1. Division of Infectious Diseases, Department of Veterans Affairs, Boise, Idaho
2. Medical Service, Miami Veterans Affairs Health Care System, Florida
3. San Francisco General Hospital, University of California
4. Division of General Surgery, University of Washington, Seattle
5. University of California, Los Angeles, School of Medicine, and R. M. Alden Research Laboratory, Santa Monica, California
6. Department of Community Health, Tufts University, Boston, Massachusetts
7. Medical Service, Puget Sound Veterans Affairs Medical Center, Seattle, Washington
8. Department of Pediatrics, Baylor College of Medicine, Houston, Texas
9. Department of Medicine, Stanford University, California
10. Geisinger Health System, Geisinger Cancer Institute, Danville, Pennsylvania