Algorithms|Amino Acid Substitution|Anti-HIV Agents|Databases, Genetic|Databases, Protein|Drug Resistance, Viral|HIV|HIV Protease|HIV Protease Inhibitors|Indinavir|Information Storage and Retrieval|Models, Biological|Models, Molecular|Mutation|Neural Networks (Computer)|Protein Binding|Protein Conformation|Saquinavir|Sequence Analysis, Protein|Structure-Activity Relationship