RESUMEN
There are differences and inconsistencies to some degree in the radioactive contamination control level of personnel′s body surface availiable in many national standards, thus puzzling the users. Therefore, it is proposed to compare the applicable scope, conditions and differences between relevant national standards, and combine with similar clinical nuclear medicine standards of radiological protection content to presevent recommendations on the contamination control level that should be correctly applied in an event of nuclear and radiological emergency. Based on the discussion of similar standards, the contaminated personnel with α of 0.04-10 Bq/cm 2 and β of 0.4-100 Bq/cm 2 are advised to be treated in the institutions with higher than secondary medical insititution. Both α econtamination control levels less than 0.04 Bq/cm 2 and β levels less than 0.4 Bq/cm 2 could be achivable, if fully decontaminated.
RESUMEN
Objective To investigate the application prospective of carboxyfullerene C_3 as a radioprotectant or assistant for tumor radiotherapy.Methods Different concentrations of C_3 were incubated with K562 and AHH-1 cell,CCK-8 assay and trypan blue rejection test were performed to examine the influence of C_3 on the cell viability.Annexin V/PI staining and flow cytometry assay were applied to assess the cell cycle and apoptosis after 7-ray irradiation.Results C_3 showed little toxicity to AHH-1 cell with the survival rate over 95% ,but 600 mg/L of C_3 markedly inhibited the growth of K562 cell (82%) .Pretreatment of 100 mg/L C_3 significantly increased the survival rate of AHH-1 cell after 4 Gy irradiation compared with the single radiation group(71.3% vs 90.3%) ,but decreased the apoptosis rate (26.3% vs 12.6%) ,while the survival rate of K562 cell was decreased and the apoptosis rate was elevated with the increase of C_3 concentration.Moreover,the cell cycle analysis revealed the G_2 phase block in AHH-1 cell after radiation exposure was mitigated by C_3 pretreatment,but that in K562 cell was aggravated.Conclusions C_3 has good radioprotective effects on AHH-1 cells.For K562 cell,C_3 could inhibit the cell proliferation,promote the radiation induced apoptosis and aggravate the G_2 phase block.