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ABSTRACT

This study aimed to compare the physical and physiological responses of young football players of different categories during small-sided games (SSGs) played on different pitch sizes. Forty-eight (24 U-13 and 24 U-14) athletes played a 3 vs. 3 + 1 SSG in two experimental conditions: regular (36 × 27 m) and large pitch sizes (40 × 29 m). The total distance covered, the distances covered at different speed zones (0 to 6.9 km/h, 6.9 to 14.3, and 14.3 to 21.4), maximum heart rate, and mean heart rate were recorded. The results showed that older athletes covered larger distances during SSGs (p = 0.001; d = 0.937; large effect) and lower distances at the lowest (0–6.9 km/h) speed zone (p = 0.001; d = 0.657; moderate-to-large effect). Neither the physical nor physiological variables (except for distance covered between 14.3 and 21.4 km/h) differed between pitch sizes. This result indicates that pitch size may not impact the physical or physiological responses of U-13 and U-14 players during SSGs, but differences between categories were found. In conclusion, the development of tactical skills may be desirable to better explore the available space in the same age categories.  相似文献   
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The aetiology of vitiligo has not been fully elucidated, and several hypotheses have been investigated; among them, the most explored assumes an autoimmune basis for the disease. Supporting this hypothesis is the frequent co-occurrence of autoimmune diseases with vitiligo. In addition, various genetic loci associated with vitiligo harbour key immune response genes. Our general hypothesis is that autoimmunity-associated genes participate in the control of vitiligo susceptibility. To investigate this hypothesis, we tested for association between vitiligo and genes CYP27B1, REL, TNFAIP3 and IL2/IL21, all previously related to autoimmune diseases associated with vitiligo. The study was performed using two independent population samples: a family-based discovery set (211 trios) and a replication set (131 cases/119 controls). Statistically significant association with vitiligo was detected between markers of the REL and IL2 gene in the family-based sample. Both association signals were concentrated among patients displaying autoimmune comorbidity and non-segmental vitiligo. Evidence for validation was detected for IL2 marker. Our findings suggest REL and IL2 as new vitiligo susceptibility genes and reinforce the hypothesis of a shared genetic mechanism controlling vitiligo and other autoimmune diseases.  相似文献   
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We prospectively evaluated the effectiveness of contrast-enhanced ultrasonography (CEUS) for differentiation of benign versus malignant portal vein thrombosis (PVT). We studied a total of 43 patients with chronic liver disease, hepatocellular carcinoma-suggestive nodules and confirmed PVT, in whom the nature of the PVT was confirmed by follow-up imaging (US, computed tomography and/or magnetic resonance imaging) performed up to 6 mo after CEUS. PVT was assessed by US, Doppler US and CEUS with respect to vessel wall disruption and/or invasion, color Doppler vascularization, pulsed Doppler vascularization pattern and CEUS enhancement and vascularization pattern, and thrombi were classified as benign or malignant based on these findings. Follow-up studies revealed malignant PVT in 22 of the 43 patients (51%) and benign PVT in 21 patients (49%). CEUS findings were consistent with follow-up studies in 41 of the 43 patients (95%), with κ?=?0.903 (p < 0.0001), sensitivity?=?91% and specificity?=?100%, indicating that CEUS can be confidently used to differentiate benign from malignant portal vein thrombosis in the setting of chronic liver disease.  相似文献   
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Eosinophilic dermatosis of hematological malignancy is a paraneoplastic skin eruption associated with chronic lymphocytic leukemia and other B‐cell malignancies. It clinically resembles an insect bite reaction and it can precede the symptoms of the hematological malignancy or be related to a more aggressive course. Different treatments have been proposed, but partial response and recurrence are frequent. Herein, we describe a case of eosinophilic dermatosis associated with mantle cell lymphoma with remission after lenalidomide therapy.  相似文献   
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Objective: Analyze the hypothesis that swimming exercise, in rats suckled under distinct litter sizes, alters behavioral parameters suggestive of anxiety and recognition memory, and the electrocorticogram potentiation that occurs after the excitability-related phenomenon that is known as cortical spreading depression (CSD).

Methods: Male Wistar rats were suckled in litters with six or 12 pups (L6 and L12 groups). Animals swam at postnatal days (P) 8–23, or P60–P75 (early-exercised or late-exercised groups, respectively), or remained no-exercised. Behavioral tests (open field – OF and object recognition – OR) were conducted between P77 and P80. Between P90 and P120, ECoG was recorded for 2 hours. After this ‘baseline’ recording, CSD was elicited every 30 minutes over the course of 2 hours.

Results: Early swimming enhanced the number of entries and the percentage of time in the OF-center (P?<?0.05). In animals that swam later, this effect occurred in the L6 group only. Compared to the corresponding sedentary groups, OR-test showed a better memory in the L6 early exercised rats, and a worse memory in all other groups (P?<?0.05). In comparison to baseline values, ECoG amplitudes after CSD increased 14–43% for all groups (P?<?0.05). In the L6 condition, early swimming and late swimming, respectively, reduced and enhanced the magnitude of the post-CSD ECoG potentiation in comparison with the corresponding L6 no-exercised groups (P?<?0.05).

Discussion: Our data suggest a differential effect of early- and late-exercise on the behavioral and electrophysiological parameters, suggesting an interaction between the age of exercise and the nutritional status during lactation.  相似文献   

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