Are the data missing?
Drummond
J C
JC
D000701:Analgesics, Opioid / Q000494:pharmacology*; D000818:Animals; D002560:Cerebrovascular Circulation / Q000187:drug effects*; D004285:Dogs; D005283:Fentanyl / Q000494:pharmacology*; D010101:Oxygen Consumption / Q000187:drug effects; D010880:Piperidines / Q000494:pharmacology*; D000077208:Remifentanil
D000701:Analgesics, Opioid; D010880:Piperidines; D000077208:Remifentanil; D005283:Fentanyl