{"created":"2023-05-15T14:50:06.796436+00:00","id":68536,"links":{},"metadata":{"_buckets":{"deposit":"862161ae-1d67-4c27-a5c5-96ed92d808ab"},"_deposit":{"created_by":1,"id":"68536","owners":[1],"pid":{"revision_id":0,"type":"depid","value":"68536"},"status":"published"},"_oai":{"id":"oai:repo.qst.go.jp:00068536","sets":["10:28"]},"author_link":["672652","672647","672651","672642","672648","672645","672646","672644","672650","672649","672643","672641"],"item_10005_date_7":{"attribute_name":"発表年月日","attribute_value_mlt":[{"subitem_date_issued_datetime":"2005-11-17","subitem_date_issued_type":"Issued"}]},"item_10005_description_5":{"attribute_name":"抄録","attribute_value_mlt":[{"subitem_description":"[Objective] Epidemiology on A-bomb survivors has clarified that childhood exposure confers high breast cancer risk. But the underlying mechanism is unclear. Using Sprague-Dawley rats, we attempted to verify if childhood exposure (1) results in increased development of mammary cancer and (2) affects susceptibility to a subsequent carcinogen. <br>\n[Methods] Rats were (1) &gamma;-irradiated (2 Gy) or treated with methylnitrosourea (MNU; 20 mg/kg, i.p.) at 3 or 7 weeks (w) of age; or (2) irradiated at 3 w and then MNU-treated at either 3 or 7 w. They were observed until 50 w. <br>\n[Results] (1) Spontaneous palpable mammary cancer multiplicity was 0.07 &plusmn; 0.04 (tumors/rat, mean &plusmn; SEM). Rats irradiated at 3 w developed significantly less tumors than those irradiated at 7 w (0.28 &plusmn; 0.11 vs. 0.90 &plusmn; 0.24, respectively). (2) Contrarily, rats treated with MNU at 3 w developed significantly more tumors than those treated at 7 w (0.56 &plusmn; 0.20 vs. 0.11 &plusmn; 0.08, respectively). After irradiation at 3 w, MNU treatment at 3 w resulted in an additive effect (0.76 &plusmn; 0.20), while treatment at 7 w elicited a synergistic effect (0.71 &plusmn; 0.18). <br>\n[Discussion] Relatively low susceptibility to mammary cancers after prepubertal exposure in rats contradicts with epidemiologic data on A-bomb survivors. However, our data suggest that childhood exposure deposits a long-term effect that becomes apparent in combination with subsequent carcinogen exposure. The nature of this long-term effect remains to be elucidated.","subitem_description_type":"Abstract"}]},"item_10005_description_6":{"attribute_name":"会議概要（会議名, 開催地, 会期, 主催者等）","attribute_value_mlt":[{"subitem_description":"第48回日本放射線影響学会／第1回アジア放射線研究会議","subitem_description_type":"Other"}]},"item_access_right":{"attribute_name":"アクセス権","attribute_value_mlt":[{"subitem_access_right":"metadata only access","subitem_access_right_uri":"http://purl.org/coar/access_right/c_14cb"}]},"item_creator":{"attribute_name":"著者","attribute_type":"creator","attribute_value_mlt":[{"creatorNames":[{"creatorName":"Imaoka, Tatsuhiko"}],"nameIdentifiers":[{"nameIdentifier":"672641","nameIdentifierScheme":"WEKO"}]},{"creatorNames":[{"creatorName":"Nishimura, Mayumi"}],"nameIdentifiers":[{"nameIdentifier":"672642","nameIdentifierScheme":"WEKO"}]},{"creatorNames":[{"creatorName":"Kakinuma, Shizuko"}],"nameIdentifiers":[{"nameIdentifier":"672643","nameIdentifierScheme":"WEKO"}]},{"creatorNames":[{"creatorName":"Ohmachi, Yasushi"}],"nameIdentifiers":[{"nameIdentifier":"672644","nameIdentifierScheme":"WEKO"}]},{"creatorNames":[{"creatorName":"Nishimura, Yukiko"}],"nameIdentifiers":[{"nameIdentifier":"672645","nameIdentifierScheme":"WEKO"}]},{"creatorNames":[{"creatorName":"Shimada, Yoshiya"}],"nameIdentifiers":[{"nameIdentifier":"672646","nameIdentifierScheme":"WEKO"}]},{"creatorNames":[{"creatorName":"今岡 達彦","creatorNameLang":"en"}],"nameIdentifiers":[{"nameIdentifier":"672647","nameIdentifierScheme":"WEKO"}]},{"creatorNames":[{"creatorName":"西村 まゆみ","creatorNameLang":"en"}],"nameIdentifiers":[{"nameIdentifier":"672648","nameIdentifierScheme":"WEKO"}]},{"creatorNames":[{"creatorName":"柿沼 志津子","creatorNameLang":"en"}],"nameIdentifiers":[{"nameIdentifier":"672649","nameIdentifierScheme":"WEKO"}]},{"creatorNames":[{"creatorName":"大町 康","creatorNameLang":"en"}],"nameIdentifiers":[{"nameIdentifier":"672650","nameIdentifierScheme":"WEKO"}]},{"creatorNames":[{"creatorName":"西村 由希子","creatorNameLang":"en"}],"nameIdentifiers":[{"nameIdentifier":"672651","nameIdentifierScheme":"WEKO"}]},{"creatorNames":[{"creatorName":"島田 義也","creatorNameLang":"en"}],"nameIdentifiers":[{"nameIdentifier":"672652","nameIdentifierScheme":"WEKO"}]}]},"item_language":{"attribute_name":"言語","attribute_value_mlt":[{"subitem_language":"eng"}]},"item_resource_type":{"attribute_name":"資源タイプ","attribute_value_mlt":[{"resourcetype":"conference object","resourceuri":"http://purl.org/coar/resource_type/c_c94f"}]},"item_title":"Mammary carcinogenesis after prepubertal radiation exposure in rats: effect of age at exposure to gamma-rays, 1-methyl-1-nitrosourea and their combination","item_titles":{"attribute_name":"タイトル","attribute_value_mlt":[{"subitem_title":"Mammary carcinogenesis after prepubertal radiation exposure in rats: effect of age at exposure to gamma-rays, 1-methyl-1-nitrosourea and their combination"}]},"item_type_id":"10005","owner":"1","path":["28"],"pubdate":{"attribute_name":"公開日","attribute_value":"2006-06-26"},"publish_date":"2006-06-26","publish_status":"0","recid":"68536","relation_version_is_last":true,"title":["Mammary carcinogenesis after prepubertal radiation exposure in rats: effect of age at exposure to gamma-rays, 1-methyl-1-nitrosourea and their combination"],"weko_creator_id":"1","weko_shared_id":-1},"updated":"2023-05-15T20:25:03.089411+00:00"}