Liver Blood Tests Glossary of Terms

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Abdominal: Relating to the abdomen, the belly, that part of the body that contains all of the structures between the chest and the pelvis. The abdomen is separated anatomically from the chest by the diaphragm, the powerful muscle spanning the body cavity below the lungs.
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Abdominal pain: Pain in the belly (the abdomen). Abdominal pain can come from conditions affecting a variety of organs. The abdomen is an anatomical area that is bounded by the lower margin of the ribs above, the pelvic bone (pubic ramus) below, and the flanks on each side. Although abdominal pain can arise from the tissues of the abdominal wall that surround the abdominal cavity (the skin and abdominal wall muscles), the term abdominal pain generally is used to describe pain originating from organs within the abdominal cavity (from beneath the skin and muscles). These organs include the stomach, small intestine, colon, liver, gallbladder, and pancreas.
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Abnormal: Not normal. Deviating from the usual structure, position, condition, or behavior. In referring to a growth, abnormal may mean that it is cancerous or premalignant (likely to become cancer).

Acetaminophen: A pain reliever and fever reducer. Brand name: Tylenol. The exact mechanism of action of acetaminophen is not known. Acetaminophen relieves pain by elevating the pain threshold (that is, by requiring a greater amount of pain to develop before it is felt by a person). Acetaminophen reduces fever through its action on the heat-regulating center (the "thermostat") of the brain. Generic is available.

Acute: Of abrupt onset, in reference to a disease. Acute often also connotes an illness that is of short duration, rapidly progressive, and in need of urgent care.
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Alanine: An amino acid, one of the 20 building blocks of protein. Alanine is not an "essential" amino acid. It is not essential to the diet, but can be made by the body from other substances. Alanine was discovered in protein in 1875. Symbol: Ala.

Albumin: The main protein in human blood and the key to the regulation of the osmotic pressure of blood. Chemically, albumin is soluble in water, precipitated by acid, and coagulated by heat.
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Alcohol abuse: Use of alcoholic beverages to excess, either on individual occasions ("binge drinking") or as a regular practice. For some individuals-children or pregnant women, for example-almost any amount of alcohol use may be legally considered "alcohol abuse," depending on local laws. Heavy alcohol abuse can cause physical damage and death.

Aleve: See: Naproxen.

Alkaline phosphatase: An enzyme made in the liver, bone, and the placenta and normally present in high concentrations in growing bone and in bile. Alkaline phosphatase is released into the blood during injury and during such normal activities as bone growth and pregnancy. It is measured in a routine blood test.
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Amino acids: The building blocks of polypeptides and proteins.

Aminotransferase: An enzyme that catalyzes the transfer of an amino group from a donor molecule to a recipient molecule. The donor molecule is usually an amino acid while the recipient (acceptor) molecule is usually an alpha-2 keto acid. An aminotransferase is also called a transaminase. Two of the better known enzymes in this class are serum glutamic oxaloacetic transaminase (SGOT) and serum glutamic pyruvic transaminase (SGPT). Both of these transaminases (SGOT and SGPT) are normally found primarily in cells in the liver and heart, are released into the bloodstream as the result of liver or heart damage, and so are used as liver and heart tests.

Antidepressants: Anything, and especially a drug, used to prevent or treat depression.
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Atorvastatin: A medication that lowers the level of cholesterol in the blood. Atorvastatin is a statin drug. All statins prevent the production of cholesterol in the liver by blocking the enzyme that makes cholesterol, HMGCoA reductase. They lower total blood cholesterol as well as low-density lipoprotein (LDL) cholesterol levels. Lowering LDL cholesterol levels retards progression and may even reverse coronary artery disease. Unlike the other statins, atorvastatin can also reduce the concentration of triglycerides in the blood. (High blood concentrations of triglycerides have been associated with coronary artery disease.) The brand name of atorvastin is Lipitor.

Autoimmune: Pertaining to autoimmunity, a misdirected immune response that occurs when the immune system goes awry and attacks the body itself.
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Autoimmune hepatitis: A disease in which the body's immune system attacks liver cells, causing inflammation of the liver (hepatitis). If not treated, autoimmune hepatitis can lead to cirrhosis (scarring and hardening) of the liver and eventually to liver failure.

Bile: Bile is a yellow-green fluid that is made by the liver, stored in the gallbladder and passes through the common bile duct into the duodenum where it helps digest fat. The principal components of bile are cholesterol, bile salts, and the pigment bilirubin.
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Biliary: Having to do with the gallbladder, bile ducts, or bile. The biliary system itself consists of the gallbladder and bile ducts and, of course, the bile.
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Bilirubin: A yellow-orange compound produced by the breakdown of hemoglobin from red blood cells.

