[1] Univ Texas Southwestern Med Ctr Dallas, Dept Emergency Med, 5323 Harry Hines Blvd, Dallas, TX 75390 USA
[2] Univ Texas Southwestern Med Ctr, Sch Med, Dallas, TX USA
[3] Univ Texas Southwestern Med Ctr, Dept Immunol, Dallas, TX USA
[4] Univ Texas Southwestern Med Ctr, Dept Family Med, Dallas, TX USA