It's one of many sphincters on your body.

它是你身体上的约肌之一。

You mock the sphincter but the sphincter is a class of muscle without which human beings couldn't survive.

你居然嘲笑约肌 约肌可是人体的一组肌肉 没有的话人类没法存活的哦。

There are two little sphincters that control when to release your urine from the bladder.

有两个小约肌控制何时从胱中释放尿液。

Both relax during swallowing to allow the passage of food or liquids.

上述两个约肌依次松弛，以吞咽食或液体。

Sleeping on the right relaxes the lower oesophageal sphincter, allowing the acid to escape.

而右侧睡觉会松弛下食道约肌，使胃酸逃脱。

There are over 50 different sphincters in the human body. How many can you name?

人体内共有超过50种不同的约肌 你能叫出多少？

You may also stretch your external sphincter muscles.

你也有可能会撑大你的外约肌。

Typically, that internal sphincter muscle opens up when the bladder is about half full.

一胱充盈量达到一半时，内约肌会开放。

And it's the same color as my cadaver's esophageal sphincter.

而且，这甜品的颜色跟我解剖尸体的食管约肌一样。

The internal urethral sphincter automatically and involuntarily opens, and the urine is released.

尿道内约肌自然而然的张开，尿就排出来了。

When you want to delay urinating, you keep the sphincter closed.

你想憋尿时，约肌就会关上。

It also decreases motor nerve stimulation to the external sphincter allowing it to relax as well.

其同时减少运动神经元对外约肌的刺激，使其舒张。

These parasympathetic neurons make the rectum contract and the internal anal sphincter relax.

这些副交感神经元可以使直肠收缩，并使肛门内约肌松弛。

Simultaneously, the internal urethral sphincter opens. This is called the micturition reflex.

同时，约肌内壁开始打开。这叫做排尿反射。

Additionally, the lower esophageal sphincter is tightly closed between meals to prevent acid reflux.

另外，食管下约肌在不进食时会保持强力收缩状态，来防止胃酸返流。

The lower esophageal sphincter has a resting pressure of 10 to 45 millimeters of mercury.

食管下约肌的静息压力为10至45毫米汞柱。

Stress incontinence treatments typically focus on strengthening the external sphincter muscle by doing things like Kegel exercises.

压力性尿失禁的治疗侧重增强外约肌的收缩力，例如通过做Kegel运动。

This system also controls the iris sphincter muscle.

该系统还控制虹膜约肌。

The sphincter wants to keep the camera out.

约肌排斥镜头进去。

So now you know that you’ve got a sphincter in your eye.

所以现在你知道你的眼睛里有一个约肌。