1. O23.1 Sexual Risk Trajectories Among MSM in the United States: Implications For PrEP Delivery. (13th July 2013) Authors: Pines, H A; Gorbach, P M; Weiss, R E; Shoptaw, S; Ostrow, D G; Stall, R D; Plankey, M Journal: Sexually transmitted infections Issue: Volume 89(2013)Supplement 1 Page Start: A71 Record Type: Journal Article View Content: Available online (eLD content is only available in our Reading Rooms) ↗