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Purpose: The purpose of this study was to test the hypothesis that with the range gate fixed, random adjustment of the pulse repetition frequency will offer a rapid and accurate way to avoid misinterpretation of range ambiguity. Background: Traditionally, to avoid the misdiagnosis of Doppler artifacts caused by range ambiguity, time must be spent on checking the flow patterns in the calculated phantom range gates. Methods: Twenty-four patients (mean age 64 ± 15 years, 15 men and nine women) with mitral regurgitation were included in the study. Pulsed Doppler evaluation was performed with sample volume initially at the shallow left ventricle and then, along the direction of ultrasonic beam, at the calculated range gate distal to the mitral valve to search for the high velocity Doppler signal. The highest velocity scale was initially selected. After detection of high velocity signal, the velocity scale was lowered to achieve the lower pulse repetition frequency. Results: For all patients, a high velocity regurgitant Doppler signal could be recorded both distal to the mitral valve and at the shallow left ventricle. Such signal persisted at the range gate distal to the mitral valve but disappeared at the range gate at the shallow left ventricle after manual adjustment of the velocity scale. The sensitivity, specificity, and accuracy of disappearance of the high velocity Doppler signal after adjustment of the pulse repetition frequency for confirmation of a phantom phenomenon are 100%, 100%, and 100%, respectively. Conclusions: Without the necessity of exact information about the pulse repetition frequency used, random adjustment of the pulse repetition frequency for the selected gate range is a rapid and exact method for initial differentiation of in situ from phantom signal in pulsed Doppler echocardiography.  相似文献   
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Background: Areca nut chewing is associated with the risk of obesity, metabolic syndrome, hypertension, and cardiovascular mortality. Although a few case reports or case series have suggested the link between areca nut chewing and cardiac arrhythmias, information about the relationship between areca nut chewing and atrial fibrillation (AF) is lacking. Thus, a nationwide ecological study was conducted to investigate this.Methods: Two national datasets, the nationwide population-based 2005 Taiwan National Health Insurance Research dataset (NHIRD) and the 2005 National Health Interview Survey (NHIS), were used for analyses. The clinical characteristics, inhabited area and medical histories for 375,360 eligible males were retrieved from the 2005 NHIRD. Health related behaviors including areca nut chewing, cigarette smoking, infrequent vegetable eating, and exercise habit were collected from the 2005 NHIS. The prevalence of AF and the areca nut chewing rate were evaluated by multivariate analysis.Results: Of the 375,360 males (mean age, 44 years old), 1,326 (0.35%) were diagnosed with AF. The higher areca nut chewing rate, the higher prevalence rate of AF in Taiwan (Spearman correlation coefficient r = 0.558, p = 0.007). After adjusting for other covariates, the current areca nut chewing rate was found to be independently associated with the prevalence of AF. The adjusted odd ratio for areca nut chewing was 1.02 (95% CI = 1.00-1.04) in risk of AF prevalence.Conclusions: Areca nut chewing is independently associated with the prevalence of AF in Taiwanese men. However, further exploration of the underlying mechanisms is necessary.  相似文献   
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Wegener’s granulomatosis (WG) is a systemic vasculitis characterised by the presence of necrotizing granulomas and classically manifests as a triad of upper and lower respiratory tract involvement along with glomerulonephritis. Other rather unusual presentations of WG include ocular, salivary gland, cutaneous, gastrointestinal and cardiac involvement. We report a case in a 51-year-old woman suffering from WG with positive antineutrophil cytoplasmic autoantibodies and antibodies directed against proteinase 3. Under maintenance therapy, the patient developed two thyroid nodules suspicious for malignancy which led to thyroidectomy. Postoperative histological examination revealed a tumour-forming WG mimicking a malignant thyroid tumour. We conclude that, although extremely rare, Wegener’s granulomatosis should be added to the list of differential diagnoses of tumours of the thyroid gland.  相似文献   
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BackgroundPulse wave velocity (PWV) is an excellent index of arterial stiffness and can be used to predict long-term cardiovascular (CV) outcome. In recent years, estimated PWV (ePWV), calculated by equations using age and mean blood pressure, was also reported to be a significant predictor of CV outcomes. However, there was no literature discussing about usefulness of ePWV in patients of acute myocardial infarction (AMI) for prediction of long-term CV and overall mortality. Therefore, we conducted this study for further evaluation.MethodsA total of 187 patients with AMI admitted to cardiac care unit were enrolled. ePWV were calculated by the equations for each patient.ResultsThe median follow-up to mortality was 73 months (25th–75th percentile: 8–174 months). There were 35 and 125 patients documented as CV and overall mortality, respectively. Under univariable analysis, ePWV could independently predict long-term CV and overall mortality. However, after multivariable analysis, ePWV could only predict long-term CV mortality in AMI patients.ConclusionsTo the best of our knowledge, our study was the first to evaluate the usefulness of ePWV in AMI patients for prediction of long-term CV and overall mortality. Our study showed ePWV was not only easy to calculate by formula, but also an independent predictor for long-term CV mortality in univariable and multivariable analyses. Therefore, ePWV was a simple and useful tool to measure arterial stiffness and to predict CV mortality outcome in AMI patients without the necessity for equipment to measure PWV.  相似文献   
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Acquired esotropia with high myopia may be associated with superotemporal eyeball prolapse from the muscle cone and the subsequent shift of extraocular muscles limits the success of the traditional recession–resection surgery. In this study, we report two patients diagnosed with myopic strabismus fixus with esodeviation >90 prism diopter. Marked axial elongation of globes was present in both the patients. They received medial rectus muscle recession and hemi-Jensen procedure in both eyes. Postoperatively, they showed significant improvement in abduction, elevation, and ocular alignment. We found that the combination of medial rectus muscle recession and hemi-Jensen procedure was effective in treating patients with acquired large esotropia with high myopia.  相似文献   
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