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Fourteen fresh run salmon Satmo salar L. with early extant lesions of ulcerative dermal necrosis (UDN) were kept in separate tanks and treated with zinc free malachite green. Ten of the fish were held at 10° C and 4 at 2° C. The treatment precluded infection with Saprolegnia fungus and allowed natural resolution of the lesions. There was a marked difference in rate of healing between warm and cold water conditions.
Histological examination of healing lesions at different stages showed that there was a primary invasion of cuboidal epithelium over the collagen scar followed by a phase of disorganized proliferation which eventually organized itself into normal epithelium. Melanocytes were very obvious in the dermis of healing lesions.  相似文献   
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Synthesis and NMR spectra of 13C-labeled coenzyme A esters   总被引:1,自引:0,他引:1  
The synthesis of coenzyme A thioesters of 13C-labeled acetate, propionate, succinate, and methyl malonate is described. The average yields were 94%. The 13C-NMR spectra were determined to provide a reference for the resonance positions of these metabolites. The synthesis of coenzyme thioesters of small-molecular-weight acids labeled with 13C has not been described previously, nor have the resonance positions been previously reported.  相似文献   
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We have used DFT methods to determine the structures and thermochemistry of several nitro-substituted diborane molecules in an attempt to rate their potential as high energy materials. The properties of nitrodiborane, three isomers of dinitrodiborane, trinitrodiborane, and tetranitrodiborane were calculated using the B3LYP density functional method. Our results indicate that the absolute enthalpy of combustion decreases with increasing nitro content, in contrast with other nitro-substituted systems that have been studied previously.  相似文献   
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To evaluate the ontogeny of the brain neurotransmitters norepinephrine, dopamine, serotonin and the metabolites hydroxyindoleacetic acid and homovanillic acid, we measured these neurotransmitters in 10 brain areas at three ages in fetal sheep and two ages in newborn lambs. Norepinephrine exhibited an increase only at 25-30 days after birth in the midbrain, lateral hypothalamus, dorsal medial hypothalamus and ventral medial hypothalamus. Dopamine concentration was very low and did not change over the ages examined. Homovanillic acid decreased after 125 days in the cerebellum, but this change is probably not biologically meaningful, since there were no statistically significant changes in homovanillic acid in other brain areas. Serotonin increased at 25-30 days after birth in the ventral medial hypothalamus, but changes in other brain areas were not significant. Hydroxyindoleacetic acid reached its greatest concentration at 1-5 days after birth in nine of the ten brain areas examined. Thus we conclude that the serotonin system is undergoing more change in the last third of gestation and first month of extrauterine life than the norepinephrine or dopamine systems.  相似文献   
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