Dermoscopic features of clear cell acanthoma

A stem cell is an unspecialized cell that can divide without limit as needed and can, under specific conditions, differentiate into specialized cells.
Adult stem cells
Adult stem cells are tissue-specific; hence, they divide to develop the tissue from which they originate. One type of adult stem cell is the epithelial stem cell, which gives rise to the keratinocytes in the multiple layers of epithelial cells in the epidermis of the skin. Adult bone marrow has three distinct types of stem cells:...

Chronic obstructive pulmonary disease (COPD) is a group of lung conditions that progressively worsen over time, including chronic bronchitis and emphysema. This cluster of diseases collectively leads to a gradual and irreversible decline in lung function over time.
The primary cause for the onset of COPD is cigarette smoking and exposure to air pollution. These hazardous factors initiate a chain reaction within the lungs, resulting in chronic inflammation, damage to the airways, and a...

The adaptive immune system, a crucial component of the overall immune response, offers a highly specialized defense against pathogens. It involves specific cell types and features, enabling it to combat infections effectively and efficiently.
The primary cell types involved in adaptive immunity are T cells and B cells. Each type has a unique role in defending the body against pathogens. T cells are responsible for cell-mediated immunity. They identify and eliminate infected cells directly,...

Patients with esophageal strictures often experience a range of symptoms. Initially, they may have difficulty swallowing solid foods, which can progress to include liquids. Additional symptoms may involve chest pain or discomfort, regurgitating food and fluids, heartburn, unintentional weight loss, coughing or choking during meals, and hoarseness.
Healthcare providers should gather a comprehensive medical history and conduct a physical examination for diagnosis. If esophageal stricture is...

Endocarditis can present various clinical features depending on the causative organism and the patient's underlying health conditions. Initially, the clinical features of infective endocarditis develop gradually, presenting with nonspecific symptoms that can be easily mistaken for other illnesses.General SymptomsEarly symptoms of infective endocarditis are fever, chills, weakness, malaise, fatigue, and weight loss. These symptoms reflect the systemic nature of the infection and the body's...

Pericarditis is distinguished by inflammation of the pericardium, the fibrous sac that encases the heart. It can be acute, lasting less than six weeks, or chronic, persisting for over three months. Understanding its clinical manifestations and diagnostic findings is crucial for timely and effective management.Clinical ManifestationsWhile pericarditis can be asymptomatic, it usually presents with characteristic symptoms such as:Chest Pain: The most characteristic symptom of pericarditis is chest...