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61.
The impact of ticks on pheasant territoriality   总被引:1,自引:0,他引:1  
Pheasants are competent reservoir hosts for the Lyme disease spirochaete, Borrelia burgdorferi s.l., and carry large, but highly over-dispersed, infestations of the vector ticks, Ixodes ricinus . The effects of experimental reduction of tick infestation levels on the survival and territorial behaviour of male pheasants were studied. Over three years in two woodlands in southern England, birds were marked individually and half were fitted with a slow-release acaricide, which substantially reduced their tick burdens from March to August. Acaricide treatment affected reproductive success but had no discernible impact on the survival rates of male pheasants. The degree of wattle inflation by males, an indicator of territorial status and a correlate of harem acquisition, was significantly greater among treated males. In each year, a significantly higher proportion of treated (overall 44%) than control (22%) males acquired harems. Males that acquired females ranged over small areas on field edges. By contrast, those with no females ranged more widely in woods and the adjoining fields, increasing their exposure to questing ticks. The relative contribution of such roving males to tick-borne pathogen transmission may thus increase.  相似文献   
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Using the monkey model previously developed, we investigated the long-term effects of retrobulbar hematoma-induced retinal ischemia on functional vision and retinal histology. In this experimental model, ischemic periods of up to 120 minutes did not cause permanent visual deficits, as measured by flashed evoked visual potentials. Similarly, retinal histology showed no evidence of ischemic injury. From this we conclude that blindness after blepharoplasty is not due to retrobulbar hematomas alone and that additional predisposing factors are involved. The most likely additional factor is preexisting occult vascular ocular pathology.  相似文献   
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The relationship between prominent visual imagery and emotion within dreams was investigated in relation to E. Hartmann's (1996) contextualizing image (CI) theory and M. Seligman and A. Yellen's (1987) dual imagery theory. Fifty-nine students recorded dreams over a 2-week period and submitted 115 dreams for analysis. Participants recorded ratings of emotion type and emotion intensity in each scene. Prominent visual images were identified and scored for intensity and detail by independent judges. As hypothesized from Hartmann's theory, there was a significant positive relationship between CI intensity and emotion intensity in the CI scene, emotion intensity generally peaked in the CI scene, and dreams containing a CI had higher overall ratings of emotion intensity than non-CI dreams. The result for the correlation of detail of prominent imagery with emotion was inconclusive, with a low positive correlation across CI scenes. This raises the possibility that the CI is not a unitary construct. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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T. P. Young 《Oecologia》1987,71(3):436-438
Summary I report here longer thorns induced by large mammal herbivory on the tree Acacia depranolobium. I compared trees that had been browsed by domestic goats to trees protected from goat browsing. Thorns on browsed branches within the reach of goats (<125 cm above the ground) were significantly longer than thorns from higher branches on the same browsed trees, and significantly longer than branches at similar heights on unbrowsed trees. It appears that increased thorn length was an induced response to large mammal herbivory in Acacia depranolobium, both among and within individual trees.  相似文献   
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K Ozawa  N Young 《Journal of virology》1987,61(8):2627-2630
The major capsid and noncapsid proteins of the pathogenic parvovirus B19, propagated in vitro, were detected by sodium dodecyl sulfate-polyacrylamide gel electrophoresis, immunoprecipitation, and immunoblot of the erythroid fraction of infected human bone marrow cell cultures. There were two capsid proteins of 58 kilodaltons (kDa; the major species) and 84 kDa (the minor species). Newly synthesized capsid viral proteins were present in the supernatants of infected cultures. The major noncapsid protein of 77 kDa was localized to the nucleus.  相似文献   
70.
Insulin and insulin-related growth factor 1 (IGF-1) increase by 1.5-1.6-fold the rate of [3H]leucine incorporation into protein in primary monolayer cultures of chick-embryo fibroblasts (CEF); half-maximal hormone concentrations are 10 and 0.25 nM respectively. To investigate the mechanism of this effect, a rapid method is used to prepare a lysate from CEF which is active in protein synthesis. Lysate derived from cells treated for 30-150 min with insulin synthesized protein at 1.8-3.0-fold greater rate than did controls; the increased rate persisted for 20 min in vitro. Pactamycin (0.5 microM), an inhibitor of peptide-chain initiation, inhibited protein synthesis by 50% in lysates derived from insulin-treated and control cells. Thus insulin and IGF-1 cause an increase in the protein-synthesis rate in vivo, which persists in cell-free protein-synthesizing lysates of CEF.  相似文献   
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