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611.
黑素皮质素受体-1(MC1R)在鱼体中对黑色素细胞的分化及迁移起主要的调控作用,而且在神经系统和免疫系统中表现出不同功能。本研究对黄颡鱼表皮黑色素细胞的培养条件进行探索,并在此基础上对MC1R基因进行克隆,为后续研究黄颡鱼黑色素异常的细胞及分子机理研究提供基础。结果表明,黄颡鱼表皮黑色素细胞在27 ℃培养条件下,72 h开始贴壁生长,培养基中添加20 %小牛血清培养效果比添加10%小牛血清好。MC1R基因克隆方面,黄颡鱼MC1R基因全长为936 bp,编码312个氨基酸,与剑尾鱼(Xiphophorus maculates)、孔雀鱼(Poecilia reticulata)、条斑星鲽(Verasper moseri)、海鲈(Dicentrarchus labrax)、大菱鲆(Psetta maxima)等5种鱼类MC1R基因的同源性分别为97%、96%、90%、90%、90%,系统分析结果显示,黄颡鱼MC1R基因在进化树上的位置与黄颡鱼的分类所处位置基本吻合。证明黄颡鱼表皮黑色素细胞原代培养的条件为:27℃,添加20% 小牛血清,所克隆基因为黄颡鱼MC1R基因。 相似文献
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Microbial diversity in solar greenhouse soils in Round-Bohai Bay-Region,China: The influence of cultivation year and environmental condition 总被引:1,自引:0,他引:1
Tian Tian Chen Zhiqun Tian Yongqiang Gao Lihong 《Environmental science and pollution research international》2017,24(29):23236-23249
Environmental Science and Pollution Research - Round-Bohai Bay (RBB)-Region is an important crop production area in China, where vegetables are mainly produced in solar greenhouses. However,... 相似文献
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Wenguang Xiong Yongxue Sun Mengjia Zou Rizwan-Ul-Haq Muhammad 《Environmental science and pollution research international》2013,20(3):1746-1755
The full-length cDNA of catalase (EfCAT) from Eisenia fetida was cloned (GenBank accession no. JN617999). Sequence characterization revealed that EfCAT protein sequence contained proximal heme-ligand signature sequence (351RLFSYSDTH359), two glycosylation sites (N145 and N436), the proximal active site signature (61FDRERIPERVVHAKGAGA78), and 12 amino acids (N145, H191, F195, S198, R200, N210, Y212, K234, I299, W300, Q302, and Y355), which were identified as putative residues involved in NADPH binding. These conserved motifs and catalase signature sequences were essential for the structure and function of EfCAT. The present study also investigated the effect of the veterinary food additive zinc oxide on antioxidant processes in E. fetida, at different concentrations and exposure durations. A significant increase (by 106.0 % compared to controls) in CAT activity at 500 mg/kg was registered at day 15. The superoxide dismutase (SOD) activity at 500 mg/kg increased to the maximum value (by 44.0 %) measured at day 15. There was a significant increase in glutathione peroxidase (GPx) activity for all concentrations after 5 days. The results showed that dietary Zn (500 mg/kg) causes oxidative damage to earthworms. At early stages of earthworms exposed to ZnO, GPx is the main enzyme to impair the oxidative status; while at later stages the enzymes CAT and SOD were the main indicators of oxidative stress. The antioxidant enzymatic variations may be an adaptive response of earthworms to survive in contaminated soils. 相似文献
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This article considers the target level of safety (TLS) for Chinese airspace. If collision risk is lower than TLS, we can say the separation minima meet the safety requirements, so the TLS is the safety limit on the flight operation. But there are no regulations on TLS in China by now, hence, it is necessary to judge whether it is fair to apply the TLS proposed by ICAO to evaluating air traffic safety in China.The accidents data of more than 50 years are collected, and we apply the trend extrapolation to predicting the safety level in the future so as to resolve the TLS problem. The resulted showed the safety level in the period from 2010 to 2020 is very close to TLS established by ICAO. The results show the safety level of collision risk in China has reached the international level and it is rational to use TLS of ICAO to assess collision risk. 相似文献