Low expression of the cell cycle inhibitor p27Kip1 in normal corticotroph cells, corticotroph tumors, and malignant pituitary tumors - Lidhar, K; Korbonits, M; Jordan, S; Khalimova, Z; Kaltsas, G; Lu, X; Clayton, R N; Jenkins, P J; Monson, J P; Besser, G M; Lowe, D G; Grossman, A B (J Clin Endocrinol Metab, 1999)