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排序方式: 共有237条查询结果,搜索用时 15 毫秒
231.
Wolkers H van Bavel B Ericson I Skoglund E Kovacs KM Lydersen C 《The Science of the total environment》2006,370(1):70-79
Blubber samples from 17 adult, male walruses were sampled in eastern Svalbard and analyzed for chlorinated and brominated contaminants. A wide range of contaminants were detected, including PCBs (mean 2000; 95% range 1165-4005 ng/g lipid), DDE (mean 100: 95% range 50-310) ng/g lipid), chlordanes (mean 2500; 95% range 1347-5009) ng/g lipid, toxaphenes (mean 80; 95% range 51-132 ng/g lipid) and polybrominated diphenyl ethers (PBDEs) (mean 15 ng/g; 95% range 9-27 ng/g lipid). PCB and DDE levels were substantially lower than those of animals sampled 10 year earlier in this area, confirming a decreasing trend for these compounds in the Arctic. However, compared to other recently sampled marine mammals from Svalbard, walruses showed relatively high PCB and chlordane levels although they had lower levels of DDE, toxaphenes, and PBDEs, possibly due to species- and location-specific differences in exposure and metabolism. The range in contaminant levels found within the sample group was vast, despite the fact that the animals investigated were all adult males from the same location. The PCB pattern in highly contaminated animals was different from that in animals with low levels of contamination, with relatively more persistent PCBs in the highly contaminated group. This suggests that the more contaminated animals were feeding at higher trophic levels; possibly targeting seals in addition to mollusks as their prey. This suggestion was reinforced by the fatty acid profiles of the inner blubber layer of walruses with low versus high contaminant levels, which suggested different diets for the two groups. 相似文献
232.
John R.P. French III Richard G. Stickel Beth A. Stockdale M. Glen Black 《Journal of Great Lakes research》2010
Diporeia hoyi and Mysis relicta are the most important prey items of slimy sculpins (Cottus cognatus) in the Great Lakes. Slimy sculpins were collected from dreissenid-infested bottoms off seven Lake Michigan ports at depths of 27–73 m in fall 2003 to study their lake-wide diets. Relatively large dreissenid biomass occurred at depths of 37- and 46-m. Quagga mussels (Dreissena bugnesis) composed at least 50% of dreissenid biomass at Manistique, Saugatuck, and Sturgeon Bay. Mysis accounted for 82% of the sculpin diet by dry weight at eastern Lake Michigan while Diporeia composed 54–69% of the diet at western Lake Michigan and dominated the diets of slimy sculpins at all sites deeper than 46 m. In northern Lake Michigan, this diet study in new sites showed that slimy sculpin consumed more prey with low energy contents, especially chironomids, than Mysis and Diporeia in shallow sites (depth <55 m). We recommend diet studies on sedentary benthic fishes to be conducted along perimeters of the Great Lakes to observe changes in their diets that may be impacted by changing benthic macroinvertebrate communities. 相似文献
233.
High Saturated Fat Diet Alters the Lipid Composition of Triacylglycerol and Polar Lipids in the Femur of Dam and Offspring Rats 下载免费PDF全文
Paula M. Miotto Laura M. Castelli Foyinsola Amoye Wendy E. Ward Paul J. LeBlanc 《Lipids》2015,50(6):605-610
Previous work has shown that dietary lipids alter femur lipid composition. Specifically, we have shown that exposure to high saturated fatty acid (SFA) diets in utero, during suckling, or post‐weaning alters femur total lipid composition, resulting in higher percent bone mass in males and females and bone mineral density (BMD) in female offspring with no effect on bone mineral outcomes in dams. Comparatively, high n‐3 polyunsaturated fatty acid (PUFA) diets increase femur polar (PL) lipid n‐3 content, which has been associated with increased bone mineral content and strength. However, the extent that PL or triacylglycerol (TAG) lipids change with high SFA diets is unknown. The current investigation examined the influence of a high SFA diet (20 % lard by weight) on femur PL and TAG lipid composition in 5‐month old female Wistar rats (fed high SFA diet from age 28 days onwards; dams) and their 19‐day old offspring (exposed to high SFA in utero and during suckling; pups). High SFA exposure resulted in increased monounsaturates and decreased n‐3 and n‐6 PUFA in the TAG fraction in both dams and pups, and higher SFA and n‐6:n‐3 ratio in dams only. The PL fraction showed decreased n‐6 PUFA in both dams and pups. The magnitude of the diet‐mediated responses, specifically TAG 18:1 and PL n‐6 PUFA, may have contributed to the previously reported altered BMD, which was supported with correlation analysis. Future research should investigate the relationship of diet‐induced changes in bone lipids on bone structure, as quantified through micro‐computed tomography. 相似文献
234.
Steaks from corn-fed and barley-fed beef were characterized by a trained panel, which rated corn-fed beef higher (p<0.05) for tenderness attributes and overall flavor intensity. Canadian consumers preferred (p<0.01) cooked and raw steaks from barley-fed beef, while Mexican consumers showed no preference (p>0.05) for either type of finished beef. Japanese consumers showed a preference (p<0.05) for the appearance of raw barley-fed steaks but a preference for cooked corn-fed steaks (p<0.05). No differences (p>0.05) were observed for Warner-Bratzler shear, marbling scores, cooking losses or Hunter colorimeter values. There was a trend for higher concentrations (p<0.08) of the saturated fatty acids in the barley treatment, but no differences (p>0.10) in mono or polyunsaturated fatty acids. 相似文献
235.
山东省居民膳食营养状况调查 总被引:1,自引:0,他引:1
目的 了解山东省居民膳食营养状况。方法整群随机抽样,用称重法和24h回顾法进行连续3d膳食摄入调查。结果谷类摄入量城市比农村少68.6g,动物性食物摄入量城市比农村多19、7g。能量、蛋白质、脂肪、糖类、维生素C和钠的摄入量城市低于农村,城市和农村比较分别少273.2kcal、3、1g、1.9g、60g、8.1mg、463.6mg。膳食结构仍以谷类食物为主。结论 山东省居民膳食营养存在不平衡现象,需要加强营养教育,引导居民合理膳食。 相似文献
236.
Weekday sunlight exposure,but not vitamin D intake,influences the association between vitamin D receptor genotype and circulating concentration 25‐hydroxyvitamin D in a pan‐European population: the Food4Me study 下载免费PDF全文
Ulrich Hoeller Christina P. Lambrinou George Moschonis Anna L. Macready Rosalind Fallaize Manuela Baur Franz F Roos Igor Bendik Keith Grimaldi Santiago Navas‐Carretero Rodrigo San‐Cristobal Peter Weber Christian A. Drevon Yannis Manios Iwona Traczyk Eileen R. Gibney Julie A. Lovegrove Wim H. Saris Hannelore Daniel Mike Gibney J. Alfredo Martinez Lorraine Brennan Tom R. Hill John C. Mathers 《Molecular nutrition & food research》2017,61(2)
237.