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排序方式: 共有219条查询结果,搜索用时 31 毫秒
61.
62.
Auger C Gérain P Laurent-Bichon F Portet K Bornet A Caporiccio B Cros G Teissédre PL Rouanet JM 《Journal of agricultural and food chemistry》2004,52(16):5297-5302
The aim of this study was to evaluate the antiatherosclerotic effect of commercially available phenolic-rich extracts from grape seeds (ExGrape seeds, EGS; grape seed extract, GSE) and marc (ExGrape total, EGT) in cholesterol-fed hamsters and to investigate possible operating mechanisms. These extracts fed at a moderate dose mimicking two glasses of red wine per meal reduced plasma cholesterol (-11% on average) but did not affect plasma antioxidant capacity of hamsters. The extracts prevented the development of aortic atherosclerosis by 68% (EGS), 63% (EGT), and 34% (GSE). Elsewhere, in an ex vivo experiment using rat aortic rings, EGS (7 microg/mL) induced 77% endothelium-dependent relaxation, whereas EGT and GSE (30 microg/mL) induced 84 and 72%, respectively. These results suggests that phenolic extracts from grape seeds and marc are beneficial in inhibiting atherosclerosis by indirect mechanism(s). 相似文献
63.
Mutua Florence Lindahl Johanna Randolph Delia 《Tropical animal health and production》2020,52(2):859-870
Tropical Animal Health and Production - Consumers have a right to safer foods, and traceability is one approach to meeting their expectations. Kenya does not have an operational animal traceability... 相似文献
64.
Darren Kelly Valerie Lamb Florence Juvet 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2020,34(2):890-892
Idiopathic aplastic pancytopenia is an uncommon disease in dogs which results in pancytopenia and for which an immune-mediated etiology is suspected. A small number of affected dogs reported in the veterinary literature have responded to immunosuppressive medication but the prognosis generally is considered poor with a reported mortality rate of 80%. Reported response rates to immunosuppression alone in affected people are low with overall and complete responses of 65 and 10%, respectively. With the addition of eltrombopag, an orally available thrombopoietin receptor agonist, reported overall and complete response rates in people increase to 94 and 58%, respectively. Herein, we report the use of eltrombopag in a dog with idiopathic aplastic pancytopenia. Eltrombopag was started after no response was seen to treatment with prednisolone and cyclosporine. Complete remission was achieved after the addition of eltrombopag and was sustained after stopping the medication. 相似文献
65.
Fillet texture and muscle structure in brown trout (Salmo trutta) subjected to long-term exercise 总被引:1,自引:0,他引:1
Brown trout (Salmo trutta) (2.7 g initial mean weight) were reared in freshwater for 8 months at water velocities of <0.1 (control group), 1 or 2 body lengths per second (BL s?1) (exercise groups). Growth (body weight, body length and body width), muscle structure (muscle fibre diameter and width of myosepta) and flesh quality parameters (dry matter, muscle pH, collagen content and solubility, instrumental evaluation of texture) were measured at the end of the experiment. The body weight of fish at 1 BL s?1 was 22% higher than the control group. Muscle development was stimulated at 1 and 2 BL s?1, leading to a higher condition factor, greater body height and width, and muscle fibre hypertrophy (55 vs. 59.5 μm fibre diameter in the control and 2 BL s?1 groups respectively). Connective tissue and collagen were only slightly affected by exercise (no difference in collagen solubility, but a greater proportion of γ trimer and fewer α chains in the control compared with the exercised group). Flesh quality was affected, with greater dry matter content and lower post‐mortem pH in the 1 BL s?1 group compared with the control and 2 BL s?1 groups. The mechanical resistance of the raw fillets was slightly but significantly increased by exercise. The exercise‐related changes in muscle structure and texture are discussed. 相似文献
66.
67.
