Definition of «old mice»

The phrase "old mice" refers to mice that are not young anymore. It is used to describe mice who are aged or elderly.

Previous studies found better muscle health and stronger healing in old mice receiving blood from a younger counterpart. (sciencemag.org)
The neurons of old mice pumping young blood appeared to grow new places where they could connect with other neurons. (sciencenewsforstudents.org)
The technique also worked on cells from older mice, but not as well. (sciencenewsforstudents.org)
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