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991.
We report a transesophageal echocardiographic (TEE) study in an adult patient with ischemic stroke, in whom a nodular mass lesion consistent with tumor or mediastinal lymphadenopathy appeared to be interposed between the esophageal probe and the proximal descending aorta/aortic arch. Computed tomography (CT) scan of the chest revealed no pathologic lesions, only the presence of normal mediastinal lymph nodes and a rightward displaced esophagus. This unusual, but normal rightward position of the esophagus appears to have facilitated the visualization of these normal mediastinal lymph nodes on TEE. CT scan of the chest helped clarify the benign nature of these lymph nodes, which mimicked a mediastinal mass on TEE.  相似文献   
992.
BACKGROUND: Two-dimensional echocardiography (2DE) enhanced by combining with color Doppler technology has significant limitations in providing precise quantitative information, geometric assumptions to calculate chamber volume, mass, and ejection fraction. Reconstructed three-dimensional echocardiographic (3DE) systems (from multiple cross-sectional echocardiographic scans) are still cumbersome and time-consuming. Real time 3DE (RT-3DE) with shorter imaging time than with 3D reconstruction techniques can obtain qualitative and quantitative information on heart disorders. Our purpose was to investigate the feasibility and potential value of RT-3DE as a means of accurately and quantitatively estimating the size of VSD to correlate with the surgical findings. MATERIALS AND METHODS: 38 patients with VSD were examined with RT-3DE. 3D image database was postprocessed using TomTec echo 3D workstation. The results were compared with the results measured by 2 DE and surgical findings. RT-3DE produced novel views of VSD and improved quantification of the size of the defect. The sizes obtained from 3DE have equivalent correlation with surgical findings as diameter measured by 2DE (r = 0.89 vs r = 0.90). Good agreement between blinded observers was achieved by little interobserver variability. CONCLUSION: RT-3DE offers intraoperative visualization of VSD to generate a "virtual sense of depth" without extending examining time. From an LV en face projection, the positions, sizes, and shapes of VSDs can be accurately determined to permit quantitative recording of VSD dynamics. It is a potentially valuable clinical tool to provide precise imaging for surgical and catheter-based closure of difficult perimembranous and singular or multiple muscular VSD.  相似文献   
993.
This study is the first attempt to assess the prevalence of stroke and associated risk factors in Asian Indians living in the United States. The overall prevalence of stroke is 2.77% (men 3.72% and women 1.77%). Stroke was significantly associated with systemic hypertension, diabetes mellitus, coronary artery disease, end-stage renal disease, and family history of stroke and myocardial infarction.  相似文献   
994.
We present an elderly patient with ventricular septal rupture following myocardial infarction in whom live three-dimensional transthoracic echocardiography allowed comprehensive noninvasive assessment of the location, shape, and size of the septal defect, which could be clearly visualized en face from both left and right ventricular aspects.  相似文献   
995.
We describe our experience in using live/real time three-dimensional transthoracic echocardiography (3D TTE) in the assessment of five adult patients with Ebstein's anomaly. The technique was found useful in assessing the distribution and extent of tethering of each of the three leaflets of the tricuspid valve (TV) to the underlying right ventricular walls and the ventricular septum. The characteristic bubble-like appearance resulting from bulging of the non-tethered areas of the TV leaflets was also well visualized in three dimensions and their size measured. Thus, an estimate of the nontethered or free segments of all three leaflets of the TV could be obtained using this technique. This has important implications when considering these patients for surgical repair of the TV. Visualization of all three leaflets of the TV and their extent of tethering by 3D TTE also made it easier to identify the boundaries of the functioning right ventricular chamber potentially providing a more reliable assessment of its volumes and ejection fraction. Cropping of color Doppler 3D TTE data sets provided en face viewing of the TV regurgitation vena contracta permitting accurate assessment of its shape and size. This has the potential to provide a more accurate quantitative estimation of TV regurgitation severity as compared to two-dimensional color Doppler. In conclusion, live/real time 3D TTE appears useful in supplementing two-dimensional echocardiography in more comprehensively assessing the morphologic features of Ebstein's anomaly.  相似文献   
996.
We present a case of a 53-year-old woman with intractable shortness of breath that was originally ascribed to bronchiolitis obliterans organizing pneumonia. Subsequently evaluation by echocardiography and cardiac catheterization revealed that she had Lutembacher's syndrome, an uncommon combination of congenital atrial septal defect (ASD) and acquired mitral stenosis that is difficult to diagnose clinically. Our case illustrates the pitfalls and advantages of echocardiographic assessment of the mitral valve area (MVA) and the left atrial pressure (LAP). The pressure half-time method used most commonly for estimating MVA echocardiographically is inaccurate and may lead to underestimation of the severity of mitral stenosis in patients with Lutembacher's syndrome. On the other hand, the presence of ASD provides an additional method of calculating LAP, the most important determinant of symptoms in patients with mitral stenosis.  相似文献   
997.
