稠密而富有光泽的黑头发会给人以美的感觉,带来青春的活力。而头发稀少、干黄,看起来就显得缺乏生气,尤其是少年脱发呈秃或满头银丝,还常常会引起孩子自身和家长的烦恼。那么,为什么年纪轻轻的孩子会出现上述的情况和病态呢? 首先,有必要介绍一下头发的正常生长过程。头发由毛囊中长出,开口于头皮表面。头皮以上的部分叫毛干,也就是人们看得见的头发。埋在头皮下的部分叫毛根。在毛根端有个膨大部,象大蒜头似的,叫毛球。毛球部有突出的东西,叫毛乳头,这些毛乳头与血管神经相连。头发就是通过这些通道,接受各种营养,维持正常的生长。头发的成长过程有一定的周 Dense and shiny black hair gives a sense of beauty and youthful energy. Scarce hair, dry yellow, appears to be lack of vitality, especially young hair loss bald or silver hair, but also often cause their own children and parents worry. So, why young children will appear above the situation and pathological it? First of all, it is necessary to introduce the normal growth of hair. Hair grows in hair follicles, opening in the scalp surface. The part of the scalp called the hair shaft, which is visible hair. Buried in the scalp under the part called hair roots. In the hair root end there is a bulge, like garlic head, called hair ball. Hairball Department has outstanding things, called the hair nipples, these hair nipples and vascular nerves connected. Hair is through these channels, accept a variety of nutrition, to maintain normal growth. Hair growth process has a certain week