Influence of menstrual cycle on NK activity - Souza, Saulo Soares de; Castro, Fabíola Attié de; Mendonca, Heliodora Carneiro de; Palma, Patricia Vianna Bonini; Morais, F. R.; Ferriani, Rui Alberto; Voltarelli, Júlio César (Journal of Reprodutive Immunology, 2001)