The exact cause of this vasculardegeneration is not known, but it appears to be associated with the absence of melanocytes in the blood vessels.
确切的导致血管的恶化原因不明，但是看起来和血管中黑素细胞的缺乏有关。
2
Results: Hyperemia, swelling, reduction of cell ingredient and variation of blood vessel occurred after refrigeration, The pulp tissue showed vasculardegeneration and fibrosis at ultrastructure.
结果：冷冻后的组织病理特点是充血肿胀，细胞成份减少，血管变异。
3
Hypertension, smoking and diabetes are important factors which contribute to the degeneration of artery compliance, C1 and C2 are sensitive indicators of evaluating vascular-wall abnormalities.