六十年代以来,通过对辐射细胞遗传学的深入研究,发现人体淋巴细胞染色体对电离辐射有高度的敏感性,因而通过对染色体畸变的观察不仅能早期发现辐射损伤,而且能对受照射个体进行吸收剂量的估算,作为“生物剂量计”的染色体畸变分析,已日益受到人们的重视,目前,国内外均在深入研究和广泛应用。然而,用这种“生物剂量计”估算剂量时,所分析的染色体宜选择第一次分裂周期的细胞。过去由于无法区分各期细胞,一般采用52～54小时的培养时间,认为这时大部分细胞是处于第一次分裂周期。近年来,随着染色单体分染法(Sister Chromatid Differe-ntiation)的应用,发现影响人体外周血淋巴细胞分裂周期的因素很多,Purrott、Crossen和Jacob等认为,培养液的成分、电离辐射、Brdu的浓度,以及不同个体等因素,都可以影响细胞分裂周期。本文用荧光一 Since the 1960s, through in-depth study of radiation cytogenetics, it has been found that human lymphocyte chromosomes are highly sensitive to ionizing radiation. Therefore, not only early detection of radiation damage, but also exposure to irradiated individuals can be performed by observing chromosome aberrations. The estimation of the absorbed dose, as a “biological dosimeter” chromosome aberration analysis, has increasingly attracted people’s attention. At present, both at home and abroad are deeply studied and widely used. However, when estimating the dose with this “biological dosimeter”, the analyzed chromosome should select the cells of the first division cycle. In the past, due to the inability to distinguish cells in each phase, a culture time of 52 to 54 hours was generally used, and it is believed that most cells are in the first division cycle at this time. In recent years, with the application of Sister Chromatid Differe-ntiation, it has been found that there are many factors affecting the peripheral blood lymphocyte division cycle in humans. Purrott, Crossen, and Jacob believe that the components of the culture fluid, ionizing radiation, The concentration of Brdu, as well as various individual factors, can affect the cell division cycle. This article uses fluorescence