controlled study nonhuman 370 article 301 unclassified drug 185 priority journal 131 plant extract 95 plant leaf 87 Animals 84 Article 76 metabolism 68 Argentina 66 animal cell 66 genetics 60 antiviral activity 51 Plant Extracts 50 chemistry 49 mouse 49 human 47 Humans 45 enzyme activity 45 animal experiment 44 Plant Leaves 43 in vitro study 41 Plant Proteins 40 human cell 36 Plants (botany) 35 drug isolation 34 plant 34 plant root 34 protein expression 34