Скачать с ютуб 为什么人每天都会掉头发 脱发的病因有哪些 肖玉凤 贵阳市第二人民医院 в хорошем качестве

为什么人每天都会掉头发 脱发的病因有哪些 肖玉凤 贵阳市第二人民医院

为什么人每天都会掉头发 脱发的病因有哪些 肖玉凤 贵阳市第二人民医院 正常人的头发一般在10万到15万根，由于遗传和种族的差异，每个人的头发数量也是会有差异的。头发有生长周期，可以分为生长期、退行期、休止期。各个部位的毛发并非同时生长或脱落，平均每天掉发在100根之内都是正常的，掉发的同时每天也会有等量的新发生长。脱发的病因可以分为先天因素和后天因素。先天因素是指在胚胎时期没有形成毛囊，从而导致一出生就无头发生长，这种原因引起的脱发后天再生头发的几率很小。后天因素是指头发的生长周期缩短，而退化期和休止期相对延长，或者是毛囊受到各种物理或化学影响而破坏萎缩，从而导致脱发。 What are the causes of hair loss every day Normal people usually have 100000 to 150000 hairs, Because of genetic and ethnic differences, There will also be differences in the number of hairs per person. Hair has a growth cycle, It can be divided into growth period, retrograde period and rest period. Hair does not grow or fall off at the same time, It's normal to lose 100 Hair per day, The same amount of new hair will grow every day. The causes of hair loss can be divided into congenital factors and acquired factors. Congenital factors refer to the absence of hair follicles in the embryo, This leads to hair free growth at birth, The probability of hair regeneration after hair loss caused by this reason is very small. Postnatal factors are the shortening of hair growth cycle, However, the degradation period and the rest period are relatively prolonged, Or the hair follicles are damaged and atrophied by various physical or chemical influences, This leads to hair loss.