephalometric evaluations showed that the facial profile and occlusion were improved. Assessment of the deviations between the simulated plan and actual postoperative outcome showed that the navigation system can precisely transfer the virtual plan to the actual operation. The results suggest that the navigation system can accurately transfer the virtual plan to the actual operation during bimaxillary jaw osteotomies, without relapse, in patients with a severe skeletal open bite.  相似文献   
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ObjectivesThe authors hypothesized that quantitative computed tomography (QCT) imaging would reveal subclinical increases in lung congestion in patients with heart failure and preserved ejection fraction (HFpEF) and that this would be related to pulmonary vascular hemodynamic abnormalities.BackgroundGross evidence of lung congestion on physical examination, laboratory tests, and radiography is typically absent among compensated ambulatory patients with HFpEF. However, pulmonary gas transfer abnormalities are commonly observed and associated with poor outcomes.MethodsPatients referred for invasive hemodynamic exercise testing who had undergone chest computed tomography imaging within 1 month were identified (N = 137). A novel artificial intelligence QCT algorithm was used to measure pulmonary fluid content.ResultsCompared with control subjects with noncardiac dyspnea, patients with HFpEF displayed increased mean lung density (–758 HU [–793, –709 HU] vs –787 HU [–828, –747 HU]; P = 0.002) and a higher ratio of extravascular lung water to total lung volume (EVLWV/TLV) (1.25 [0.80, 1.76] vs 0.66 [0.01, 1.03]; P < 0.0001) by QCT imaging, indicating greater lung congestion. EVLWV/TLV was directly correlated with pulmonary vascular pressures at rest, with stronger correlations observed during exercise. Patients with increasing tertiles of EVLWV/TLV demonstrated higher mean pulmonary artery pressures at rest (34 ± 11 mm Hg vs 39 ± 14 mm Hg vs 45 ± 17 mm Hg; P = 0.0003) and during exercise (55 ± 17 mm Hg vs 59 ± 17 mm Hg vs 69 ± 22 mm Hg; P = 0.0003).ConclusionsQCT imaging identifies subclinical lung congestion in HFpEF that is not clinically apparent but is related to abnormalities in pulmonary vascular hemodynamics. These data provide new insight into the long-term effects of altered hemodynamics on pulmonary structure and function in HFpEF.  相似文献   
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膝关节因外伤或退变等因素发生内翻畸形时,长期异常的负重载荷会加速内侧间室关节软骨的退变,引发膝关节骨性关节炎。胫骨髁外翻截骨术(tibial condylar valgus osteotomy,TCVO)对胫骨内侧平台塌陷具有“跷跷板”效应的膝关节内翻畸形具有很好的治疗效果。本文报道1例经TCVO联合关节镜下清理术治疗Schatzker Ⅳ型胫骨内侧平台陈旧性骨折伴内翻畸形病例。  相似文献   
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