Blood count: The calculated number of white or red blood cells (WBCs or RBCs) in a cubic millimeter of blood.

Blood transfusion: The transfer of blood or blood components from one person (the donor) into the bloodstream of another person (the recipient). This may be done as a lifesaving maneuver to replace blood cells or blood products lost through bleeding. Transfusion of your own blood (autologous) is the safest method but requires advance planning and not all patients are eligible. Directed donor blood allows the patient to receive blood from known donors. Volunteer donor blood is usually most readily available and, when properly tested has a low incidence of adverse events. Blood conserving techniques are an important aspect of limiting transfusion requirements.
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Bowel: Another name for the intestine. The small bowel and the large bowel are the small intestine and large intestine, respectively.
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Cancer: An abnormal growth of cells which tend to proliferate in an uncontrolled way and, in some cases, to metastasize (spread).
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Carcinoma: Cancer that begins in the skin or in tissues that line or cover body organs. For example, carcinoma can arise in the breast, colon, liver, lung, prostate, and stomach.

Chronic: This important term in medicine comes from the Greek chronos, time and means lasting a long time.
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Cirrhosis: An abnormal liver condition characterized by irreversible scarring of the liver. Alcohol and viral hepatitis B and C are among the many causes of cirrhosis. Cirrhosis can cause yellowing of the skin (jaundice), itching, and fatigue. Diagnosis of cirrhosis can be suggested by physical examination and blood tests, and can be confirmed by liver biopsy in some patients. Complications of cirrhosis include mental confusion, coma, fluid accumulation (ascites), internal bleeding, and kidney failure. Treatment of cirrhosis is designed to limit any further damage to the liver as well as complications. Liver transplantation is becoming an important option for patients with advanced cirrhosis.

Coagulation: In medicine, the clotting of blood. The process by which the blood clots to form solid masses, or clots.
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Colitis: Inflammation of the large intestine (the colon). There are many forms of colitis, including ulcerative colitis, Crohn's disease, infectious, pseudomembranous, and spastic. For example, intermittent rectal bleeding, crampy abdominal pain and diarrhea can be symptoms of ulcerative colitis. Diagnosis can be made by barium enema, but direct visualization (sigmoidoscopy or colonoscopy) is the most accurate test. Long-standing ulcerative colitis increases the risk for colon cancer. Ulcerative colitis can also be associated with inflammation in joints, spine, skin, eyes, the liver and its bile ducts. Treatment of ulcerative colitis can involve medications and surgery.

Complete blood count: A set values of the cellular (formed elements) of blood. These measurements are generally determined by specially designed machines that analyze the different components of blood in less than a minute.
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Crohn's disease: A chronic inflammatory disease, primarily involving the small and large intestine, but which can affect other parts of the digestive system as well. It is named for Burrill Crohn, the American gastroenterologist who first described the disease in 1932.
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Duct: A passage or a tube with well-defined walls suitable for the conveyance of air or liquids, as the bile duct and the pancreatic duct.
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Electrolyte: An electrolyte is a substance that will dissociate into ions in solution and acquire the capacity to conduct electricity. The electrolytes include sodium, potassium, chloride, calcium and phosphate. Informally, called lytes. (The clue to the word electrolyte is in the lyte which comes from the Greek lytos meaning that may be dissolved.)

Enzyme: A protein (or protein-based molecule) that speeds up a chemical reaction in a living organism. An enzyme acts as catalyst for specific chemical reactions, converting a specific set of reactants (called substrates) into specific products. Without enzymes, life as we know it would not exist.
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Enzymes: Proteins that act as a catalysts in mediating and speeding a specific chemical reaction.
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Fatigue: A condition characterized by a lessened capacity for work and reduced efficiency of accomplishment, usually accompanied by a feeling of weariness and tiredness. Fatigue can be acute and come on suddenly or chronic and persist.
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Fever: Although a fever technically is any body temperature above the normal of 98.6 degrees F. (37 degrees C.), in practice a person is usually not considered to have a significant fever until the temperature is above 100.4 degrees F (38 degrees C.).
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Gallbladder: A pear-shaped organ just below the liver that stores the bile secreted by the liver. During a fatty meal, the gallbladder contracts, delivering the bile through the bile ducts into the intestines to help with digestion. Abnormal composition of bile leads to formation of gallstones, a process termed cholelithiasis. The gallstones cause cholecystitis, inflammation of the gallbladder.

