| Objective : To evaluate the the effect of low dose irradiation on thyms T cell subgroup of rat, and study the outcome of muti-time irradiations.Methods : We gave 0, 1, 2, 3, 4 times low dose total-body irradiation to control group (No. 1 group) and experiment group (No. 2, 3,4,5 group) respectively with γ irradiation .Each dose is 0. 1GY and dose rate is 1.28 cGY/min. The interval of each irradiation is 48 hours . Six hours after every group finished their own total dose , we kill the rats and get their thyme .By using double - parameter direct immune-fluorescence flow cytometry , we detect the expression level of CD3 , CD4 , CD8~+T cell and the change of CD4 /CD8 after whole-body low dose irradiation. Results : (1) The mean of CD3~+T cells in 30 rats thymocyte is 69. 01%. Zero - dose control group' s mean is 61. 87±2. 02%, which is worth lowest; contral group' s CD3~+T cells is increasing according to added irradiation times. NO. 5 group is highest, which is 75. 80 ± 5. 53%. There are significant elevateion between NO. 4 and NO. 1 group, NO. 5 and NO. 1 group, NO. 4 and NO. 2 group, NO. 4 and NO. 3 group, NO. 5 and NO. 2 group, NO. 5 and NO. 3 group (p <0. 05). In all, CD3~+T cell step up gradually by irradiated. (2) The mean of CD4~+T cells in 30 rats thymocyte is 6.06% .Zero... |
