Hatoko no umi (partially found japanese drama series; 1974-1975)
From The Lost Media Wiki
14th asadora drama that aired from April 7, 1974 (Showa 49) to April 5, 1975 (Showa 50) for a total of 312 episodes it's about a woman who lost her memory after experiencing the atomic bombing of Hiroshima. Of the 312 episodes made there are 40 episodes known exist the first and final episode in there original broadcast format while 38 additional episodes had been recovered from off-air recordings https://www2.nhk.or.jp/archives/tv60bin/detail/index.cgi?das_id=D0009010184_00000