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Neuronal perikarya isolated from developing rat brain cortex were employed for studying the effect of hypothyroidism on RNA and protein synthesis in vitro. Neuronal protein synthesis was inhibited by hypothyroidism during the second week of brain development. Thyroxine treatment in vivo stimulated neuronal protein synthesis in hypothyroid rats. The synthesis of neuronal RNA was depressed by hypothyroidism in 7-day old rats. The inhibition of neuronal protein synthesis due to the lack of thyroid hormaones was restricted to membrane-bound ribosomes. The results suggest that the maturation of the neurone is very sensitive to hormonal imbalance during the critical period of brain development.  相似文献   
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Arthur Vineberg     
Brian Bérubé 《CMAJ》1981,125(10):1176
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Miniature swine MHC antigens from three inbred herds were examined by two-dimensional gel electrophoresis. These antigens were found to constitute a series of complex glycoproteins displaying haplotype-specific patterns that allowed the distinction of both class I and class II molecules among the three haplotypes. Selected outbred pig antisera reacted with a subset of class I antigens, suggesting the presence of at least two distinct molecular species among these antigens. Similarly, alloantisera reacting with mouse Ia antigens and a monoclonal anti-human DR were shown to immunoprecipitate a subset of class II molecules. Examination of the cells from two recombinant haplotypes demonstrated that both independent recombinational events took place between the class I and class II genes.  相似文献   
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Inflammatory reaction to ocular trauma is known to be related to prostaglandins. To further evaluate this phenomenon in human, PGE1 and E2 were measured by R.I.A. after silicic acid chromatography in aqueous humour of 26 patients before and 3 days after surgery for unilateral senile cataract (posterior chamber implant after extracapsular surgery). 13 out of these patients were treated with indomethacin by enteral route and 13 were not treated.PGE2 levels increased in all non-treated patients from : m < 214 pg/ml before surgery, to 2666 ± 869 pg/ml (range : 257 - 8728) p < 0.001 after surgery. PGE2 levels did not increase in indomethacin-treated patients. PGE1 levels did not increase significantly in non-treated as in treated patients.1) Intra-ocular surgery is followed in human by a constant increase of the only PGE2 in the aqueous humour. 2) Indomethacin inhibits this increase. 3) The post-surgical increase in the permeability of blood-aqueous barrier appears to be related to a release of PGE2.  相似文献   
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