[1] UNIV ARKANSAS MED SCI HOSP, DEPT OBSTET & GYNECOL, LITTLE ROCK, AR 72205 USA
[2] UNIV ARKANSAS MED SCI HOSP, DEPT MICROBIOL & IMMUNOL, LITTLE ROCK, AR 72205 USA
[3] UNIV FLORIDA, DEPT LAB MED & PATHOL, DIAGNOST REFERRAL LABS, GAINESVILLE, FL 32610 USA