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Adams M 《Science (New York, N.Y.)》1973,180(4088):840-842
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Smither-Kopperl ML 《Science (New York, N.Y.)》2002,298(5600):1891-1892
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Shimojima M Miyazawa T Ikeda Y McMonagle EL Haining H Akashi H Takeuchi Y Hosie MJ Willett BJ 《Science (New York, N.Y.)》2004,303(5661):1192-1195
Feline immunodeficiency virus (FIV) induces a disease similar to acquired immunodeficiency syndrome (AIDS) in cats, yet in contrast to human immunodeficiency virus (HIV), CD4 is not the viral receptor. We identified a primary receptor for FIV as CD134 (OX40), a T cell activation antigen and costimulatory molecule. CD134 expression promotes viral binding and renders cells permissive for viral entry, productive infection, and syncytium formation. Infection is CXCR4-dependent, analogous to infection with X4 strains of HIV. Thus, despite the evolutionary divergence of the feline and human lentiviruses, both viruses use receptors that target the virus to a subset of cells that are pivotal to the acquired immune response. 相似文献
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Among Aboriginal peoples in Canada, mercury pollution has had an impact on social and cultural well being, both at the community level and among individual members within the community, even when there are no provable direct health effects. This paper explores the link between mercury pollution and social and cultural disruption in Canadian Aboriginal communities. It demonstrates how factors such as Aboriginal holistic concepts of environment and health, perceptions, and difficulties in communication can contribute to indirect impacts of mercury pollution on health and well being. It is argued that, given the blood mercury levels among Canadian Aboriginal peoples, social and cultural impacts of mercury pollution present a much greater problem than do the direct clinical effects of exposure. 相似文献
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The endemic Seram cockatoo, Cacatua moluccensis, was placed on Appendix I of CITES in response to declining trade statistics but in the absence of population data. We conducted population surveys and collected data on habitat structure at seven sites on Seram in 1998. Cockatoo densities ranged from 0.93 to 17.25 birds/km2 and averaged 7.9 birds/km2 across sites. We classified habitat into three types but found that cockatoo densities did not correspond closely to habitat differences across sites. Cockatoo abundance was significantly associated with presence of potential nest trees and strangling figs. Analysis of forest cover and landuse indicates that while most of the island is still covered in lowland forest, only 14% of these forests are protected and almost half the island is classified as logging concession. Conservation recommendations include better information and enforcement of laws protecting Seram cockatoos and resolution of boundary conflicts between parks and logging concessions. 相似文献