Dephosphorylates the 5' and 2'(3')-phosphates of deoxyribonucleotides and has a broad substrate specificity. Helps to regulate adenosine levels in heart during ischemia and hypoxia. a ribonucleoside 5'-phosphate + H2O = a ribonucleoside + phosphate Activated by ADP. Highly expressed in skeletal muscle. Detected at intermediate levels in heart, brain, kidney and pancreas. Belongs to the 5'-nucleotidase type 3 family.