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对12C6+ 离子辐照诱变高产阿维链霉菌株ZJAV-Y1-203 和原始菌株ZJAV-A-1 的摇瓶发酵pH 值、菌体浓度、碳源和氮源代谢进行了测定,研究了12C6+ 辐照对阿维链霉菌的代谢效应。在发酵前期(48h),原始菌株发酵液pH 值低于突变菌株;在发酵96~196 h,诱变高产菌株ZJAV-Y1-203 繁殖快,生长旺盛,N的利用率高;菌体浓度大于原始菌株的浓度,且发酵液的pH 稳定,菌体处于代谢相对更稳定期;在发酵144~240 h,诱变高产菌株ZJAV-Y1-203 对糖源消耗低于原始菌株ZJAV-A-1。这些结果表明,12C6+ 离子辐照对阿维链霉菌代谢影响有利于阿维菌素合成。pH value, mycelium concentration, carbon source and nitrogen metabolism in flask fermentation of the mutant high-producing strain ZJAV-Y1-203 and the original strain ZJAV-A1 have been investigated, in order to show the metabolic effect of avermitilis irradiated by ion beam of 12C6. In early stage (48 h) of the fermentation, pH value of the original fermentation was lower than that of the mutant strains. In 96~196 h of fermentation, the nitrogen utilization in the strains ZJAV-Y1-203 was higher than that in the original strains, its reproductive was fast, and its growing was vigorous. The mycelium concentration of ZJAV-Y1-203 was greater than the original strain, and the pH value of fermentation were stable, so its metabolism was relatively more stable. In 144240 h of fermentation, the strain ZJAV-Y1-203 on sugar consumption was less than the original strains. The effect of 12C6 ion irradiation on metabolism of Streptomyces avermitilis is conducive to the synthesis of avermectin. 相似文献
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选用12C6+ 离子束对阿维链霉菌诱变选育高产菌株与原始菌株进行辐照诱变, 研究其累进辐照效应。实验结果表明,在辐照剂量为10 Gy时, 原始菌株比诱变高产菌株存活率高, 抗辐射能力强;辐照剂量高于30 Gy时,诱变高产菌株比原始菌株存活率高, 抗辐射能力强。原始菌株正突变率最高的辐照剂量为50 Gy, 致死率99.43%,正突变率最高, 达34.2%;对诱变高产菌株辐照剂量为30 Gy,致死率94.97%,正突变率最高, 达23.5% 。累进辐照效应降低了最佳辐照剂量。 Mutagenic effect on the mutant high producing strain ZJAV Y1 203 and the original strain ZJAV A1 irradiated by ion beam of 12C6+ have been investigated. The experimental results indicated that the original strain has higher survival rate and stronger resistance to radiation than mutant high producing Strain at dose of 10 Gy. The mutant high producing strain has higher survival rate and stronger resistance to radiation than the original strain at the dose higher than 30 Gy. The lethality was 97% and the highest rate of orthomutation was 34.2%, when ZJAV A1 was irradiated by 50 Gy 12C6+ beam. The lethality was 94.97% and the highest rate of orthomutation was 23.5% when ZJAV Y1 203 was irradiated by 30 Gy 12C6+ beam. The best radiation dose is decreased by progressivity irradiation. 相似文献
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基于Logistic回归建模和马尔可夫链蒙特卡罗方法计算后验描述丁酸梭菌株对于给定辐照剂量区的应答趋势 总被引:1,自引:0,他引:1
利用马尔可夫链蒙特卡罗(Markov Chain Monte Carlo,MCMC)方法估计Logistic回归模型中的参数,就是要构造一个以参数的后验分布为其平稳分布的非周期不可约的马尔可夫链,然后用该平稳分布中抽出的样本点计算蒙特卡罗积分。上述理论方法可以解决实验样本数据由于存在定和约束和多重共线性、在进行经典的logistic回归建模时的困难问题。基于此方法,研究了丁酸梭菌株对于给定辐照区间剂量的应答趋势,用模型挖掘数据所隐含的内在信息并导出了Logistic回归模型参数的贝叶斯框架下的50%,90%,95%和99%的置信区间。结果表明,运用Logistic与马尔可夫链耦合模型在有关给定辐射剂量对于微生物作用效果问题的logistic回归建模中具有较大的科学性与很好的使用性,从而可以为辐照诱变处理微生物制定辐照剂量区提供理论支持和回归技术借鉴。