著者
熊谷 エツ子 田中 龍二 熊谷 崇 東田 善治 尾道 三一 中村 郁夫 田上 省三 甲木 孝人 澤田 昭三
出版者
Journal of Radiation Research 編集委員会
雑誌
Journal of Radiation Research (ISSN:04493060)
巻号頁・発行日
vol.29, no.3, pp.203-210, 1988-09-15 (Released:2006-06-16)
参考文献数
28
被引用文献数
3 1 4

To clarify the long-term effects of occupational exposure to low doses of radiation, Epstein-Barr virus (EBV)-specific antibody titers in sera from 104 radiological technologists (R.T.) and 118 controls in Kumamoto prefecture were measured by the immunofluorescence method. Antibody titers to viral capsid antigen (VCA)-IgG increased with the years of experience as R.T., and the prevalence of abnormal antibody titers to both VCA-IgG and early antigen (EA)-IgG were significantly higher in R.T. with over 15 years of experience or 30 rads of cumulative radiation dose than in the controls. However, there was no correlation between exposure and the frequency of abnormal EBV-associated nuclear antigen (EBNA) antibody titers. The EBV-specific antibody titers of 24 Hiroshima atomic-bomb survivors were also measured. They were similar to those of the R.T. with over 30 years of experience. The EBV-specific antibody titers of R.T. suggest that there may be an impairment of immunologic competence after continuous long-term exposure to low doses of radiation. Also, the correlation of EBV-specific antibody titers and frequency of cells with chromosome aberrations in 53 R.T. was studied. Some correlations were found between the antibody titers to both of the VCA-IgG and EBNA and the frequency of cells with chromosome aberrations.
著者
MITOSHI AKIYAMA YOICHIRO KUSUNOKI SEISHI KYOIZUMI
出版者
Journal of Radiation Research 編集委員会
雑誌
Journal of Radiation Research (ISSN:04493060)
巻号頁・発行日
vol.32, no.SUPPLEMENT, pp.301-309, 1991 (Released:2006-05-31)
参考文献数
38
被引用文献数
3 3

Among the peripheral blood lymphocytes, T-cells and B-cells significantly decreased in number with age. Radiation exposure resulted in further significant decrease of T-cell count (but not B cells) in the elderly. T-cell response to PHA and allo-antigens also decreased with dose in the elderly group. In contrast, NK cell number and function increased with age while a significant dose effect was not observed.
著者
常岡 和子 HIROSHI ISHIHARA ALEXANDER BORRISOV DIMCHEV KOJI NOMOTO TERUO YOKOKURA MIKIO SHIKITA
出版者
Journal of Radiation Research 編集委員会
雑誌
Journal of Radiation Research (ISSN:04493060)
巻号頁・発行日
vol.35, no.3, pp.147-156, 1994-09-15 (Released:2006-05-19)
参考文献数
25
被引用文献数
9 14

A single subcutaneous injection of a preparation of heat-killed Lactobacillus casei (LC 9018), given before or after irradiation, significantly increased the survival rate of mice that had received 8.5-Gy 137Cs whole-body γ-irradiation. A similar radioprotective effect was observed when LC 9018 was administered within the period from 2 days before irradiation to 9 h after irradiation, the pre-irradiation treatment being slightly better than the post-irradiation treatment. Increases in the weight of the spleen and in the number of endogenous spleen colonies on days 8 and 12 after irradiation suggested that the radioprotective effect was based on enhanced recovery of hematopoietic tissues. The activity of macrophage colony-stimulating factor (M-CSF) in serum was rapidly increased by the treatment and was maintained at the elevated level for 13 days. At the same time, an increased level of M-CSF mRNA was detected in the livers of the treated mice. However, LC 9018 failed to save the lives of mice when administered 3 days after irradiation, although it increased serum M-CSF as effectively as noted above. The small advantage of the pre-irradiation over the post-irradiation treatment was not explained by the increases of metallothionein in the hematopoietic tissues of the treated mice.
著者
定家 義人 井上 正 望月 肇 賀田 恒夫
出版者
Journal of Radiation Research 編集委員会
雑誌
Journal of Radiation Research (ISSN:04493060)
巻号頁・発行日
vol.22, no.4, pp.387-394, 1981
被引用文献数
2

