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11.

Background

Oral anticoagulation is the mainstay of stroke prevention in atrial fibrillation (AF), but must be balanced against the associated bleeding risk. Several risk scores have been proposed for prediction of bleeding events in patients with AF.

Objectives

To compare the performance of contemporary clinical bleeding risk scores in 18 113 patients with AF randomized to dabigatran 110 mg, 150 mg or warfarin in the RE‐LY trial.

Methods

HAS‐BLED, ORBIT, ATRIA and HEMORR2HAGES bleeding risk scores were calculated based on clinical information at baseline. All major bleeding events were centrally adjudicated.

Results

There were 1182 (6.5%) major bleeding events during a median follow‐up of 2.0 years. For all the four schemes, high‐risk subgroups had higher risk of major bleeding (all P  < 0.001). The ORBIT score showed the best discrimination with c‐indices of 0.66, 0.66 and 0.62, respectively, for major, life‐threatening and intracranial bleeding, which were significantly better than for the HAS‐BLED score (difference in c‐indices: 0.050, 0.053 and 0.048, respectively, all P  < 0.05). The ORBIT score also showed the best calibration compared with previous data. Significant treatment interactions between the bleeding scores and the risk of major bleeding with dabigatran 150 mg BD versus warfarin were found for the ORBIT (P  = 0.0019), ATRIA (P  < 0.001) and HEMORR2HAGES (P  < 0.001) scores. HAS‐BLED score showed a nonsignificant trend for interaction (P  = 0.0607).

Conclusions

Amongst the current clinical bleeding risk scores, the ORBIT score demonstrated the best discrimination and calibration. All the scores demonstrated, to a variable extent, an interaction with bleeding risk associated with dabigatran or warfarin.
  相似文献   
12.
13.
Multiple site damage (MSD) cracks are small fatigue cracks that may accumulate at the sides of highly loaded holes in aging aircraft structures. The presence of MSD cracks can drastically reduce the residual strength of fuselage panels. In this paper, artificial neural networks (ANN) modeling is used for predicting the residual strength of aluminum panels with MSD cracks. Experimental data that include 147 unique configurations of aluminum panels with MSD cracks are used. The experimental dataset includes three different aluminum alloys (2024-T3, 2524-T3, and 7075-T6), four different test panel configurations (unstiffened, stiffened, stiffened with a broken middle stiffener, and bolted lap-joints), many different panel widths and thicknesses, and the sizes of the lead and MSD cracks. The results presented in this paper demonstrate that a single ANN model can predict the residual strength for all materials and configurations with high accuracy. Specifically, the overall mean absolute error for the ANN model predictions is 3.82%. Furthermore, the ANN model residual strength predictions are compared to those obtained using the most accurate semi-analytical and computational approaches from the literature. The ANN model predictions are found to be at the same accuracy level of these approaches, and they even outperform the other approaches for many configurations.  相似文献   
14.
Over the last decade, structural heart disease interventions have emerged as a new field in interventional cardiology. Currently, the Accreditation Council for Graduate Medical Education accredited interventional cardiology fellowship programs in the United States provide high‐quality and well established training curriculum in coronary and peripheral interventions, but training in structural interventions remains in its infancy. The current survey seeks to collect relevant information and assess the opinion of interventional cardiology program directors in ACGME‐accredited institutions that are actively involved in structural interventional training. Our study describes the actual number of structural procedures performed by interventional cardiology fellows in ACGME‐accredited programs, the form of the structural training today and the suggestions from program directors who are actively trying to integrate structural training in the interventional cardiology fellowship programs. © 2012 Wiley Periodicals, Inc.  相似文献   
15.

Background and Purpose

Stress contributes to headaches, and effective interventions for headaches routinely include relaxation training (RT) to directly reduce negative emotions and arousal. Yet, suppressing negative emotions, particularly anger, appears to augment pain, and experimental studies suggest that expressing anger may reduce pain. Therefore, we developed and tested anger awareness and expression training (AAET) on people with headaches.

Methods

Young adults with headaches (N?=?147) were randomized to AAET, RT, or a wait-list control. We assessed affect during sessions, and process and outcome variables at baseline and 4 weeks after treatment.

Results

On process measures, both interventions increased self-efficacy to manage headaches, but only AAET reduced alexithymia and increased emotional processing and assertiveness. Yet, both interventions were equally effective at improving headache outcomes relative to controls.

Conclusions

Enhancing anger awareness and expression may improve chronic headaches, although not more than RT. Researchers should study which patients are most likely to benefit from an emotional expression or emotional reduction approach to chronic pain.  相似文献   
16.

