1. Biocenter Oulu and World Health Organization Collaborating Centre for Research on Reproductive Health (T.J.P., R.M.K., M.H.P., P.V.I., J.P.J.M., R.K.V., P.T.V.), University of Oulu, FIN-90220 Oulu, Finland
2. the Department of Anatomy (J.T.L.), University of Oulu, FIN-90220 Oulu, Finland
3. the Hauptman-Woodward Medical Research Institute, Inc., and Roswell Park Cancer Institute (D.G.), Buffalo, New York 14203
4. the Department of Biosciences, Division of Biochemistry (P.T.V.), FIN-00014 University of Helsinki, Finland