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J E Blake N O Nielsen W P Heuschele 《Journal of the American Veterinary Medical Association》1990,196(7):1141-1143
The severity of lymphoproliferative disease associated with malignant catarrhal fever was extremely variable among 25 animals at the San Diego Wild Animal Park. Severe lymphoproliferative disease was seen in 3 of 10 Formosan Sika deer (Cervus nippon taiouanus), 3 of 6 Indian Axis deer (Cervus a axis), 3 of 6 Barasingha deer (Cervus d duvauceli), and 1 of 3 Nilgai (Boselaphus tragocamelus). Two Sika deer and 2 Barasingha deer had lesions morphologically indistinguishable from lymphosarcoma. Our findings were consistent with the hypothesis that alcelaphine herpesvirus-1 has oncogenic potential. 相似文献
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A kinetic study of the acetylation of cellulose, hemicellulose and lignin components in wood 总被引:1,自引:0,他引:1
The rates of acetylation of Deal, Larch, Southern Yellow Pine and Sitka Spruce using acetic anhydride in xylene have been measured and compared with the composition of the woods. Although these woods have similar macroscopic characteristics, the correlation between rate of acetylation and composition remains unclear, although the holocellulose may play a role in converting the hydrophilic hydroxyl groups to hydrophobic acetyl groups. The rate of acetylation of Larch at 373 K was insignificant but the other wood samples showed significant acetylation at this temperature. The activation energies for the acetylation process suggest that several routes may be involved. 相似文献
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The impact of drought conditioning on the ability of eight-week-old jack pine (Pinus banksiana Lamb.) seedlings to withstand drought was assessed. Two progressive cycles of drought conditioning significantly increased the survival of seedlings subjected to a subsequent prolonged drought. The in vivo accumulation of several root membrane proteins during drought conditioning was correlated with an increase in seedling survival. A group of root proteins, ranging in molecular mass from 43 to 47 kDa, increased accumulation during one cycle of drought conditioning and to a lesser extent during two cycles of drought conditioning. The accumulation of several low molecular mass membrane and soluble proteins also increased during drought conditioning, suggesting that these proteins may play an important role in the enhancement of drought tolerance. In vitro translation studies showed a general increase in the abundance of protein products encoded by mRNAs from drought-conditioned seedlings. Although the majority of the in vitro translation products appeared in both control and drought-conditioned seedlings, one mRNA encoding a 15 kDA translated protein was more prominent during the second cycle of drought conditioning. 相似文献
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C. R. C. Sheppard K. Matheson J. C. Bythell P. Murphy C. Blair Myers B. Blake 《水产资源保护:海洋与淡水生态系统》1995,5(4):277-298
- 1 The nature and distribution of the coastal and shallow marine habitats of Anguilla in the Caribbean were examined using aerial photography coupled with extensive ground truth information.
- 2 The objective was to develop an accurate method of marine habitat mapping for the analysis of the marine ecosystem in order to develop a procedure for marine and coastal resource management.
- 3 This paper describes the method which was adopted as well as the biological results.
- 4 It is concluded that the management and sustainable use of the natural resources may be improved as a result of accurate habitat mapping.