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So let me show you the third type of capillary.
下面我们来看第三类毛细血管
So let me show you this last drawing and this is actually the largest of the capillaries.
这是最后一类，这也是毛细血管中最大的一类
And this one we call this a discontinuous capillary
叫做不连续毛细血管
And another name for it, discontinuous capillary, is, sometimes they call it sinusoids
同时还可以叫做血窦
I'm just gonna write that right here as well. Sinusoids.
我写在这。血窦
So these ones are often found in the liver,
一般存在于肝脏中
that's kind of the most popular place sometimes the spleen as well or bone marrow.
一般在肝脏中，有时候在脾脏或者骨髓中也会有
These ones are actually-few things- are the largest one.
它们是最大的毛细血管
So let me make a little list over here. They are very large.
我写一下。它们很大
And they have a lot more of this intercellular cleft space.
细胞间隙更多
Look at all these gaps between the cells right
大家看细胞间的间隙
And I'm just going to sketch it in yellow.
我用黄色写一下
Just to highlight it but there's a lot of gap here between the cells
这样大家可以看到，细胞之间是有很多间隙的
meaning that these capillaries end up being very leaky.
也就是说，毛细血管是有通透性的
So in addition to being large, they are very leaky
除了非常大之外，血管还有通透性之处
And a final thing about these guys is that unlike the other two capillaries that we've just talked about
最后还需要知道的就是有别于前两种毛细血管
they have a basement membrane that is often incomplete.
这第三种毛细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连续的，基膜就会是这样
and here but you can see whole chunks are missing. Basement membrane.
这里大家可以看到，缺失的部分基膜也是不连续的
And maybe there's a bit of basement membrane right here.
这里有一块
So let me write that as a third point.
这是第三点
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，物质进出就很方便了，即便这里有隔膜
I'm just drawing a layer of glycocalyx on our discontinuous/sinusoid capillary
我画一层多糖包被，那么血窦，或者说不连续毛细血管
but, even if you have this glycocalyx
即便存在这层多糖包被
because of the fact that you have all that intercellular cleft space
由于细胞间隙的存在
and you don't have many of the tight junctions, it's gonna be easier for things to get out.
细胞间紧密连接并不多，所以物质离开细胞就非常简单了
So moving down these three different types you're getting more and more leaky as you go down.
那么这三种类型从上到下，血管的通透性越来越多
So just keep that in mind is that the leakiness of the vessel is increasing
所以大家记住，血管的通透性在增加
In fact the most leaky is this guy down here, the discontinuous type.
实际上，最下边的这类通透性最多
