Real-life clinical cases for the basic sciences and the USMLE Step 1§The Case Files series is an award-winning learning system proven to improve exam scores. This series helps you to learn in the context of real patients instead of simply memorizing. Case Files: Biochemistry: Third Edition presents 50 clinical cases with open-ended questions which weave basic science concepts into the clinical scenario. Each case includes an extended discussion (including definitions and a pathophysiology discussion), key points, and 3-5 USMLE-style comprehension questions. §