The sight of nursing scrubs is a surefire way to get Loki wagging her tail.It’s not something that leaves most dogs panting with excitement. But Loki isn’t your typical dog — she’s a two-year-old Rottweiler therapy dog, or a “dogtor,” as she is otherwise known.Loki and her owner, Caroline Benzel, have been doing therapy sessions at the University of Maryland Medical Center about three times