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Showing posts with label liver. Show all posts
Showing posts with label liver. Show all posts

Architecture of the Liver

The liver is the largest organ in the body. Liver tissue is composed of a compact mass of multisided units, known as the hepatic lobules. Each lobule consists of a central vein, which acts as a tributary of the hepatic vein and conducts processed blood away from the lobule, surrounded by plates of liver cells. The liver receives blood from two sources, 80 percent, which carries digested food materials, arrives from the intestine via the portal vein and venules; the remaining twenty percent is oxygenated blood from the heart, which enters through the hepatic artery and arterioles. An exchange of materials takes place between the liver cells and the blood, which then passes into the central veins and returns to the general body circulation via the hepatic vein. Sinusoids, spaces between plates of liver cells composed of tributaries of the hepatic artery and portal vein, conduct the blood flow to the central vein. The bile canaliculus carries bile juice from the liver to branches of the bile duct which convey bile from the lobules to the gall bladder. When an adult is at rest, about two and a half pints of blood flow through the liver each minute.

Hepatitis C

Hepatitis C is an infectious disease affecting the liver, caused by the hepatitis C virus (HCV).[1] The infection is often asymptomatic, but once established, chronic infection can progress to scarring of the liver (fibrosis), and advanced scarring (cirrhosis). In some cases, those with cirrhosis will go on to develop liver failure or other complications of cirrhosis, including liver cancer. The hepatitis C virus (HCV) is spread by blood-to-blood contact. Most people have few symptoms after the initial infection, yet the virus persists in the liver in about 80% of those infected. Persistent infection can be treated with medication, such as interferon and ribavirin, and currently over half are cured overall. Those who develop cirrhosis or liver cancer may require a liver transplant, although the virus generally recurs after transplantion.


Hepatitis B and C

Hepatitis B virus infects the liver of hominoidae, including humans, and causes an inflammation called hepatitis. It is a DNA virus and one of many unrelated viruses that cause viral hepatitis. The disease, originally known as "serum hepatitis", has caused epidemics in parts of Asia and Africa, and it is endemic in China. About a third of the world's population, more than 2 billion people, have been infected with the hepatitis B virus. This includes 350 million chronic carriers of the virus. The acute illness causes liver inflammation, vomiting, jaundice and—rarely—death. Chronic hepatitis B may eventually cause liver cirrhosis and liver cancer—a fatal disease with very poor response to current chemotherapy.The infection is preventable by vaccination.


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Hepatitis C is a blood-borne infectious disease that is caused by the hepatitis C virus (HCV), affecting the liver. The infection is often asymptomatic, but once established, chronic infection can cause inflammation of the liver (chronic hepatitis). This condition can progress to scarring of the liver (fibrosis), and advanced scarring (cirrhosis). In some cases, those with cirrhosis will go on to develop liver failure or other complications of cirrhosis, including liver cancer.

The hepatitis C virus (HCV) is spread by blood-to-blood contact. No vaccine against hepatitis C is available. The symptoms of infection can be medically managed, and a proportion of patients can be cleared of the virus by a course of anti-viral medicines. Although early medical intervention is helpful, people with HCV infection can experience mild symptoms, and consequently do not seek treatment. An estimated 150-200 million people worldwide are infected with hepatitis C.