DNA replication is one of the most basic processes that occurs within a cell. Each time a cell divides, the two resulting daughter cells must contain exactly the same genetic information, or DNA, as the parent cell.
Radial nerve palsy. Radial nerve palsy in the arm most commonly is caused by fracture of the humerus, especially in the middle third (Holstein-Lewis fracture) or at the junction of the middle and distal thirds. The nerve may be compressed by the lateral intermuscular septum.
1 A disorder affecting the brain, such as an aneurysm or brain tumor, may also cause third nerve palsy. Diabetes and migraines are other possible causes.  Fourth nerve palsy is often a congenital birth defect, which means that a baby is born with it. But a head injury, stroke, or tumor can also cause fourth nerve palsy.