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Joyce Wright 《BMJ (Clinical research ed.)》1937,1(3970):259-260
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Jeffrey L. Clark Joyce L. Fuller 《Biochemical and biophysical research communications》1976,73(3):785-790
Putrescine and other amines are known to rapidly reduce or prevent increases in ornithine decarboxylase activity in a number of systems. We have confirmed reports of a nondialyzable inhibitor of the enzyme in serum-starved H-35 hepatoma cells exposed to serum and putrescine. In contrast, we detected little if any nondialyzable inhibitor in serum-limited Swiss 3T3 cells treated similarly. Also, evidence of a dissociable enzyme-inhibitor complex was found in H-35 cells but not in 3T3 cells. These results suggest that assimilated putrescine can reduce ornithine decarboxylase activity by mechanisms not involving a macromolecular inhibitor. 相似文献
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David M. Smyth Nicholas S. Horne Elli Ronayne Rachel V. Millar Patrick W. S. Joyce Maria Hayden‐Hughes Louise Kregting 《Restoration Ecology》2020,28(3):645-654
Ostrea edulis was once prolific throughout Europe and considered as the continent's native oyster. However, O. edulis currently exists in small fragmented assemblages where natural unaided recovery is rarely encountered. This research identified the small semi‐enclosed sea Lough of Strangford on the northeast coast of Northern Ireland as one of the few locations within Europe where the native oyster displayed gregarious natural rejuvenation. On close examination, four influential parameters appeared to assist in concentrated settlement; raised topographical cultch formations, shell coverage, the number of fecund in situ adults, and site protection. If these components were to be combined and managed as part of reintroduction and restoration initiatives, high‐density settlements and self‐sustaining populations may be possible. The research also identified that unregulated harvesting of intertidal O. edulis assemblages has the potential to seriously hinder natural recoveries. Indeed, the findings suggest that a review of policy in regards to intertidal hand gathering is necessary. However, naturally occurring high‐density settlements recorded during this research should be inspirational to all involved in the restoration of the native oyster. 相似文献
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Lees K. J. MacNeil M. A. Hedges K. J. Hussey N. E. 《Reviews in Fish Biology and Fisheries》2021,31(1):25-51
Reviews in Fish Biology and Fisheries - Mark-recapture approaches are among the most powerful fisheries methods for estimating demographic parameters relating to survival, components of mortality... 相似文献