1. Istituto di Clinica Medica Generale e Terapia Medica, Universita' degli Studi di Parma, Parma, Italy
2. Istituto di Clinica Ostetrica e Ginecologica, Universita' degli Studi di Parma, Parma, Italy
3. Department of Pathology, University of Edinburgh, Medical School, Edinburgh, U.K.
4. Department of Human Metabolism and Clinical Biochemistry, Medical School, University of Sheffield, Sheffield, U.K.