2 0 0 0 OA A. Acute Effects
- 著者
- 大北 威
- 出版者
- Journal of Radiation Research Editorial Committee
- 雑誌
- Journal of Radiation Research (ISSN:04493060)
- 巻号頁・発行日
- vol.16, no.SUPPLEMENT, pp.49-66, 1975-09-16 (Released:2006-07-14)
- 参考文献数
- 132
- 被引用文献数
- 26
An outline of the acute effects of the Hiroshima and Nagasaki atomic bombs are summarized, based on documentary records. Acute injuries caused by the atomic bombs have been classified as thermal, mechanical, and radiation injuries. Combinations of these were most common. Many died from the immediate effects of blast and burns, but individuals often succumbed to trauma or burns before the radiation syndrome developed. Many more would have died from irradiation, had they been saved from the effects of trauma or burns. Nearly all who died within 10 weeks had signs suggestive of radiation injuries. Remarkable variation in sensitivity of body tissues to ionizing radiation was apparent. Radiation-induced bone marrow depletion was the most critical damage leading to death. In these instances, leukopenia and thrombocytopenia, and subsequent infections and hemorrhagic tendencies were the main causes of death. The clinical symptoms and signs of radiation injuries; the RBE of the atomic bomb neutrons for acute effects; and the effects of irradiation on spermatogenesis are also discussed.
- 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.
人為的な環境変化,とくに温室効果ガスによる気候温暖化と放射能汚染とに焦点をしぼって,気候変化と自然植生・作物生産および原爆・原子炉事故による放射能汚染の広がりを3年間わたって研究した。その結果は次のように要約できる。1.水田水温環境への気候温暖化の影響は顕著で,現在より2〜4℃高まり、安全移植期は2週間早まることが分かった。水温上昇により水面蒸発は気温上昇あたり3〜6%増加し,温暖化気候下(2100年頃)では10%以上蒸発が増大する可能性がある。2.作物収量へのCO_2直接効果と気候温暖化の影響を評価するため,作物モデルと気候シナリオを利用した。イネは現行農法下では減収となるが、早生品種導入を試みると増収が予想され,増収率は北日本で大きくなった。トウモロコシ・コムギは降水変動の影響が大で,灌がいを施すと増収する。3.植生分布へのCO_2気候温暖化のインパクトを評価し,低温地帯の植物種に好適な気候域の急減することが分かった。暖地系植物にとっての好適気候域は4〜6km/年の速度で北上すると予想された。この移動速度は花粉分析からの植物移動速度の5〜10倍で,温暖化による植生分布の混乱が予想される。4.原子爆弾・原子炉事故による放射能汚染域の推定に拡散研究用数値シミュレ-ションモデルを用いた。広島・長崎原爆による汚染評価に,熱対流雲モデルを用いて,1kmメッシュ上での微粒子落下,ショック麈,火災煙からの被曝量を個別に評価した。最大の被曝総量は12時間後に,13R/hrとなった。チェルヴィリ原子炉事故による放射能広域拡散の研究に,広域拡散モデルを用いて,その有効性を確認した。