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541.
Dove A 《Nature medicine》2002,8(8):770-771
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A significant number of moribund and dead lobsters Homarus americanus were reported to New York state authorities by lobster fishers in Long Island Sound (LIS) during the summer of 2002. Morbid lobsters were characterised by an orange discolouration of the abdomen, lethargy, an excess of epibionts and poor post-capture survival. On necropsy, severe extensive multifocal or diffuse mineralised granulomatous inflammation of the gills and antennal glands was the most striking pathology. In the gills, granulomas often occluded the lumen of filaments, resulting in congestion, ischemia and coagulative necrosis of gill tissues. In the antennal glands, granulomas were concentrated along the border between the coelomosac and labyrinth. No significant pathogens were recovered from diseased individuals. In prechronic individuals, however, it was evident that granulomas were focused around calcium carbonate (aragonite) crystals. This disease may result from anomalously high sea-bottom temperatures in LIS (approximately 23 degrees C) during the summer of 2002 and associated disruptions of the calcium chemistry of lobsters in favour of deposition of minerals in soft tissues. The ultimate cause of death of affected lobsters is probably respiratory failure due to reduced effective surface area of the gills, exacerbated by hypermetabolic temperatures and an abundance of epibionts. 相似文献
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Pomphorhynchus heronensis and restricted movement of Lutjanus carponotatus on the Great Barrier Reef
Samples of Lutjanus carponotatus (Lutjanidae) from reef flat (shallow) and reef slope (deep) sites around Heron and Wistari reefs on the southern Great Barrier Reef were examined for Pomphorhynchus heronensis (Acanthocephala). Individual fish from the reef slope had 0-9 (2.6) worms as compared with 1-122 (39.6) worms for individuals from the reef flat (P < 0.0001). Other variables (year, season, size of fish) made little contribution to the variation. Reef flat and reef slope sites were separated by as little as 300 m. These results imply both that the fish have very limited local movement and that transmission of the parasite is concentrated locally. 相似文献
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Milking the genome for profit 总被引:5,自引:0,他引:5
Dove A 《Nature biotechnology》2000,18(10):1045-1048
Despite recent accomplishments, significant challenges remain before cloning can become a routine part of transgenic animal production. 相似文献