Template:Aquatic layer topics. An abyssal plain is an underwater plain on the deep ocean floor, usually found at depths between 3000 and 6000 m. Lying generally between the foot of a continental rise and a mid-ocean ridge, abyssal plains cover more than 50% of the Earth âs surface.
Murad discovered in 1977 that nitroglycerin and related artery-widening compounds act by releasing nitric oxide. Furchgott later concluded that cells in the inner lining of blood vessels secrete some unknown substance that makes vessels dilate.
Since the use of nitrous oxide was not based on random assignment, multivariate analyses were performed to assess the effect of nitrous oxide on outcomes after adjusting for a standard set of covariates, determined by IHAST Coordinating Center to be important covariates to include in all post-hoc analyses of neurological and neuropsychological outcomes of the IHAST trial.