中文摘要：

研究人体肺癌组织与正常组织介电特性差异，建立人体肺部组织介电参数频率谱图，为基础医学和临床诊断提供理论依据和数据参考。以肺癌手术中切下的患者癌变组织和癌周正常组织为样本，控制测试舱的温度和湿度，采用Agilent公司的4294A阻抗分析仪，在100Hz一100MHz频率范围内测量样本组织的介电特性。基于Cole—Cole模型利用最小二乘曲线拟合方法，提取两种组织的特征参数。在所测频率范围内，肺癌组织的相对介电常数为正常组织的3～5倍，电导率为正常组织的1．6—3．3倍，肺癌组织的介电谱明显地向低阻抗方向移动。在提取的特征参数R0、R∞、a、T和fc中，低频电阻R0的差异具有统计学意义（P〈0．05）。人体肺癌组织与正常组织的相对介电常数、电导率及低频电阻R0存在明显差异，可为人体肺组织介电特性研究和EIT测量提供基础数据。

英文摘要：

This study is aim to investigate the differences of dielectric properties between lung cancer tissue and the normal tissue in vitro and establish the dielectric parameter frequency spectrum of human lung tissue which provide the basic theory and reference data for medical research and clinical diagnosis of lung cancer. Two main categories of tissues were considered as specimens： the central part of the tumor and the normal tissue around the tumor. After operation, specimens was put into test chamber in which the temperature and humidity were controlled at expected values. Then the measurement of specimens＇ dielectric properties was performed at frequency from 100 Hz to 100 MHz using 4294A impedance analyzer of Agilent Company. Finally the two categories of tissues＇ characteristic parameters were extracted by using the least square curve fitting method based on Cole-Cole model. The relative permittivity of lung cancer tissue was 3 - 5 times larger than that of the normal tissue. The conductivity of lung cancer tissue was 1.6 -3.3 times larger than that of the normal tissue. Impedance spectroscopy of lung cancer tissue moved apparently to low impedance direction. Among the characteristic parameters （ R0,R∞ ,a,Tandfc ） , the difference of low frequency resistance （ R0 ） between the two categories of tissues was statistically significant （ P 〈 0. 05 ）. The differences of dielectric properties and low frequency resistance between lung cancer tissue and the normal tissue are significant, which provide basic data for human lung tissue＇ s dielectric properties research and EIT measurement.