いっかん　（Ｉｋｋａｎ） ぶん？こうせいじょう(Bun/Kousei-jyou) as this read so

一貫　(begin to end /Thorough) 文・構成上(reason of sentance structure/circumstance of sentence structure) Japanese　original might be 文の構成上 or drop off some word.