we found that the plasma levels of valine , leucine , isoleucine and proline in patients of any age , the levels of hydroxyproline and phenylalanine in subjects over the age of 45 and the levels of ornithine in subjects under the age of 45 , are higher in men , while the level of threonine is higher in women under the age of 45 than in men of the same age .
C0033382
proline
C0020388
hydroxyproline