When spores of Bccillus subtilis were treated in a frozen state with tritiated glycerol of different concentrations (up to 160 &mu;Ci/ml), efficiencies of killing and mutation induction per absorption dose were higher in solutions of lower tritium concentrations where low dose-rate &beta;-irradiations were performed. Similarly when transforming DNA of Bacillus subtilis was kept with tritiated glycerol solution of concentrations ranging 0.05-500 &mu;Ci/ml at 4&deg;C, efficiency of inactivation of the arginine marker increased strikingly by lowering the tritium concentration. On the other hand, the RBE of DNA-strand scissions of colicin El plasmids exposed to tritiated glycerol of a relatively high concentration (680 &mu;Ci/ml) was found to be approximately 1, when compared at the same absorption dose of gamma-irradiation (36 kR/hr) from a <SUP>137</SUP>Cs source.
著者
Sun Lue Moritake Takashi Zheng Yun-Wen Suzuki Kenshi Gerelchuluun Ariungerel Hong Zhengshan Zenkoh Junko Taniguchi Hideki Tsuboi Koji
出版者
Oxford University Press
雑誌
Journal of radiation research (ISSN:04493060)
巻号頁・発行日
vol.54, no.1, pp.61-69, 2013-01
被引用文献数
13

One-third of patients with medulloblastoma die due to recurrence after various treatments including radiotherapy. Although it has been postulated that cancer stem-like cells are radio-resistant and play an important role in tumor recurrence, the “stemness” of medulloblastoma cells surviving irradiation has not yet been elucidated. Using a medulloblastoma cell line ONS-76, cells that survived gamma irradiation were investigated on their “stemness” in vitro. From 10 500 cells, 20 radio-resistant clones were selected after gamma ray irradiation (5 Gy × two fractions) using the replica micro-well technique. These 20 resistant clones were screened for CD133 positivity by flow cytometry followed by side population assay, tumor sphere formation assay and clonogenic survival assay. Results revealed CD133 fractions were significantly elevated in three clones, which also exhibited significantly increased levels of tumor sphere formation ability and side population fraction. Clonogenic survival assay demonstrated that their radio-resistance was significantly higher than the parental ONS-76. This may support the hypothesis that a small number of cancer stem-like cells (CSCs) are the main culprits in local recurrence after radiotherapy, and disruption of the resistance mechanism of these CSCs is a critical future issue in improving the outcome of patients with medulloblastoma.
著者
井上 稔 早坂 静 孫 学智 山村 英樹
出版者
日本放射線影響学会
雑誌
Journal of Radiation Research (ISSN:04493060)
巻号頁・発行日
vol.34, no.3, pp.204-213, 1993-09
被引用文献数
7 17

We show that neuronal migration is disturbed by low-dose gamma-radiation of 0.24 Gy in the developing cerebral cortex of mice and suggest that neuronal progenitors in the S phase of mitosis are more sensitive than those in the G_1/G_0 phase. To pulse-label the fetal cells pregnant Slc ICR mice were injected with bromodeoxyuridine (BrdU) at 10.00 pm on day 16 of pregnancy or at 9.30 am on day 17. The mice then were exposed to 0.24 Gy gamma- or sham-irradiation at 10.00 am on day 17 of pregnancy. At the time of exposure cells labeled on day 16 were regarded as having completed mitosis, and those labeled on day 17 as being in the S phase. Cell death in the fetal ventricular zone after exposure was negligible. Dams were allowed to give birth and rear their litters. Brain samples obtained from offspring on the 2nd day after birth and at 6 weeks of age were used for the immunohistochemical examination of BrdU-labeled cells.
著者
山県 登 岩島 清 永井 輝夫 渡利 一夫 飯沼 武
出版者
Journal of Radiation Research 編集委員会
雑誌
Journal of Radiation Research (ISSN:04493060)
巻号頁・発行日
vol.7, no.1, pp.29-46, 1966 (Released:2006-08-29)
参考文献数
13
被引用文献数
9 13

