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[2] UNIV PENN, SCH MED, HEMATOL ONCOL SECT, PHILADELPHIA, PA 19104 USA
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[4] AUDIE L MURPHY MEM VET HOSP, INFECT DIS SECT, SAN ANTONIO, TX 78284 USA
[5] UNIV TEXAS, HLTH SCI CTR, DEPT MED, SAN ANTONIO, TX 78284 USA