Purpose

Binding of 68Ga-PSMA-HBED-CC (68Ga-PSMA) at prostate cancer (PC) cells increases over time. A biphasic protocol may help separating benign from tumor lesions. The aim of this study was the retrospective evaluation of a diagnostic incremental value of a dual-time point (biphasic) 68Ga-PSMA-PET/CT in patients with prostate cancer.

Methods

Retrospective analysis of 35 consecutive patients (49–78 years, median 71) with newly diagnosed PC (12/35) or recurrence of PC (23/35). PET/CT (Gemini TF16, Philips) was acquired 1 h and 3 h p. i. of 140–392 MBq (300 MBq median) 68Ga-PSMA, followed by a diagnostic contrast CT. PET findings were correlated with histology or unequivocal CT findings. Semiquantitative PET data (SUVmax, SUV mean) were acquired and target-to-background-ratios (T/B-ratio) were calculated for benign and malign lesions for both time points. Size of lymph nodes (LN) on diagnostic CT was recorded. Statistical analysis was performed for assessment of significant changes of semiquantitative PET-parameters over time and for correlation of size and uptake of lymph nodes.

Results

One hundred and four lesions were evaluated. Sixty lesions were referenced by histology or unequivocal CT findings, including eight (13.3 %) histopathologically benign lymph nodes, 12 (20 %) histopathologically lymph node metastases, 12 (20 %) primary tumors, three (5 %) local recurrences, and 25 (41.7 %) bone metastases. Forty-four lesions were axillary LN with normal CT-appearance. Benign lesions had significantly lower SUVmax and T/B-ratios compared with malignant findings. Malign lesions showed a significant increase of both parameters over time compared to benign findings. There was no correlation between LN size and SUVmax. The sensitivity, specificity, the positive predictive value and negative predictive value of PET/CT regarding pelvic LN was 94 %, 99 %, 89 %, and 99.5 %, respectively.

Conclusions

In contrast to benign tissues, the uptake of proven tumor lesions increases on 68Ga-PSMA-PET/CT over time. A biphasic PET-study may lead to a better detection of tumor lesions in unequivocal findings.
  相似文献   
17.
New device for percutaneous closure of aortopulmonary collaterals.   总被引:5,自引:0,他引:5  
A 4.5-month-old infant with tetralogy of Fallot, pulmonary atresia, and multiple aortopulmonary collaterals underwent successful occlusion of the collaterals using a new device. This new plug (Amplatzer vascular plug) is a self-expandable cylindrical device made of nitinol wire mesh. The device is available in sizes from 4 to 16 mm in 2 mm increment. The device can be used in patients with aortopulmonary collaterals, pulmonary arteriovenous malformations, venovenous collaterals, shunts, coronary fistulas, and certain type of patent ductus arteriosus.  相似文献   
18.
19.
Although catheter-based intervention is generally accepted as the treatment of choice for branch pulmonary artery (PA) stenosis, there are no data directly comparing both the need for reintervention and time to reintervention in patients undergoing transcatheter stenting versus surgical arterioplasty. We compared children who underwent surgical branch pulmonary arterioplasty and branch PA stent placement between January 2008 and May 2012 at a single tertiary center. Need for reintervention and mean time to reintervention were assessed using chi-square and independent sample Student t test. Thirty-seven patients were included (surgery n = 18, stent n = 19). Mean weight at initial intervention was 11.3 ± 8.8 kg for surgical and 20.1 ± 15.5 kg for stent (p = 0.041). Intervention was performed on the left PA in 17 patients, the right PA in 12 patients, and both PAs in 8 patients. Five patients had undergone previous intervention. On mean follow-up of 807 ± 415 days, 50 % (9 of 18) of the surgery cohort and 5.3 % (1 of 19) of the stent cohort required reintervention (p = 0.002). In all but one case reintervention was catheter-based. Mean time to reintervention for the surgery cohort was 272 ± 162 days and for the single stent cohort it was 150 days. When comparable age and weight groups were analyzed, reintervention was still more common in the surgery cohort (p = 0.007). Children undergoing surgical branch pulmonary arterioplasty are more likely to require reintervention than those undergoing stent placement.  相似文献   
20.
We report on the use of the Edwards-Cribier percutaneous heart valve (PHV) in a stenotic right ventricle to pulmonary artery homograft in a 16-year old patient who underwent the Ross operation. Initially, the homograft was stented and at the same procedure, the PHV was deployed inside it. This is the first human case of the application of this valve in the pulmonary valve position.  相似文献   
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