Medisys Health Network, Inc. | 8,937 followers on LinkedIn. The MediSys Health Network, based in Queens New York, includes Jamaica Hospital Medical Center, Flushing Hospital Medical Center, Jamaica Hospital Nursing Home, The Advanced Center for Psychotherapy, and a network of community-based ambulatory care centers and private physician practices known respectively as the MediSys Ambulatory Care Network and TJH Medical, offer a wide range of comprehensive, high-quality inpatient and outpatient services to the people of Queens and South-East Brooklyn.