For these employees, when a holiday falls on a nonworkday -- Saturday or Sunday -- the holiday usually is observed on Monday (if the holiday falls on Sunday) or Friday (if the holiday falls on Saturday).
CK-MB. 1  A creatine kinase-MB (CK-MB) test may be used as a follow-up test to an elevated creatine kinase (CK) in order to determine whether the increase is due to heart damage or skeletal muscle damage.
What is CK? CK is an abbreviation for creatine kinase - also known as CPK - or phosphocreatine kinase. Creatine kinase is a muscle enzyme found in three different types in the human body. In skeletal muscle itâs in the form of CK-MM, in the brain, CK-BB, and in the heart muscle, CK-MB. These forms are known as isoenzymes.