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Pemphigus vulgaris presenting in a radiation portal

Amber C Robbins1, Zelmira Lazarova, Marleen M Janson

  • 1Department of Dermatology, Medical College of Wisconsin, Milwaukee, USA.

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Portal Hypertension01:22

Portal Hypertension

Portal hypertension is an increase in blood pressure within the portal venous system. Normally, this pressure is less than 5 mmHg. It is considered clinically significant when it rises above 10 mmHg. At this threshold, complications from altered blood flow and venous congestion emerge.EtiologyPortal hypertension arises from conditions that impede blood flow through the liver. The most common cause is cirrhosis, in which chronic liver injury leads to fibrotic scarring. This fibrosis narrows or...
Peptic Ulcer01:27

Peptic Ulcer

Peptic ulcers are erosive lesions of the gastric or duodenal lining, most commonly caused by Helicobacter pylori infection. This Gram-negative, helical bacterium has adapted to survive the stomach’s acidic environment by producing urease, which converts urea into ammonia and carbon dioxide. The ammonia neutralizes gastric acid in the bacterium’s immediate environment, allowing colonization of the gastric mucosa. H. pylori attaches to mucus-secreting epithelial cells, penetrates the mucus...
Absorption of Radiation01:05

Absorption of Radiation

The rate of heat transfer by emitted radiation is described by the Stefan-Boltzmann law of radiation:
Skin Cancer01:30

Skin Cancer

Skin cancer is a type of cancer that occurs when there is an abnormal growth of skin cells, usually triggered by damage to the DNA within the skin cells. It is primarily caused by exposure to ultraviolet (UV) radiation from the sun or artificial sources like tanning beds. Skin cancer is the most common type of cancer worldwide, and its incidence continues to rise.
Basal Cell Carcinoma (BCC): BCC is the most common type of skin cancer, accounting for about 80% of cases. It typically develops in...
Peptic Ulcer Disease I: Introduction01:30

Peptic Ulcer Disease I: Introduction

Peptic Ulcer Disease (PUD) is characterized by mucosal excavation in the esophagus, stomach, pylorus, or duodenum. It can manifest as acute or chronic based on the extent and duration of mucosal involvement.
An acute ulcer, marked by superficial erosion and minimal inflammation, swiftly resolves upon identifying and addressing the underlying cause. In contrast, a chronic ulcer persists, potentially eroding through the muscular wall and forming fibrous tissue.
Peptic ulcers can also be...
Peptic Ulcer Disease III: Clinical Manifestations and Complications01:25

Peptic Ulcer Disease III: Clinical Manifestations and Complications

Duodenal UlcersDuodenal ulcers are the most common form of peptic ulcer disease, presenting with chronic, intermittent epigastric pain. Pain typically appears 2–3 hours after meals, especially when the stomach is empty, often waking patients at night. It is characteristically relieved by food or antacids (“pain–food–relief”). Some patients remain asymptomatic until complications like bleeding or perforation emerge, particularly with NSAID or anticoagulant use.Gastric UlcersGastric ulcers share...