Gallstones: Stones that form when substances in the bile harden. Gallstones can be as small as a grain of sand or as large as a golf ball. There can be just one large stone, hundreds of tiny stones, or any combination.
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Genetic: Having to do with genes and genetic information.

Glucose: The simple sugar (monosaccharide) that serves as the chief source of energy in the body. Glucose is the principal sugar the body makes. The body makes glucose from proteins, fats and, in largest part, carbohydrates. Glucose is carried to each cell through the bloodstream. Cells, however, cannot use glucose without the help of insulin. Glucose is also known as dextrose.
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Glutamate: A form of glutamic acid. See: Glutamic acid.

Heart: The muscle that pumps blood received from veins into arteries throughout the body. It is positioned in the chest behind the sternum (breastbone; in front of the trachea, esophagus, and aorta; and above the diaphragm muscle that separates the chest and abdominal cavities. The normal heart is about the size of a closed fist, and weighs about 10.5 ounces. It is cone-shaped, with the point of the cone pointing down to the left. Two-thirds of the heart lies in the left side of the chest with the balance in the right chest.
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Hemochromatosis: Hemochromatosis (iron overload) is an inherited disorder in how the body absorbs and stores iron. The excess iron gives the skin a bronze color and damages the liver and other organs. Diabetes is also a part of the syndrome due to damage to the pancreas.

Hepatic: Having to do with the liver. Pronounced hi-'pa-tik. From the Latin hepaticus derived from the Greek hepar meaning (not too surprisingly) the liver.

Hepatitis: Inflammation of the liver from any cause.
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Hepatitis A: Inflammation of the liver caused by the hepatitis A virus (HAV). HAV is usually transmitted from person to person by food or drink that has been contaminated with the stool of a person with hepatitis A. This type of transmission is called "fecal-oral." The virus is more easily spread in areas where there are poor sanitary conditions or where good personal hygiene is not observed. In 2003 there were hepatitis A outbreaks in the US associated with eating raw or lightly cooked green onions (scallions). Casual contact, as in a school, office, or another work setting, does not spread the virus.
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Hepatitis B: Inflammation of the liver due to the hepatitis B virus (HBV), once thought to be passed only through blood products. It is now known that hepatitis B can also be transmitted via needle sticks, body piercing and tattooing using un sterilized instruments, the dialysis process, sexual and even less intimate close contact, and childbirth. Symptoms include fatigue, jaundice, nausea, vomiting, dark urine, light stools. Diagnosis is by blood test. Treatment is via anti-viral drugs and/or hepatitis B immunoglobulin (HBIG).
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Hepatocellular carcinoma: A tumor in which the cancer starts during adulthood in cells in the liver. Also called adult primary liver cancer.
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Herbal: 1. An adjective, referring to herbs, as in an herbal tea.
2. A noun, usually reflecting the botanical or medicinal aspects of herbs; also a book which catalogs and illustrates herbs.
The word "herbal" was pronounced with a silent "h" on both sides of the Atlantic until the 19th century but this usage persists only on the American side.

Immune: Protected against infection. The Latin immunis means free, exempt.

Immune system: A complex system that is responsible for distinguishing us from everything foreign to us, and for protecting us against infections and foreign substances. The immune system works to seek and kill invaders.
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Immunity: The condition of being immune. Immunity can be innate (for example, humans are innately immune to canine distemper) or conferred by a previous infection or immunization.

Indicate: In medicine, to make a treatment or procedure advisable because of a particular condition or circumstance. For example, certain medications are indicated for the treatment of hypertension during pregnancy while others are contraindicated.

Infection: The growth of a parasitic organism within the body. (A parasitic organism is one that lives on or in another organism and draws its nourishment therefrom.) A person with an infection has another organism (a "germ") growing within him, drawing its nourishment from the person.
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Inflammation: A basic way in which the body reacts to infection, irritation or other injury, the key feature being redness, warmth, swelling and pain. Inflammation is now recognized as a type of nonspecific immune response.
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Inflammatory bowel disease: A group of chronic intestinal diseases characterized by inflammation of the bowel -- the large or small intestine. The most common types of inflammatory bowel disease (IBD) are ulcerative colitis and Crohn disease.
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Injury: Harm or hurt. The term "injury" may be applied in medicine to damage inflicted upon oneself as in a hamstring injury or by an external agent on as in a cold injury. The injury may be accidental or deliberate, as with a needlestick injury. The term "injury" may be synonymous (depending on the context) with a wound or with trauma.

