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31.
A Preliminary Study of Silver Sodium Zirconium Phosphate Polyurethane Foam Wound Dressing on Wounds of the Distal Aspect of the Forelimb in Horses 下载免费PDF全文
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户用分布式光伏对农户收入影响具有长期性,如何发挥分布式光伏在乡村振兴战略中的作用需进一步探索。本文以户用分布式光伏为例,利用中部地区Y县2014—2019年农户追踪数据,运用双重差分法,分析户用分布式光伏对农户收入的影响,探讨户用分布式光伏对农户收入影响的作用机制。结果表明,2014—2019年农户收入大幅度提升,其中建光伏农户的人均收入增长幅度大于未建光伏农户,户用分布式光伏使农户人均收入提高25.4%,其中经营性收入、财产性收入分别提高74.4%和444.5%,而工资性收入降低45.3%。户用分布式光伏是通过减少非农劳动时间和缩短非农就业空间距离降低农户工资性收入,增加经营性收入,从而影响人均收入。进一步分析发现,户用分布式光伏对非中心村农户的工资性收入和经营性收入影响大于中心村农户,劳动力能力越强的农户经营性收入上升幅度越大,工资性收入下降幅度越小。因此,建议统一维护光伏设施,促进劳动力要素有效配置;并依据劳动能力差异分层分配股份,降低劳动能力强的农户对政府补贴的依赖;另外,创新光伏产业发展模式,拓宽光伏产业增收渠道。 相似文献
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M. J. SÁNCHEZ-MUROS L. GARCÍA-REJÓN J. A. LUPIÁÑEZ M. DE LA HIGUERA 《Aquaculture Nutrition》1996,2(4):193-200
The influence of long-term administration of high-carbohydrate/low-protein and high-fat/non-carbohydrate diets were studied in relation to kinetic behaviour of glucose 6-phosphate dehydrogenase in liver and kidney of rainbow trout. In all cases studied, the saturation curves of these enzyme showed typical hyperbolic kinetics without evidence of sigmoidicity. After 30 days of feeding with a high-fat diet (170 g kg?1), there was a significant decrease in Vmax and specific activity (45%) as well as catalytic efficiency (39%) without changes in Km or activity ratio of hepatic glucose 6-phosphate dehydrogenase. These changes agree more with a clearly decreased cell concentration than with an inhibition of the pre-existing enzyme. The administration of a high-carbohydrate diet (60 g kg?1), contrary to what was previously thought, decreased Vmax by 21% and specific activity and catalytic efficiency by 30%, without significant changes in the other kinetic parameters of the hepatic enzyme. The kinetic behaviour under these nutritional conditons was due to the rejection of this diet by the fish and thus could be considered a low-feeding situation. On the other hand, no variations in the kinetics of renal glucose 6-phosphate dehydrogenase were found, clearly demonstrating that in this organ, the pentosephosphate pathway showed no adaptive response related to fattyacid and other lipid synthesis. The activity of the renal enzyme was consistently half that of the hepatic enzyme. 相似文献
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Recently Infectious Bursal Disease Virus isolates have been described in USA displaying an antigenic drift. Many of the new isolates were very virulent for chickens. In several European countries severe outbreaks of Gumboro disease have also been reported from vaccinated and non-vaccinated flocks. Since vaccinated SPF birds were shown to be protected against challenge infection with the new isolates under laboratory conditions, a more detailed investigation of the European isolates is wanted. The similarity between the European and US field situation got us to use a panel of monoclonal antibodies (MCAs) previously applied to characterize US strains for testing European isolates. An antigen capture ELISA has been carried out directly on bursa homogenates of chickens form the field. One European (F52/70) and two US (Var. E and GLS-5) strains have been included as reference viruses. From the results presented here it can be concluded that the European isolates (Netherlands, France, UK, Germany, Jugoslavia and Spain) did not undergo the same antigenic drift as the US strains. A more extensive analysis of the isolates will be done to elucidate their role for disease outbreaks. 相似文献
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Summary An experiment was conducted to develop a method for monoploid seedling detection which is more efficient than making cytological examinations of twin seedlings. A recessive seedling marker gene (basal stem color) was used to detect parthenogenesis in female plants. Out of 10 seedlings showing the marker character, 9 were monoploid as expected. The frequency of parthenogenesis among single seedlings was approximately 1 seedling in 2,400. The marker gene technique increases the efficiency of cytological examination from approximately 1 or 2% to 90%.Florida Agricultural Experiment Station Journal Series No 3681 相似文献