Alteplase at 0.6 mg/kg for acute ischemic stroke within 3 hours of onset: Japan Alteplase Clinical Trial (J-ACT). National Cardiovascular Center, Suita, Osaka, Japan. tyamaguc@hsp.ncvc.go.jp BACKGROUND AND PURPOSE: Based on previous studies comparing different recombinant tissue plasminogen activator (rt-PA) doses, we performed a clinical trial with 0.6 mg/kg, which is lower than the international