• Drug: Alteplase
  According to 0.6-0.9mg / kg alteplase (maximum can not exceed 90mg), of which 10% intravenous injection, the remaining 60 minutes intravenous infusion.
• Drug: Urokinase
  1.2-1.5 million U dissolved in 100ml sodium chloride injection, 30 minutes intravenously.

• Alteplase group
  According to 0.6-0.9mg / kg alteplase (maximum can not exceed 90mg), of which 10% intravenous injection, the remaining 60 minutes intravenous infusion
  Intervention: Drug: Alteplase
• Urokinase group
  1.2-1.5 million U dissolved in 100ml sodium chloride injection, 30 minutes intravenously End
  Intervention: Drug: Urokinase

Inclusion Criteria:

• 1) age> 18 years old;
• 2) meet the diagnostic criteria of China 2014 guidelines for the diagnosis and treatment of acute ischemic stroke;
• 3) no history of first sepsis or previous cerebral infarction sequelae (mRS ≤ 1);
• 4) within 3 hours of onset;
• 5) Have measurable neurological deficits;
• 6) Patients or legal guardians can understand and sign informed consent.

Exclusion Criteria:

• Absolute exclusion criteria:
• 1) history of head trauma or stroke within the last 3 months;
• 2) suspected subarachnoid hemorrhage;
• 3) history of previous intracranial hemorrhage;
• 4) intracranial tumor, arteriovenous malformation or aneurysm ;
• 5) recent intracranial or intraspinal surgery;
• 6) arterial puncture at an incurable site within the last 7 days;
• 7) elevated blood pressure: systolic blood pressure ≥180 mm Hg, or diastolic blood pressure ≥100 mm Hg;
• 8) Internal bleeding;
• 9) acute bleeding tendency, including platelet count less than 100 × 109 / L or other conditions;
• 10) heparin treatment within 48 h (APTT is outside the upper limit of normal range);
• 11) oral anticoagulant, INR> 1.7 Or PT> 15S;
• 12) are currently using thrombin inhibitors or factor Xa inhibitors, various sensitive laboratory abnormalities (such as APTT, INR, platelet count, ECT; TT or appropriate factor Xa activity assays) ;
• 13) Blood glucose <50 mg / dl (2.7 mmol / L);
• 14) CT suggestive of multiple cerebral infarction (low density range> 1/3 of the cerebral hemispheres) ;
• 15) Other conditions considered unsuitable for inclusion in this clinical study;
• 16) 3 months or are participating in other clinical trials;
• 17) combined with severe systemic disease is expected to survive less than three months.
• Relative exclusion criteria:
• 1) severe stroke (NIHSS> 25 points);
• 2) pregnancy;
• 3) neurological deficits after epileptic seizures;
• 4) major surgery or severe trauma within the last 14 days;
• 5) Urethral hemorrhage;
• 6) Myocardial infarction within the last 3 months;