peristalsis


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Related to peristalsis: Reverse peristalsis

peristalsis

 [per″ĭ-stal´sis]
the wormlike movement by which the alimentary canal or other tubular organs with both longitudinal and circular muscle fibers propel their contents, consisting of a wave of contraction passing along the tube. adj., adj peristal´tic.

When food is swallowed, it passes into the esophagus. Muscular contractions in the wall of the esophagus work the food downward, pushing it into the stomach. Here peristaltic contractions not only move the food in small amounts into the intestine but also aid in the disintegration of the food and help mix it with gastric juice. Peristalsis forces the food into and through the intestine for further digestion until the food waste finally reaches the rectum, from which it is periodically discharged from the body. The waves of peristalsis are irregular; they are stronger at some times than at others. They are also weaker in some people, notably the elderly.

Although the normal peristaltic wave is downward, it is sometimes reversed. Reverse peristaltic action may be triggered by mild digestive upsets or more serious disorders, such as an obstruction in the stomach or intestines.

per·i·stal·sis

(per'i-stal'sis),
The movement of the intestine or other tubular structure, characterized by waves of alternate circular contraction and relaxation of the tube by which the contents are propelled onward.
Synonym(s): vermicular movement
[peri- + G. stalsis, constriction]

peristalsis

/peri·stal·sis/ (-stahl´sis) the wormlike movement by which the alimentary canal or other tubular organs having both longitudinal and circular muscle fibers propel their contents, consisting of a wave of contraction passing along the tube for variable distances.peristal´tic

peristalsis

(pĕr′ĭ-stôl′sĭs, -stăl′-)
n. pl. peristal·ses (-sēz)
The wavelike muscular contractions of the digestive tract or other tubular structures by which contents are forced onward toward the opening.

per′i·stal′tic (-stôl′tĭk, -stăl′-) adj.
per′i·stal′ti·cal·ly adv.

peristalsis

[-stal′sis, -stôl′sis]
Etymology: Gk, peri + stalsis, contraction
the coordinated, rhythmic serial contraction of smooth muscle that forces food through the digestive tract, bile through the bile duct, and urine through the ureters.
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Peristalsis

per·i·stal·sis

(per'i-stal'sis)
The movement of the intestine or other tubular structure, characterized by waves of alternate circular contraction and relaxation of the tube by which the contents are propelled onward.
Synonym(s): vermicular movement.
[peri- + G. stalsis, constriction]

peristalsis

A coordinated succession of contractions and relaxations of the muscular wall of a tubular structure, such as the OESOPHAGUS, small intestine or the URETER, producing a wave-like pattern whose effect is to move the contents along.

peristalsis

the alternate contraction and relaxation of circular and longitudinal muscle which produces waves that pass along the intestine (and other tubular systems) of animals, moving the tube contents in one direction.

Peristalsis

A sequence of muscle contractions that progressively squeeze one small section of the digestive tract and then the next to push food along the tract, something like pushing toothpaste out of its tube.

peristalsis

waves of alternate contraction and relaxation in circumferential muscle tissue of a tubular structure, driving contents forward, e.g. movement of blood through the vascular system (see law, Starling's)

peristalsis

the wormlike movement by which the alimentary canal or other tubular organs with both longitudinal and circular muscle fibers propel their contents, consisting of a wave of contraction passing along the tube. Increased peristalsis means faster movement of ingesta through the gut and less absorption of fluid, both tending to diarrhea. Reduced peristalsis means a longer alimentary sojourn, greater inspissation of ingesta and a tendency to constipation. See also peristaltic, paralytic ileus.
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Peristalsis. By permission from Aspinall V, O'Reilly M, Introduction to Veterinary Anatomy and Physiology, Butterworth Heinemann, 2004

reverse peristalsis
peristalsis directed orally is a result of intestinal obstruction and acute, significant distention of the intestinal lumen; it is a major contributing mechanism in vomiting.
References in periodicals archive ?
Segmentation and peristalsis are regulated by the enteric nervous system.
The stimulation of alpha-receptors increases the force of ureteral contraction and the frequency of ureteral peristalsis, whereas the inhibition of alpha-adrenoreceptors has the opposite effect.
After a while it gets to be old hat: stomach acid, peristalsis, intestinal villi, and so on.
This foregut environment tends to be anaerobic, maintains a constant temperature and pH suited to the microbial processes it harbours, and moves gut contents through peristalsis.
Using colorful characters to explain the function of our organs in a straight-forward and age-appropriate manner--the gray Sir Rebrum relates The OrganWise Guys Club Rules (eat a low-fat, high-fiber diet, drink lots of water, and get regular exercise); the Kidney Brothers make clear that bodies need lots of water to keep blood clean; Peter Pancreas tells how he controls sugar by making insulin; Pepto makes the acid pepsin to break down food to be used for energy; to name a few--the Guys expand on topics, such as good and bad cholesterol and peristalsis, in ways that make children understand that how they feel is directly related to how they fuel their bodies.
Peristalsis rotationally compresses the tubing, causing the condensate to move through it.
When the wheat comes through, it brushes it and creates peristalsis and then creates movement, and then a lot of gas is created to push everything out.
Luminal morphology of the avian lower intestine: evidence supporting the importance of retrograde peristalsis for water conservation.
The five hearts that run the length of the worms' bodies help pump the blood that allows them to perform what's called peristalsis, which is moving by contracting and expanding segments up and down the body.
The multiple wire-braided construction is engineered to allow the stent to adjust to forces within the esophagus such as peristalsis (involuntary contractions) and strictures.
Cattlemen have been through this before, and even though the current peristalsis will change the business, perhaps in ways we don't yet comprehend, cattlemen will persevere.
Physiologists term the phenomenon of such transport as peristalsis.