TY  - JOUR 
T1  - Markers, Cofactors and Staging Systems in the Study of HIV Disease Progression: A Review
JO  - Memórias do Instituto Oswaldo Cruz
A1  - Portela, MC
A1  - Simpson, KN
SN  - 0074-0276
UL  - 10.1590/S0074-02761997000400001
VL  - 92 
Y1  - 1997
PB  - Brazil 
ER  -