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Background The clinical characteristics of vitiligo in children and adolescents with an emphasis on thyroid dysfunction have only been reported in a few studies. Objective The purpose of this study was to examine the characteristics of children and adolescents with vitiligo and compare the incidence of thyroid dysfunction between them and controls without vitiligo at the same age. Methods A retrospective analysis of 324 Korean children and adolescents with vitiligo was performed. The results of thyroid function screening tests in them (n = 254) were compared with controls (n = 122). Results Of the total 324 children and adolescents with vitiligo, vitiligo vulgaris was the most common type (42.3%) and the most commonly involved site was the face (54.6%). A total of 15 of 254 (5.9%) patients screened for thyroid function were diagnosed with thyroid disease (four had Hashimoto’s thyroiditis; two, Graves’ disease; seven, subclinical hypothyroidism; and two, subclinical hyperthyroidism). None of the 50 patients with segmental vitiligo showed any thyroid dysfunction (P = 0.047). There was no significant difference in the incidence of thyroid disease between children and adolescents with vitiligo and the control group, in which seven of 122 (5.7%) showed thyroid dysfunction. Conclusion In this study, we demonstrated the characteristics of children and adolescents with vitiligo and also observed no significant difference in the incidence of thyroid disease between children and adolescents with vitiligo and the control group.  相似文献   
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Reproductive research in aging animals is often performed with very old rats manifesting spontaneous persistent estrus (SPE). However, Charles River (CD) Sprague Dawley rats present SPE as early as 6 months of age and thus are potentially very useful in such studies since the concomitant pathologies associated with old age can be avoided. Serum levels of LH, FSH, prolactin, estrogens, and progesterone were measured by RIA in 8 to 12 month SPE rats after rapid decapitation at 0300, 1000 or 1600 hr (8–11 rats/group). As reported by others in very old SPE rats, proiactin was high at 1600 hr (169±40 ng/ml) compared with levels at 0300 hr (43 ± 7 ng/ml) or 1000 hr (95 ± 25 ng/ml). LH and FSH values did not change with time of day, but those of FSH were consistently above baseline values of cyclic rats. Total estrogens were low (75 ± 9 pg/ml) at 1000 hr but significantly higher at both 0300 hr (127 ± 11.7 pg/ml) and 1600 hr (141 ± 23 pg/ml), resembling levels at about 1000 hr on proestrus in cyclic rats (125 ± 16 pg/ml). Average progesterone concentrations resembled baseline values of cyclic rats but varied widely (0.02 to 25 ng/ml). These findings suggest that the middle-aged SPE rat may be used in studies of the aging reproductive system, and that future studies with SPE rats should consider variations in prolactin, estrogen and progesterone with the time of day.  相似文献   
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