流行病学证据提示,抽烟是人类肺癌的主要病因之一,其机理尚未阐明。已有实验显示:香烟烟雾的冷凝物具有致癌及促癌作用。本文报道香烟烟雾引起人类细胞DNA单链断裂的有关实验,以探求抽烟致癌的机理。将市售带过滤嘴香烟的烟雾通入磷酸盐缓冲液,然后用此液体处理以~(14)C标记胸腺嘧啶核苷的人肺癌细胞。此后立即作染料排除试验,全部细胞仍能排除台盼兰(trypan blue);但将此细胞进行培养则只有50％的平板效率。用碱洗脱技术处理上述细胞后显示:细胞内有大量DNA单链断裂出现,且断链的数量与所用含烟缓冲液的量呈正相关。在此以前作者已发现,通入磷酸盐缓冲液后的 Epidemiological evidence suggests that smoking is one of the major causes of human lung cancer and its mechanism has not been elucidated. Experiments have shown that the condensation of cigarette smoke has carcinogenic and carcinogenic effects. This article reports on cigarette smoke caused by human cell DNA single strand breaks related experiments to explore the mechanism of smoking carcinogenesis. Commercially available smoked cigarettes were passed through phosphate buffered saline and then treated with ~ (14) C thymidine in human lung cancer cells. Dye exclusion tests were performed immediately thereafter, with all cells still able to exclude trypan blue; however, culturing the cells resulted in only a 50% plate efficiency. Treatment of these cells with alkaline eluting techniques revealed that a large number of single-stranded DNA breaks were present in the cells, and the number of scission chains was positively correlated with the amount of smoke-containing buffer used. Prior to this, the authors have found that after phosphate buffered saline is introduced