About 4 out of every 100 (4%) people over the ageof 55 years experienced symptoms, but there was evidence of hardening of the arteries in a further 25% of patients who were not experiencing symptoms.
From about the ageof 45 or so initially, the lens gradually hardening, decreased flexibility, ciliary body function has been weakened, and onset of presbyopia.
大约从45岁左右初步，晶状体逐渐硬化、弹性下降，睫状体的功用也在减弱，然后出现老花眼。
3
Temperature deformation and autogenous deformation are the two major forms of deformation ofhardening concrete in early age.