ABSTRACT
Data were collected from 1614 homosexual and bisexual men in 1984 through 1985 and from 1988 to 1992 in Pittsburgh. Of the men entering the study since 1988, 16% reported engaging in unprotected anal receptive intercourse with more than one partner during the 6 months before their visit. Approximately 7% of the younger men and 18% of the men over 22 years of age in the recent cohort were already infected with the human immunodeficiency virus, the same rates as those described 8 years ago. Aggressive risk-reduction programs are needed in high schools and existing networks in the gay community.
Subject(s)
Bisexuality/psychology , HIV Infections/epidemiology , HIV-1 , Homosexuality/psychology , Sexual Behavior , Adolescent , Adult , Age Factors , Alcohol Drinking/epidemiology , Bisexuality/statistics & numerical data , Comorbidity , Condoms/statistics & numerical data , Employment/statistics & numerical data , Follow-Up Studies , HIV Infections/prevention & control , Homosexuality/statistics & numerical data , Humans , Male , Pennsylvania/epidemiology , Racial Groups , Sexually Transmitted Diseases/complications , Sexually Transmitted Diseases/epidemiology , Surveys and Questionnaires , Urban PopulationABSTRACT
The isolation of milligram amounts of the enantiomers of a benzodiazepinone derivative was performed on an analytical cellulose tribenzoate-based column by multiple repetitive injections. An enantiomeric purity greater than 98% was required. First, an analytical method was developed to maximize the resolution by adjusting the mobile phase composition, flow-rate and most importantly the column temperature. Then the preparative separation was optimized by adjusting the sample size and detecting the sample where its UV absorbance was low. The locations of the cut points were determined by use of detector response levels. The method development, preparative separations and analytical assays of the fractions obtained were all performed on analytical columns.
