Serious Pneumonia and Critical Pneumonia caused by the 2019-nCOV infection greatly threats patients' life, UC-MSCs treatment has been proved to play a role in curing multiple diseases. And this study is conducted to find out whether or not it will function in 2019-nCOV infection Pneumonia. And we are going to get the permission of the enrolled patients. Besides the present clinical treatment, UC-MSCs treatment will be applied to those fulfilling the enrollment. After a period of UC-MSCs treatment, the analysis of UC-MSCs treatment will be completed from related aspects.
