中文摘要：

目的对比观察17a α—D-高炔雌二醇-3-乙酯（DHEA）对不同品系小鼠肺腺癌的抑瘤作用及探讨合用^137Cs γ射线照射是否具有抑瘤增效作用。方法将LA795肺腺癌细胞用生理盐水稀释为浓度约3．5×10^7／ml瘤细胞，接种于近交系IRM-1和IRM-2小鼠腋下，0．2ml／只，24h后分别将IRM-1和IRM-2荷瘤小鼠随机分为8组：对照组、单照组、DHEA（低、中、高剂量）组和DHEA（低、中、高剂量）联合照射组。DHEA组与DHEA联合照射组采取腹腔给药，每日1次，连续7d。其中，DHEA联合照射组于给药的第4日进行全身1Gy照射，每日1次，连续5d。观察DHEA联合γ射线照射对小鼠肺腺癌的抑瘤效果及对相关免疫学指标的影响。结果DHEA低、中、高剂量组对IRM-1荷瘤小鼠的抑瘤率分别为38．05％、49．33％和48．18％，与对照组比较差异有统计学意义（担3．417，4．929和4．889，P均〈0．01），联合^137Cs γ射线照射后的抑瘤率分别为56．98％、64．44％和62．72％，与对照组比较差异有统计学意义（t=5．475，5．770和6．165，P均〈0．01）。DHEA低、中、高剂量组对IRM-2小鼠的抑瘤率分别为42．73％、70．91％和67．73％，其中，中、高剂量组与对照组比较差异有统计学意义（t=3．239和3．062，P均〈0．01），联合^137Cs γ射线照射后的抑瘤率分别为63．63％、75．00％和68．64％，与对照组比较差异有统计学意义（t=2．834，3．426和3．156，P分别为〈0．05，〈0．01和〈0．01）。结论DHEA对不同品系小鼠肺腺癌细胞均有抑制作用，联合γ射线照射后的抑瘤疗效比单纯DHEA组更为明显。

英文摘要：

Objective To study the inhibitory effects of 17aα-D-homo ethynylestradiol-3-acetate （DHEA） combined with 137Cs γ-ray irradiation on adenocarcinoma of the lung in different mice strains. Methods The LA795 tumor were diluted by saline to the cell suspension at the concentration of 3.5×10^7/ml. Each IRM-1 and IRM-2 mice was transplanted by armpit injection of 0.2 ml cell suspension. After 24 h, the mice were randomly divided into control group, radiation alone group, DHEA treated groups （high, middle and low dose respectively） and DHEA combined with irradiation groups. Mice in DHEA treated groups and combination groups were intraperitoneally injected with DHEA daily for 7 days. Mice in the combination groups were irradiated with 1 Gy per day for 5 days after injected with DHEA for 4 days. The anti-tumor effects of DHEA combined with irradiation on different group were measured. Results The tumor inhibitory ratios of IRM-1 mice in DHEA treated groups were 38.05% （low does）, 49.33% （middle dose） and 48.18% （high does） respectively, while in combination groups were 56.98% （low does）, 64.44% （middle dose） and 62.72% （high dose）. Compared with control group, the tumor inhibitory ratios in DHEA treated groups （t=3.417, 4.929 and 4.889, all P〈0.01 ） and combination groups （t=5.475, 5.770 and 6.165, all P〈0.01 ） were elevated. The tumor inhibitol~~ ratios of IRM-2 mice in DHEA treated groups were 42.73% （low dose）, 70.91% （middle dose ） and 67.73% （high dose） respectively, while in combination groups were 63.63% （low dose）, 75.00% （middle dose） and 68.64% （high dose）. Compared with control group, the tumor inhibitory ratios in DHEA treated groups （middle and high dose）（t=3.239 and 3.062, both P〈0.01 ）and combination groups （t=2.834, 3.426 and 3.156, P〈0.05, 〈0.01 and 〈0.01） were elevated. Conclusions DHEA showed tumor inhibitory effects on different mice strain transplanted with tumor. The synergistic anti-tumor effects of DHEA and γ