animal experiment controlled study nonhuman 129 protein expression rat Animals 112 article 105 Rats 102 priority journal 99 animal tissue 95 Rats, Sprague-Dawley 72 female 66 animal model 61 animal cell 59 male 59 Female 56 Male 51 Western blotting 38 unclassified drug 36 immunohistochemistry 33 messenger RNA 33 progesterone 32 animal 31 apoptosis 31 Ovary 30 RNA, Messenger 27 Rats, Wistar 26 Apoptosis 25 Rattus 25 metabolism 25