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561.
Mice infected with the Venezuelan equine encephalomyelitis virus showed a significant decrease in the GABA content of cerebral hemispheres. Activity of the enzyme which synthetizes GABA, glutamate decarboxylase, is also reduced in whole cerebral hemispheres, neostriatum, and frontal cortex of infected animals, as compared to values obtained from the same regions of control mice. No significant difference was demonstrated in the activities of GABA transaminase, glutamate dehydrogenase, lactate dehydrogenase, succinate dehydrogenase and NAD-malate dehydrogenase in any of the regions studied. The results suggest that the viral infection produced an alteration in the mechanism of GABA synthesis. 相似文献
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T. A. Ryder M. Lynn MacKenzie Rachel Lewinsohn J. Pryse-Davies M. Sandler 《Histochemistry and cell biology》1980,67(2):199-204
Summary The enzymes monoamine oxidase A (MAO A), monoamine oxidase B (MAO B) and benzylamine oxidase (BzAO) have been localized histochemically in the human uterus during various phases of the menstrual cycle. The results show a large increase in MAO A activity in the endometrial gland cells in the secretory phase of the cycle. MAO B activity was found in both endometrium and myometrium but did not show a cyclical variation in activity. BzAO was localized primarily in the tunica media of the myometrial blood vessels. These observations have been supported by parallel biochemical assays.This research was supported by the Conselho Nacional de Desenvolvimento Cientifico e Tecnologico (CN Pq), Brazil and The Wellcome Trust, U.K., who defrayed the salary of Rachel Lewinsohn 相似文献
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The two subspecies of ruffed lemurs (Vareica variegata variegata andVarecia variegata rubra) have been maintained in captivity since 1959 and all institutions which hold ruffed lemurs have contributed data to theVarecia International Studbook. Studbook data were used to analyze inbreeding effects on survival in both subspecies ofVarecia. Several variables, including offspring's inbreeding coefficient, litter size, mother's inbreeding coefficient, and mother's
age, were examined for significant associations with percent survivorship per litter. Percent survivorship per litter was
negatively correlated to the offspring inbreeding coefficient in the black and white ruffed lemurs (p<0.001) but no significant
association was found for red ruffed lemurs. Although emphasis has been put towards the status of the red ruffed lemurs due
to the small founder size, the black and white ruffed lemurs should also be managed with care due to the lower tolerance to
inbreeding in captivity. 相似文献