Medical information exchange and integration is the effective method to solve the interoperability and medical information island, and is the basis of medical information sharing. In this paper, we take medical texts and medical images as the basic integrated objects, DICOM, HL7 messages and datasets as the integrated units, efficient DI-COM, HL7 message construction and parsing methods as basis, design and realize a universal medical information integration and exchange service middleware. Experimental results show that the prototype system could perform medical information integration and exchange among relational database, HL7 and DICOM message, provide a feasible scheme to solve the medical information island and lay a good foundation for establishing the unified medical information integration and sharing platform. The middleware has been applied in the project named "development and demonstration of opened medical information integration system".