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Volume 24 (1983)
- Issue 4 Pages 285-
- Issue 3 Pages 197-
- Issue 2 Pages 137-
- Issue 1 Pages 109-
Volume 24, Issue 3
Displaying 1-10 of 10 articles from this issue
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YOSHIHIRO AKIMOTO, TSUGIO SHIROYA, NOBUO EGAMI1983 Volume 24 Issue 3 Pages 197-202
Published: September 15, 1983
Released on J-STAGE: June 16, 2006
JOURNAL FREE ACCESSMorphological abnormalities due to UV partial irradiation to 8 or 16 cell embryos were studied in the sea urchin (Hemicentrotus pulcherrimus) embryo. UV irradiation on the animal hemisphere of 8, 16 cell embryos inhibited normal development at the gastrula stage and caused the formation of exogastrula. UV irradiation of the vegetal hemisphere arrested the normal development at the blastula stage and inhibited the gastrulation and the skeleton formation, giving rise to permanent blastula.View full abstractDownload PDF (354K) -
P. K. GADHIA, V. C. SHAH1983 Volume 24 Issue 3 Pages 203-208
Published: September 15, 1983
Released on J-STAGE: June 16, 2006
JOURNAL FREE ACCESSThe histochemical changes in succinate dehydrogenase were investigated in pectoralis major muscle of pigeon exposed to sub-lethal dose (400 rad) of γ-irradiation. Biochemical study was also carried out after 200, 300 and 400 rad of irradiation. In the present study the overall decrease in enzyme activity could be due to the structural and/or functional damage to mitochondria after treatment of pigeon to different sub-lethal doses of γ-irradiation. The significance of these results has been discussed with special reference to oxidative metabolism.View full abstractDownload PDF (224K) -
JUN SUZUKI, NOBUO EGAMI1983 Volume 24 Issue 3 Pages 209-220
Published: September 15, 1983
Released on J-STAGE: June 16, 2006
JOURNAL FREE ACCESSEffects of ionizing radiation on the earthworm, Eisenia foetida, were investigated by means of mortality, growth inhibition and hatchability of the eggs. Adult earthworms were resistant to 137Cs γ-irradiation, LD50 (30 days) value being about 65 kR. Young earthworms were less resistant than adult ones. Their growth was completely inhibited by 10 kR of γ-irradiation, but 2 kR did not affect them at all. Embryos at early developmental stages showed high mortality by y-irradiation and as development proceeded their resistance to irradiation increased. Mature earthworms were irradiated and the hatchability of the cocoons laid by them after irradiation was examined. Hatchability of the cocoons laid within 5 days after irradiation with 2 kR was scarcely affected. Then the hatchability decreased with the interval between irradiation and laying, and reached lowest level 20 days after irradiation. From 20 days after irradiation, it started to recover and reached the control level 30 days after irradiation.View full abstractDownload PDF (459K) -
YASUKO HYODO-TAGUCHI1983 Volume 24 Issue 3 Pages 221-228
Published: September 15, 1983
Released on J-STAGE: June 16, 2006
JOURNAL FREE ACCESSEmbryos of three different inbred strains and one substrain of Oryzias latipes were irradiated with UV light (25 to 300 J/m2) at the morula stage. Dose-dependent decrease in the surviving fraction was observed in embryos of all strains when examined at optic bud formation stage (Stage 19). It differed, however, in extent among different strains examined. The strain most sensitive to UV light was HO4C, 50% survival dose being 50 J/m2, whereas in HB32C (resistant strain) 50% survival dose as high as 150 J/m2 was found. The survival rates in embryos of all strains were increased by post-irradiation illumination with visible light, the photoreactivable fraction being 0.4 to 0.7. The survival of irradiated embryos when examined at hatching was lower than that examined at Stage 19 in all strains and in this case also, the highest sensitivity to UV of HO4C embryos was clearly demonstrated.View full abstractDownload PDF (306K) -
JUN TAKADA, MASAHARU HOSHI, SHOZOH SAWADA, MASANOBU SAKANOUE1983 Volume 24 Issue 3 Pages 229-236
Published: September 15, 1983
Released on J-STAGE: June 16, 2006
JOURNAL FREE ACCESSUranium isotopes were studied to clarify the fallout from the Hiroshima atomic bomb. The 234U/238U activity ratios of uranium leached from the soil in the Hiroshima fallout area were significantly higher than those of other areas according to alpha ray spectrometry. The correlation of specific activity of the fission product 137Cs and the 234U/238U activity ratios was studied. Two different correlations were established inside and outside the fallout area. The results of this study suggest that manifestations of fallout from the Hiroshima atomic bomb are still detectable in the “black rain” area.View full abstractDownload PDF (268K) -
MASAYOSHI YAMAMOTO, KAZUHISA KOMURA, MASANOBU SAKANOUE1983 Volume 24 Issue 3 Pages 237-249
Published: September 15, 1983
Released on J-STAGE: June 16, 2006
JOURNAL FREE ACCESSConcentrations of 239, 240Pu, 241Am and 137Cs were determined for 30 rice-field surface soil samples in Japan collected from 15 locations mostly in 1963 and 1976, and for 15 soil samples periodically collected from 2 locations during 1957-1980. From the results, the amounts of these radionuclides in rice-field soils and their distribution patterns were made clear, showing that the integrated deposits of these radionuclides on the Japan Sea coast of Honshu is 2.5 to 3 times higher than those on the Pacific coast. Furthermore, the variation of 241Am/239, 240Pu activity ratio with time could be followed well for the soil samples collected during the 24-year period, 1957-1980.View full abstractDownload PDF (465K) -
MASAYOSHI YAMAMOTO, KAZUHISA KOMURA, MASANOBU SAKANOUE1983 Volume 24 Issue 3 Pages 250-258
Published: September 15, 1983
Released on J-STAGE: June 16, 2006
JOURNAL FREE ACCESSConcentrations of 238Pu, 239, 240Pu, 241Pu, 241Am and 137Cs were determined on the soils collected from the Nishiyama area in Nagasaki City where the heaviest fallout from Nagasaki Atomic Bomb had been detected.
