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The International Journal of Cardiovascular Imaging - Although bicuspid aortic valve (BAV) is one of the most common congenital heart diseases, clinical data associated with valve dysfunction are...  相似文献   
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Modified vaccinia virus Ankara vaccine (MVA-BN; Bavarian Nordic) is recommended to contacts of mpox cases up to 14 days post-exposure but the effectiveness of this strategy is unknown. Among 108 adults (≥ 18 years old) who received one dose of MVA-BN after exposure to mpox, 11 (10%) cases of breakthrough mpox were observed. Sexual exposure was associated with the risk of breakthrough mpox (p = 0.0179). Samples taken from vaccinated breakthrough mpox cases had similar rates of infectious virus isolation than unvaccinated mpox cases.  相似文献   
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BACKGROUND: While normal at rest, left ventricular (LV) systolic function may become abnormal during exercise in patients with aortic stenosis. Once contraindicated in patients with aortic stenosis, exercise testing is now recommended in asymptomatic patients with aortic stenosis to elicit symptoms and thereby ascertain the need for aortic valve replacement. However, the clinical significance of an abnormal LV response to exercise in asymptomatic patients with aortic stenosis remains unknown. OBJECTIVE: The aim of this study was to evaluate the clinical implications of an abnormal LV response during exercise in the setting of aortic stenosis. METHODS: We monitored the LV response to exercise by 2D-Doppler echocardiography during a symptom limited semirecumbent bicycle exercise in 50 patients with tight aortic stenosis (aortic valve area < or = 1.0 cm(2)) and a normal LV systolic function (LV ejection fraction, EF > or = 50%) and followed them for an average of 11 months. RESULTS: Twenty patients had an abnormal LV response to exercise with a mean decrease in LV EF from 64 +/- 10 to 53 +/- 12% while 30 patients had a normal LV response to exercise with a mean increase in LV EF from 62 +/- 7 to 70 +/- 8%. Patients with an abnormal LV response during exercise were more likely to develop symptoms during exercise than patients with a normal LV response: 80% versus 27% (P< 0.0001). The survival free of cardiac events was significantly lower in patients with abnormal LV response to exercise than in patients with a normal response (P = 0.03). CONCLUSION: Exercise echocardiography provides objective data that facilitate interpretation of exercise elicited symptoms in asymptomatic patients with severe aortic stenosis. In addition, an abnormal LV response to exercise may predict a poor outcome.  相似文献   
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A novel method based upon liquid chromatography coupled to ion trap mass spectrometry (MS) detection with electrospray ionization interface has been developed for the identification and quantification of colchicine in plasma or whole blood. Colchicine was isolated from plasma using a liquid-liquid extraction with dichloromethane at pH 8.0 and embutramide as an internal standard, with satisfactory extraction recoveries. Solutes were separated on a 3-microm C18 Uptisphere (Interchim) column (150 x 2.0-mm i.d.) using acetonitrile/2 mM NH4COOH pH 3.8 buffer (50:50, v/v) as the mobile phase with a flow-rate of 200 microL/min. Data were collected either in full-scan MS mode at m/z 100-450 or in full-scan MS-MS mode, selecting the ion m/z 400.1 for colchicine and m/z 294.1 for embutramide. The most intense daughter ion of colchicine (m/z 358.1) and embutramide (m/z 207.9) were used for quantification. Retention times were 2.40 and 4.25 min for colchicine and embutramide, respectively. Calibration curves were linear in the 0.50-50 ng/mL range. The limits of detection and quantification were 0.05 ng/mL and 0.50 ng/mL, respectively. The intra- and interassay precisions were < 14%, and the intra- and interassay accuracies were in the 97-105.8% range at either 2 or 20 ng/mL. A fatal case of colchicine self-poisoning with a lethal blood concentration of 60 ng/mL and nonfatal case with a plasma sample collected very late (at least 36 h after the ingestion) are presented. The described method enables the unambiguous identification and quantification of colchicine with a very good sensitivity, using only 1 mL of sample.  相似文献   
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