Evaluate the effectiveness of Yangxue Qingnao Granules in preventing post thrombolytic hemorrhage transformation in patients with acute cerebral infarction, and explore its possible mechanism

Inclusion Criteria:

• Age ≥ 50 years old, regardless of gender
• After the onset of this disease, the National Institutes of Research Stroke Scale score was 2 ≤ NIHSS ≤ 20 points
• Patients who have developed symptoms within 4.5 hours and can receive rt PA intravenous thrombolysis treatment
• According to the 2019 Diagnosis Points for Major Cerebrovascular Diseases in China, patients with ischemic stroke were diagnosed as having a good recovery from the first or last onset (mRS score ≤ 1 point before this onset)
• Obtain the patient or their legal representative to voluntarily sign an informed consent form approved by the ethics committee.

Exclusion Criteria:

• Intracranial hemorrhagic diseases seen on cranial imaging: hemorrhagic stroke, epidural hematoma, intracranial hematoma, ventricular hemorrhage, subarachnoid hemorrhage, etc; If it is only oozing blood, the researcher can determine whether it is suitable for enrollment
• Severe consciousness disorder: NIHSS scored>1 point in the 1a consciousness level item
• After controlling the patient's blood pressure, the systolic blood pressure remains ≥ 180mmHg or the diastolic blood pressure remains ≥ 100mmHg
• Blood glucose<2.8mmol/L (random blood glucose measurement device can be used)
• Patients with severe mental disorders and dementia
• Diagnosed with severe active liver diseases, such as acute hepatitis, chronic active hepatitis, cirrhosis, etc; Or ALT or AST>2.0 x ULN
• Diagnosed with severe active kidney disease and renal insufficiency; Or serum creatinine>1.5 × ULN
• Concurrent malignant tumors or ongoing anti-tumor treatment; For subjects diagnosed with malignant tumors after enrollment, the decision to continue participating in the study can be based on the researcher's judgment and the subject's willingness
• Suffering from severe systemic diseases, with an estimated survival time of<90 days
• History of major surgery within 4 weeks prior to enrollment
• Participated in other clinical studies within the first 30 days of randomization, or is currently participating in other clinical studies
• The researcher believes that it is not suitable to participate in this clinical study
• Patients who are allergic to any ingredient in the study drug