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We present a case of a 79-year-old African-American woman with scimitar syndrome and associated dextrocardia. This case represents, to our knowledge, the oldest living patient described in the literature with scimitar syndrome.  相似文献   
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We conducted a population-based study to examine the association between clinical and Doppler echocardiographic characteristics and physicians' recommendation for endocarditis prophylaxis. Of 127 consecutive Olmsted County, Minnesota, residents with newly documented isolated mitral valve prolapse, endocarditis prophylaxis was recommended three to four times more often in patients under 40 years compared with those more than 60 years of age. Using multiple logistic regression, for every 10-year increment in age, there was a 30% independent reduction in recommendations for endocarditis prophylaxis. Doppler evidence of mitral regurgitation was also independently associated with recommendations for endocarditis prophylaxis. Observations from physical examination, including systolic murmur and systolic click, were weakly associated with endocarditis prophylaxis recommendations. Mitral valve appearance (thickened vs not) was not associated with endocarditis prophylaxis. Although current recommendations for endocarditis prophylaxis and mitral valve prolapse do not address age and Doppler-detected mitral regurgitation, these variables are strongly associated with clinical decisions. Prospective, longitudinal, population-based studies are needed to define endocarditis risk further in subgroups with mitral valve prolapse to provide a more scientific basis for clinical decision making.  相似文献   
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There are many concerns about safety of food contaminated with antibacterial residues. This study was designed to investigate the occurrence of chloramphenicol (CAP) residue in broiler chickens tissues, namely liver, kidney and muscle. One hundred and sixty broiler chickens carcasses were collected from three provinces of Iran. Four Plate Test (FTP), ELISA and HPLC were used to qualify and quantify the contamination of the samples with CAP. The results of FPT revealed that up to 17.5% of the samples were contaminated with the antibiotic. The ELISA assay showed that out of 28 positive samples in FPT, 22 liver, 21 kidney and 14 muscle samples were positive for CAP. ELISA analyses demonstrated that the minimum and maximum levels of 0.54 and 155.2 ng/g were detected in the kidney and liver, respectively. HPLC analyses confirmed the ELISA findings although the level of contamination was lower than that of ELISA. These data showed that despite the prohibition of CAP application in food animals including poultry, the CAP residue was detectable indicating an illegal use of this antibiotic. Our findings also demonstrated the application of sensitive and more specific analytical assays in screening and quantitation of CAP residues in food products.  相似文献   
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The utility of transthoracic two-dimensional echocardiography in patients with aortic dissection was assessed by retrospective analysis in 67 patients: 31 patients with DeBakey type I, 21 patients with type II, 10 patients with type III, and five patients with false-positive diagnoses. Aortic dissection was correctly identified by two-dimensional echocardiography in 49 patients; 13 had false-negative diagnoses. Therefore the sensitivity was 79%, and the positive predictive accuracy was 91%. Transthoracic two-dimensional echocardiography is a reasonable screening technique for diagnosis of aortic dissection.  相似文献   
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Transesophageal two-dimensional echocardiography (TEE) was evaluated in 11 patients who underwent myocardial revascularization. The TEE transducer was positioned to view the left ventricular (LV) short-axis at the level of the papillary muscles (midcavity). Good quality echocardiographic images were obtainable in ten of 11 patients. Global LV function was assessed by measuring LV end-diastolic and end-systolic area and computing the fractional area change (FAC). Measurements of LV areas and FAC had excellent intraobserver reproducibility. Regional LV function was analyzed in two ways after dividing the short-axis view of the LV into four or five anatomic segments. Systolic wall thickening (SWT) of the myocardium was measured in each of four segments by digitization of the endocardial and epicardial borders of the LV and determining the fractional wall thickening. Measurements of SWT were not reproducible, primarily because of a difficulty in delineating the epicardial border of the LV accurately. In the second method, regional wall motion (RWM) in each of five segments was graded according to a previously developed scoring system. RWM analysis proved to be a measurement with excellent interobserver and intraobserver reproducibility. TEE was performed without complication and found to be a reproducible method for assessing global and regional LV function. Quantitative analysis is tedious and, therefore, currently not available on-line in the operating room.  相似文献   
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