斑的种类和形成原因（Types and causes of spots）.docVIP

斑的种类和形成原因（Types and causes of spots） Types and causes of spots One, active spot: Cool acid by the enzyme activity, resulting in unstable, affected by external factors such as illumination and endocrine, color change, can dispel common are: chloasma, sunburn, pregnancy spots, dark spots. Two, qualitative spot: nature is stable, not affected by external factors and change, once removed, the original part will not grow out, common are: genetic spots, freckles, senile plaques, pigmented nevus. Splash characteristics: 1.: freckles is genetic, 3% associated with autosomal and blood, after sun color increase, distribution spots exist in isolation from each other, the diameter of not more than 0.5 cm, often distributed in the face, hands and shoulders, appeared in 5 - 7 years old, not only the eradication of desalination; 2. chloasma: also known as Hu Dieban, liver spots, showing pale brown, flaky patches vary in size, clear boundary, irregular shape, without making the skin, common in the face, symmetrical in the cheeks, mainly with endocrine disorders related to estrogen; 3.: acquired factors, pregnancy, sunburn caused by hormonal changes during pregnancy and ultraviolet, formation of irregular size; 4., black spots: metal spots, rebound spots, the formation of the acquired cosmetics, and long-term use of make-up or heavy metal cosmetics, lead and mercury can be eradicated; 5., senile plaques: medically known as senile pigmented spots. Refers to a plaque lipofuscin pigments in the elderly appears on the skin. 6., drug spots: refers to long-term use or external use of certain hormone drugs, resulting in pigmentation of the skin and other spots formed, and some contraceptives, painkillers, etc., can also cause drug spots. Five major reasons for long spots: 1. external causes: ultraviolet radiation, the use of bad cosmetics, external irritation, abrasions; 2. internal causes: endocrine disorders; A, pregnant way cool acid activity caused by the lead to black pigmentation; B,