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1.
We describe the isolation of Trichophyton mentagrophytes in two family-operated farms where the animals were suffering skin ailments characterized by a swelling and a reddening of the back and flanks.This condition affected 2 and 5% respectively of the animals on the farms, the younger ones being more frequently affected.  相似文献   
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Significant differences in gross wall chemical composition were detected in four commercial Agaricus bisporus strains. All were grown under the same conditions and their walls prepared by a mild method of breakage. A more detailed analysis of the wall fractions, isolated by means of their distinct solubilities, also showed striking structural differences among the four strains studied. The detected differences, not only in the overall composition of the wall but also in the polysaccharide structure, could assist in the characterization of strains and/or varieties of the commercial basidiomycete A. bisporus.  相似文献   
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  总被引:8,自引:0,他引:8  
Abundant representation of sharks in the fossil record makes this group asuperb system in which to investigate rates and patterns of molecularevolution and to explore the strengths and weaknesses of phylogeneticinferences from molecular data. In this report, the molecular evolution ofthe cytochrome b gene in sharks is described and the information related toresults from phylogenetic analysis of the data evaluated in the light of aphylogeny derived independently of the molecular data. Across divergentlineages of sharks there is evidence for significant substitution ratevariation, departure from compositional equilibrium, and substantialhomoplasy; nevertheless, the signal of evolutionary history is evident inpatterns of shared transversions and amino acid replacements.  相似文献   
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Reduced expression of the Indy (I'm Not Dead, Yet) gene in D.?melanogaster and its homolog in C.?elegans prolongs life span and in D.?melanogaster augments mitochondrial biogenesis in a manner akin to caloric restriction. However, the cellular mechanism by which Indy does this is unknown. Here, we report on the knockout mouse model of the mammalian Indy (mIndy) homolog, SLC13A5. Deletion of mIndy in mice (mINDY(-/-) mice) reduces hepatocellular ATP/ADP ratio, activates hepatic AMPK, induces PGC-1α, inhibits ACC-2, and reduces SREBP-1c levels. This signaling network promotes hepatic mitochondrial biogenesis, lipid oxidation, and energy expenditure and attenuates hepatic de novo lipogenesis. Together, these traits protect mINDY(-/-) mice from the adiposity and insulin resistance that evolve with high-fat feeding and aging. Our studies demonstrate a profound effect of mIndy on mammalian energy metabolism and suggest that mINDY might be a therapeutic target for the treatment of obesity and type 2 diabetes.  相似文献   
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Fungicides to control mycopathogens of commercial Agaricus bisporus, a mushroom cultivated for human consumption, are a major field of study, since these chemicals are toxic to both the host and its fungal parasites. The fungicide Prochloraz-Mn, used at its LD50 for A. bisporus, partially inhibited protein biosynthesis in the vegetative mycelial cell walls of this mushroom and caused significant changes in cell-wall polysaccharide structure, as deduced by methylation analysis and gas liquid chromatography-mass spectrometry (GLC-MS). Furthermore, the aggregated mycelial walls showed distinct alterations in their overall chemical composition following the administration of Prochloraz-Mn at the LD50 and the LD50 x1000. As expected, GLC-MS studies indicated that the latter dose caused more appreciable differences in polysaccharide structure. The decrease in mushroom crop yields obtained from industrial cultures treated with Prochloraz-Mn to control V. fungicola infection depended on the dose of the fungicide employed, whereas fruit-body morphology was only slightly affected at the highest Prochloraz-Mn concentration used.  相似文献   
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We have studied the effects of dietary depletion of vitamin E and selenium on endogenous ubiquinone-dependent antioxidant system. Deficiency induced an increase in both coenzyme Q9 and Q10 in liver tissue, reaching a maximum between 4 and 7 weeks of deficient diet consumption. Cytochrome b5 reductase polypeptide was also enriched in membranes after 5 weeks of deficient diet consumption. Substantial DT-diaphorase activity was found in deficient, but not in control plasma membranes. Deficient membranes were very sensitive to lipid peroxidation, although a great protection was observed after incubation with NAD(P)H. Our results show that liver cells can boost endogenous ubiquinone-dependent protective mechanisms in response to deficiency in vitamin E and selenium.  相似文献   
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  总被引:5,自引:2,他引:5  
There is marked heterogeneity of nucleotide composition in mitochondrialDNA across divergent animals. Differences in nucleotide compositionpresumably reflect differences in directional nucleotide substitution forA+T or G+C nucleotides. In mitochondrial DNA, there is A+T directionalnucleotide substitution in most (if not all) animals surveyed, and themagnitude of directional A+T nucleotide substitution differs greatly withinand among groups. Differences in directional nucleotide substitution amonglineages of mammals can be explained by changes in metabolic physiology.This relationship is thought to be mediated by the effect of oxygenradicals because these toxic compounds are by-products of aerobicmetabolism and are known mutagens. Association between metabolism andnucleotide composition provides additional evidence in favor of thehypothesis that rates and patterns of nucleotide substitution inmitochondrial DNA can be influenced by factors that impinge on rates ofendogenous DNA damage.  相似文献   
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