[1] VET ADM MED CTR, CTR PULM DIS, SYRACUSE, NY 13210 USA
[2] JOHNS HOPKINS UNIV, BALTIMORE, MD 21218 USA
[3] FRANCIS SCOTT KEY MED CTR, DIV PULM MED, BALTIMORE, MD USA
[4] FRANCIS SCOTT KEY MED CTR, CHEST CLIN, BALTIMORE, MD USA
[5] NORTHWESTERN UNIV, SCH MED, CHICAGO, IL 60611 USA
[6] SANTA CLARA VALLEY MED CTR, SAN JOSE, CA 95128 USA
[7] NEW YORK MED COLL, WESTCHESTER CTY MED CTR, VALHALLA, NY 10595 USA
[8] EMORY UNIV, GRADY MEM HOSP, DIV PULM, ATLANTA, GA 30322 USA
[9] VET ADM HOSP, DEPT MED, HINES, IL 60141 USA
[10] YALE UNIV, SCH MED, NEW HAVEN, CT 06510 USA
[11] DANBURY HOSP, DEPT RESP THERAPY, DANBURY, CT 06810 USA
[12] VET ADM MED CTR, SEATTLE, WA 98108 USA
[13] NEW YORK MED COLL, VALHALLA, NY 10595 USA
[14] WESTCHESTER CTY MED CTR, PULM DIS SECT, VALHALLA, NY 10595 USA
[15] EMORY UNIV, SCH MED, EMORY CLIN, ATLANTA, GA 30322 USA
[16] UNIV UTAH, MED CTR, DIV RESP CRIT CARE & OCCUPAT MED, SALT LAKE CITY, UT 84112 USA
[17] UNIV MIAMI, SCH MED, MIAMI, FL 33152 USA
[18] MT SINAI MED CTR, MIAMI BEACH, FL 33140 USA
[19] VET ADM HOSP, DEPT RESP CARE, HINES, IL 60141 USA
[20] MT SINAI MED CTR, DIV PULM, MIAMI BEACH, FL 33140 USA