(b) Every hospital or other health agency in this state meeting the standards prescribed by the board of directors of each such corporation shall be eligible for participation in any hospital service plan, or health service plan, operating in this state. Every duly licensed physician, duly licensed dentist, duly licensed chiropodist-podiatrist, duly licensed chiropractor or other health agency in this state meeting the standards prescribed by the board of directors of each such corporation shall be eligible for participation in any medical service plan, or health service plan, operating in this state. Every duly licensed dentist or duly licensed physician in this state meeting the standards prescribed by the board of directors of each such corporation shall be eligible for participation in any dental service plan, or health service plan, operating in this state. The board of directors of every such corporation may also prescribe standards for hospitals, physicians, dentists, chiropodists- podiatrists, chiropractors and other health agencies located in states adjoining this state, and all such hospitals, physicians, dentists, chiropodists-podiatrists, chiropractors and other health agencies meeting such standards shall be eligible for participation in such plans.