Tadalafil treatment for fetuses with early-onset growth restriction: a protocol for a multicentre, randomised, placebo-controlled, double-blind phase II trial (TADAFER IIb) oleh Hiroaki Tanaka, Yasuhiro Tanaka, Yoichi Aoki, Masayuki Endo, Tomoaki Ikeda, Shintaro Maki, Masafumi Nii, Kayo Tanaka, Satoshi Tamaru, Toru Ogura, Yuki Nishimura, Tomomi Kotani, Akihiko Sekizawa, Masahiko Nakata, Koji Nakamura, Kenji Nagao, Ichiro Yasuhi, Hiroshi Kawamura, Sho Takakura, Mayumi Kotera, Takafumi Ushida, Norihiko Kikuchi, Tadatsugu Kinjo, Mayumi Takano, Sachie Suga, Michi Kasai, Osamu Yasui, Yuka Maegawa, Shigeru Aoki, Yoshio Yoshida