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1.
Background. Extensive questioning of patients with a wide variety of skin disorders led to the impression that nocturnal overheating was probably an important factor in the initiation and the perpetuation of many skin disorders. Methods. In order to test the hypothesis, 12 “clean-skinned” subjects (6M/6F) aged 18 to 45 years were monitored electronically every 30 seconds during an 8 hour sleep period (2300 to 0700 hours), sleeping under a standard 10 tog duvet. Results. All the subjects were too hot by 3 to 4°C. All showed changes in their EEG patterns with reduced REM sleep, increased awakenings, and all showed changes in their sleep stage patterns. In addition, they all showed evidence of increased sweating in the “heat-sink” area. Conclusions. The mechanisms where by such changes could be implicated in the precipitation and perpetuation of skin disease are discussed. “Lifestyle” modification as a very effective, noninvasive, therapeutic regime is recommended. Further research along these lines would probably be very valuable and instructive.  相似文献   
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Galanin is a neuropeptide that regulates the secretion of several pituitary hormones, including prolactin (PRL) and growth hormone (GH). Galaninlike immunoreactivity (Gal-IR) and galanin mRNA in the rat anterior pituitary is cell lineage specific, with predominant expression in lactotrophs and somatotrophs. The authors examined the cellular distribution of human Gal-IR in seven normal postmortem pituitaries and 62 pituitary tumors by immunoperoxidase staining. In contrast to the rat, Gal-IR in human anterior pituitaries was present in corticotrophs scattered throughout the gland, but not in lactotrophs, somatotrophs, thyrotrophs, or gonadotrophs. Distinct Gal-IR also was present in hyperplastic and neoplastic corticotrophs in 19 of 22 patients with Cushing's disease. In noncorticotroph cell tumors, unequivocal Gal-IR was present in 5 of 11 GH-secreting tumors associated with clinical acromegaly, 9 of 18 nonfunctioning pituitary adenomas, and 2 of 14 prolactinomas. Of these galanin-positive tumors, four of the five GH-secreting adenomas, six of the nine nonfunctioning adenomas, and both of the prolactinomas also contained adrenocorticotropic hormone immunoreactivity (ACTH-IR). Immunostaining and in situ hybridization on adjacent sections using an 35S-labeled probe complementary to human galanin mRNA demonstrated predominant galanin expression in normal corticotrophs. Immunoelectron microscopy confirmed the presence of Gal-IR in pituitary cells characteristic of corticotrophs in both normal and neoplastic pituitaries. Thus, as in the rat, galanin gene expression in the human pituitary is cell-type specific. Unlike the rat, however, human galanin gene expression is restricted to the corticotroph lineage. Studies of tumors confirmed the observed coexpression of galanin and adrenocorticotropic hormone. The divergent cell type specificity of galanin production in human and rat pituitaries reflects different patterns of gene activation in these two species. In addition, these results suggest that galanin in the human pituitary may participate locally in the regulation of the hypothalamic-pituitary-adrenal axis.  相似文献   
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Background  

Inflammation and immune responses are considered to be very important in the pathogenesis of atherosclerosis. Lipid accumulation in macrophages of the arterial intima is a characteristic feature of atherosclerosis which can influence the inflammatory potential of macrophages. We studied the effects of lipid loading on the regulation of TNF expression in human monocyte-derived macrophages.  相似文献   
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An RNA-binding motif (RBM) gene family has been identified on the human Y chromosome that maps to the same deletion interval as the 'azoospermia factor' (AZF). We have identified the homologous gene family (Rbm) on the mouse Y with a view to investigating the proposal that this gene family plays a role in spermatogenesis. At least 25 and probably >50 copies of Rbm are present on the mouse Y chromosome short arm located between Sry and the centromere. As in the human, a role in spermatogenesis is indicated by a germ cell-specific pattern of expression in the testis, but there are distinct differences in the pattern of expression between the two species. Mice carrying the deletion Yd1, that maps to the proximal Y short arm, are female due to a position effect resulting in non-expression of Sry ; sex-reversing such mice with an Sry transgene produces males with a high incidence of abnormal sperm, making this the third deletion interval on the mouse Y that affects some aspect of spermatogenesis. Most of the copies of Rbm map to this deletion interval, and the Yd1males have markedly reduced Rbm expression, suggesting that RBM deficiency may be responsible for, or contribute to, the abnormal sperm development. In man, deletion of the functional copies of RBM is associated with meiotic arrest rather than sperm anomalies; however, the different effects of deletion are consistent with the differences in expression between the two species.   相似文献   
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Submaximal stimulation of mouse pancreatic acinar cells by acetylcholine (ACh) generates periodic Ca2+ responses sensitive to the membrane potential. Monitoring the muscarinic Ca2+ responses using patch-clamp whole-cell current recordings, we examined the mechanism of guanine nucleotide-binding protein (G protein)-receptor interaction in terms of the membrane potential. The lowest ACh concentration able to elicit consistent repetitive spikes was 50 nM, in the presence of which hyperpolarization increased and depolarization decreased the spike frequency. The saturating concentration was 10 microM, this induced a sustained response insensitive to voltage. Internal guanosine 5'-tri- and diphosphates (GTP, GDP) depressed and potentiated the voltage sensitivity, respectively, but not for the response to a saturating ACh concentration (10 microM). Internal guanosine 5'-O-(3-thiotriphosphate) (GTPgammaS) abolished the voltage sensitivity. The results indicate that the ACh-induced Ca2+ response is sensitive to the membrane potential and that a close linkage exists between voltage sensitivity and the G protein association/dissociation cycle in the muscarinic receptor.  相似文献   
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A retrospective review of rubella serological results carried out in the Virus Diagnostic Unit, University Hospital Kuala Lumpur (UHKL) from January 1993 to September 1999 showed the presence of rubella infection annually which appeared to increase periodically every two to three years. There was no statistical significant difference in the rubella positive rate between male and female population aged 14 to 48 years. Congenital rubella infections (CRI) occurred in babies delivered in UHKL yearly from 1993 to 1998 with an average incidence rate of 48 per 100,000 deliveries. Peaks of rubella cases appeared to be followed by an increase in incidence of CRI cases 6 to 9 months later. The study showed that only 50.8% clinically diagnosed rubella was confirmed by laboratory finding. This study also showed an increase of rubella activity for the months of July, August and September 1999 and this may herald an increase of CRI cases in the coming millennium.  相似文献   
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