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  • 28 June 2001 Volume 10 Issue 2
      
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  • Study of the Computed Tomography Dose Index
    CHENG Qi-jun, ZHANG Zeng, ZHU Fu-min, et al
    2001, 10(2): 65-66.
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    Objective The impact on the computed tomography dose index (CTDI) value of varying integrating lengths (±7 T and ±50 mm) is analyged.Methods A Hitachi W-1000 scanner was used with thermoluminescent dosimeters and computed tomography dosimetry phantoms.The dose profiles are measured for single scan and the corresponding CTDI calculated for varying integrating lengths.Results For slice thickness over 7 mm (10 mm), the CTDI100 value obtained with ±50 mm of integrating length will underestimate the CTDIF.By contrast, for the slice thickness below 7 mm (5 mm), the CTDI100 will overestimate the CTDIF.Conclusion The differences between CTDI100 value and CTDIF are presented for varying slice thickness.The measured CTDI100 value should be corrected fo r different slice thickness when using a pencil ionization chamber.
  • The Radioprotective Effect of Polysaccharides of Huangmo and its Mechanism
    JIANG Shi-quan, YE Fei, SU Shi-jie, et al
    2001, 10(2): 67-68.
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    The radioprotective effect of polysaccharides of Huangmo (PSH) and its effects on LPO content and SOD、GSH-PX and CAT activities of liver in irradiated mice were studied.The results showed that the 30-day survival rate of mice after 8.0 Gy X-ray irradiation increased significantly when the mice were injected with PSH before irradiation, and the survival days were delayed, the protection index was 1.32.Meanwhile, the effect of PSH was similar to polysaccharides of Ginseng (PSG).We in our further study found that PSH lowered LPO content in the liver of mice 72h after 8.0 Gy X-irradiation, and increased the activities of SOD、GSH-P and CAT.The results suggest that PSH has an obvious radioprotective effect, and its possible mechanism is that PSH may be a scavenger of free radicals, and can suppress or stop the reactions of lipid peroxidation.
  • Study on Radioprotective Effect of Occupational Healthy-Tea No 4
    YAN Yong-jian, CHEN Yu-li, WANG Shu-zhen, et al
    2001, 10(2): 69-70.
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    Objective To observe the radiation protection effect of Occupational Healthy-tea No 4 (OHT4) against injury by X-ray in mice.Methods 45 male mice of Kunming strain were divided randomly into 3 groups:① normal control, ② irradiated model group and ③ the experimental grouop.Mice of groups ② ③ were irradiated once with 6.0 GyX-ray (2.0 Gy/min), meanwhile the mice of group ③ were treated with 2 mg/g.bw of OHT4.Then the difference of survival rate and the changes of WBC、PLT、T-cells subgroups between 3 groups were observed.Results The OHT4 could lessen the radiation injury of X-ray and enhance the survival rate, the number of blood cells and T-cell immune function in mice.Conclusion OHT4 has the significant protective effect against X-ray radiation.