1. Department of Cell Biology and Human Anatomy, School of Medicine (G.C.D., P.K.), University of California-Davis, Davis California 95616
2. California National Primate Research Center and Department of Obstetrics and Gynecology (C.A.V.), University of California-Davis, Davis California 95616
3. The Wisconsin National Primate Research Center (T.-C.C., T.G.G.), University of Wisconsin-Madison, Madison Wisconsin 53715
4. Departments of Comparative Biosciences, School of Veterinary Medicine, and Obstetrics and Gynecology, School of Medicine and Public Health (T.G.G.), University of Wisconsin-Madison, Madison Wisconsin 53715