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This case report describes the use of two tissue expanders to correct a contour deformity of the neck, secondary to radical block dissection and radiotherapy for a recurrent parotid tumor. One flap was deepithelialized and then buried under the other to create the necessary bulk. This technique provided tissue similar in texture and color to the adjacent skin, and there is minimal donor site morbidity. It is, however, a staged procedure.  相似文献   
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Smith-Magenis syndrome is caused by a 17p11.2 deletion. It associates mental retardation, facial dysmorphism and brachydactyly; aberrant behavior and major sleep problems are present in 70% of the cases. It is probably under-diagnosed because the facial abnormalities are mild and the behavioral problems with hyperactivity and self-injuries are dominant, leading to the diagnosis of psychiatric pathology. However these behavioral problems are sufficiently characterized to allow the diagnosis of the syndrome and look for a 17p11.2 microdeletion. Otorhinolaryngologic, ophtalmologic, cardiac and renal abnormalities can be associated and their evaluation is necessary. Smith-Magenis syndrome is considered as a contiguous gene syndrome. Genes have been mapped and isolated to the critical region, but their participation in the pathogenesis of the syndrome remains unclear.  相似文献   
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Transient expression of axon collaterals plays an important role in enabling neurons to find appropriate targets during development. In the olfactory bulb, the numbers of both sensory neurons and their targets, the glomeruli, increase markedly during the postnatal period. In the present study, the morphology of developing olfactory axons in the olfactory bulb of 1-21-day-old rabbits was analyzed using stereological methods and the rapid Golgi technique. The findings demonstrated a change in axon morphology from the olfactory nerve layer to the glomeruli suggestive of a sequence in axon development. In the olfactory nerve layer, axons typically had knob-like growth cones and a few collateral branches. Close to glomeruli, axons increased in thickness, formed rather complex and irregular growth cones, and typically gave off many collaterals. Within glomeruli, the axons formed terminal branches and boutons. Extraglomerular branches were apparently removed once axons had entered a glomerulus, insofar as these branches often displayed morphological signs of degeneration. In contrast, collateral branches ending in the same glomerulus remained, indicating that formation of collaterals may assist olfactory axons in locating glomerular targets.  相似文献   
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A reduction of the growth hormone (GH) response to the alpha(2) adrenergic agonist clonidine is a neuroendocrine abnormality observed with reasonable consistency among human patients with mood and anxiety disorders. In previous primate studies, in comparison to predictably reared controls, monkeys exposed as infants to maternal variable foraging demand (VFD) rearing exhibited persistent elevations of cerebrospinal fluid (CSF) corticotropin-releasing factor (CRF), as well as other biological disturbances. As CRF has been demonstrated to inhibit GH release, the authors hypothesized that within VFD-reared subjects, animals with relatively high CRF concentrations would exhibit relatively diminished GH responses to clonidine. The current study examined the relationship between the GH response to clonidine in VFD-reared adult primates in relation to a range of both juvenile and follow-up CSF CRF concentrations. Nine bonnet macaques (Macaca radiata) were given ascending dosages of clonidine under ketamine anesthesia. Plasma samples for GH-like immunoreactivity were obtained throughout the session. A significant positive correlation was noted between juvenile CSF CRF concentrations and the levels of the neuropeptide observed in young adults. The mean of the serial CSF CRF concentrations exhibited a significant inverse relationship towards the GH response to clonidine in young adulthood, with relatively high CSF CRF associated with relatively attenuated GH responses to clonidine. These data raise the possibility that a reduced GH response to clonidine may inversely reflect trait-like increases of central nervous system (CNS) CRF activity.  相似文献   
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Context  Little is known about the incidence of secondary neoplasms after 15 to 20 years in children and adolescents who were treated for acute lymphoblastic leukemia. Objectives  To investigate the cumulative incidence of secondary neoplasms in pediatric patients treated for acute lymphoblastic leukemia over 30 years and to characterize late-occurring tumors. Design, Setting, and Patients  Retrospective study of 2169 patients with acute lymphoblastic leukemia treated between 1962 and 1998 at St Jude Children's Research Hospital, Memphis, Tenn, who achieved complete remission and had a median follow-up time of 18.7 years (range, 2.4-41.3 years). Main Outcome Measures  Cumulative incidences of secondary neoplasms in first remission and standard incidence ratios of observed rates compared with rates of cancer development in the general US population. Results  Secondary neoplasms developed as the first event in 123 patients and comprised 46 myeloid malignancies, 3 lymphomas, 14 basal cell carcinomas, 16 other carcinomas, 6 sarcomas, 16 meningiomas, and 22 other brain tumors. The cumulative incidence of secondary neoplasm was 4.17% (SE, 0.46%) at 15 years and increased substantially after 20 years, reaching 10.85% (SE, 1.27%) at 30 years. When meningiomas and basal cell carcinomas were excluded, the overall cumulative incidence was 3.99% (SE, 0.44%) at 15 years and 6.27% (SE, 0.83%) at 30 years, representing a 13.5-fold increase in overall risk compared with the general population. The cumulative incidence of each tumor type at 30 years was 2.19% (SE, 0.32%) for myeloid malignancy, 0.17% (SE, 0.10%) for lymphoma, 3.00% (SE, 0.59%) for brain tumor, 4.91% (SE, 1.04%) for carcinoma, and 0.57% (SE, 0.37%) for sarcoma. Conclusions  The cumulative incidence of secondary neoplasms increases steadily over 30 years after treatment of acute lymphoblastic leukemia. Although the majority of the late-occurring secondary neoplasms are low-grade tumors, the increase in incidence of more aggressive malignant neoplasms is significantly higher than expected in the general population. These results suggest that lifelong follow-up of acute lymphoblastic leukemia survivors is needed to ascertain the full impact of treatment and other leukemia-related factors on secondary neoplasm development.   相似文献   
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