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排序方式: 共有347条查询结果,搜索用时 218 毫秒
1.
Nutritional Contribution of Biofloc within the Diet of Growout and Broodstock of Litopenaeus vannamei,Determined by Stable Isotopes and Fatty Acids 下载免费PDF全文
Edén Magaña‐Gallegos Rodrigo González‐Zúñiga Gerard Cuzon Miguel Arevalo Eduardo Pacheco Manuel A. J. Valenzuela Gabriela Gaxiola Elisa Chan‐Vivas Korinthia López‐Aguiar Elsa Noreña‐Barroso 《Journal of the World Aquaculture Society》2018,49(5):919-932
The relative contributions of feed sources were determined through the isotopic signal (δ13C and δ15N) and fatty acid profile of feed items, shrimp muscle, and eggs of Litopenaeus vannamei reared in a biofloc system. In the growout phase, the isotope analysis showed the biofloc particle size class ≥250 μm contributed 55–100%; size ≥50 < 250 μm contributed 0–22%; and artificial feed contributed 0–45%. Principal component analysis applied to fatty acid profiles showed that biofloc ≥250 μm and artificial feed were the most important items in shrimp growout. For the egg production, isotope analysis suggested that the most important feed sources according to their relative contributions were polychaetes (0–100%), followed by artemia biomass (0–86%) and semi‐moist feed (0–66%), with lower contributions from squid, mussel, and the muscle of L. vannamei broodstock that had been cultured in biofloc. In terms of fatty acids, the most important items were artemia, polychaetes, and semi‐moist feeds. This work clarified the importance of feed sources for shrimp during culture in biofloc systems and during reproduction. Analysis of stable isotopes and fatty acids can be successfully used to trace the assimilation of nutrients during the nutrition of shrimp. 相似文献
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Karine Gendron Christine Goepfert Elisa Linon Horst Posthaus Caroline F. Frey 《The Canadian veterinary journal. La revue veterinaire canadienne》2015,56(3):267-271
A young adult Labrador retriever dog was presented for surgical debulking of hepatic alveolar echinococcosis. Computed tomography detected hepatomegaly with multiple large cavitary masses with extension of tissue from a lesion wall into the caudal vena cava and numerous nodules in all lung lobes. Following euthanasia, histology confirmed parasitic vesicles with granulomatous reaction in all lesions, and polymerase chain reaction (PCR) established the causative agent to be Echinococcus multilocularis. This report is the first to present imaging features of pulmonary E. multilocularis granulomata in a dog. 相似文献
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Elisabete Yurie Sataque Ono Elaine Cunha Moreno Mario Augusto Ono Carolina Nachi Rossi Gervásio Hitoshi Saito Édio Vizoni Yoshitsugu Sugiura Elisa Yoko Hirooka 《European journal of plant pathology / European Foundation for Plant Pathology》2011,131(4):653-660
In this study the effect of different cropping systems and crop successions was evaluated on natural Fusarium sp. contamination and fumonisin levels in corn. The cropping systems consisted of a conventional and no-tillage area cultivated
with corn in the summer following either oats or fallow in the winter (2006 and 2007 growing seasons). In addition, the effect
of applying nitrogen fertilizer (0, 22.5, 45.0, 90.0 and 90.0 kg ha−1 nitrogen supplemented with potassium oxide) on fumonisin contamination was evaluated in the 2006 growing season. Fusarium sp. was detected in 90% samples in 2006 and in 100% samples in 2007. In both growing seasons, no-till corn following oats
showed the highest mean fumonisin levels and differed significantly (P < 0.05) from all the others (2006) and from conventional till corn following either oats or fallow in the winter (2007).
