It remains unknown whether the rate of cell turnover in diseased hearts____________.
A. changes over time
B. can be monitored
C. is the same as that in healthy hearts
D. is high enough to replace cells faster than they"re dying off
Chronic heart failure is associated with____________.
A. the death of heart cells
B. the life span of a person
C. the effects of pharmaceuticals
D. the weight of the patient
The people who‘re in their mid-70s， only 0.45 percent ofcardiomyocytes____________.
A. are still functional
B. are replaced each year
C. are lost each year
D. are damaged each year
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