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“癌症”是长期威胁人类健康的三大病魔之一。根据全国肿瘤防治办公室1997年预测,2000年我国死于癌症人数达140万左右,发病人数约为200万,是危害我国人民身体健康的第二大疾病。人类采用了手术切除、化学药物治疗、免疫治疗及近年正在研究的基因疗法等各种手段与之进行了不懈的斗争。放射治疗(即放疗)也是治疗肿瘤的主要手段之一,目前,单独放疗或联合放疗已占整个肿瘤治疗的70%左右,在各种手段的治疗中,以放疗为主的治愈率约占40%。目前采用的放疗手段(X-、r-光子,电子和快中子等)在人体组织内的剂量分布并不理想,在杀死癌细胞的同时,周围健康组织也受到较大损伤,会出现一些并发症。随着核科学技术的发展,人们发现带电重离子在物
“Cancer ” is one of the three major diseases that threaten human health in the long term. According to the 1997 National Cancer Prevention and Treatment Office forecast, in 2000, the number of people dying from cancer in the country was about 1.4 million with a prevalence of about 2 million. It is the second-leading disease that endangers the health of our people. Humans have engaged in unremitting struggles with various means such as surgical resection, chemical drug treatment, immunotherapy and gene therapy under study in recent years. Radiation therapy (ie, radiotherapy) is also one of the main means of treatment of cancer, at present, radiotherapy alone or in combination with radiotherapy has accounted for about 70% of the entire cancer treatment, in various means of treatment, the cure rate of radiotherapy-based accounted for about 40 %. At present, the dose distribution of radiotherapy (X-, r-photon, electron, fast neutron, etc.) in human tissues is not ideal. When the cancer cells are killed, the surrounding healthy tissues are also greatly damaged and appear Some complications. With the development of nuclear science and technology, people found that charged heavy ions in the matter