Iron: An essential mineral. Iron is necessary for the transport of oxygen (via hemoglobin in red blood cells) and for oxidation by cells (via cytochrome). Deficiency of iron is a common cause of anemia. Food sources of iron include meat, poultry, eggs, vegetables and cereals (especially those fortified with iron). According to the National Academy of Sciences, the Recommended Dietary Allowances of iron are 15 milligrams per day for women and 10 milligrams per day for men. Iron overload can damage the heart, liver, gonads and other organs. Iron overload is a particular risk in people who may have certain genetic conditions (hemochromatosis) sometimes without knowing it and also in people receiving recurrent blood transfusions. Iron supplements meant for adults (such as pregnant women) are a major cause of poisoning in children.

Itching: An uncomfortable sensation in the skin that feels as if something is crawling on the skin or in the skin, and makes the person want to scratch the affected area.
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Jaundice: Yellow staining of the skin and sclerae (the whites of the eyes) by abnormally high blood levels of the bile pigment bilirubin. The yellowing extends to other tissues and body fluids. Jaundice was once called the "morbus regius" (the regal disease) in the belief that only the touch of a king could cure it.
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Kidney: One of a pair of organs located in the right and left side of the abdomen which clear "poisons" from the blood, regulate acid concentration and maintain water balance in the body by excreting urine. The kidneys are part of the urinary tract. The urine then passes through connecting tubes called "ureters" into the bladder. The bladder stores the urine until it is released during urination.

Laboratory: A place for doing tests and research procedures and preparing chemicals, etc. Although "laboratory" looks very like the Latin "laboratorium" (a place to labor, a work place), the word "laboratory" came from the Latin "elaborare" (to work out, as a problem, and with great pains), as evidenced by the Old English spelling "elaboratory" designating "a place where learned effort was applied to the solution of scientific problems."

Lactate dehydrogenase: (LDH) An enzyme that catalyzes the conversion of lactate to pyruvate. This is an important step in energy production in cells. Many different types of cells in the body contain this enzyme. Some of the organs relatively rich in LDH are the heart, kidney, liver, and muscle.
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LDH: Lactate dehydrogenase.

Lipitor: See: Atorvastatin.

Liter: A metric measure of capacity that, by definition, is equal to the volume of a kilogram of water at 4 degrees centigrade and at standard atmospheric pressure of 760 millimeters of mercury.

• Metric equivalents -- There are 1000 cubic centimeters or 1 cubic decimeter in 1 liter.
• U.S. equivalent -- A liter is a little more than a quart (1.057 U.S. liquid quarts).

Liver: An organ in the upper abdomen that aids in digestion and removes waste products and worn-out cells from the blood. The liver is the largest solid organ in the body. The liver weighs about three and a half pounds (1.6 kilograms). It measures about 8 inches (20 cm) horizontally (across) and 6.5 inches (17 cm) vertically (down) and is 4.5 inches (12 cm) thick.

Liver disease: Liver disease refers to any disorder of the liver. The liver is a large organ in the upper right abdomen that aids in digestion and removes waste products from the blood.
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Malaise: A vague feeling of discomfort, one that cannot be pinned down but is often sensed as "just not right."
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Medical history: 1. In clinical medicine, the patient's past and present which may contain clues bearing on their health past, present, and future. The medical history, being an account of all medical events and problems a person has experienced, including psychiatric illness, is especially helpful when a differential diagnosis is needed.
2. The history of medicine.

Metabolic: Relating to metabolism, the whole range of biochemical processes that occur within us (or any living organism). Metabolism consists of anabolism (the buildup of substances) and catabolism (the breakdown of substances).
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Molecule: The smallest unit of a substance that can exist alone and retain the character of that substance.

MPH: Master of Public Health (a master's degree in this field of medicine).

Naprosyn: See: Naproxen.

Naproxen: A non-steroidal anti-inflammatory drug (NSAID) used for the management of mild to moderate pain, fever, and inflammation. Naproxen blocks the enzyme cyclooxygenase that makes prostaglandins, resulting in lower concentrations of prostaglandins. As a consequence, inflammation, pain and fever are reduced. Brand names for naproxen include Anaprox, Naprelan, Naprosyn, and Aleve.
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Nausea: Nausea, is the urge to vomit. It can be brought by many causes including, systemic illnesses, such as influenza, medications, pain, and inner ear disease. When nausea and/or vomiting are persistent, or when they are accompanied by other severe symptoms such as abdominal pain, jaundice, fever, or bleeding, a physician should be consulted.

