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61.
Grey seals on the West Hoyle Bank feed on a variety of fish and have a high incidence of dermal lesions, often associated with emaciation and nematode parasite infection. Corynebacterium phocae has been isolated from an active lesion. The significance of large numbers of seals in the Dee Estuary bearing lesions is discussed and the occurrence of seals with lesions elsewhere in British waters is reviewed. No evidence was found to associate the dermal lesions with any environmental factor and it is probable that lesions develop as a result of infection of minor wounds. 相似文献
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A Study of the Aminoacyl-sRNA Synthetases of Phaseolus vulgaris in Relation to Germination 总被引:3,自引:2,他引:1 下载免费PDF全文
Optimum conditions for the extraction and assay by ATP-pyrophosphate exchange of the aminoacyl-sRNA synthetases of the various tissues of french bean (Phaseolus vulgaris) seeds and seedlings are described. Extracts of plumules, after passage through Sephadex G-25, were assayed for synthetase activity using an amino acid mixture as substrate, when a 30 to 100-fold stimulation of exchange above the endogenous level was obtained. This marked enhancement of exchange by added amino acids is largely attributed to the use of dilute extracts. 相似文献
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Summary The techniques of light and electron microscopy have been employed in a study of the protective coverings of the egg of Drosophila melanogaster. Data obtained during this investigation suggest the involvement of the follicle cells, in the production of one of these coverings and justify its classification as a secondary coat. The secondary coat of D. melanogaster is highly organized and has been divided into three Zones (I, II, IIII). The follicle cells enveloping the oocyte exhibit two phases of secretory activity each involving hypertrophy of the Golgi complex and rough endoplasmic reticulum, and the production of protein and polysaccharide components. The first phase concerns the elaboration of the material which gives rise to the homogeneous lamina referred to as Zone I. The second results in the release of an electron dense component which becomes organized into two laminae separated by struts or pillars; this construction is referred to as Zone II. At the completion of this secretory phase, the follicle cells assume a squamous morphology and a third Zone, composed of a homogeneous substance, appears between the follicle cells and Zone II.This investigation was supported by grant GM-08776 to one of us (EA) from the National Institutes of Health, United States Public Health Service. 相似文献
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R. Morley D. W. Eccleston C. P. Douglas W. E. J. Greville D. J. Scott J. Anderson 《BMJ (Clinical research ed.)》1970,3(5720):442-443
Three cases of xylene poisoning occurred after prolonged inhalation of paint fumes. Analysis showed that xylene comprised more than 90% of the solvent in the paint, the total solvent comprising 34% of the paint by weight. One patient was dead on admission, while the other two recovered after at least 15 hours'' loss of consciousness. Both patients had transient liver cell damage, and one temporary impairment of renal function. 相似文献
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