【摘要】 探讨用多变量统计分析方法对激光诱导的SD大鼠结肠组织5-ALA-PpⅨ荧光光谱进行分类,以诊 断结肠早癌。对20只DMH诱导的SD大鼠,12只诱导鼠的第二代鼠,8只正常SD大鼠,按25 mg·kg-1体 重剂量尾静脉注射5-ALA,150 min后进行活体激光检测,钛宝石激光器激发波长370 nm。将343条3类组 织谱线分为训练组和预测组,经预处理,再采用主成分分析法提取4个主成分变量。利用训练组建立逐步多 变量Logistic回归模型,并对预测组预测。3类组织病理类型两两结合,共构建3个回归方程。正常组织与早 癌及进展期癌识别的特异性分别为100％,98．4％,敏感性分别为96％,100％,准确率分别为98％, 99．2％。在光敏剂5-ALA的辅助作用下,对370 nm激光诱导的结肠组织荧光光谱,采用主成分变量压缩与 逐步多变量Logistic回归分析方法相结合,可以获得较高的正常组织对早癌及进展期癌组织识别特异性和敏 感性,是一种较有潜力的结肠早癌无损诊断方法。更多还原

【Abstract】 In order to diagnosis colon early cancer with laser-induced 5-ALA-PpⅨ fluorescence spectra, a multivariate statistical method to distinguish these fluorescence spectra acquired in vivo was developed. 343 spectra were collected from 8 normal SD rats, and 20 1,2-DMH-induced SD colon cancer models, and 12 second generation rats of induced rats. 150 min after trail intravenous injections of 5-ALA at a dose of 25 mg·kg-1 BW, fluorescence spectra excited with 370 nm Ti-laser were collected in vivo. All spectra were divided into a calibration group and a prediction group. After preprocessing, 4 principal components were extracted with PCA. And then, discrimination models were built by stepwise multivariate logistic regression (SMLR) on calibration group. 3 pathological styles were combined each other, and then 3 SMLR models were derived. Normal tissues were classified from early cancers and advanced cancers with sensitivity of 100% and 98.4% , and specificity of 96% and 100% , and accuracy of 98% and 99.2% on prediction group, respectively. The multivariate statistical discrimination method of PCA and SMLR together can effectively distinguish normal tissues from early cancers and advanced cancers with high sensitivity and specificity by means of systemic 5-ALA at low dose. laser induced fluorescence 5-ALA-based technique is promising for the detection of colonic early cancer.更多还原