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Left atrial appendage (LAA) contractile dysfunction is associated with thrombus formation and systemic embolism. LAA function is determined by its flow velocities and fractional area change. This study was performed in order to determine the LAA functions with the anatomic M-mode echocardiography (AMME). Our study comprised 74 patients who had sinus rhythm and underwent transesophageal echocardiography (TEE) for various reasons. LAA fractional change (LAAFAC) was measured by manual planimetry in a transverse basal short-axis approach and LAA emptying and filling velocities also were measured. The AMME values were determined by an M-mode cross section from a cursor placed beneath the orifice of the LAA in transverse basal short-axis imaging. From these values LAA fractional shortening (LAAFS) and ejection fraction (LAAEF) were calculated. LAAEF was calculated by the Teicholz method. The comparisons were conducted, and no correlations between the LAA late filling and the anatomic M-mode values were found (for LAAFS r = 0.18; P > 0.05 and for LAAEF r = 0.19; P > 0.05). There were significant but poor correlations among the LAA late emptying with the anatomic M-mode measurements (for LAAFS r = 0.26; P < 0.05 and for LAAEF r = 0.30; P < 0.01), whereas, there were significant and good correlations between the LAAFAC and the anatomic M-mode values (for LAAFS r = 0.75; P < 0.01 and for LAAEF r = 0.78; P < 0.01). There were significant differences between the valvular heart disease group and the normal group, and between the valvular heart disease group and the ASD group (for LAAFAC P < 0.01, for LAAEF P < 0.01, for LAAFS P < 0.01). There was no difference between the normal group and the ASD group. Our study showed that the LAAEF and LAAFS in patients with sinus rhythm obtained via anatomical M-mode echocardiography is a new method, which can be used instead of left atrial appendage area change.  相似文献   
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Objective: Since asthma and atherosclerosis may share similar pathophysiological mechanism, this study is planned to investigate whether epicardial fat thickness (EFT), carotid and femoral intima media thicknesses, which are markers of subclinical atherosclerosis, are increased in patients with asthma. Methods: The study was designed as a cross-sectional study. A total of 154 participants (83 patients with asthma and 71 healthy volunteers) were enrolled into the study. Epicardial fat, carotid, and femoral intima media thicknesses were measured and recorded in both groups. The statistical difference between the two groups was examined. Results: Both carotid and femoral intima media thicknesses were significantly higher in patients with asthma compared to control group (5.52 ± 0.4 mm vs. 5.36 ± 0.4 mm; p = 0.038 and 5.64 ± 0.4 mm vs. 5.46 ± 0.5 mm; p = 0.036, respectively). However, there was not a significant difference in EFT between the groups [5.9 mm (5.3–6.6; IQR = 1.3) vs. 5.6 mm (4.7–6.5; IQR = 1.8); p = 0.1]. On comparison of control group and asthma subgroups (mild, moderate, and severe), there was a statistically significant difference among these four groups in terms of carotid and femoral intima media thicknesses (p = 0.002 and p < 0.001, respectively). Subgroup analyses showed that this difference was mainly due to patients with severe asthma. Conclusions: Carotid and femoral intima media thicknesses in asthmatic patients were found to be increased compared to the normal population. As a result, the risk of subclinical atherosclerosis in asthmatic patients may be high.  相似文献   
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Patients with mitral stenosis have usually blunted pulmonary venous (PV) flow, because of decreased mitral valve area and diastolic dysfunction. The authors compared changes in Doppler PV velocities by using transesophageal echocardiography (TEE) against hemodynamics parameters before and after mitral balloon valvotomy to observe relevance of PV velocities and endsystolic left atrial (LA) pressure-volume relationship. In 25 patients (aged 35 +/- 17 years) with mitral stenosis in sinus rhythm, changes in LA pressure and volumes were compared with PV velocities before and after valvotomy. Mitral valve area, mitral gradients, and deceleration time were obtained. Mitral valve area and mitral gradients changed from 1 +/- 0.2 cm2 and 14.6 +/- 5.4 mmHg to 1.9 +/- 0.3 cm2 and 6.3 +/- 1.7 mmHg, respectively (p<0.001). AR peak reverse flow velocity and AR duration decreased from 29 +/- 13 cm/s and 110 =/- 30 msec to 19 +/- 6 cm/s and 80 +/- 29 msec respectively (p<0.001). Transmitral Doppler E wave deceleration time decreased from 327 +/- 85 to 209 +/- 61 s and cardiac output increased from 4.2 +/- 1.0 to 5.2 +/- 1.1 L/minute (p<0.001). The changes in LA pressure were correlated with changes in S/D (r=0.57, p<0.05). The changes in endsystolic LA pressure-volume relationship were also correlated with changes in S/D (r=0.52, p<0.05). Endsystolic LA pressure-volume relationship decreased after mitral balloon valvotomy, as a result of a large decrease in pressure. PV systolic/diastolic (S/D) waves ratio reflects endsystolic LA pressure-volume relationship and may be used as another indicator of successful valvotomy.  相似文献   
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Introduction

Vertigo is classified as peripheral and central. Differentiation of stroke mimics is the most important diagnostic challenge. There is no clinical guidance for the indications of neuroimaging in isolated vertigo patients. The primary aim of this study is to test the diagnostic value of a DWI-MRI protocol to rule-out a central cause in patients with acute isolated vertigo in the ED.

