Delta

From WikiMD.org
Jump to navigation Jump to search

Delta (Δ or δ)

Delta (pronounced /ˈdɛltə/; uppercase Δ, lowercase δ) is the fourth letter of the Greek alphabet. In the system of Greek numerals, it has a value of 4. It is derived from the Phoenician letter dalet 𐤃, which means "door".

In the context of medicine, Delta has several meanings:

1. Delta wave: A type of high amplitude brain wave found in humans. Delta waves are usually associated with the deep stage 3 of NREM sleep, also known as slow-wave sleep (SWS), and aid in characterizing the depth of sleep.

2. Delta variant: A variant of SARS-CoV-2, the virus that causes COVID-19. The Delta variant was first identified in India in October 2020.

3. Delta cell: A type of cell in the pancreas. Delta cells produce the hormone somatostatin, which regulates the endocrine system.

4. Delta receptor: One of three types of opioid receptors in the brain. Delta receptors are associated with analgesic effects.

5. Delta hepatitis: A type of hepatitis caused by the hepatitis D virus (HDV). Delta hepatitis is unique because it requires the presence of the hepatitis B virus (HBV) to replicate.

Etymology

The term Delta is derived from the Ancient Greek word δέλτα (délta), which was named after the Phoenician letter dalet. The word "delta" comes from the shape of the uppercase letter Δ, which resembles a triangle or the shape of the Nile Delta.

Related terms

External links

Esculaap.svg

This WikiMD article is a stub. You can help make it a full article.


Languages: - East Asian 中文, 日本, 한국어, South Asian हिन्दी, Urdu, বাংলা, తెలుగు, தமிழ், ಕನ್ನಡ,
Southeast Asian Indonesian, Vietnamese, Thai, မြန်မာဘာသာ, European español, Deutsch, français, русский, português do Brasil, Italian, polski