1、RadiobiologyPart OneBME College Sherman Sheen(辛學(xué)剛)The Physics of Radiology第1頁(yè)，共16頁(yè)。four Rs the repair of sublethal damagerepopulation by surviving cells in the irradiated tissuesredistribution of cells throughout the division cyclereoxygenation of hypoxic cells第2頁(yè)，共16頁(yè)。Initial EventThe Passage of th

2、e Charged Particles EFFICIENCY of RADIATION DAMAGE TRACKS of CHARGED PARTICLES 第3頁(yè)，共16頁(yè)。DISTRIBUTIONS IN SPACE of ENERGY RELEASES LINEAR ENERGY TRANSFER (LET) the electron tracks 0.25 keV/m an alpha particle 250 keV/m SPECTRUM OF LET VALUES velocity charge 第4頁(yè)，共16頁(yè)。IMMEDIATE RADIOCHEMICAL EFFECT Pro

3、duction of Solvated Electrons and Radicals第5頁(yè)，共16頁(yè)。Dependence of Radiation Damage on LET the radiobiological equivalent (RBE) the relative efficiency of killing第6頁(yè)，共16頁(yè)。ASSAYS FOR PROLIFERATIVE CAPACITYSURVIVAL CURVES COLONY ASSAY METHODIN VITRO IN VIVO ASSAYS spleen-colony method Limiting dilution

4、assayIn situ第7頁(yè)，共16頁(yè)。第8頁(yè)，共16頁(yè)。ASSAYS FOR PROLIFERATIVE CAPACITYSURVIVAL CURVES COLONY ASSAY METHODIN VITRO IN VIVO ASSAYS spleen-colony method Limiting dilution assayIn situ第9頁(yè)，共16頁(yè)。MATHEMATICAL ASPECTS OF SURVIVAL CURVES SINGLE HIT SURVIVAL CURVE The mean lethal dose (D0) is the dose required to re

5、duce the population of entities from any value N to 0.37 N 第10頁(yè)，共16頁(yè)。MULTI-TARGET SINGLE HIT SURVIVAL CURVE 第11頁(yè)，共16頁(yè)。THERAPEUTIC RATIO where D2 is the dose that leads to serious complications in 50% of the patients D2/D1and D1 is the dose that gives tumor control inthe same % of patients. 第12頁(yè)，共16頁(yè)

6、。RADIOBIOLOGICAL EQUIVALENT (RBE) RBE =Dose from standard radiation to produce a given biological effectDose from the test radiation to produce the same biological effect第13頁(yè)，共16頁(yè)。第14頁(yè)，共16頁(yè)。CELL CYCLE AND RADIOSENSITIVITY 第15頁(yè)，共16頁(yè)。Summary four Rs EFFICIENCY of RADIATION DAMAGE TRACKS of CHARGED PARTICLES IMMEDIATE RADIOCHEMICAL EFFECT ASSAYS FOR PROLIFERATIVE CAPACITYSURVIVAL CURVES MATHEMATICAL ASPECTS OF SURVIVAL