Two single doses of coupled radioisotopes of 132Cs-86Rb and 132Cs-42K were orally administered to a human subject. Body retention, urinary and fecal excretions as well as the plasma and erythrocytes contents of radioisotopes were determined. The proportion of urinary to fecal excretion was found different in cesium and rubidium, the urinary excretion being 85.3% of the total in the former and only 68.1% in the latter. Loss of cesium in the sweat amounted to 1.5 and 3.5% of the total excretion for the first two days. Uptake by the plasma of oral dose was rapid and the whole blood content reached max. 11.4% of the dose of cesium at 1 hour, while 2.9 and 2.4% respectively of rubidium and potassium was reached. The levels in the erythrocytes seemed to grow at a slower rate in cesium than in the other alkali elements. The different feature of blood metabolism found in the alkali elements was interpreted by the slow rate of clearance of ingested cesium from blood. Daily fluctuations of fall-out 137Cs in blood and the errors involved in the assessment of the total body burden of 137Cs by blood analysis were also discussed.
著者
田中 義一郎 河村 曰佐男
出版者
Journal of Radiation Research 編集委員会
雑誌
Journal of Radiation Research (ISSN:04493060)
巻号頁・発行日
vol.19, no.1, pp.78-84, 1978-03-15 (Released:2006-07-14)
参考文献数
14
被引用文献数
7 12 11

As a method of prompt and rapid estimation of thyroidal 131I burden of the public (and nuclear workers) in emergency exposure to radioiodine, feasibility of a use of a scintillation survey meter with a NaI (T1) crystal was demonstrated using phantoms simulating the thyroid gland of Japanese. Age dependency in the efficiency of detection was found. From the obtained detection limit, a possibility of the practical application of this method was proven. The present method may be safely used in rapid screening and measurement to a first approximation of the thyroidal 131I burden and consequently approximation of absorbed dose to the thyroid gland in emergency situations.
著者
山県 登
出版者
Journal of Radiation Research 編集委員会
雑誌
Journal of Radiation Research (ISSN:04493060)
巻号頁・発行日
vol.3, no.1, pp.9-30, 1962-03-01 (Released:2006-08-29)
参考文献数
10
被引用文献数
27 41

Measurements have been made of potassium, rubidium and cesium in the human soft tissues, muscles and bones from autopsies to determine the normal concentrations of these elements and to estimate the total body amount. The individual variability of concentration increases in the following order : K Rb Cs and the distribution pattern of potassium in muscle suggests a normal distribution and the observed distribution of stable cesium and the Cs/K ratio in muscle appear to be lognormal. A fairly good agreement is observed in rubidium data with those reported by other workers, however, discrepancy in cesium data is observed between the author and other workers. The amount of potassium, rubidium and cesium in the total body estimated from the concentrations of these elements in the soft tissues, muscle and bone is, respectively, 136±28 grams, 0.36±0.09 grams and 1.4 × 10-3 grams (95% probable range : 0.50—4.1 × 10-3) for the standard man of 70 kg body weight.
著者
Naoki HAYASHI Satoru MONZEN Koichi ITO Tsuyoshi FUJIOKA Yukio NAKAMURA Ikuo KASHIWAKURA
出版者
Journal of Radiation Research Editorial Committee
雑誌
Journal of Radiation Research (ISSN:04493060)
巻号頁・発行日
vol.53, no.2, pp.195-201, 2012 (Released:2012-04-17)
参考文献数
28
被引用文献数
8

