National Center for Biotechnology Information NCBI NLM MEDLINE humans pubmed abstract nih national institutes of health national library of medicine prognosis research support u.s. gov't male P.H.S. Antigens follow-up studies Cohort Studies Proportional Hazards Models multicenter studies as topic leukocyte count hiv infections / immunology* t-lymphocyte subsets / immunology* cd4-positive t-lymphocytes / immunology acquired immunodeficiency syndrome / immunology differentiation t-lymphocyte / analysis cd / analysis adp-ribosyl cyclase adp-ribosyl cyclase 1 cd57 antigens membrane glycoproteins pmid:7686224 j v giorgi z liu r detels acquired immunodeficiency syndrome / etiology* differentiation / analysis* cd8 antigens / analysis* cell adhesion molecules / analysis hla-dr antigens / analysis l-selectin