MedStar Health has completed its acquisition of Southern Maryland Hospital Center in Clinton, adding its 10th hospital and important territory in the emerging fight for control of Maryland's health care market. Terms were not disclosed. Concurrent with the transaction, Southern Maryland is ending its run as Maryland's only for-profit hospital. It is now a nonprofit subsidiary of MedStar, which has renamed the hospital MedStar Southern Maryland and pledged to invest at least $100 million over five years to upgrade the campus.