group 7 element
http://purl.jp/bio/4/id/200906074148809771
http://purl.jp/bio/4/id/200906059978835989
http://jglobal.jst.go.jp/en/detail?JGLOBAL_ID=200906074148809771
http://purl.jp/bio/4/subject/CA03
http://purl.jp/bio/4/id/200906093773434730