40 participants will be selected based on eligibility criteria and collected information, then, randomly separated into two groups. All participants will sign informed consent form, monitor vital signs, laboratory examination (CT/MRI, blood routine examination, urine routine examination, liver function, renal function, etc.), NIHSS, Fugl-Meyer analysis (FMA) 0-3 days before treatment. All of them will receive basic treatment with Aspirin Enteric-coated Tablets and Atorvastatin Calcium. And experimental group will treat with hUC-MSC, control group with placebo (normal saline) on the 7th and 14th day. After the treatment, investigator will follow-up, monitor vital signs, laboratory examination, NIHSS, FMA analysis on 2 weeks, 1 month, and 6 months after the treatment.