摘要
Physiologists have done many researches on the mechanism of the intestinal villus absorption. Since the 1970s, Haljamae and Jodal presented serial experimental reports. They believed that there is a countercurrent mechanism in the intestinal villus, so the osmolality in the tip is 2—3 times greater than that in the base. In a conclusive article, Jodal believed that, in accordance with the anatomic considerations, the blood flows from the base to the tip of the intestinal villus in the central arterial vessel, and then descends from the tip to the base in the peripheral capillaries and veins, so that there are opposite blood flowing directions in the intestinal villus which makes the countercurrent mechanism possible. Second, the active pumping of NaCl and passive absorption of water
