中文摘要：

通过测量分化型甲状腺癌患者在全甲状腺切除术后，接受131I治疗后对周围环境的辐射剂量率，采用单指数曲线拟合方法处理测量数据，计算出分化型甲状腺癌患者的131I平均有效半衰期为（14.6±6.5）h，该结果与国外文献报道均值接近，说明131I有效半衰期不存在人种差异性。对患者有效半衰期进行的统计学检验表明，患者有效半衰期与服药次数和年龄有负相关关系，与患者性别和服药量没有显著关系。

英文摘要：

The effective half-life Teff of 131I in patients with differentiated thyroid cancer was determined by monitoring the radiation dose rate around the patients at different time after radioiodine-131 therapy. The average Teff of 131I for the 21 patients post thyroid surgery was estimated to be （14.6±6.5） h. The value is similar to those reported by other authors. It indicates that no difference of 131I Teff exists among different races. The results of statistical analysis show that negative correction exists between the Teff and the age of patient, the number of times of radioiodine therapy. On the other hand, no significant difference is observed between the Teff and the gender, the administered activity.