Fibroblast-conditioned medium significantly affects the morphological and functional differentiation of human epidermal melanocytes,but much less of human melanoma cells(正常ヒト表皮メラノサイト(NHEM)とヒト黒色腫細胞株SK-MEL23の細胞増殖と分化に対する線維芽細胞培養液上清(FCM)の影響)