报道了乳铁蛋白（ＬＦ）的提纯方法，放射免疫分析法的建立及其在肺癌诊断中的应用。用改良的萃取法获得相对分子量为７５０００Ｄ的ＬＦ，其聚丙烯酰胺凝胶电泳及免疫双扩散结果均呈单一色带，１ｍＬ人乳可提取０．５４２ｍｇＬＦ。放射免疫分析批间及批内变异分别为４．７７％和１３．５９％，回收率９７．９９％。对３６例肺癌、２１例肺部感染和４例正常人的支气管冲洗液中乳铁蛋白（ＢＬＦ）进行测定，结果表明肺癌组明显高于肺部感染组和正常对照组，其中肺腺癌的检出率最高。病理分期表明，ＢＬＦ与肺癌的早、晚期呈负相关 Reported the purification of lactoferrin (LF), the establishment of radioimmunoassay and its application in the diagnosis of lung cancer. LF with a relative molecular weight of 75000D was obtained by a modified extraction method. The results of polyacrylamide gel electrophoresis and double immunodiffusion showed a single band, and 0.542mgLF was extracted from 1mL human milk. Inter-assay and intra-assay variations of radioimmunoassay were 4.77% and 13.59%, respectively, with a recovery of 97.99%. The determination of lactoferrin (BLF) in bronchoalveolar lavage fluid of 36 cases of lung cancer, 21 cases of lung infection and 4 cases of normal controls showed that the lung cancer group was significantly higher than the lung infection group and the normal control group, and the lung adenocarcinoma The highest detection rate. Pathological staging showed that BLF was negatively correlated with early and late stages of lung cancer