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Adenomyoma of the jejunum

Xin Qing1, Beverley A Petrie, Virgil Buslon

  • 1Department of Pathology, Harbor-UCLA Medical Center, Torrance, CA 90509, USA.

Related Concept Videos

Appendicitis01:19

Appendicitis

Appendicitis is an acute inflammatory condition of the vermiform appendix, most commonly caused by obstruction of its lumen. The appendix is a narrow, blind-ended pouch that extends from the cecum, making it particularly prone to obstruction. Causes include fecaliths, lymphoid hyperplasia (often after viral infections), parasites, tumors, or foreign bodies. This obstruction initiates a cascade of pathological changes.Luminal Obstruction and Early InflammationAfter obstruction, normal mucosal...
Diverticular Disease of the Colon01:27

Diverticular Disease of the Colon

Diverticular disease involves the formation of diverticula—small sac-like outpouchings of the colonic wall—and their complications. It most commonly affects the sigmoid colon due to higher intraluminal pressure and structural vulnerability. It results from structural weakness and increased pressure in the colon, producing pseudodiverticula that may remain silent or progress to inflammation and serious complications.Structure of DiverticulaIn diverticulosis, these outpouchings are...
Histology of the Small Intestine01:27

Histology of the Small Intestine

The small intestine exhibits a unique histological structure that significantly enhances its function in digestion and nutrient absorption. These structures include circular folds, villi, and various specialized cells that collectively facilitate the digestion of food.
The intestinal lining features transverse folds called circular folds, each housing fingerlike projections known as intestinal villi. These villi are covered by a layer of simple columnar epithelium, also referred to as...
Lower GI Series: Barium Enema01:23

Lower GI Series: Barium Enema

A Barium Enema, or a lower GI series, is a specialized radiographic examination designed to visualize the lower gastrointestinal tract, specifically the colon and rectum. This procedure is instrumental in diagnosing various conditions such as colorectal cancer, polyps, diverticulosis, and inflammatory bowel disease.
Procedure Details
The examination begins by inserting a lubricated rectal tube into the patient's rectum to administer a radiopaque barium solution. The barium flow is carefully...
Mucosal Barrier of the Stomach01:25

Mucosal Barrier of the Stomach

The gastric glands contain parietal cells that secrete hydrochloric acid (HCl) for digestion. The cells secrete HCl because it is highly corrosive and essential for breaking down food. To achieve this, they secrete hydrogen and chloride ions into the lumen of the gastric glands, which combine to form HCl.
Within parietal cells, carbonic acid is first formed through the reaction of water and carbon dioxide. The dissociation of carbonic acid releases bicarbonate and hydrogen ions. The bicarbonate...
Intestinal Obstruction II: Pathophysiology01:07

Intestinal Obstruction II: Pathophysiology

Intestinal obstruction triggers a series of physiological responses, starting with gas and fluid accumulation in the bowel segment proximal to the obstruction, leading to distension. This distended intestine compresses the diaphragm, hindering lung expansion and potentially leading to reduced respiratory effort, atelectasis, and pneumonia.To overcome the blockage, the gut intensifies contractions, causing colicky abdominal pain, nausea, and vomiting, which reduces fluid and food intake and...