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Evidence for papillomaviruses in ocular lesions in cattle 总被引:3,自引:0,他引:3
Negatively stained preparations of various ocular lesions, generally considered to be precursors to bovine ocular squamous cell carcinoma, were subjected to electron microscopic examination for viruses. Lesions examined included five conjunctival plaques, an acanthotic lesion from an eyelid, 15 conjunctival papillomas, two papillomas of the eyelid and two keratinised elongated proliferative lesions of the eyelid (cutaneous horns). Eight lesions contained particles that resembled papillomaviruses. These consisted of a conjunctival plaque, five conjunctival papillomas, a papilloma of the eyelid and one of the samples of cutaneous horn. The particles were present in small numbers and were found only after prolonged search. The finding of these particles suggests that papillomavirus may be involved in the aetiology of bovine ocular squamous cell carcinoma. 相似文献
274.
Culicoides: biological vectors of Akabane virus 总被引:1,自引:0,他引:1
Akabane virus replicated in Culicoides nubeculosus and Culicoides variipennis after intrathoracic inoculation and was maintained in both species of midge for at least 9 days post-infection. The virus also replicated to high concentration in C. variipennis after oral infection and was transmitted through a membrane by this species of midge 7-10 days after infection. The experiments described in this paper provided the first definitive evidence that Culicoides spp. are able to act as fully competent vectors of Akabane virus. 相似文献
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A range of protein intakes (5 to 20 g protein/d) was achieved by feeding six diets containing 7 to 14½% protein to a total of 400 pullets for 10 weeks from 28 weeks of age. The same six diets and an additional diet with 16% protein were fed again for 10 weeks from 62 weeks of age. The resulting patterns of egg output were different at the two ages. The birds required more protein at the end of the laying year than at the beginning to sustain any given level of output. This difference in protein requirement was not accounted for by changes in body weight.
It is concluded that measurements of protein input‐output relationships made at one stage in the laying year do not form a satisfactory basis for predicting protein requirement at another stage. 相似文献
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Sensory evaluations of 2 cultivars of cantaloupe (Cucumis melo var. reticulatus) at the eating-ripeness stage indicated considerable variations in quality. Soluble solids, flesh firmness, rind resistance and volatile flavor components also varied. Mechanical devices for testing tissue texture correlated well with sensory evaluations. There was low correlation between total volatiles determined by gas chromatography and aroma. However, differences were noted in the production of volatile compounds between melons. Statistical analysis of the data indicated low correlation between eating-quality and soluble solids content. Sweetness was the most important attribute in the determination of eating-quality. 相似文献