Antinociceptive activity and toxicological study of aqueous extract of Egletes viscosa Less (Asteraceae) - Araújo, A AS; Bonjardim, L R; Mota, É M; Albuquerque-Júnior, R LC; Estevam, C S; Cordeiro, L; Seixas, S RS; Batista, J S; Quintans-Júnior, L J (Braz J Pharm Sci, 2008)