And, the contribution of the plutonium derived from Nagasaki Atomic Bomb to the measured total 239, 240Pu in each soil was estimated to be as much as 95 ?? 97% from the activity ratios of 241Pu/239, 240Pu and 241Am/239, 240Pu.View full abstractDownload PDF (303K) -
MINORU INOUYE, YOSHIRO KAMEYAMA1983 Volume 24 Issue 3 Pages 259-269
Published: September 15, 1983
Released on J-STAGE: June 16, 2006
JOURNAL FREE ACCESSInbred F344/DuCrj rats aged 0, 3, 6, 10, 13 and 17 days were exposed to a single wholebody X-irradiation at several dose levels ranging from 3 to 100 rad. They were sacrificed 6 hours after exposure, and their cerebella were removed and processed for microscopic observation. In the mid-sagittal sections through the vermis, the incidence of pyknotic cells among matrix cells in the external granular layer along the primary fissure was estimated. The peak incidences of pyknotic cells were noted following exposure at 10 days of age to any dose levels of irradiation or sham-radiation. For every age-group of treatment the following results were obtained. (1) The incidence of pyknotic cells following exposure to the low dose of 3 rad was significantly higher than for sham-radiation. (2) The incidence was raised with the increased dose (rad); the diagram closely resembles two straight lines with an inflection at 25 rad. (3) The estimated regression coefficient for 3 through 25 rad was smaller than for 25 through 100 rad.View full abstractDownload PDF (714K) -
YASUKO HYODO-TAGUCHI, HISAMI ETOH1983 Volume 24 Issue 3 Pages 270-277
Published: September 15, 1983
Released on J-STAGE: June 16, 2006
JOURNAL FREE ACCESSEggs of the medaka, Oryzias latipes, were irradiated continuously with 137Cs γ-rays at exposure-rates of 10, 100 and 1000 R/day from the morula stage to hatching. Newly hatched fry were transferred to non-irradiation field. At one year after hatching medaka were tested for their fecundity and fertility. When irradiated females were mated with unirradiated males, both the total number of oviposition and number of eggs per oviposition decreased with increasing exposure-rate, whereas almost all the eggs laid were fertilized. However, a decrease in the hatchability of these “normal” eggs was observed in groups of 100 and 1000-R/day exposure-rate. When irradiated males were mated with unirradiated females, an increase in the number of abnormal eggs was obtained in groups of 100 and 1000-R/day exposure-rate, whereas no changes in both the total number of oviposition and number of eggs per oviposition were observed. No change in hatchability of the eggs in this group was also observed even when the highest exposure-rate, i.e., 1000 R/day, was applied.View full abstractDownload PDF (339K) -
M. M. H. GHONEUM, K. IJIRI, M. S. HAMED, O. M. GABR, N. EGAMI1983 Volume 24 Issue 3 Pages 278-283
Published: September 15, 1983
Released on J-STAGE: June 16, 2006
JOURNAL FREE ACCESSThe present study was performed in order to evaluate the state of activity of the taste bud cells of the fish Oryzias latipes. Two types of taste bud cells, namely pale cells and dark cells were distinguished and scored separately. From the irradiation experiment on adult fish, it was found that pale cells were more radiosensitive than are dark cells. At 10 days after irradiation with 1000 R, repopulation of the pale cells was observed and their number returned almost to the control value. In the experiments using various stages of embryos, the formation of the taste bud cells was highly radiosensitive at their early embryonic stages.View full abstractDownload PDF (375K)
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