Animals 2,999 nonhuman 2,814 article 2,726 priority journal 1,843 controlled study 1,752 animal 1,706 animal experiment 1,326 animal cell 1,124 Male 1,066 male 1,050 Female 1,013 female 971 rat 851 mouse 810 animal tissue 774 Mice 748 Rats 738 metabolism 730 Humans 713 human 705 Animal 697 unclassified drug 689 physiology 677 Animalia 521 Support, Non-U.S. Gov't 478 Argentina 476 Article 476 animal model 475 protein expression 453 genetics 403