Health encyclopaedia - Alphabetical Topic List健康百科全书-按字母顺序排列的主题清单
| | A | | 1 | | | B | | b | | | C | | 人才招聘 | | | D | | | | | E | | 电子 | | | F | | f | | | G | | 克 | | | H | | h | | | I | | 我 | | | J | | j | | | K | | k | | | L | | 升 | | | M | | 米 | |
| | N | | n | | | O | | o | | | P | | p | | | Q | |常见问题 | | | R | | 研究 | | | S | | | | | T | | 吨 | | | U | | u | | | V | | v | | | W | | 瓦特 | | | X | | x | | | Y | | y | |
Causes of Hair loss原因脱发
The average human head has 100,000 hairs.平均人体头部有十万头发。 Hair is made in hair follicles (the root of the hair).头发是在毛囊（的根头发） 。 Each hair grows for about 3 years then it drops out and a new one grows - we lose 40-120 hairs a day (1).每个头发生长约三年，然后它被丢弃和一个新的增长-我们失去了4 0-120毛1天（ 1 ） 。
Male-pattern and female-pattern baldness is caused by over-sensitive hair follicles. 男性型和女性秃顶的原因是过度敏感的毛囊。 This is linked to dihydrotestosterone (DHT) that is produced by the male hormone testosterone.这是联系在一起的双氢睾酮（ dht ）即是所产生的雄性激素睾酮。 If there is too much DHT, the follicles shrink, so the hair becomes thinner and grows for less time than normal.如果有太多的dht ，卵泡萎缩，使头发变得更薄和增长不足的时间比正常。 The balding process is gradual because different follicles are affected at different times.该秃顶的过程是循序渐进的，因为不同的卵泡受影响的在不同的时间。
Alopecia areata is linked to a problem with the immune system. The hair follicles are not permanently damaged and in many of these cases the hair grows back in a few months. 斑秃是联系在一起的问题，与免疫系统。毛囊是不会永久损坏，而且在许多情况下这些头发生长早在数个月。 In 1 in 5 cases it runs in the family (2).在1 5例，它违背了在家庭中（ 2 ） 。
Some conditions such as anaemia (disorder of the blood), illness, stress (including bereavement), fungal infections and thyroid problems can make you lose some of your hair, as well as drug treatment for cancer.一些条件，如贫血（紊乱，血液） ，生病，应力（包括亲属丧亡之痛） ，真菌感染和甲状腺问题，可以使你失去一些你的头发，以及药物治疗癌症。 Women who are pregnant or have recently given birth may also experience some hair loss.妇女谁怀孕或有刚分娩，也可能会遇到一些脱发。 Hair loss is not caused by a lack of any vitamins in the diet.脱发是不是不足而引致的任何维生素的饮食。