The present study aimed to estimate the clonogenic and differentiation potential of induced pluripotent stem (iPS) cells exposed to ionizing radiation. Compared with mouse hematopoietic stem/progenitor cells, iPS cells were less sensitive to radiation. To examine the effect of ionizing radiation on the early differentiation pathway of iPS cells, we assessed embryoid body (EB) formation. Although EB formation was observed at all radiation doses, EB diameter decreased in a radiation dose-dependent manner. At the same time, we analyzed the expression of genes specific to differentiation in the initial iPS cells and cells of EB. The expression of the endoderm marker Afp increased remarkably in cells of EB derived from non-irradiated iPS cells; however, in irradiated cells, this expression significantly decreased in a radiation dose-dependent manner. Further, the expressions of the pluripotent stem cell markers Nanog and Oct-4 and the early mesoderm marker Brachyury significantly decreased. The results of the present study suggest that radiosensitivity with regard to gene expression differs at various stages in the early differentiation pathways of iPS cells that lead to the formation of the 3 germ layers; the sensitivity is the highest in the genes expressed during the differentiation pathways of iPS cells, leading to the formation of the endoderm.
著者
Megumi HADA Alexandros G. GEORGAKILAS
出版者
Journal of Radiation Research Editorial Committee
雑誌
Journal of Radiation Research (ISSN:04493060)
巻号頁・発行日
vol.49, no.3, pp.203-210, 2008 (Released:2008-05-21)
参考文献数
79
被引用文献数
359

Radiation can cause as well as cure cancer. The risk of developing radiation-induced cancer has traditionally been estimated from cancer incidence among survivors of the atomic bombs in Hiroshima and Nagasaki.1) These data provide the best estimate of human cancer risk over the dose range for low linear energy transfer (LET) radiations, such as X- or γ-rays. The situation of estimating the real biological effects becomes even more difficult in the case of high LET particles encountered in space or as the result of domestic exposure to α-particles from radon gas emitters or other radioactive emitters like uranium-238.Complex DNA damage, i.e., the signature of high-LET radiations comprises of closely spaced DNA lesions forming a cluster of DNA damage. The two basic groups of complex DNA damage are double strand breaks (DSBs) and non-DSB oxidative clustered DNA lesions (OCDL). Theoretical analysis and experimental evidence suggest an increased complexity and severity of complex DNA damage with increasing LET (linear energy transfer) and a high mutagenic or carcinogenic potential. Data available on the formation of clustered DNA damage (DSBs and OCDL) by high-LET radiations are often controversial suggesting a variable response to dose and type of radiation. The chemical nature and cellular repair mechanisms of complex DNA damage have been much less characterized than those of isolated DNA lesions like an oxidized base or a single strand break especially in the case of high-LET radiation. This review will focus on the induction of clustered DNA damage by high-LET radiations presenting the earlier and recent relative data.
著者
Masao SUZUKI Chizuru TSURUOKA Yukio UCHIHORI Hisashi KITAMURA Cui Hua LIU
出版者
Journal of Radiation Research Editorial Committee
雑誌
Journal of Radiation Research (ISSN:04493060)
巻号頁・発行日
vol.50, no.5, pp.395-399, 2009 (Released:2009-09-16)
参考文献数
23
被引用文献数
2

