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7月3日至4日广东省科协在广州召开第七次代表大会,出席这次大会的正式代表680名,特邀代表50名,特邀嘉宾50名。会议由协会主席卢钟鹤主持。会议的主要议程:一是听取和审议广东省科协第六届委员会的工作报告;二是表彰先 相似文献
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Wang MF Lian HZ Mao L Zhou JP Gong HJ Qian BY Fang Y Li J 《Journal of agricultural and food chemistry》2007,55(14):5552-5558
A capillary gas chromatographic (GC) method has been developed for the separation and determination of policosanol components extracted from rice bran wax. A Varian CP-sil 8 CB column was employed, and an oven temperature was programmed. Gas chromatography-mass spectrometry (GC-MS) was used to identify the composition of policosanol. Quantitative analysis was carried out by means of hydrogen flame ionization detector (FID) with dinonyl phthalate (DNP) as internal standard. The results indicated that the extract obtained by dry saponification has the highest contents of octacosanol and triacontanol among extracts by all used extraction methods including dry saponification, saponification in alcohol, saponification in water (neutralized and non-neutralized), and transesterification. Meanwhile, the GC-MS fingerprint of policosanol extracted by dry saponification has been established. Euclidean distance similarity calculation showed remarkable consistency of compositions and contents among 12 batches of policosanol from a rice bran wax variety. This protocol provided a rapid and feasible method for quality control of policosanol products. 相似文献
85.
Xiangbing Mao Mei Lv Bing Yu Jun He Ping Zheng Jie Yu Quyuan Wang Daiwen Chen 《畜牧与生物技术杂志(英文版)》2014,5(1)
Oxidative stress can induce abnormal tryptophan metabolism. The present study was mainly conducted to determine the effect of dietary tryptophan levels on oxidative stress in the liver of weaned pigs challenged by diquat. A total of 36 PIC piglets weaned at 21 days of age were randomly allotted to 1 of 3 diets containing dietary tryptophan levels of 0.18, 0.30, and 0.45% for 14 d. On day 8, the piglets were injected intraperitoneally with sterile 0.9% NaCl solution or diquat (10 mg/kg body weight). During the first 7 d of trial, increasing dietary tryptophan levels enhanced average daily gain (P = 0.09) and average daily feed intake (P = 0.08), and decreased the feed efficiency (P < 0.05) of piglets. The growth performance was decreased by diquat injection (P < 0.05). Diquat injection also decreased the activities of the superoxide dismutase (SOD) and glutathione peroxidase (GPx) in the plasma and liver (P < 0.05), increased plasma malondialdehyde (MDA) (P < 0.05) and urea nitrogen (P < 0.05) concentrations, and enhanced MDA concentration (P = 0.09) and tryptophan 2,3-dioxygenase (TDO) activity (P = 0.07) in liver of piglets. Increasing dietary tryptophan levels could attenuate the effects of diquat injection on the MDA (P = 0.06) concentration and the activities of SOD (P = 0.09) and GPx (P = 0.05) of the liver, and plasma urea nitrogen (P = 0.06) concentration in the piglet. There was a synergistic role for increasing TDO activity in the liver between dietary tryptophan levels and diquat injection (P < 0.05). These results suggest that increasing dietary tryptophan levels could attenuate the oxidative stress of the liver in weaned piglets intraperitoneally injected with diquat via enhancing the antioxidant capacity. 相似文献
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Ma Chong Tu Qiang Zheng Shengmeng Deng Shaohong Xia Yinhang Mao Wanqiong Gao Wei Hu Lening Kuzyakov Yakov Hu Yajun Su Yirong Chen Xiangbi 《Journal of Soils and Sediments》2022,22(10):2604-2607
Journal of Soils and Sediments - Soil acidification is a major issue in agricultural ecosystems. However, how agricultural land uses shape the soil pH pattern and affect soil acidification on a... 相似文献
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在室内条件下采用浸渍法,分别测定了12种杀虫剂对南瓜实蝇蛹的毒力和二元混剂的共毒系数。供试杀虫剂对南瓜实蝇蛹的毒性大小依次为:毒死蜱>喹硫磷>氯唑磷>甲基异硫磷>辛硫磷>敌敌畏。高效氯氟氰菊酯、阿维菌素、敌百虫、丁硫克百威、噻虫嗪、高效氯氰菊酯对南瓜实蝇蛹的药效较差。敌百虫和辛硫磷(1:9)对南瓜实蝇蛹的LC50为96.2879mg/L,辛硫磷和毒死蜱(9:1)的共毒系数为590.77。 相似文献
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浅谈重大动物疫病损失补偿制度 总被引:2,自引:0,他引:2
重大动物疫病损失补偿是指政府利用公共资源(包括政府行政资源和其他社会资源)对在防控、扑灭重大动物疫病过程中受损的畜禽养殖、加工、流通等企业、个体业主及相关环节实施补偿的行为。我国畜牧业总体规模较大,畜禽养殖种类多,饲养条件复杂,集约化养殖程度低,抗风险能力弱,一旦发生和流行重大动物疫病,极易形成重大损失,对畜牧业生产造成巨大破坏,影响社会和谐稳定。因此,实行重大动 相似文献