指甲是皮肤附属器官之一,它由坚硬的角质组成,和皮肤一样,是保护人体的防线之一。指甲由甲根部的甲母质产生,由后向前缓慢生长,一般从甲根长到甲前极需要3个月左右,儿童指甲生长较快,而老年人则缓慢。正常健康的指甲表面光滑,呈半透明状,稍发红,两侧稍向下弯曲呈弧形。指甲也是观察人体健康的一面镜子,皮肤以至全身情况常 Nail is one of the appendages attached to the skin. It is made up of hard cutin, which, like the skin, is one of the defenses against the human body. The nails are produced from the nail base of the root part and grow slowly from the back to the front. It usually takes about 3 months to grow from the root to the nail. Children’s nails grow faster, while the aged people are slow. Normal and healthy nails smooth, translucent, slightly red, curved slightly downward on both sides of the arc. Nails is also a mirror to observe human health, the skin and the body often