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Melatonin, the main hormone produced by the pineal gland, is secreted in a circadian manner (24‐hr period), and its oscillation influences several circadian biological rhythms, such as the regulation of clock genes expression (chronobiotic effect) and the modulation of several endocrine functions in peripheral tissues. Assuming that the circadian synchronization of clock genes can play a role in the regulation of energy metabolism and it is influenced by melatonin, our study was designed to assess possible alterations as a consequence of melatonin absence on the circadian expression of clock genes in the epididymal adipose tissue of male Wistar rats and the possible metabolic repercussions to this tissue. Our data show that pinealectomy indeed has impacts on molecular events: it abolishes the daily pattern of the expression of Clock, Per2, and Cry1 clock genes and Pparγ expression, significantly increases the amplitude of daily expression of Rev‐erbα, and affects the pattern of and impairs adipokine production, leading to a decrease in leptin levels. However, regarding some metabolic aspects of adipocyte functions, such as its ability to synthesize triacylglycerols from glucose along 24 hr, was not compromised by pinealectomy, although the daily profile of the lipogenic enzymes expression (ATP‐citrate lyase, malic enzyme, fatty acid synthase, and glucose‐6‐phosphate dehydrogenase) was abolished in pinealectomized animals.  相似文献   
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Motor evoked potentials (MEPs) from the arms and legs to transcranial stimulation of the motor cortex and somatosensory evoked potentials (SSEPs) from stimulation of the nerves of the arms and legs, were recorded in 11 patients with hereditary spastic paraplegia. Electrophysiological abnormalities were found to be distributed differently among the systems examined; the longer the pathway, the higher the incidence and severity of impairment. MEPs from the leg were either absent or clearly reduced or prolonged in all patients. Eight patients showed abnormal cortical SSEPs on stimulation of the leg (absent or reduced responses in four, slowed central conduction velocity in seven), but only two of these patients had abnormal MEPs from the arm (absent responses). Cortical SSEPs on stimulation of the median nerve were reduced in two patients. Mean values of amplitude and central conduction velocity for MEPs and SSEPs from the leg were significantly different between patients and controls. Such differences were not found for either MEPs or SSEPs from the arm. This distribution of abnormalities, which suggests a differential involvement of the spinal pathways, parallels the reported pathological pattern in which degeneration of axons is more common and severe in the motor and sensory fibres supplying the leg.  相似文献   
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We describe a case of Munchausen's syndrome by proxy in a 12 years old child. The administration of glibenclamide by the mother led to severe hypoglycemias in the child, who underwent various instrumental researches and a subtotal pancreatectomy before the final diagnosis could be reached. The diagnosis also was possible with the substantial help of an accurate psychological survey. The case solution, with disappearance of hypoglycemias, was made possible by the removal of the maternal presence settled by the juvenile court.  相似文献   
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The authors conducted a clinical and radiographic study on a group of 43 patients with hip arthroprostheses selected from the three-year period from 1984 to 1987, characterized by no immediate postoperative complications, no positional defects on X-ray examination, and with a Renther test greater than 1. Prostheses were cemented, cementless and combined. Scintigraphy was evaluated for areas of subdivision in the proximal end of the femur and acetabulum, making a semi-quantitative comparison of the intensity of captation of each area with that of the skull and sacroiliac synchondrosis. The authors emphasize that this procedure is both reliable and easy for the early determination (pre-clinical and pre-radiographic) of any complications. A scintigraphic examination of the single areas was also capable of revealing the site and entity of prosthetic bone-to-implant interactions. According to the results reported, PCA prostheses seem to be characterized by better biocompatibility.  相似文献   
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