We studied cellular responses in normal human fibroblasts induced with low-dose (rate) or low-fluence irradiations of different radiation types, such as gamma rays, neutrons and high linear energy transfer (LET) heavy ions. The cells were pretreated with low-dose (rate) or low-fluence irradiations (~1 mGy/7-8 h) of 137Cs gamma rays, 241Am-Be neutrons, helium, carbon and iron ions before irradiations with an X-ray challenging dose (1.5 Gy). Helium (LET = 2.3 keV/μm), carbon (LET = 13.3 keV/μm) and iron (LET = 200 keV/μm) ions were produced by the Heavy Ion Medical Accelerator in Chiba (HIMAC), Japan. No difference in cell-killing effect, measured by a colony forming assay, was observed among the pretreatment with different radiation types. In mutation induction, which was detected in the hypoxanthine-guanine phosphoribosyltransferase (hprt) locus to measure 6-thioguanine resistant clones, there was no difference in mutation frequency induced by the X-ray challenging dose between unpretreated and gamma-ray pretreated cells. In the case of the pretreatment of heavy ions, X-ray-induced mutation was around 1.8 times higher in helium-ion pretreated and 4.0 times higher in carbon-ion pretreated cells than in unpretreated cells (X-ray challenging dose alone). However, the mutation frequency in cells pretreated with iron ions was the same level as either unpretreated or gamma-ray pretreated cells. In contrast, it was reduced at 0.15 times in cells pretreated with neutrons when compared to unpretreated cells. The results show that cellular responses caused by the influence of hprt mutation induced in cells pretreated with low-dose-rate or low-fluence irradiations of different radiation types were radiation-quality dependent manner.Translated and modified from Radiat. Biol. Res. Comm. Vol.43(4); 424-435, (2008, in Japanese).
著者
Imanaka Tetsuji Fukutani Satoshi Yamamoto Masayoshi SAKAGUCHI Aya HOSHI Masaharu
出版者
日本放射線影響学会
雑誌
Journal of radiation research (ISSN:04493060)
巻号頁・発行日
vol.47, pp.A121-A127, 2006-02
被引用文献数
3 15

Dolon village, located about 60 km from the border of the Semipalatinsk Nuclear Test Site, is known to be heavily contaminated by local fallout from the first USSR atomic bomb test in 1949. External radiation in Dolon was evaluated based on recent 137Cs data in soil and calculation of temporal change in the fission product composition. After fitting a log-normal distribution to the soil data, a 137Cs deposition of 32 kBq m-2, which corresponds to the 90th-percentile of the distribution, was tentatively chosen as a value to evaluate the radiation situation in 1949. Our calculation indicated that more than 95% of the cumulative dose for 50 y had been delivered within 1 y after the deposition. The resulting cumulative dose for 1 y after the deposition, normalized to the initial contamination containing 1 kBq m-2 of 137Cs, was 15.6 mGy, assuming a fallout arrival time of 3 h and a medium level of fractionation. Finally, 0.50 Gy of absorbed dose in air was derived as our tentative estimate for 1-year cumulative external dose in Dolon due to local fallout from the first USSR test in 1949.
著者
Nakashi SASANO Atsushi ENOMOTO Yoshio HOSOI Yosuke KATSUMURA Yoshihisa MATSUMOTO Kenshiro SHIRAISHI Kiyoshi MIYAGAWA Hiroshi IGAKI Keiichi NAKAGAWA
出版者
Journal of Radiation Research Editorial Committee
雑誌
Journal of Radiation Research (ISSN:04493060)
巻号頁・発行日
vol.48, no.6, pp.495-503, 2007 (Released:2007-11-21)
参考文献数
58
被引用文献数
20

Edaravone, a clinical drug used widely for the treatment of acute cerebral infarction, is reported to scavenge free radicals. In the present study, we investigated the radioprotective effect of edaravone on X-ray-induced apoptosis in MOLT-4 cells. Apoptosis was determined by the dye exclusion test, Annexin V binding assay, cleavage of caspase, and DNA fragmentation. We found that edaravone significantly suppressed the X-ray-induced apoptosis. The amount of intracellular ROS production was determined by the chloromethyl-2',7'-dichlorodihydro-fluorescein diacetate system. We found that the intracellular ROS production by X-irradiation was completely suppressed by the addition of edaravone. The accumulation and phosphorylation of p53 and the expression of p21WAF1, a target protein of p53, which were induced by X-irradiation, were also suppressed by adding edaravone. We conclude that the free radical scavenger edaravone suppresses X-ray-induced apoptosis in MOLT-4 cells by inhibiting p53.
著者
Yasuyuki TAIRA Naomi HAYASHIDA Gopalganapathi M. BRAHMANANDHAN Yuji NAGAYAMA Shunichi YAMASHITA Jumpei TAKAHASHI Alexander GUTEVITC Alexander KAZLOVSKY Marat URAZALIN Noboru TAKAMURA
出版者
Journal of Radiation Research Editorial Committee
雑誌
Journal of Radiation Research (ISSN:04493060)
巻号頁・発行日
vol.52, no.1, pp.88-95, 2011 (Released:2011-01-29)
参考文献数
24
被引用文献数
25

