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So let me show you the third type of capillary.
下面我們來看第三類毛細血管
So let me show you this last drawing and this is actually the largest of the capillaries.
這是最后一類，這也是毛細血管中最大的一類
And this one we call this a discontinuous capillary
叫做不連續毛細血管
And another name for it, discontinuous capillary, is, sometimes they call it sinusoids
同時還可以叫做血竇
I'm just gonna write that right here as well. Sinusoids.
我寫在這。血竇
So these ones are often found in the liver,
一般存在于肝臟中
that's kind of the most popular place sometimes the spleen as well or bone marrow.
一般在肝臟中，有時候在脾臟或者骨髓中也會有
These ones are actually-few things- are the largest one.
它們是最大的毛細血管
So let me make a little list over here. They are very large.
我寫一下。它們很大
And they have a lot more of this intercellular cleft space.
細胞間隙更多
Look at all these gaps between the cells right
大家看細胞間的間隙
And I'm just going to sketch it in yellow.
我用黃色寫一下
Just to highlight it but there's a lot of gap here between the cells
這樣大家可以看到，細胞之間是有很多間隙的
meaning that these capillaries end up being very leaky.
也就是說，毛細血管是有通透性的
So in addition to being large, they are very leaky
除了非常大之外，血管還有通透性之處
And a final thing about these guys is that unlike the other two capillaries that we've just talked about
最后還需要知道的就是有別于前兩種毛細血管
they have a basement membrane that is often incomplete.
這第三種毛細血管基膜也是不完整的
So as long as there is a whole area missing just like that you might have some basement membrane right here
所以只要有地方是不連續的，基膜就會是這樣
and here but you can see whole chunks are missing. Basement membrane.
這里大家可以看到，缺失的部分基膜也是不連續的
And maybe there's a bit of basement membrane right here.
這里有一塊
So let me write that as a third point.
這是第三點
Incomplete, I'm gonna write BM for basement membrane. Incomplete basement membrane
BM代表基膜，基膜不完整。基膜不完整
So if this is the case, it'll be easier for things to kind of escape, even if you have a little glycocalyx here
那么，物質進出就很方便了，即便這里有隔膜
I'm just drawing a layer of glycocalyx on our discontinuous/sinusoid capillary
我畫一層多糖包被，那么血竇，或者說不連續毛細血管
but, even if you have this glycocalyx
即便存在這層多糖包被
because of the fact that you have all that intercellular cleft space
由于細胞間隙的存在
and you don't have many of the tight junctions, it's gonna be easier for things to get out.
細胞間緊密連接并不多，所以物質離開細胞就非常簡單了
So moving down these three different types you're getting more and more leaky as you go down.
那么這三種類型從上到下，血管的通透性越來越多
So just keep that in mind is that the leakiness of the vessel is increasing
所以大家記住，血管的通透性在增加
In fact the most leaky is this guy down here, the discontinuous type.
實際上，最下邊的這類通透性最多
