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71.
Immaculateness, a novel measure of bird plumage quality, defined as the regularity of the borders of a coloured patch of feathers, and the uniformity of the colour within the patch, tends to decline as a result of feather wear and damage. If it declines more quickly amongst birds in poor condition, it has the potential to act as an honest signal of individual quality and therefore be subject to social and sexual selection. We scored plumage immaculateness in shelducks Tadorna tadorna, based on the absence of white feathers in the red-brown chest band and the evenness of the band's border. We monitored body condition and plumage quality in birds at feeding sites in the Severn Estuary (UK) during the early breeding season when females were forming eggs, and later in the season when chicks arrived. Drakes had more immaculate chest bands than ducks. At preferred feeding sites, drakes were more immaculate, and birds of both sexes were in better body condition. Birds with more immaculate plumage tended to mate assortatively at preferred sites and were more likely to produce a brood that survived the journey to the feeding areas. Immaculateness could therefore be an honest signal of parental quality. Although our evidence is only correlational, we suggest that plumage immaculateness indicates the ability to establish and maintain control over the best breeding sites and feeding territories in the face of competition with other shelducks.  相似文献   
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Challenging the neurocentric view of neuromuscular synapse formation   总被引:3,自引:0,他引:3  
Ferns M  Carbonetto S 《Neuron》2001,30(2):311-314
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Cardiovascular disease (CVD) is an overall term that comprises a number of related pathologies, these include peripheral arterial disease, cerebrovascular disease, coronary heart disease (CHD), venous thromboembolism, and rheumatic and congenital heart diseases. Fatty acids in the diet have been reported to affect CVD. The OPG/RANKL/RANK system appears to have a role in CVD outcomes. However, there have been few studies on the impact of diet-gene interaction for effects of fatty acids consumption on the OPG/RANKL/RANK system in CVD. This review focuses on the effects of fatty acids on OPG/RANKL/RANK in CVD.  相似文献   
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Molecular Biology Reports - Tumor necrosis factor alpha (TNF-α) is a pro-inflammatory cytokine involved in the regulation of the immune system and potentially the progression of cervical...  相似文献   
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