National Center for Biotechnology Information NCBI NLM MEDLINE RNA humans pubmed abstract nih national institutes of health national library of medicine research support non-u.s. gov't adult female male middle aged Drug Administration Schedule Comparative Study Clinical Trial Randomized Controlled Trial Double-Blind Method Multicenter Study Genotype drug resistance viral / blood drug therapy combination antiviral agents / administration & dosage antiviral agents / therapeutic use* cd4 lymphocyte count microbial / genetics hiv infections / immunology hiv infections / drug therapy* pmid:8656503 c katlama d ingrand h mcdade hiv-1* / drug effects hiv-1* / genetics lamivudine reverse transcriptase inhibitors / administration & dosage reverse transcriptase inhibitors / therapeutic use* zalcitabine / administration & dosage zalcitabine / analogs & derivatives* zalcitabine / therapeutic use zidovudine / administration & dosage zidovudine / therapeutic use*