一、癌瘤的发病率在增长与癌瘤作斗争是关系到保障人类健康和长寿的大事,因此防治癌症已列为现代医学的一项重要课题。癌瘤的发病率正在不断增加,根据1968年的资料,全世界的癌瘤发病率已达到1‰,也就是每百万人中有一千人患癌症。每年死于癌瘤的患者,已增加到将近三百万人。美国一年中有二十万以上的人 First, the increase in the incidence of cancer is a major issue related to the protection of human health and longevity. Therefore, the prevention and treatment of cancer has become an important issue in modern medicine. The incidence of cancer is increasing. According to 1968 data, the incidence of cancer in the world has reached 1 ‰, that is, 1 in 1,000 people suffering from cancer. The number of patients who die of cancer every year has increased to nearly 3 million. In the United States, there are more than 200,000 people in a year