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The occurrence of atrial fibrillation (AF), especially in patients with mitral regurgitation (MR), is related to the degree of left atrial (LA) myopathy, remodeling and fibrosis, that are responsible of LA electrical inhomogeneity and abnormal conduction velocities. Speckle tracking echocardiography (STE) has recently enabled the quantification of longitudinal myocardial LA deformation dynamics. Our aim was to investigate by STE the effects of the occurrence of paroxysmal AF on LA myocardial deformation, in a population of patients with asymptomatic chronic MR. We compared two groups of a total of 197 patients with MR: 54 with history of paroxysmal AF and 143 with MR alone. Subgroups were created according to MR degree. Peak atrial longitudinal strain (PALS) was measured in all subjects. Values were obtained by averaging all segments (global PALS), measured in the 4-chamber and 2-chamber views. Compared to the mild MR group (46.1?±?4.9%), global PALS was lower in moderate MR group (22.1?±?5.8%) and further reduced in the severe MR group (13.9?±?4.2%; overall P?相似文献   
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BACKGROUND: The study aim was to investigate possible changes in serum anti-Müllerian hormone (AMH) levels during controlled ovarian hyperstimulation (COH), and their possible relationship with follicular development and other ovarian hormones. METHODS: A total of 93 women undergoing COH with GnRH agonist and FSH was studied prospectively. Serum levels of AMH, inhibin B, estradiol (E(2)), progesterone, testosterone and Delta(4)-androstenedione were measured when pituitary suppression was achieved (baseline), on days 6 and 8 of FSH treatment, and on the day of hCG. The number of small (<12 mm) and large (>/=12 mm) antral follicles were estimated using ultrasound. RESULTS: Serum AMH levels declined progressively (baseline, 1.21 +/- 0.11 ng/ml; day 6, 0.91 +/- 0.09 ng/ml; day 8, 0.77 +/- 0.08 ng/ml; and day of hCG, 0.53 +/- 0.06 ng/ml), whereas-as expected-the other hormone levels increased during FSH treatment. Throughout COH, serum AMH levels correlated positively with the number of small but not large antral follicles, and with inhibin B serum levels. No correlation between AMH and the other hormones was observed. CONCLUSIONS: Serum AMH levels decline gradually during multiple follicular maturation, probably reflecting the dramatic reduction in the number of small antral follicles due to COH, and confirming the scarce AMH expression by larger follicles.  相似文献   
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The presence and likelihood of an alternative diagnosis to pulmonary embolism is an important variable of the Wells' prediction rule for establishing clinical probability. We assessed whether evoking specific alternative diagnoses would reduce the probability of pulmonary embolism enough to forego further testing. We retrospectively studied a cohort of 965 consecutive patients admitted for suspicion of pulmonary embolism at three medical centers in Europe in whom the presence of an alternative diagnosis at least as likely as pulmonary embolism was recorded before diagnostic testing. We divided the patients into 15 categories of alternative diagnoses evoked. We then assessed the prevalence of pulmonary embolism in each diagnostic category and compared it to the prevalence of pulmonary embolism in a reference group (patients with no alternative diagnosis or a diagnosis less likely than pulmonary embolism). The prevalence of pulmonary embolism in the reference group was 48%. The presence of an alternative diagnosis as or more likely strongly reduced the probability of pulmonary embolism (OR 0.15, 95% CI: 0.1-0.2, p < 0.01). In almost every diagnostic category, the prevalence of pulmonary embolism was much lower than in the reference group with an odds ratio below or near 0.2. Bronchopneumonia (OR 0.4, 95% CI 0.2 to 0.7) and cancer (OR 0.6, 95% CI 0.3 to 1.5) reduced the likelihood of pulmonary embolism to a lower extent. Evoking an alternative diagnosis at least as likely as pulmonary embolism reduces the probability of the disease, but this effect is never large enough to allow ruling it out without further testing, especially when bronchopneumonia or cancer are the alternative diagnoses considered.  相似文献   
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