The authors performed tissue Doppler imaging of the tricuspid annulus in patients with pulmonary hypertension to assess its correlation with invasive indices of right ventricular function. The study population consisted of 32 patients with suspected pulmonary hypertension who underwent pulsed tissue Doppler imaging of the tricuspid annulus and right heart catheterization. Peak systolic (Sa), early diastolic (Ea), and late diastolic (Aa) velocities of the lateral tricuspid annulus were measured and correlated with hemodynamic variables. Peak Sa demonstrated excellent correlation with hemodynamic variables, including cardiac index (r=0.78; P<.001), pulmonary vascular resistance (r=-0.79; P<.001), and transpulmonary gradient (r=-0.72; P<.001). Peak Sa <10 cm/s predicted cardiac index <2.0 L/min/m2 with 89% sensitivity and 87% specificity. In conclusion, tissue Doppler imaging of the tricuspid annulus is a complementary method to assess right ventricular function in pulmonary hypertensive patients.  相似文献   
998.
We describe 2 patients with significant aortic paraprosthetic regurgitation who underwent percutaneous closure where live/real time three‐dimensional transesophageal echocardiography provided incremental value over two‐dimensional transesophageal echocardiography.  相似文献   
999.
BACKGROUND:: Worsening degrees of tricuspid regurgitation (TR) have been associated with worse outcomes. We investigated the time it takes for the TR jet to attain its maximum peak (tmpTR) with measures of right ventricular (RV) function. METHODS:: Several echocardiographic variables of RV size and function and tmpTR corrected for heart rate were collected from 140 patients (mean age 57 +/- 20 years). RESULTS:: Mean RV end systolic (15 +/- 9 cm) and end diastolic (25 +/- 9 cm) areas, RV fractional area change (44 +/- 19%), maximal tricuspid annular motion (1.98 +/- 0.71 cm), pulmonary artery systolic pressure (57 +/- 33 mm Hg) and tmpTR (248 +/- 75 ms). A negative correlation was seen between tmpTR and RV fractional area change (r = -0.74; P < 0.0001) and between tmpTR and maximal tricuspid annular excursion (r = -0.69; P < 0.0001). On a multiple stepwise linear regression analysis tmpTR was better than pulmonary artery systolic pressure in predicting RV dysfunction (P < 0.001). Receiver operating characteristic curve analysis demonstrated that a tmpTR value >240 ms identified RV systolic dysfunction (sensitivity 79% and specificity 94%, areas under the curves 0.923, P = 0.0001). The longest tmpTR values were seen in patients with both RV systolic dysfunction and pulmonary hypertension (310 +/- 30 ms, P < 0.0001). CONCLUSION:: A delayed time to peak of the maximum TR jet correlates with RV dysfunction. Patients with normal RV function and no pulmonary hypertension had abnormal tmpTR values (243 +/- 57 ms) implying an underlying RV mechanical abnormality that requires further investigation.  相似文献   
1000.
Purpose: The purpose of this study was to determine if an optimal knee flexion angle existed that would minimize the risk of neurovascular injury from the passage of transtibial hardware during posterior cruciate ligament (PCL) reconstruction. Type of Study: Cadaveric. Materials and Methods: Fourteen fresh-frozen cadaveric knees were mounted in a Plexiglas apparatus that could be set at 5 different knee flexion angles (0°, 45°, 60°, 90°, and 100°) while joint distention was maintained. Each knee underwent magnetic resonance imaging in the axial and sagittal planes at each of the 5 flexion angles to determine the distance between the PCL tibial insertion and popliteal artery. Results: The mean distance, over all 5 flexion angles, between the PCL insertion and the popliteal artery in the axial plane was 7.6 mm, whereas the mean distance in the sagittal plane was 7.2 mm. There was a significant increase in distance with progressive flexion in both planes. Maximum mean distances were noted at 100° of flexion in both the axial (9.9 mm) and sagittal (9.3 mm) planes. An artificial line mimicking the path of a transtibial drill passed through the popliteal artery in 10 of 10 cases at the 0°, 45°, 60°, and 90° angles, and in 6 of 10 cases at the 100° angle. Conclusions: The results of this study suggest that increasing knee flexion reduces, but does not completely eliminate, the risk of arterial injury during arthroscopic PCL reconstruction.  相似文献   
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