Florence Noël Daniel Prati Mark van Kleunen Andreas Gygax Daniel Moser Markus Fischer 《Biological conservation》2011,(1):602-609
In response to ongoing local extinction of species and the current biodiversity crisis, the number of reintroduction programs aiming to establish new populations of rare species in the wild has increased. However, only a small proportion of these programs has been planned and monitored scientifically and comparative multi-species studies are missing in this context. Therefore, the relative importance of factors involved in reintroduction success is poorly known. In 2007, we assessed population growth since introduction as a measure of establishment success of 25 wetland species (rare or extinct in the wild nationwide) and a total of 50 populations in Switzerland that had been introduced at seven restored sites with apparently adequate environmental conditions between 1997 and 2005. We related establishment success to 32 life-history traits of these species obtained from the BiolFlor database, to initial number of introduced plants (propagule pressure with 1–130 individuals introduced per population), and to the ecological distance between source sites and restored sites based on vegetation records. Our results clearly showed the importance of close ecological similarity between source and introduction sites for successful establishment of wetland species into restored pond habitats. In contrast, neither life-history traits nor propagule pressure were related to establishment success in our study. Based on our results, we strongly recommend enforcing ecological studies prior to reintroduction to accurately assess the suitability of restored sites. To unambiguously assess the key determinants of successful establishment, future reintroduction programs should be set-up according to experimental designs. 相似文献
68.
69.
Beltran WA Vanore M Ollivet F Nemoz-Bertholet F Aujard F Clerc B Chahory S 《Veterinary ophthalmology》2007,10(1):43-49
OBJECTIVE: To determine the incidence and describe the characteristics of cataracts and other ocular lesions found in two colonies of gray mouse lemurs (Microcebus murinus). ANIMALS STUDIED: A total number of 218 mouse lemurs (age range: 4 months-11 years) were included in this study. All individuals were property of the Muséum National d'Histoire Naturelle (France), and were housed either in Paris (colony #1: 75 animals examined), or in Brunoy (colony #2: 143 animals). METHODS: Ocular examinations were performed on all animals before and after pupil dilation, and included slit-lamp biomicroscopy and indirect ophthalmoscopy. In both colonies, a limited number of individuals were re-examined between several months and 2 years following the initial eye examinations. The eyes of five mouse lemurs with incipient or immature cataracts that died during this period were collected, and processed for routine histopathologic examination. RESULTS: A high incidence of cataracts was observed in both colonies (48% in colony #1; 21% in colony #2). Cataracts were predominantly bilateral, started in the anterior and/or posterior subcapsular area, and appeared to be slowly progressive. The earliest age at which lens opacities were observed was 3.5 years, and more than 50% of mouse lemurs over 7 years of age were diagnosed with cataracts. Complete cataracts led to blindness and were occasionally associated with other ocular lesions. CONCLUSION: We report a high incidence of acquired, slowly progressive, bilateral cataracts in two colonies of mouse lemurs (Microcebus murinus). Further studies need to be conducted to determine the cause of this disease in this species. 相似文献
70.
Charlène Heiniger Sébastien Barot Jean-François Ponge Sandrine Salmon Léo Botton-Divet David Carmignac Florence Dubs 《Pedobiologia》2014
Landscape fragmentation is a major threat to biodiversity. It results in the transformation of continuous (hence large) habitat patches into isolated (hence smaller) patches, embedded in a matrix of another habitat type. Many populations are harmed by fragmentation because remnant patches do not fulfil their ecological and demographic requirements. In turn, this leads to a loss of biodiversity, especially if species have poor dispersal abilities. Moreover, landscape fragmentation is a dynamic process in which patches can be converted from one type of habitat to another. A recently created habitat might suffer from a reduced biodiversity because of the absence of adapted species that need a certain amount of time to colonize the new patch (e.g. direct meta-population effect). Thus landscape dynamics lead to complex habitat spatiotemporal structured, in which each patch is more or less continuous in space and time. In this study, we define habitat spatial structure as the degree to which a habitat is isolated from another habitat of the same kind and temporal structure as the time since the habitat is in place. Patches can also display reduced biodiversity because their spatial or temporal structures are correlated with habitat quality (e.g. indirect effects). We discriminated direct meta-community effects from indirect (habitat quality) effects of the spatiotemporal structure of habitats on biodiversity using Collembola as a model. We tested the relative importance of spatial and temporal structure of habitats for collembolan diversity, taking soil properties into account. In an agroforested landscape, we set up a sampling design comprised of two types of habitats (agriculture versus forest), a gradient of habitat isolation (three isolation classes) and two contrasting ages of habitats. Our results showed that habitat temporal structure is a key factor shaping collembolan diversity. A reduced diversity was detected in recent habitats, especially in forests. Interactions between temporal continuity and habitat quality were also detected by taking into account soil properties: diversity increased with soil carbon content, especially in old forests. Negative effects of habitat age on diversity were stronger in isolated patches. We conclude that habitat temporal structure is a key factor shaping collembolan diversity, while direction and amplitude of its effect depend on land use type and spatial isolation. 相似文献