[Studies on cardiac ingredients of plants: biological activities and structural variation of xanthines].
D000818:Animals; D006168:Guinea Pigs; D006339:Heart Rate / Q000187:drug effects; D066298:In Vitro Techniques; D008297:Male; D009119:Muscle Contraction / Q000187:drug effects; D009200:Myocardial Contraction / Q000187:drug effects; D010726:Phosphodiesterase Inhibitors; D013329:Structure-Activity Relationship; D014970:Xanthines / Q000138:chemical synthesis / Q000494:pharmacology*
D010726:Phosphodiesterase Inhibitors; D014970:Xanthines