EFFECTS OF HYPERFRACTIONATED RADIATION ON BONE GROWTH

这项研究的主要目的是探索 分馏和其他潜在影响因素 辐射对生长骨损伤的表达 预测将改善治疗指数的应用程序 儿童恶性肿瘤的治疗。使用老鼠模型，各种 将进行一系列实验，以便：更好地定义 超分割放射治疗计划的组织保留潜力； 阐明分次照射的损伤机制 剂量与分级关系的观察 时间表和各种组织病理学终点；以及研究 剂量、分馏、束流能量和 药物治疗对不同组织修复能力的影响 间室(软骨细胞、微血管系统、骨细胞、 矩阵等)。在这些实验中，组织形态计量学方法 将利用分析来量化组织学 大量标本中的终点。发展和 形态测量技术在辐射测量中的应用 在这个复杂的系统中，剂量-反应关系可以提供 分析辐射引起的正常组织的有用工具 总体上是损坏的。

The primary goal of this study is to explore the role of fractionation and other potentially influential factors in the expression of radiation-induced damage to growing bone to predict appraoches which would improve therapeutic index in the treatment of pediatric malignancies. Using a rat model, a variety of experiments will be performed in order to: better define the tissue-sparing potential of hyperfractionated radiation schedules; clarify the mechanisms of damage of fractionated irradiation by observing the relationship between dose and fractionation schedule and a variety of histopathological endpoints; and study the influence of dose, fractionation, beam energy and concomitant drug therapy on the repair capacity of various tissue compartments (chondrocytes, microvasculature, osteocytes, matrix, et.). In these experiments, histomorphometric methods of analysis will be exploited to permit quantification of histological endpoints in a large number of specimens. Development and application of morphometric techniques to determine radiation dose-response relationships in this complex system may provide a useful tool for the analysis of radiation-induced normal tissue damage in general.