Section 18. Any medical service corporation may contract with any person for the purpose of providing administrative or other services relating to the providing of medical or other health services or reimbursement therefor. In addition, with the approval of the commissioner who shall consider the effect upon subscriber agreements and subscriber rates, a medical service corporation may, after being authorized by its board of directors, or by a committee thereof, charged with the duty of authorizing transactions under this section, make loans to, guarantee loans of and make investments in hospitals and providers of other health services for the purpose of improving efficiency, reducing costs, or increasing benefits in the delivery of health services to subscribers and others.