Methods

We prospectively enrolled 144 patients who were presented with isolated vertigo to the ED. A detailed neurological examination and maneuvers were performed for differential diagnosis. All patients underwent CT and/or DW-MRI either during ED visit or at the follow-up, if necessary. Out-patient follow-up exams and evaluations were repeated until all patients had a definitive diagnosis.

Results

In the study, 137 of the 144 patients completed the follow-up period, and 34 of 137 patients were diagnosed with central vertigo. Six of 34 central vertigo patients had normal DW-MRI findings. One was diagnosed with migraine headache and five with vertebra-basilar insufficiency during the out-patient follow-up. One of the 28 patients with a pathological MRI was diagnosed with mass and the rest was stroke. The utility of DW-MRI in vertigo patients was moderately high (sensitivity: 82%, specificity: 100%). We found that age, history of HT, history of CAD and vertigo unresponsive to ED treatment were significantly associated with a central cause of vertigo.

Conclusion

We suggest that unresponsiveness to ED treatment, especially in patients with a history of HT and CAD, should alert physicians for central causes and warrant DW-MRI imaging.  相似文献   
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The value of echocardiography, especially tissue Doppler imaging (TDI), in the assessment of risk of postoperative atrial fibrillation (AF) after coronary artery bypass grafting (CABG) is not clear. One hundred two consecutive patients (80 men; mean age 61 +/- 10 years) who underwent elective isolated CABG were included in the study. All patients underwent conventional transthoracic echocardiography and TDI of the left and right heart before surgery. Also, 24-hour Holter recordings were obtained for all patients. The study end point was the development of postoperative AF. The surgical mortality rate was 2%. Postoperative AF occurred in 18 patients (18%). Patients with postoperative AF have been significantly older than patients without postoperative AF (73 +/- 7 vs 58 +/- 9 years, respectively; p <0.001). Compared with patients without postoperative AF, a significantly higher proportion of patients with postoperative AF experienced paroxysmal AF before surgery (6% vs 33%, respectively; p = 0.001). Patients with postoperative AF had a significantly larger mean left atrial diameter compared with patients without postoperative AF (37 +/- 3 vs 35 +/- 3 mm, respectively; p = 0.012). Multivariate logistic regression analysis identified age as the most significant predictor of postoperative AF (odds ratio 1.254, 95% confidence interval 1.127 to 1.396; p <0.001). Of the echocardiographic variables, only left atrial diameter was identified as a significant predictor of postoperative AF (odds ratio 1.250, 95% confidence interval 1.055 to 1.562; p = 0.047). In conclusion, in the prediction of postoperative AF after isolated CABG, preoperative transthoracic echocardiography, including both conventional echocardiography and TDI, is of little value.  相似文献   
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BACKGROUND: Sudden death is common in end-stage renal disease (ESRD). Cardiac arrhythmia is observed frequently in patients with ESRD and is thought to be responsible for this high rate of sudden death. This study investigated the prevalence and the predictors of arrhythmia in patients on maintenance dialysis. METHODS: Ninety-four patients on hemodialysis program were enrolled in the study. Routine laboratory results were noted. Arrhythmia, periods of silent ischemia, and heart-rate variability analyses were obtained from 24-hour Holter monitor recordings. Corrected QT (QTc) dispersion was calculated from 12-lead surface EKG. Echocardiographic and tissue Doppler examinations were performed on interdialytic days as well. Ventricular arrhythmia was classified according to Lown classification; classes 3 and above were accepted as complex ventricular arrhythmia (CVA). RESULTS: The mean age was 52.5+/-13.2 years; 44 (46.8%) were women. Ventricular premature contractions were detected in 80 (85.1%) patients, of whom 35 (37.2%) were classified as complex ventricular arrhythmia (CVA). Coronary artery disease, hypertension, and QTc dispersion appeared as independent factors predictive of CVA development. Atrial premature contractions (APC) were detected in 53 patients (56.4%) and supraventricular arrhythmia in 15 (16%) patients; all were identified as atrial fibrillation. Duration of dialysis therapy was found as an independent predictor of APC. CONCLUSION: Arrhythmia is frequently observed in ESRD patients receiving hemodialysis and may be responsible for the high rate of sudden mortality. Hypertension, CAD, and QTc dispersion are independent predictors of CVA, and duration of dialysis therapy is an independent factor affecting APC development in these patients.  相似文献   
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