Haptoglobin Restores Nitric Oxide-Mediated Vasodilation in Hemoglobin-Exposed Porcine Basilar Arteries Ex Vivo - Hugelshofer, M.; Schaer, C.; Humar, R.; Deuel, J.; Regli, L.; Keller, E.; Schaer, D. (Journal of Neurological Surgery Part A: Central European Neurosurgery, 2018)