To evaluate current environmental contamination and contributions from internal and external exposure due to the accident at the Chernobyl Nuclear Power Plant (CNPP) and nuclear tests at the Semipalatinsk Nuclear Testing Site (SNTS), concentrations of artificial radionuclides in edible mushrooms, soils and stones from each area were analyzed by gamma spectrometry. Annual effective doses were calculated for each area from the cesium contamination. Calculated internal effective doses of 137Cs due to ingestion of mushrooms were 1.8 × 10–1 mSv/year (y) in Gomel city (around CNPP), 1.7 × 10–1 mSv/y in Korosten city (around CNPP), 2.8 × 10–4 mSv/y in Semipalatinsk city, and 1.3 × 10–4 mSv/y in Nagasaki. Calculated external effective doses of 137Cs were 3.4 × 10–2 mSv/y in Gomel city, 6.2 × 10–2 mSv/y in Korosten city, 2.0 × 10–4 mSv/y in Semipalatinsk city, and 1.3 × 10–4 mSv/y in Nagasaki. Distribution of radionuclides in stones collected beside Lake Balapan (in SNTS) were 241Am (49.4 ± 1.4 Bq/kg), 137Cs (406.3 ± 1.7 Bq/kg), 58Co (3.2 ± 0.5 Bq/kg), and 60Co (125.9 ± 1.1 and 126.1 ± 1.1 Bq/kg). The present study revealed that dose rates from internal and external exposure around CNPP were not sufficiently low and radiation exposure potency still exists even though current levels are below the public dose limit of 1 mSv/y (ICRP1991). Moreover, parts of the SNTS area may be still contaminated by artificial radionuclides derived from nuclear tests. Long-term follow-up of environmental monitoring around CNPP and SNTS, as well as evaluation of health effects in the population residing around these areas, may contribute to radiation safety with a reduction of unnecessary exposure of residents.
著者
田中 公夫 鎌田 七男 大北 威 蔵本 淳
出版者
日本放射線影響学会
雑誌
Journal of Radiation Research (ISSN:04493060)
巻号頁・発行日
vol.24, no.4, pp.291-304, 1983-12
被引用文献数
1 25

The distribution of breakpoints within chromosomes in lymphocytes of 39 healthy atomic bomb survivors who were heavily exposed were studied by means of G- and Q-banding techniques. A total of 1,414 breakpoints in 651 cells with structural chromosome aberrations were used for the present analyses. The results obtained were as follows: (1) In chromosomes #15, #18 and #22, the breaks were more frequently observed than expected. On the contrary, the number of breaks among chromosomes #1, #2 and X was less than expected. (2) A higher incidence of breakpoints according to the length of regions in 4q3, 5q3 and 14q3 and a lower incidence in regions around centromeres of large chromosomes were observed. (3) Distribution of breakpoints was 26.6% in the centromeric region, 30.8% in the middle region and 42.6% in the telomeric region. (4) Seventy-four percent of the breaks was observed in the negative bands.
著者
熊谷 エツ子 田中 龍二 熊谷 崇 東田 善治 尾道 三一 中村 郁夫 田上 省三 甲木 孝人 澤田 昭三
出版者
日本放射線影響学会
雑誌
Journal of Radiation Research (ISSN:04493060)
巻号頁・発行日
vol.29, no.3, pp.203-210, 1988-09
被引用文献数
1 1

