MEDRADSC 2X03 Study Guide - Final Guide: Inelastic Scattering, Elastic Scattering, Radiolysis

• School: McMaster University
• Department: Medical Radiation Sciences
• Course: MEDRADSC 2X03
• Professor: Sandra Charbonneau

Document Summary

2 - interaction of radiation (1. 1 - 1. 2) H20- -> oh- h: h* + 02 -> h02, h20+ -> oh* + h+ Oh* + oh* -> h202 (cytotoxic: 2/3 damage from oh, h20+ + e- -> h20, only time there"s no harm. Restitution - broken ends rejoin, repair enzymes. Each dish dosed w different radiation exposure quantity. All dishes incubated for same time -> counted: does not differentiate b/w apoptotic and mitotic deaths, always log linear graphs (sf log, dose linear, multi-target, multi-hit model. Shoulder - accumulation of single-event damage, repair possible. Straight line (final, "terminal")- multi hit killing, repair not possible: anywhere on straight line - same amount of cells die. High let - no shoulder, straight line. Extrapolation number (n) - measures width of shoulder: mammals n = 2-10, not a true number, an estimation (extrapolated line on y) Quasithreshold dose (dq) - extrapolated linear line would have sf of 1, fake threshold of effect, also measures width.