ABSTRACT
Objective The paper reports anti-tumor activities and tumor radio-sensitivity research of the novel Estrogen compound 17a?-D-Homo Ethynylestradiol-3-Acetate to U_ 14 and S_ 180 sarcomas;and overall test high-activity and low toxicity traits of 17a?-D-Homo Ethynylestradiol-3-Acetate by the indexes of thymus gland,spleen,etc.Methods The mouse cervical cancer U_ 14 was selected and implanted in IRM-2 mice for anti-tumor assay,and sarcoma S_ 180 was selected for tumor radio-sensitivity assay,the drug was administered to all mice by i.v.way.Results 17a?-D-Homo Ethynylestradiol-3-Acetate has obvious anti-tumor activity to U_ 14 tumor,the best inhibitory rates is U_ 14 64.3%,and17a?-D-Homo Ethynylestradiol-3-Acetate has hardly any influence to hematogenous system(spleen index),immune system(thymus index);Nevertheless,the positive control drug CCP has obvious damage to spleen index and thymus index(P
ABSTRACT
<p><b>OBJECTIVE</b>To investigate the effect on the dose distribution of source position displacement with the target region margin in catheter-based 192Ir line source endovascular brachytherapy.</p><p><b>METHOD</b>Dose rate distribution along longitudinal axes was estimated by the formula recommended by AAPM No.60 and No. 43.</p><p><b>RESULTS</b>In the two cases of source displacement (1.1 and 5 mm) doses of target region margin was decreased dramatically (at most 53.9% and 565.8% respectively) were compared to that of no source displacement, and the affected range was 6 mm and 9 mm respectively.</p><p><b>CONCLUSION</b>Source displacement will lead to the decrease of dose in target region margin.</p>
Subject(s)
Animals , Brachytherapy , Methods , Coronary Restenosis , Radiotherapy , Coronary Vessels , Radiation Effects , Iridium Radioisotopes , Therapeutic Uses , Radiotherapy DosageABSTRACT
Objective To calculate the mean absorbed doses at celluar and subcellular levels for uniformly and non-uniformly distributed Auger electron emitters. Methods The energy deposited in cell or nucleus by Auger electrons was analytically calculated using the polynomial representation of energy loss.S-values were subsequently computed for several target-source combinations.The absorbed dose and dose distribution were calculated for spherically symmetric radionuclide distributions depending linearly and exponentially on the radial position.The dose profile as a function of the source radial coordinate was also evaluated for typical cell sizes.The contributions of photon radiation to absorbed dose in cells were ignored. Results The mean absorbed dose and dose distribution depend largely on the size of target cells,the radiation spectrum and intracellular localization and distribution of radionuclides.The contribution of intranuclear radionuclides to mean absorbed dose was larger than that of extranuclear ones. Conclusion Auger electrons can produce high local energy deposition in cells because of their very low energies and extremely short ranges.Our dose calculation method is simple.The results are reliable and can be used in many fields.