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71.
广东汕尾1年3茬池塘凡纳滨对虾健康养殖技术 总被引:2,自引:0,他引:2
引入养殖工程理念,集成虾池设计、立体增氧系统、有益微生物调控养殖生态环境、营养免疫增强剂提高对虾免疫力、养殖废水无害化生态处理、HACCP管理理念等诸技术,形成1年3茬池塘对虾健康养殖技术,对虾养殖年产量可达6.4 kg/m2,与传统高位池方法相比,产量可提高30%,单价提高30%,年经济效益提高70%,从而有效提高了养殖者的生产效益。 相似文献
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The survival rates of shrimp larvae in different stage are higher than those of control groups when probiotic bacteria strains X4B-1 and X1B-1 which are isolated from gut of adult shrimp are added into the little volume rearing sea water of shrimp larvae. The effects of probiotic bacteria are evaluated by challenge test (pathogenic bacteria Z3G2 isolated from disease shrimp larvae in the hatchery of Jimo town) and low salinity stress resistance tests on shrimp larvae, the survival rate and lengths of the shrimp larvae in the experiment are determined. Results indicate that 1. The survival rate, ability of resistant to low salinity, lengths of the delivered shrimp larvae are improved after the strains of probiotic bacteria, X4B-1 or X1B-1, are added into the rearing sea water of hatchery. 2. The addition of the probiotic bacteria could not influence the change of the bacteria number, NH3-N and COD value in the rearing sea water. 3. The probiotic bacteria used in the experiment have many enzymes such as Lipase, Amylase, Gelatinase and Lecithinase. These enzymes may help the probiotic bacteria to digest the food components fed to shrimp larvae and increase the digestive efficiency of post larvae. This may be one of the reasons why these probiotic bacteria are beneficial to the shrimp larvae. 相似文献
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黄峻松 《科技导报(北京)》2018,36(4):62-68
美军在海上战争理论研究领域处于世界前沿。为预研海上战争的发展,充实发展中国海上战争理论,按照"分布式杀伤的理论来源与实践基础-与未来智能化海上战争的关系-是否符合海上战争的客观规律"的思路,考察了分布式杀伤在海上战争演进中的历史必然性,表明分布式杀伤是海上战争形态的发展趋势,分析了分布式杀伤对作战能力建设的要求。 相似文献
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Verenice Merlín-Lucas Rosa María Ordoez-Razo Fernando Calzada Aida Solís Normand García-Hernndez Elizabeth Barbosa Miguel Valds 《Molecules (Basel, Switzerland)》2021,26(24)
Annona muricata (Am) is a plant used in traditional Mexican medicine to treat cancer. In this study, ethanol extracts of Am collected in Acapulco and Tecpan from Guerrero state were evaluated orally on Balb/c mice inoculated with 4T1 cells, for cytotoxic activity (CA) on 4T1 cells, in brine shrimp lethality assay (BSLA), and for acute oral toxicity in mice. In addition, ethanol extracts were subjected to high-performance liquid chromatography (HPLC) with diode array detection. Results showed that the extracts collected in December in Acapulco (AcDe) and Tecpan (TeDe) exhibited the most significant antitumor and cytotoxic activity. In the BSLA, the most important effect was observed in the extracts from Acapulco and Tecpan collected in June (AcJu) and August (TeAg), respectively. The samples from Acapulco (AcJu, and AcAg) and Tecpan (TeJu and TeAg) showed the highest toxicity. The analysis of the extracts, AcDe and TeDe, by HPLC revealed that flavonoids, rutin, narcissin, and nicotinflorin were the major components. These findings suggest that extracts from Am collected in Acapulco and Tecpan in the month of December may be an important source to obtain flavonoid glycosides with anticancer potential specifically against breast cancer. This also supports the use of Am to treat cancer in Mexican traditional medicine. 相似文献
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四乙氧基硅在HCl催化下水解形成硅溶胶。将硅溶胶与河虾抗体混合均匀后,涂于玻碳电极表面制备得非标记型河虾抗体免疫传感器。采用Fe(CN)63-/4-的磷酸盐缓冲溶液(pH 6.5)为测试底液,研究此传感器在免疫反应中的循环伏安和交流阻抗特性。结果显示免疫反应后传感器的循环伏安图上未出现新的氧化-还原峰,表明该免疫反应属于非氧化还原过程。采用交流阻抗监测电极表面,发现传感器阻抗值随虾过敏原浓度的增加而增大。对交流阻抗图进行分析,结果表明电极表面的免疫反应是一个受电子转移控制的过程。当虾过敏原浓度在0~10 ng/mL之间,电极表面电子转移阻抗的增加值与虾过敏原浓度呈线性关系,检出限为0.1 ng/mL(S/N=3)。该方法已成功应用于河虾制品中过敏原的测定。 相似文献
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砷污染物是水体环境中重点优先监测的污染物之一。归纳总结了近年来高矿化度水体系中痕量砷的测定方法研究进展,内容包括样品的处理(稀释、预富集和基体分离)分析,指出了高矿化度水体系中不同形态砷分析的发展方向。 相似文献
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