[1] Virginia Commonwealth Univ, Richmond, VA 23284 USA
[2] McGuire VA Med Ctr, Richmond, VA 23284 USA
[3] Univ Alberta, Edmonton, AB, Canada
[4] Dallas VA Med Ctr, Dallas, TX USA
[5] Baylor Univ, Med Ctr, Dallas, TX USA
[6] Univ Toronto, Toronto, ON, Canada
[7] Univ Washington, Seattle, WA 98195 USA
[8] Univ Denver, Denver, CO USA
[9] Yale Univ, Med Ctr, West Haven, CT USA
[10] Mayo Clin, Rochester, MN USA
[11] Univ Tennessee, Memphis, TN USA
[12] Univ Rochester, Rochester, NY USA
[13] Univ Arizona, Phoenix, AZ USA
[14] Univ Texas Houston, Houston, TX USA
[15] Univ Calif San Francisco, San Francisco, CA 94143 USA
[16] Mercy Med Ctr, Baltimore, MD USA
[17] Mayo Clin, Scottsdale, AZ USA
[18] Emory Univ, Med Ctr, Atlanta, GA 30322 USA
[19] Univ Penn, Philadelphia, PA 19104 USA