Using the Markov Chain Monte-Carlo method to estimate the parameters in the Logistic regression model, we constructed a non-periodic irreducible Markov Chain with the posterior distribution of the parameters as stationary distribution, and then used the sample points extracted from the stationary distribution to calculate the Monte-Carlo integral. The above theoretical method can solve the difficult problem of classical logistic regression modeling because of the existence and limitation of the experimental sample data and the multicollinearity. In the classical regression setup with a continuous response, the predicted values can range over all real numbers. Therefore, a different modelling technique is needed. In this work, the results describe in detail a previously unknown lethality trend following 12C6+ heavy-ion irradiation of Clostridium tyrobutyricum. By Markov Chain Monte-Carlo can calculate the model fit for a randomly selected subset of the chain and calculate the predictive envelope of the model. The grey areas in the plot correspond to 50%, 90%, 95%, and 99% posterior regions. More importantly, although this study focused on the use of the method in heavy-ion irradiation of microbial, its results are broadly applicable. 相似文献
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The title compound 6?-chloro-4?-methylene-3 H-spiro [isoben zofura-1,3?-isochroman], C_(17)H_(13)ClO_2, was prepared and characterized by IR, NMR, HRMS and single-crystal X-ray diffraction. This compound has a bisbenzannulated [5,5]-spiroketals skeleton. It crystallizes in orthorhombic, space group P212121 with a = 13.383(3), b = 7.6120(17), c = 13.793(3) ?, Z = 4, Dc= 1.275 g/cm~3, μ = 0.28 mm~(–1), F(000) = 592, wR = 0.1443 and R = 0.0557. The preliminary biological test showed that the title compound has good anti-bacterial activities in vitro. 相似文献
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综述了稳定同位素在药物动力学研究中的最新发展,随着质谱和色-质联用等仪器的普及,它将成为药物研究中的一种重要手段. The recent progress of the Stable Isotopes(SI) research on pharmacokinetics is reviewed. With development of MS and GC MS, it will be an important method for studying drugs. 相似文献
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利用兰州重离子研究装置(HIRFL) 提供的12C6+ 离子束辐照菘蓝干种子(辐照剂量为10,35,60,90 和140 Gy,剂量率20 Gy/min),探讨了重离子束辐照对菘蓝M1代的生物学效应。研究发现,不同剂量的12C6+ 离子束辐照后,菘蓝种子的发芽率、成苗率、株高、根长和根冠比等生物学性状以及对菘蓝中靛玉红和4(3H) 喹唑酮含量均发生了变化,其中株高和根长随辐照剂量的增加而降低;菘蓝叶和根中的4(3H) 喹唑酮和靛玉红的含量随辐照剂量增加呈马鞍形增加关系。这表明:12C6+ 重离子束辐照菘蓝种子具有明显的当代损伤效应, 并可显著提高菘蓝中靛玉红和4(3H) 喹唑酮的含量,其辐照适宜诱变剂量为35 Gy。To investigate the M1 biological effects of heavy ions on Isatis indigotica Fort, its dry seeds were irradiated by 12C6+ beam with the dose of 0, 10, 35, 60, 90 and 140 Gy respectively,at the rate of 20 Gy/min delivered by the Heavy Ion Research Facility in Lanzhou (HIRFL). The results showed that biological characters such as germinating rate, germinating potential, survival rate, plant height, root height and root-shoot ratio were changed after irradiation. Moreover, the plant height and root height decreased in a dos dependent manner. The indirubin and 4(3H) quinazolinone content of Isatis indigotica Fort was improved and exhibited obviously “saddle” trends with irradiation dose increasing.Data suggest that exposure with low-dose 12C6+ to seeds of Isatis indigotica Fort has obvious injury effects at the first generation, and the active ingredient content of Isatis indigotica Fort may be improved by carbon ion beamirradiation. It is concluded that the suitable irradiation dose of mutation breeding is 35 Gy for the seeds of Isatis indigotica Fort. 相似文献
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对经中能的18O8+离子辐照过的胸腺嘧啶N2O饱和水溶液进行了研究,利用气相色谱(GC)、气相色谱 质谱联用(GC MS)、气相色谱 红外光谱联用(GC FTIR)等仪器对辐照后的产物进行了分析、鉴别,观察到了5,6 二氢胸腺嘧啶、5 羟基 5 甲基 乙内酰脲、5 羟基(氢) 6 (氢)羟基胸腺嘧啶、5 羟甲基尿嘧啶、顺(反)胸腺嘧啶二醇和二聚体等产物。虽然重离子主要是通过辐照水溶液中产生的羟基、氢原子等对胸腺嘧啶分子产生了作用,但与γ射线作用机制和结果是不同的。 相似文献
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