[1] UNIV BOLOGNA,IST MICROSCOPIA ELETTR CLIN,I-40126 BOLOGNA,ITALY
[2] OSPED S ANNA,DIV REUMATOL,FERRARA,ITALY
[3] UNIV FERRARA,DERMATOL CLIN,I-44100 FERRARA,ITALY
[4] UNIV MILAN,CATTEDRA ANAT PATOL 4,I-20133 MILAN,ITALY
[5] UNIV PADUA,IST ISTOL & EMBRIOL GEN,I-35100 PADUA,ITALY