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诸葛健 《食品与生物技术学报》1985,4(3)
本文评论了有关细菌原生质体融合研究的进展,并报道了作者的部分研完工作。本文较充分讨论了原生质体融合的基本枝术步骤,包括出发株的选择,原生质体的制备,融合,再生,筛选和特性验证。介绍并推荐以育种为目的的该技术的较适使用条件。 相似文献
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Debarun Dutta Timothy Zhao Kai Bing Cheah Larke Holmlund Mark D.P. Willcox 《Contact lens & anterior eye》2017,40(3):175-183
Purpose
To determine the antimicrobial activity of the melimine derived peptide Mel4 against Delftia, Stenotrophomonas, Elizabethkingia, Burkholderia and to investigate biocompatibility of Mel4 as an antimicrobial coating on contact lenses in animals and humans.Methods
In vitro antimicrobial activity of Mel4 was determined against the four Gram negative bacteria by investigating growth curves for 24 h followed by viable counts to determine the minimum inhibitory concentration (MIC). Contact lenses were coated by covalently binding Mel4, characterized by amino acid analysis, and were investigated for changes in lens parameters. Safety of Mel-4 coated lenses were determined in a rabbit model of daily contralateral wear. A prospective, randomised, double-masked, contralateral, 1week daily wear human clinical trial was used to evaluate subjective responses and ocular physiology.Results
Mel4 was active against all the bacteria tested (MIC50 ranged from 31–1000 μg ml?1) and produced an antimicrobial surface on contact lenses. Mel4-coating resulted hydrophilic surface without any significant change in contact lens parameters, and showed no signs of cytotoxicity or ocular irritation during rabbit wear. During human clinical trial, there were no differences between Mel4 coated and uncoated contact lenses in lens performance indicators and ocular signs such as corneal fluorescein staining. Mel4 and control uncoated lenses had no differences in ocular symptoms during lens wear.Conclusion
Mel4 has achieved antimicrobial activity against variety of Gram negative bacteria that are often resistant to the action of cationic peptides and have been implicated in contact lens related adverse events. Mel4-coated contact lenses were safe to wear. 相似文献68.
探讨C 18.2 tex棉本色纱碳足迹各个阶段的计算方法。给出棉本色纱的产品流程分析图,确定系统边界,统计其活动水平数据及排放因子,然后根据PAS2050的碳足迹计算步骤计算其结果。结果表明:从原料生产到产品销售运输,整个过程的二氧化碳排放当量为4 738.78 kg(汽车),4 682.58 kg(铁运),其中,纱线生产阶段的排放当量最高,其次是棉花种植阶段,二者相加4 585.055 2 kg,占整体排放当量的96.73%(汽车)和97.94%(铁运)以上。指出:纺织工业减少棉纱碳排放的重点应在生产阶段。 相似文献
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《Fusion Engineering and Design》2014,89(7-8):1126-1130
Europe is currently developing two reference breeder blankets concepts for DEMO reactor specifications that will be tested in ITER under the form of Test Blanket Modules (TBMs): the Helium-Cooled Lithium-Lead (HCLL) concept which uses the eutectic Pb-16Li as both breeder and neutron multiplier; the Helium-Cooled Pebble-Bed (HCPB) concept which features lithiated ceramic pebbles as breeder and beryllium pebbles as neutron multiplier. Each TBM is associated with several sub-systems required for their operation; together they form the Test Blanket System (TBS). This paper presents the state of HCLL and HCPB TBS instrumentation design. The discussion is based on the systems functional analysis, from which three main categories of instrumentation are defined: those relevant to safety functions; those relevant to interlock functions; those designed for the control and scientific exploitation of the devices based on the TBM program objectives. 相似文献