All participants will receive ReoPro. Some will also receive Retavase, which may boost the effectiveness of ReoPro. Retavase is administered in a single dose through a needle in the vein over 2 minutes. ReoPro is infused into the vein over 12 hours. Patients will be monitored with physical examinations, blood tests, computed tomography (CT) scans, and three or four MRI scans of the brain to evaluate both the response to treatment and side effects of the drugs. An MRI scan will be done 24 hours, 5 days and 30 days after starting the study medication, and possibly during screening for this study.