Evidence of induction of alloproliferative hyporesponsiveness by opera music. A, Results of cell-proliferation assays in mixed leukocyte cultures (MLCs). The data shown are mean ± SD values. ###P > 0.001 for difference between two groups. B,C,D,E, MLC studies of cytokines. *P > 0.05 and #P > 0.01 for difference between two groups.