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胃能消化掉厚牛排、生菜……等食物,甚至胃酸的浓度足以把锌消化掉,那胃为什么不能消化掉自己呢? 毫无疑问,消化液的确对胃壁有所损伤.每当产生酸时,就有一些细胞被杀死.但是大部分损伤都是暂时性的,这主要是胃有再生能力,从胃壁表面每分钟要脱落50万个细胞,三天之内全部更新. 不过,胃酸并不需要几天而只需要几小时就能将组织溶化掉.如果产生的酸太多,就会形成溃疡.使损伤减少到最小限度,是由于胃粘膜保护层上面覆盖了一层密密的上皮细胞,这层致密细胞起了保护作用.粘膜构成一种自动补充的阻挡层,使大部分酸不能浸透和腐蚀胃的内壁. 但这个阻挡层虽起了保护作用,同样不能解释胃
Stomach can digest thick steaks, lettuce ... ... and other foods, and even the concentration of gastric acid enough to digest zinc, why the stomach can not digest themselves? There is no doubt that digestive juice does damage the stomach wall. , There are some cells were killed, but most of the damage is temporary, mainly due to the regenerative capacity of the stomach, shed 500,000 cells per minute from the surface of the stomach wall, all within three days of update, however, It takes only a few hours to dissolve tissue in less than a few days and, if too much acid is produced, it can form ulcers, minimizing damage due to the dense lining of the gastric mucosal protective layer Cells, this dense layer of cells play a protective role.Mucous constitutes an automatic replenishment of the barrier, most of the acid can not penetrate and corrode the inner wall of the stomach.But this barrier has played a protective role, the same can not explain the stomach