You know them when they're occluded. You know them in the dark.

当有东西挡路的时候你会知道， 即便是在黑暗中。

And this can occlude normal blood flow.

这会阻滞正常血流。

Even parts, that are completely missing from our images or things that are occluded!

甚至连带图中缺失和封闭起来的部分！

The most common pre-hepatic cause is portal vein obstruction, like when there's a thrombus occluding the portal vein and blocking blood flow.

最常见的肝前型病因是门静脉阻塞，例如当有子阻塞门静脉血流时。

Since we have a dense piece of geometry, for instance, hundreds of thousands of hair strands, we have to know how each one occludes the other ones.

我们有了一片密集的几何图形，例如这成百千缕发丝，我们必须知道每一缕发丝是怎么挡住其他发丝的。

The teeth are interlocking, in fact, this tooth which I have of a related sperm whale shows where the opposite tooth came right down here and occluded against this crown.

这些牙齿下交错，，我这颗是它抹香鲸亲戚的牙齿，能看出来对面牙齿直接下来到这里堵住这个牙冠。

The nurse can elicit Trousseau's sign by occluding the brachial or radial artery. Hand and finger spasms that occur during occlusion indicate Trousseau's sign and suggest hypocalcemia.

护士可以通过阻断肱动脉或桡动脉来引出特鲁索(氏)征。阻断期间手和手指痉挛则为特鲁索(氏)征并提示低钙血症。