Observation on the fine structure of the sheep placenta.
D000818:Animals; D004717:Endometrium / Q000166:cytology; D004847:Epithelial Cells; D005321:Extraembryonic Membranes / Q000166:cytology*; D005260:Female; D006651:Histocytochemistry; D008431:Maternal-Fetal Exchange; D008854:Microscopy, Electron; D010920:Placenta / Q000166:cytology*; D011247:Pregnancy; D011270:Pregnancy, Animal; D012756:Sheep