Objective: On account of elevated fetal radiosensitivity, estimates of internal and external dosimetry are very important for a pregnant woman and her fetus. By establishing Chinese reference of physiological characteristics based on China's pregnant women reference series model, this paper researches the internal dosimetry of pregnant women. Methods:Based on Chinese reference mathematical phantom-"NHMAN 1.0", we build a radiation stylized pregnant phantom withChinese physiological feature. Using MIRD scheme and montecarlo method do some research of internal dosimetry about pregnant woman. Results: SAF values to self and to fetus by several source organs were calculated individually. Kidney and lung as example were compared with previous data derived from ORNL phantoms. The S values of three radionuclides in kidney and lung were also calculated. Conclusions: SAF values to self by kidney and lung agree well with ORNL data, but to fetus are different between them, that maybe mainly because of the different phantom and different method.%目的:由于胎儿具有较高辐射敏感性,对其进行内照射剂量学评估具有十分重要的意义.本研究通过建立基于中国人参考生理特征的中国孕妇参考人系列模型,对其进行内照射剂量学的研究,为孕妇等特殊人群内照射辐射防护工作提供技术及理论基础.方法:在MIRD模型的基础上根据中国参考人生理特征建立了中国参考人数学模型——“NHMAN 1.0”,然后在此模型基础上依据孕妇生理参考数据进行改进,建立中国孕妇参考人模型.借助蒙特卡罗方法使用MIRD内照射计算模式对其进行内照射剂量学的研究.结果:采用Monte Carlo方法模拟了10 keV～4 MeV范围内9种不同能量的光子在人体组织器官内的输运过程,得出了各源器官不同能量的光子对胎儿及源器官自身的比吸收分数,以肾脏和肺为源器官为例,将结果与美国橡树岭模型(ORNL)的推荐值进行了比较；计算结果表明,计算发现靶器官对自身的SAF因子与ORNL孕妇模型总体相对差异较小基本吻合,而靶器官对胎儿的SAF因子与其差异相对较大.同时还计算了Ir192、Cs137、Co60在肾脏和肺部时,源器官对胎儿的S因子.结论:验证了该方法的可行性.基于中国参考人建立的孕妇模型与ORNL模型解剖结构有一定的差异,并在内照射SAF等辐射防护量上也有相应的差别,建议在国内进行辐射防护工作时使用基于中国参考人数据.
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