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21.
The effect of insulin on the ascorbate recycling system in the chicken liver was examined. First, insulin was injected subcutaneously into the chicken, and liver glutathione‐dependent dehydroascorbate reductase (GSH‐DHAR) activity was determined. Insulin increased liver GSH‐DHAR activity, but did not affect plasma and liver ascorbate concentration. Dehydroascorbate increased plasma and liver ascorbate levels, and liver GSH‐DHAR activity. However, distinct changes in plasma insulin level were not observed by dehydroascorbate injection. In addition, reduction of external dehydroascorbate in cultured chicken hepatocytes could not be observed in an insulin‐deprived culture, although the cells reduced external dehydroascorbate in a serum‐free culture with insulin. We concluded that insulin affects the ascorbate recycling system as an essential factor in the chicken liver.  相似文献   
22.
燕麦在青藏高原地区自然环境条件下有着独特的适应能力,并具有丰产、稳产的特征,在放牧牲畜冷季补饲中发挥着其它饲草饲料作物品种不可替代的作用,是解决冷季缺草、确保高寒草地畜牧业生产可持续发展的最佳品种。农业栽培技术措施的科学化、合理化应用对燕麦营养体农业生产蕴藏着巨大的潜力。  相似文献   
23.
吴渊  高颂  高雅灵  林慧龙 《草业学报》2018,27(10):171-182
新时期下,保障我国畜产食品供给安全是保障我国食物安全的重要内容之一,而“适度进口”是保障我国畜产食品供给安全的重要途径之一。如何才算“适度进口”,需对畜产食品进口的相关风险进行分析方可评判。运用进口依赖性评价模型对我国猪肉、鸡肉、羊肉、牛肉、鲜牛奶的进口依赖性风险进行分析发现,上述5种畜产食品均存在进口依赖性风险。其中,猪肉的风险来自美国、德国、丹麦、西班牙和加拿大;鸡肉的风险来自美国、巴西、阿根廷和波兰;羊肉的风险来自澳大利亚、新西兰和乌拉圭;牛肉的风险来自乌拉圭、澳大利亚、新西兰、阿根廷和加拿大;鲜牛奶的风险来自德国、法国、新西兰和澳大利亚。为降低我国畜产食品进口依赖性风险,短期内应采取畜产食品进口市场多元化策略以及用进口饲草料替代进口畜产食品的进口方式;长期应在保障“口粮安全”的前提下,调整农业结构,大力发展草地农业,减少对国际市场的依赖性。  相似文献   
24.
通过对振动筛理、垂直风选、旋风分离与沉降系统的研究,研制出集振动筛理、风选、旋风分离沉降、含尘气流循环再利用为一体的TFSQ型高效环保组合式粮食杂质清理筛。经应用测试和专家鉴定:该设备具有清理效率高、清理过程粉尘污染小,使用维护方便、可靠性强等优点,具有广阔的市场推广前景。  相似文献   
25.
城市农业公园的内涵、模式及路径   总被引:1,自引:0,他引:1  
城市农业公园是一种将城市元素与农业元素有机结合的融入城乡一体化发展理念的集生态、绿色、人文、产业等特征于一体的以农业为主题的城市公园。阐述了城市农业公园的内涵特征及其功能价值和城市农业公园的发展模式及其路径选择,并在此基础上,结合铜仁市的山水自然特征及其农业产业发展特色,从经验借鉴和实践研究层面对铜仁市城市农业公园的发展进行战略思考和总体设计。以铜仁市郊区的和平乡、坝黄镇、挞扒洞村以及松桃正大乡为例对以铜仁市城市农业公园建设为切入点打造铜仁生态旅游城市提出了具体的发展构想。  相似文献   
26.
梁锐 《中国食用菌》2021,(2):144-146,150
在"互联网+农业"融合发展背景下,食用菌企业需要借助互联网,构建市场主导、数字驱动的全新营销战略,助力产品营销。以"互联网+农业"模式为研究视角,分析食用菌产品营销现状,提出发挥技术优势、挖掘用户需求和建设优质平台等营销建议,以助力食用菌产品市场营销与效益转化。  相似文献   
27.
28.
结合生态农村园发展的要求及对同安造水村的综合考察,从多角度来分析市场形势和造水村的人文、地理等各条件的综合状况,为造水村观光农业旅游资源的合理开发提供较为科学的理论依据,同时,为同安区汀溪镇发展成为厦门市的后花园提供借鉴。  相似文献   
29.
Benefits of organic farming on soil fauna have been widely observed and this has led to consider organic farming as a potential approach to reduce the environmental impact of conventional agriculture. However, there is still little evidence from field conditions about direct benefits of organic agriculture on soil ecosystem functioning. Hence, the aims of this study were to compare the effect of organic farming versus conventional farming on litter decomposition and to study how this process is affected by soil meso- and macrofauna abundances. Systems studied were: (1) organic farming with conventional tillage (ORG), (2) conventional farming with conventional tillage (CT), (3) conventional farming under no-tillage (NT), and (4) natural grassland as control system (GR). Decomposition was determined under field conditions by measuring weight loss in litterbags. Soil meso- and macrofauna contribution on decomposition was evaluated both by different mesh sizes and by assessing their abundances in the soil. Litter decomposition was always significantly higher after 9 and 12 months in ORG than in CT and NT (from 2 to 5 times in average), regardless decomposer community composition and litter type. Besides, mesofauna, macrofauna and earthworm abundances were significantly higher in ORG than in NT and CT (from 1.6 to 3.8, 1.7 to 2.3 and 16 to 25 times in average, respectively for each group). These results are especially relevant firstly because the positive effect of ORG in a key soil process has been proved under field conditions, being the first direct evidence that organic farming enhances the decomposition process. And secondly because the extensive organic system analyzed here did not include several practices which have been recognized as particularly positive for soil biota (e.g. manure use, low tillage intensity and high crop diversity). So, this research suggests that even when those practices are not applied, the non-use of agrochemicals is enough to produce positive changes in soil fauna and so in decomposition dynamics. Therefore, the adoption of organic system in an extensive way can also be suggested to farmers in order to improve ecosystem functioning and consequently to achieve better soil conditions for crop production.  相似文献   
30.
Methane (CH4) is a potent greenhouse gas and the huge CH4 fluxes emitted from paddy fields can prejudice the eco-compatibility of rice cultivation. CH4 production in submerged rice crops is known to be highly influenced by water temperature. Hence, lowering ponding water temperature (LPWT) could be an option to mitigate CH4 emissions from paddy environments when it is possible either to irrigate with slightly colder water or to increase ponding water depth. However, paddy soil is a complex environment in which many processes are simultaneously influenced by temperature, leading to a difficult prediction of LPWT effects. For this reason, LPWT efficiency is here theoretically investigated with a one-dimensional process-based model that simulates the vertical and temporal dynamics of water temperature in soil and the fate of chemical compounds that influence CH4 emissions. The model is validated with literature measured data of CH4 emissions from a paddy field under time-variable temperature regime. Based on modeling results, LPWT appears promising since the simulated reduction of CH4 emissions reaches about −12% and −49% for an LPWT equal to −5 °C during the ripening stage only (last 30 days of growing season, when rice is less sensitive to temperature variations) and −2 °C over the whole growing season, respectively. LPWT affects CH4 emissions either directly (decreasing methanogenic activity), indirectly (decreasing activity of bacteria using alternative electron acceptors), or both. The encouraging results provide the theoretical ground for further laboratory and field studies aimed to investigate the LPWT feasibility in paddy environments.  相似文献   
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