Fig. 2From: Exosomal miRNA-128-3p from mesenchymal stem cells of aged rats regulates osteogenesis and bone fracture healing by targeting Smad5a The morphology of Young-Exos and Aged-Exos (scale: 100Â nm). b The diameter of Young- and Aged-Exos, ranging from 50 to 150Â nm. c Specific surface markers of exosomes, including CD63 and CD81Back to article page