1. Release of histamine from skin and muscle in the cat by opium alkaloids and other histamine liberators;Feldberg;J. Physiol.,1951
2. Morphine as an inhibitor of brain cholinesterases in morphine tolerant and non-tolerant rats;Jóhannesson;Acta pharmacol. et toxicol.,1962
3. The analgetic activity and brain concentration of morphine in tolerant and non-tolerant rats given morphine alone or in combination with neostigmine;Jóhannesson;Acta pharmacol. et toxicol.,1963a
4. Morphine and normorphine in the brain of rats given identically algaesic doses of morphine, codeine or normorphine;Jóhannesson;Acta pharmacol. et toxicol.,1963b