1. University of California, Davis, Sacramento Medical Center, Sacramento, California 95817
2. University Hospital, Seattle, Washington 98195
3. Medical College of Virginia, Virginia Commonwealth University, Richmond, Virginia 23298
4. University of Washington, Seattle, Washington 98195
5. Center for Disease Control, Atlanta, Georgia 30333
6. Mayo Clinic and Mayo Foundation, Rochester, Minnesota 55901
7. Lilly Laboratory for Clinical Research, Marion County General Hospital, Indianapolis, Indiana 46202