Dose response characteristics of polyvinyl alcohol (PVA) films (thickness: about 20μm) dyed with methylene blue (MB) or methyl orange (MO) were studied and these films were applied to depthdose profile measurements for low-energy electrons (150 - 300 ke V) . Dose responses were measured in terms of optical density change of spectral peak at 662 and 434 nm for MB/PVA and MO/PVA, respectively. The dose response curves show good linearity in kGy dose-range up to about 30 kGy for MB/PVA film and to about 300 kGy for MO/PVA film. The measured depth-dose profiles were in relatively good agreement with those obtained by calculations using EDMULT code.
PMMA dosimeters are widely used for high dose dosimetry. Dose is determined by measuring the change in optical density of the irradiated PMMA dosimeter element. Measurement precision depends on the mounting method of a dosimeter element in the sample room of a spectrophotometer. We tried to prepare three types of holders, (holders A, B and C in Figs. 1-3), according to the shape of PMMA dosimeter elements. We measured optical density of the irradiated PMMA dosimeter elements by using the three types of holders. It is revealed that the holder of the type A gives more precise results for the Red 4034 or Gammachrome YR dosimeter than that of the type B. The measurements with a spectrophotometer using the type C holder gives better results for the Red acrylic dosimeter than the case of the measurements by the exclusive reader.
We performed the basic evaluation of an immunoradiometric assay kit for serum thyroid stimulating hormone“Ab bead TSH kit EIKEN”, and compared its results with those examined by“SPA C-S TSH kit”and“RIA-gnost®tTSH.”In reproducibility of the intra- and inter-assay variance, dilution test and recovery test, good results were obtained in all of them by all kits. The TSH values measured by 3 kits significantly correlated (γ= 0.99) . Normal range of TSH values caliculated from the examination of the healthy controls were 0.32-4.51μU/ml by“Ab bead TSH kit EIKEN”, 0.36-4.96 μU/ml by“SPA C-S TSH kit”and 0.23 - 2.68, μU/ml by“RIA-gnost®tTSH”. In conclusion, these data indicated that“Ab bead TSH kit EIKEN”is very useful for measurement of the serum thyroid stimulating hormone.