ACVRL1/TNFRSF19 protein level ratio in blood (Ontology of Biological Attributes entry OBA_2055779) can be described as follows. A compound attribute that is the ratio of amount of activin receptor type-1-like (human) in blood to amount of tumor necrosis factor receptor superfamily member 19 (human) in blood. Also known as: the ratio of amount of activin receptor type-1-like (human) in blood to amount of tumor necrosis factor receptor superfamily member 19 (human) in blood.