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《Science & Sports》2006,21(2):93-95
IntroductionThe purpose of this study was to evaluate the effect of sprint training on plasma catecholamine concentrations in response to a-6 second-sprint exercise in adolescent boys (GE). Moreover, to judge of the respective effects of training and pubertal maturation, we proposed the same protocol to a control group of adolescents (GT).ResultsHigher performances (Pmax) were reported in GE after 6 months but did not change in CG. In response to sprint exercise, no change was found in maximal lactate concentrations (Lamax) or in plasma noradrenaline concentrations (NA) in GE and GT. However, higher (A) responses were reported in GE and CG after the 6 seconds-sprint test and no difference was observed in this increase between the groups.ConclusionThese results suggest that in adolescent boys, sprint training may enhance performances but not catecholaminergic responses to short cycle ergometer sprinting.  相似文献   
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We have presented a rare case of primary involvement of the anterior mediastinum by osteogenic sarcoma in which CT was useful in demonstrating calcium within the mass, and in distinguishing the mass from surrounding bony structures. Although rare, extraosseous osteogenic sarcoma should be included in the differential diagnosis of a calcified anterior mediastinal mass.  相似文献   
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Fifty-five children (34 boys, 21 girls; age range, 1 day to 18 years) with increased echogenicity of the renal medullary pyramids at ultrasound evaluation were identified. The clinical diagnoses associated with hyperechoic medullary pyramids could be separated based on the presence or absence of hypercalciuria. Patients with drug-induced hypercalciuria included 10 infants treated with furosemide, two treated with long-term steroid therapy, and one treated with excessive amounts of vitamin D. Other clinical conditions associated with hypercalciuria included renal tubular acidosis (n = 10), Bartter syndrome (n = 5), hyperparathyroidism (n = 3), Williams syndrome (n = 2) and medullary sponge kidney (n = 2). Ten children with transient renal insufficiency and three with sickle cell disease had normal urine calcium concentration. Isolated disease entities accounted for the remainder of cases. A specific diagnosis can usually be made in a patient with hyperechoic renal medullary pyramids by using a systematic clinical approach that includes evaluation of patient age, serum and urine calcium concentration, and renal function.  相似文献   
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ObjectiveWe examine remission rate probabilities, recovery rates, and residual symptoms across 36 weeks in the Treatment for Adolescents with Depression Study (TADS).MethodThe TADS, a multisite clinical trial, randomized 439 adolescents with major depressive disorder to 12 weeks of treatment with fluoxetine, cognitive–behavioral therapy, their combination, or pill placebo. The pill placebo group, treated openly after week 12, was not included in the subsequent analyses. Treatment differences in remission rates and probabilities of remission over time are compared. Recovery rates in remitters at weeks 12 (acute phase remitters) and 18 (continuation phase remitters) are summarized. We also examined whether residual symptoms at the end of 12 weeks of acute treatment predicted later remission.ResultsAt week 36, the estimated remission rates for intention-to-treat cases were as follows: combination, 60%; fluoxetine, 55%; cognitive–behavioral therapy, 64%; and overall, 60%. Paired comparisons reveal that, at week 24, all active treatments converge on remission outcomes. The recovery rate at week 36 was 65% for acute phase remitters and 71% for continuation phase remitters, with no significant between-treatment differences in recovery rates. Residual symptoms at the end of acute treatment predicted failure to achieve remission at weeks 18 and 36.ConclusionsMost depressed adolescents in all three treatment modalities achieved remission at the end of 9 months of treatment.  相似文献   
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