Fumonisin levels ranged from 0.13 to 19.52 μg g−1 (mean 6.97 μg g−1) and from 3.70 to 7.75 μg g−1 (mean 6.29 μg g−1) in no-till corn following oats from the 2006 and 2007 growing seasons, respectively. Plots treated with 0 kg ha−1 and 22.5 kg ha−1 nitrogen showed the highest mean fumonisin levels and differed significantly from those with 45.0 and 90 kg ha−1 nitrogen. Fumonisin levels correlated negatively (P < 0.05) with the nitrogen fertilization rates. Although no-till is advantageous from a soil conservation standpoint, it may
enhance the potential for fumonisin contamination in corn. 相似文献
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OBJECTIVES: To investigate time patterns of compliance with nutrient goals recommended by the World Health Organization (WHO). DESIGN: A single aggregated indicator of distance from the key WHO recommendations for a healthy diet is built using FAOSTAT intake data, bounded between 0 (maximum possible distance from goals) and 1 (perfect adherence). Two hypotheses are tested for different country groupings: (1) whether adherence has improved over time; and (2) whether cross-country disparities in terms of diet healthiness have decreased. SETTING: One hundred and forty-nine countries, including 26 countries belonging to the Organisation for Economic Co-operation and Development (OECD) and 115 developing countries (including 43 least developed countries), with yearly data over the period 1961-2002. RESULTS: The Recommendation Compliance Index (RCI) shows significant improvements in adherence to WHO goals for both developing and especially OECD countries. The latter group of countries show the highest levels of the RCI and the largest increase over time, especially between 1981 and 2002. No improvement is detected for least developed countries. A reduction in disparities (convergence of the RCI) is observed only within the OECD grouping. CONCLUSIONS: Adherence to healthy eating guidelines depends on economic development. Diets are improving and converging in advanced economies, but developing and especially least developed countries are still far from meeting WHO nutrition goals. This confirms findings on the double burden of malnutrition and suggests that economic drivers are more relevant than socio-cultural factors in determining the healthiness of diets. 相似文献
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Elisa Brunelli Giulia Pinton Paolo Bellini Alberto Minassi Giovanni Appendino Laura Moro 《Fitoterapia》2009,80(6):327-332
The activity of 8-prenylapigenin (8-PA) and its 3'-methoxylated analogue isocannflavin B (IsoB) was investigated in estrogen-dependent T47-D and estrogen-independent MDA-MB-231 human breast cancer cell lines. 8-PA showed a biphasic effect on T47-D cell proliferation, while no significant effect was observed on MDA-MB-231 cells. Conversely, IsoB exhibited only an inhibitory effect on T47-D cell proliferation, accompanied by the appearance of an intense intracytoplasmic vacuolization of autophagic origin. Moreover, biochemical analysis showed that IsoB reduced Akt phosphorylation and p21Cip1 expression in T47-D cells. These data show that the prenylflavone moiety is a versatile platform for the induction and modulation of bioactivity. 相似文献
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Physiological Responses of Contrasting Rice Genotypes to Salt Stress at Reproductive Stage 总被引:1,自引:0,他引:1
Maria Elisa B.GERONA Marjorie P.DEOCAMPO James A.EGDANE Abdelbagi M.ISMAIL Maribel L.DIONISIO-SESE 《水稻科学》2019,26(4):207-219
Salinity is a major abiotic stress affecting plant growth and productivity. Considerable genetic variation is present in rice in response to salt stress, with higher sensitivity during early seedling and reproductive stage. In this study, physiological changes in leaves and developing panicles of rice genotypes(IR686, Sadri, Rc222, CSR28, IR670 and Pokkali) contrasting in salt tolerance at the reproductive stage were evaluated in greenhouse experiment under salt stress. The results showed that IR670 and the tolerant-check Pokkali maintained lower Na~+/K~+ ratio, less reduction in chlorophyll concentration, lower malondialdehyde(MDA) production, higher concentrations of reduced ascorbate(reduced AsA), higher proline accumulation and lower percentage reduction in pollen viability than the salt-sensitive genotypes under salt stress. The higher concentration of reduced AsA suggests an efficient ROS-scavenging system. Physiological measurements and pollen viability analysis revealed that Sadri(moderately tolerant at the seedling stage) is sensitive to salt stress at the flowering stage. The findings will be useful in breeding salt tolerant varieties at both seedling and reproductive stages by selecting appropriate genotypes and phenotypes. 相似文献