Brown B P, Schulze-Delrieu K, Schrier J E, Abu-Yousef M M
Department of Radiology, University of Iowa Hospitals and Clinics, Iowa City.
Gastroenterology. 1993 Aug;105(2):433-40. doi: 10.1016/0016-5085(93)90717-q.
The stomach separately empties liquids and large particulate solids. The present study aimed to better define the mechanisms responsible for this separate emptying in humans.
Real-time ultrasound images of the gastroduodenal junction were tape-recorded in normal volunteers after they ingested a test meal consisting of beans and chicken broth.
During early emptying, beans were retained along the gastric greater curve as it bulged caudally. When the pylorus was open, liquids flowed over the beans into the duodenum. Emptying of the occasional bean that appeared in the antrum was blocked by closure of the pylorus. Later, the antrum was tubular in shape with reduced area of cross section, yet the percent narrowing of the lumen with each contraction remained constant. Beans were now in close contact with the contracting antral wall and were transformed into small particles. Only in this state were solids allowed through the pylorus.
Mechanisms by which the human stomach "sieves" liquids from solids include (1) sedimentation of solids in the dependent portion of the stomach, while liquids are "decanted" into the duodenum in early emptying; (2) blockade of large particles from entering the duodenum by closure of the pylorus; and (3) grinding of large particles by the gastric antrum in late emptying.
胃分别排空液体和大颗粒固体。本研究旨在更好地确定人类这种分别排空的机制。
在正常志愿者摄入由豆类和鸡汤组成的试验餐后，对胃十二指肠交界处的实时超声图像进行录像。
在早期排空期间，随着胃大弯向尾侧膨出，豆类沿胃大弯潴留。当幽门开放时，液体越过豆类流入十二指肠。胃窦中偶尔出现的豆类排空被幽门关闭所阻断。后来，胃窦呈管状，横截面积减小，但每次收缩时管腔的狭窄百分比保持不变。此时豆类与收缩的胃窦壁紧密接触并被转化为小颗粒。只有在这种状态下固体才被允许通过幽门。
人类胃从固体中“筛出”液体的机制包括：（1）在早期排空时，固体在胃的下垂部分沉降，而液体被“倾析”到十二指肠；（2）幽门关闭阻止大颗粒进入十二指肠；（3）在后期排空时胃窦对大颗粒进行研磨。