To clarify the long-term effects of occupational exposure to low doses of radiation, Epstein-Barr virus (EBV)-specific antibody titers in sera from 104 radiological technologists (R.T.) and 118 controls in Kumamoto prefecture were measured by the immunofluorescence method. Antibody titers to viral capsid antigen (VCA)-IgG increased with the years of experience as R.T., and the prevalence of abnormal antibody titers to both VCA-IgG and early antigen (EA)-IgG were significantly higher in R.T. with over 15 years of experience or 30 rads of cumulative radiation dose than in the controls. However, there was no correlation between exposure and the frequency of abnormal EBV-associated nuclear antigen (EBNA) antibody titers. The EBY-specific antibody titers of 24 Hiroshima atomic-bomb survivors were also measured. They were similar to those of the R.T.with over 30 years of experience. The EBV-specific antibody titers of R.T. suggest that there may be an impairment of immunologic competence after continuous long-term exposure to low doses of radiation. Also, the correlation of EBV-specific antibody titers and frequency of cells with chromosome aberrations in 53 R.T. was studied. Some correlations were found between the antibody titers to both of the VCA-IgG and EBNA and the frequency of cells with chromosome aberrations.
著者
渡辺 敦光 岡本 太郎 山田 和正 安東 保海 伊藤 明弘 星 正治 澤田 昭三
出版者
日本放射線影響学会
雑誌
Journal of Radiation Research (ISSN:04493060)
巻号頁・発行日
vol.34, no.3, pp.235-239, 1993-09
被引用文献数
2 2

The effects of the dose rate and the energy of fission neutrons using an iron block on tumorigenesis in B6C3F1 mice were examined. Six-week-old female animas were divided into 4 groups and exposes to ^<252>Cf neutron irradiation at dose rates of 0.05 cGy/min, with (Group 1) or without (Group 2) filtering through a 10 cm thick iron block, 0.8 cGy/min (Group 3) or 0 (Group 4 controls). Total neutron exposure was 50 cGy in each of groups 1-3 and total irradiation dose was 56,75 and 75 cGy in Groups 1-3, respectively. Total tumor incidences or multiplicity were significantly higher in Group 3 than in Group 1. A similar tendency was observed as compared to Group 2, ovarian and Harderian gland tumors being mainly affected and adrenal tumors were significantly higher in Group 2 than in Group 1. The results indicated a clear increase in tumorigenesis with the higher dose rate and no filtering influence of iron was evident, despite the drop in neutron energy level.
著者
佐伯 誠道 小柳 卓 田中 義一郎 富川 昭男
出版者
日本放射線影響学会
雑誌
Journal of Radiation Research (ISSN:04493060)
巻号頁・発行日
vol.5, no.2, pp.120-123, 1964-06
被引用文献数
1

Mesurements were made on the ^<90>Sr content in human bone samples from subjects who died during the period from 1961 to October 1963 in Japan. The most remarkable accumulation of ^<90>Sr in human bone was found in 0-4 year age group. Considerable increases with time in the S. U. (^<90>Sr pc/g Ca) value was also found in this group.
著者
津郷 友吉 野崎 博 浅利 民弥 山県 登
出版者
日本放射線影響学会
雑誌
Journal of Radiation Research (ISSN:04493060)
巻号頁・発行日
vol.5, no.2, pp.131-137, 1964-06

In succession of the previous report (1), the measurements of strontium-90 (Sr-90), cesium-137 (Cs-137) and iodine-131 (I-131) concentrations in milk were carried out in order to evaluate the range of the radioactive contamination of milk in Japan since 1961. Farm milks collected from various districts of Japan monthly from 1961 to 1963 were used for radioactivity assay. The results of observation show the Sr-90 concentration in milk is higher than that in the previous years (1957-1960) all over the country and there is regional variation in Sr-90 and Cs-137 concentrations.