小猪血液的多频电阻抗特性及其等效电路模型的研究  

Study on Multi-frequency Electronic Impedance Characteristics and Equivalent Circuit of Piglet Blood.

作　　者：张国鹏[1] 董秀珍[1] 尤富生[1] 李正[1] 林新[1] 郑万松[1] 

机构地区：[1]第四军医大学生物医学工程系医学电子工程教研室,陕西西安710032

出　　处：《航天医学与医学工程》2006年第1期51-55,共5页Space Medicine & Medical Engineering

基　　金：国家自然科学基金(30270378)

摘　　要：目的研究血液的电阻抗频率特性,构建血液的复电阻抗等效电路模型,为研究腹部慢性出血的无创监测提供一些基础数据。方法采用英国Solartron公司1260型频响分析仪,四电极测量法,进行了0Hz～20MHz频率内各个阶段的血液组织复电阻抗频率特性离体测量。结果估算出了特征频率fc的范围,根据实验数据重建了血液的复电阻抗电路模型并得到了串连电路模型的R_0,R_∞,P_(CPE),T_(CPE)特征参数值。β弛豫在测量频率1MHz左右开始明显,大于6MHz以后杂散电容效应开始显著。小猪的血液组织的电阻抗特性符合COLE模型的规律,特点是尼值比较大(＞1MHz)。初步分析了血液特征频率fc值比较高的原因。结论和其他腹部组织相比,小猪血液组织的多频特性特点明显：电阻率值明显小；容性效应在频率相对较高时才出现。对组织的高频测量要减小杂散电容对实验结果的影响。Objective Tostudy the frequency-characteristics of electronic impedance spectrum of blood and to reconstruct the equivalent circuit. To give some basic data for studies of noninvasive monitoring of chronic abdominal bleeding. Method Model 1 260 impedance/gain-phase analyzer of Solartron Company was used for the four electrodes measuring methods. Complex impedance of in vitro blood tissue in the whole frequency range from 0 Hz to 20 MHz was measured. Result The range of characteristic frequencyfc was estimated. According to the data of experiments, some equivalent circuit parameters R0 ,R∞ ,PCPE and TCPE were obtained for the serial circuit model. β relaxation was gradually obvious when the measuring frequency reached 1 MHz, and the effect of stray capacitance became obvious at about 6 MHz. The characteristic of piglet blood acts in accordance with the Cole Model generally and thefc of the blood tissue was relatively higher （ 〉 1 MHz）. The reason for the higher characteristic frequency fc of blood was also preliminarily explained. Conclusion In contrast with other abdominal tissues, the characteristics of piglet＇s blood is obvious for its lower resistivity value and higher frequency of capacitance response. When the working frequency is very high, measurements must be made to reduce the effects of stray capacitances.

关 键 词：多频电阻抗特性 血液 等效电路 电阻抗 频率特性 

分 类 号：R318[医药卫生—生物医学工程] R319[医药卫生—基础医学]