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Let me now show you a second drawing that I did.
下面來看第二種
This is our second type of capillary.
這是第二種毛細血管
This is a fenestrated capillary.
這是有孔毛細血管
You can see the major difference between this one and the first one is that the second one has little holes.
大家可以看到第一種和第二種毛細血管的區別，就是第二種血管有小孔
We call them fenestrations. Fenestrations
這是血管的孔
So this is a fenestrated capillary.
這是有孔毛細血管
And these pores. I'm gonna just label them.
而這些小孔，我標記一下
You can also call them pores or holes.
這叫做小孔，或者小洞
These pores are all over the capillary. Right?
毛細血管上都有小孔
So we still have, just as before, four cells, four nuclei and one little red blood cell poking its way through.
還是跟第一個一樣，有四個細胞，有一個紅細胞在其中穿過
And you still have the intercellular cleft.
還是有細胞間隙
So, just to show you where it is on this one,
大家看這個位置
it's right there where the two cells really don't meet up so nicely.
在這里，兩個細胞不接觸的地方
There's a little gap there.
這有一個間隙
And as before there is going to be a basement membrane.
外面是一層基膜
So I'm just gonna sketch out the basement membrane all the way around.
我們把基膜畫全
And on this cross section you can see now
在橫截面看的話
how I've tried to draw as best as I can to show you the pores
我盡量表示出小孔來
but you have to kind of now get a little creative
不過要分清細胞間隙和小孔
and see where that intercellular cleft is versus where the pores are.
大家要用自己想象力了
So whenever you're looking at the cross-section, it is a little tricky
看橫截面的時候是需要一定技巧的
cause you have to almost imagine it in three dimensions.
因為是三維圖像，大家要想象它是立體的
Now the one thing that does help us is the fact that on the inside of these endocellular cells,
有個結構可以幫助區分細胞間隙和小孔，這些細胞內有一層粘液
there is, I'm gonna draw in blue, a little layer of, almost like a slime.
我用藍色畫
And this slime layer is called Glycocalyx. Glycocalyx.
這個粘液層是多糖包被
And what glycocalyx is, is basically sugars that are attached to proteins.
而多糖包被就是糖類和蛋白質結合在一起
This kind of sugary protein mix is all over the inside layer of these endocellular cells
這種糖類蛋白質混合物存在于這些細胞的內層
and so what it does is that it actually gets across these pores.
所以可以覆蓋血管的小孔
And even though there is a pore there, you might get a little glycocalyx spanning in the pore,
雖然外層看是有孔的，從內層看，孔的表面有多糖包被覆蓋
and it will come across and look like that.
就像這樣
The one place where you won't see it is in the intercellular cleft
唯一不存在多糖包被的地方，就是細胞間隙
cause that's actually a real spot between cells.
因為這是細胞間的一個斷裂
So you have the intercellular cleft like you do here, let me just draw an arrow down there.
這里是細胞間隙，我畫一個箭頭
Right there, you won't see any glycocalyx there
這里是沒有多糖包被的
So we call that little bit of glycocalyx that's bridging the pore, we call that the diaphragm. Diaphragm.
那么覆蓋小孔的多糖包被，就是隔膜
So these cells.
那么這些細胞
So these fenestrated capillaries actually have diaphragm over their pores.
有孔毛細血管在小孔上都有隔膜
And I'm gonna put a little star next to that
不過這里要寫一個星號
because sometimes you can find fenestrated capillaries that do not have this glycocalyx
因為有的有孔毛細血管內層并沒有多糖包被
that's covering the inside and they therefore do not have diaphragm.
所以不存在隔膜
So this is something that is generally true but not always true.
這只是一般的規律
