Estimating trends in the proportion of transmitted and acquired HIV drug resistance in a long term observational cohort in Germany. oleh Daniel Schmidt, Christian Kollan, Gerd Fätkenheuer, Eugen Schülter, Hans-Jürgen Stellbrink, Christian Noah, Björn-Erik Ole Jensen, Matthias Stoll, Johannes R Bogner, Josef Eberle, Karolin Meixenberger, Claudia Kücherer, Osamah Hamouda, Barbara Bartmeyer, ClinSurv-HIV Drug Resistance Study Group in CHAIN