【摘要】 目的　从亚慢性染铅大鼠中枢神经系统电活动的变化 ,寻找铅中毒早期诊断敏感指标。方法　利用脑电信号及功率谱的混沌时间序列分析方法进行研究。结果　从染铅大鼠额、顶、枕部获取的脑电信号进行功率谱分析 ,在染铅组与对照组、各染铅组之间均未发现明显差异。脑电信号的混沌时间序列分析所得的分形维数及第一Lyapunov指数的值均表明脑电波具有混沌现象的典型特征。正常大鼠在额部、顶部和枕部脑电分形维数为 3.74± 0 .0 9、2 .2 3± 0 .31、4.2 8± 0 .43;低剂量组染铅大鼠的对应值分别是 7.77± 0 .34、7.78± 0 .6 4、7.6 5± 0 .95 ,两者间分形维数的差异有显著性 (P <0 .0 1)。各剂量组和对照组第一Lyapunov指数均为正值。 结论　铅接触大鼠脑电信号具有混沌特性 ,利用混沌时间序列分析为早期诊断提供灵敏的检测指标是可能的。更多还原

【Abstract】 Objective To find a sensitive method for early diagnosis of plumbism according to the change of electroactivity in rat central nervous system after subchronic exposure to low level lead. Methods The chaotic time series analysis(CTSA) of electroencephalogram(EEG) signal and EEG power spectra was used in the study.Results No significant difference was found between control and exposed groups or among exposed groups in EEG power spectra.Correlation dimension and first Lyapunov exponent of CTSA showed that EEG had typical characteristics of chaos.The correlation dimension of EEG in frontal,cupular and occipital part were 3.74±0.09,2.23±0.31 and 4.28±0.43 respectively for normal rats and 7.77± 0.34,7.78±0.64 and 7.65±0.95 for low dosage lead administrated rats.There was marked difference between the two groups.The first Lyapunov exponents of control and exposed groups were all positive values. Conclusion EEG of lead exposed rats shows chaotic characterization.CTSA could be used to provide sensitive index for early diagnosis of lead exposure.更多还原