title: Reminiscences of early studies of placental function (Louis B. Flexner).
mesh_terms: D000818:Animals; D004219:District of Columbia; D005260:Female; D049673:History, 20th Century; D008396:Maryland; D008431:Maternal-Fetal Exchange; D009774:Obstetrics / Q000266:history*; D011247:Pregnancy; D012975:Sodium Isotopes
chemical_list: D012975:Sodium Isotopes