animal experiment nonhuman 1,300 controlled study 1,010 article 994 Animals 952 priority journal 858 male 594 mouse 568 animal tissue 552 Male 506 Mice 480 female 480 animal model 472 animal cell 448 Female 418 animal 340 rat 332 protein expression 284 Rats 280 metabolism 250 unclassified drug 244 Article 234 Animalia 214 enzyme activity 210 Animal 170 physiology 170 Humans 168 Mice, Inbred BALB C 160 human 154 Support, Non-U.S. Gov't 152