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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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A case of chromomycosis in which hyperthermia proved effective is reported. The patient was a 56-year-old male bean curd maker who, without any previous history of minor trauma, developed on the extensor side of the left upper arm an eczematous lesion that underwent gradual radial expansion. The lesion showed a well-defined, 7×10 cm infiltrated erythematous plaque with the central area healed and, at the upper and lower borders, adherent scales and crusts on the surface. Histological examination revealed granulomatous changes in the dermis, as well as sclerotic cells within giant cells and microabscesses. On culturing,Fonsecaea pedrosoi was isolated. The patient was treated with disposable chemical pocket warmers, which were secured over the lesion with a rather tight elastic bandage, so that they kept the affected area warm for 24 hours a day. After a month of such hyperthermic treatment, the erythema and infiltration had decreased considerably, and microscopic examination and culture of the crusts both yielded negative results. Examination of biopsy specimens of the lesion after the third month showed that it had cicatrized. The treatment was stopped after 4 months, and no relapse occurred. We also summarize the published results of local hyperthermic treatment of chromomycosis in Japan.  相似文献   
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When trying to improve antibiotic processes that are already high yielding, real industrial problems have to be faced. These include the use of organisms with non-ideal growth and recombination cycles, and problems of scale up from the laboratory to the main production plant. Many of the principles derived from academic studies have to be radically modified before they can be applied in the industrial context. These issues are a challenge to those who genuinely wish to contribute to the solution of industrial problems.  相似文献   
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Three sandwich-ELISAs, two of which are commercially available (Tecra and Locate), and one developed at the Veterinary Sciences Division, Stormont and a 3-step culture protocol, were compared for the detection of salmonella in 1000 animal specimens. Eight hundred and fifty of these were new submissions and the remainder were frozen portions from specimens previously shown to contain salmonellas by culture. The incidence of ELISA false-negative and false-positive results was highest for the Stormont and Locate kits respectively although the differences in sensitivity and specificity between the three ELISAs was not statistically significant. On 16 occasions all ELISA methods indicated the presence of salmonellas when none were isolated by initial culture, eight of these specimens contained salmonellas when reinvestigated by culture.  相似文献   
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