论文部分内容阅读
许多肿瘤中存在的乏氧细胞被认为是某些放射治疗失败的直接原因,设法减小肿瘤组织与正常组织间氧张力的差,可使治疗获得改善。在3～4个大气压纯氧条件下实施放疗,在某些类型肿瘤的治疗中证明有效。缩小氧张力差的另一途径在于降低正常组织的氧含量,对于远端肢体肿瘤可于近端使用止血带造成局部乏氧的状态,对于不在肢端的肿瘤,近年来正在实验呼吸氧含量的混合气体造成全身乏氧的条件,进行低氧放疗。70年代初期,德国和苏联即已开展了这方面的合作研究。实验研究给予低氧混合气体吸入可使小鼠全身照射的致死效应受到很大影响。吸入一个大气压氮分别混以10%和3%的氧的混合气,使LD50/30从1.1增加到2.7,低氧的放射防护效应正是取决于LD50/30的这种变化,这一效应也明显地表现在不同器官的放射反应中。把小鼠骨髓细胞染色体畸变量作为放
The hypoxic cells that are present in many tumors are considered to be the direct cause of failure in some radiation therapies. Trying to reduce the difference in oxygen tension between tumor tissue and normal tissue can lead to improved treatment. Radiotherapy was performed under pure oxygen conditions of 3 to 4 atmospheres, and proved effective in the treatment of certain types of tumors. Another way to reduce the difference in oxygen tension is to reduce the oxygen content of normal tissue. For distal extremity tumors, local tourniquets can be used locally to cause local hypoxia. For non-apical tumors, experimental oxygen content is being mixed in recent years. The gas causes hypoxic conditions throughout the body and hypoxia radiotherapy is performed. In the early 1970s, Germany and the Soviet Union had already conducted cooperative research in this area. The experimental study of hypoxia-inhaled gas inhalation can greatly affect the lethal effect of whole body irradiation in mice. Inhaling a mixture of atmospheric nitrogen and 10% and 3% oxygen, respectively, increases the LD50/30 from 1.1 to 2.7. The effect of hypoxia on radioprotection depends on this change in LD50/30. Obviously manifested in the radiation response of different organs. Take mouse bone marrow cell chromosomal aberrations as