The kinetics on the growth of T.ferrooxidans in the presence of Cu(Ⅱ) was studied using of series piezoelectric quartz crystal (SPQC). Arsenic ion inhibits the growth of T.ferrooxidans , which is consistent with the ...The kinetics on the growth of T.ferrooxidans in the presence of Cu(Ⅱ) was studied using of series piezoelectric quartz crystal (SPQC). Arsenic ion inhibits the growth of T.ferrooxidans , which is consistent with the previous results by other measuring methods. This further demonstrates that the SPQC can monitor the chemical activity of T.ferrooxidans growth. Cupric ion accelerates the growth of T.ferrooxidans . The mechanism was discussed, i. e., copper promotes the protein enzyme of T.ferrooxidans , rusticyanin, to form over the range of cupric ion concentration studied. The reaction order of cupric ion in accelerating the bacterial growth is 0.067. The growth of T.ferrooxidans is dependent on temperature, the apparent reaction activation energy decreases from 25.56 kJ/mol to 18.32 kJ/mol because of the addition of 10 mg/L Cu(Ⅱ) to the bacterial growth solution of pH 2.0 at initial inoculum of 10%.展开更多
文摘The kinetics on the growth of T.ferrooxidans in the presence of Cu(Ⅱ) was studied using of series piezoelectric quartz crystal (SPQC). Arsenic ion inhibits the growth of T.ferrooxidans , which is consistent with the previous results by other measuring methods. This further demonstrates that the SPQC can monitor the chemical activity of T.ferrooxidans growth. Cupric ion accelerates the growth of T.ferrooxidans . The mechanism was discussed, i. e., copper promotes the protein enzyme of T.ferrooxidans , rusticyanin, to form over the range of cupric ion concentration studied. The reaction order of cupric ion in accelerating the bacterial growth is 0.067. The growth of T.ferrooxidans is dependent on temperature, the apparent reaction activation energy decreases from 25.56 kJ/mol to 18.32 kJ/mol because of the addition of 10 mg/L Cu(Ⅱ) to the bacterial growth solution of pH 2.0 at initial inoculum of 10%.
文摘目的探讨增强T2^(*)加权血管成像(enhanced T2 star-weighted angiography,ESWAN)序列中R2^(*)值、相位值、幅度值在T2WI低信号肾脏病变良恶性鉴别诊断中的可行性。材料与方法回顾性收集行ESWAN检查、经病理组织学证实的145例T2WI低信号肾脏病变患者(共145个病灶,恶性病变112个,良性病变33个)的术前MRI图像。在肿瘤最大面积的层面上绘制肿瘤T2WI低信号的感兴趣区。通过Kruskal-Wallis检验、卡方检验对参数进行比较,将有统计学意义的参数进行联合,通过多变量logistic回归建立模型,分析差异有统计学意义的参数,并且绘制其鉴别T2WI低信号肾脏病变良恶性的受试者工作特征(receiver operating characteristic,ROC)曲线,采用DeLong检验评价其诊断效能。结果R2^(*)值和幅度值鉴别T2WI低信号肾脏病变良恶性差异具有统计学意义(P=0.001)。R2^(*)值的ROC曲线下面积(area under the curve,AUC)为0.891[95%置信区间(confidence interval,CI):0.829~0.937,P<0.001],敏感度、特异度分别为97.3%、72.7%;幅度值的AUC为0.869(95%CI:0.803~0.920,P<0.001),敏感度、特异度分别为86.6%、81.8%;相位值的AUC为0.563(95%CI:0.478~0.645,P=0.249),敏感度、特异度分别为67.9%、54.6%;R2^(*)值联合幅度值的AUC为0.886(95%CI:0.823~0.933,P<0.001),敏感度、特异度分别为97.3%、72.7%;R2^(*)值联合病变长径的AUC为0.894(95%CI:0.832~0.939,P<0.001),敏感度、特异度分别为92.0%、81.8%;幅度值联合病变长径的AUC为0.858(95%CI:0.790~0.910,P<0.001),敏感度、特异度分别为75.9%、90.9%。结论R2^(*)值、R2^(*)值联合病变长径、R2^(*)值联合幅度值是鉴别T2WI低信号肾脏病变良恶性的有效方法,R2^(*)值联合病变长径具有更好的诊断性能。