Normal range: By convention, the normal range for whatever (a particular test, condition, symptom, behavior, etc.) is set to cover ninety-five percent (95%) of all values from the general population. Five percent (5%) of results consequently fall outside the normal range. Values that prove normal can therefore sometimes be outside the normal range.
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Obesity: The state of being well above one's normal weight.
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Obstruction: Blockage of a passageway. See, for example: Airway obstruction; Intestinal obstruction.

Organ: A relatively independent part of the body that carries out one or more special functions. The organs of the human body include the eye, ear, heart, lungs, and liver.

Pain: An unpleasant sensation that can range from mild, localized discomfort to agony. Pain has both physical and emotional components. The physical part of pain results from nerve stimulation. Pain may be contained to a discrete area, as in an injury, or it can be more diffuse, as in disorders like fibromyalgia. Pain is mediated by specific nerve fibers that carry the pain impulses to the brain where their conscious appreciation may be modified by many factors.
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Poisoning: Taking a substance that is injurious to health or can cause death. Poisoning is still a major hazard to children, despite child-resistant (and sometimes adult-resistant) packaging and dose-limits per container.
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Pregnancy: The state of carrying a developing embryo or fetus within the female body. This condition can be indicated by positive results on an over-the-counter urine test, and confirmed through a blood test, ultrasound, detection of fetal heartbeat, or an X-ray. Pregnancy lasts for about nine months, measured from the date of the woman's last menstrual period (LMP). It is conventionally divided into three trimesters, each roughly three months long.
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Proteins: Large molecules composed of one or more chains of amino acids in a specific order determined by the base sequence of nucleotides in the DNA coding for the protein.
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Psychiatric: Pertaining to or within the purview of psychiatry, the medical specialty concerned with the prevention, diagnosis, and treatment of mental illness.
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Seizure: Uncontrolled electrical activity in the brain, which may produce a physical convulsion, minor physical signs, thought disturbances, or a combination of symptoms.
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Serum: The clear liquid that can be separated from clotted blood. Serum differs from plasma, the liquid portion of normal unclotted blood containing the red and white cells and platelets. It is the clot that makes the difference between serum and plasma.
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SGPT: Serum glutamic pyruvic transaminase, an enzyme that is normally present in liver and heart cells. SGPT is released into blood when the liver or heart are damaged. The blood SGPT levels are thus elevated with liver damage (for example, from viral hepatitis) or with an insult to the heart (for example, from a heart attack). Some medications can also raise SGPT levels. Also called alanine aminotransferase (ALT).

Shock: In medicine, shock is a critical condition brought on by a sudden drop in blood flow through the body. There is failure of the circulatory system to maintain adequate blood flow. This sharply curtails the delivery of oxygen and nutrients to vital organs. It also compromises the kidney and so curtails the removal of wastes from the body. Shock can be due to a number of different mechanisms including not enough blood volume (hypovolemic shock) and not enough output of blood by the heart (cardiogenic shock). The signs and symptoms of shock include low blood pressure (hypotension), overbreathing (hyperventilation), a weak rapid pulse, cold clammy grayish-bluish (cyanotic) skin, decreased urine flow (oliguria), and mental changes (a sense of great anxiety and foreboding, confusion and, sometimes, combativeness).
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Steatohepatitis: Fatty inflammation of the liver, usually in alcoholics. Steato- refers to fat and -hepatitis to inflammation of the liver.

Sulfonamides: The sulfa-related group of antibiotics, which are used to treat bacterial infection and some fungal infections.
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Therapy: The treatment of disease.
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Transfusion: The transfer of blood or blood products from one person (the donor) into another person (the recipient's) bloodstream. In most situations, this is done as a lifesaving maneuver to replace blood cells or blood products lost through severe bleeding. Transfusion of your own blood (autologous) is the safest method but requires planning ahead and not all patients are eligible. Directed donor blood allows the patient to receive blood from known donors. Volunteer donor blood is usually most readily available and, when properly tested has a low incidence of adverse events.
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Tuberculosis: A highly contagious infection caused by the bacterium called Mycobacterium tuberculosis. Abbreviated TB. Tubercles (tiny lumps) are a characteristic finding in TB. Diagnosis may be made by skin test, which if positive should will be followed by a chest X-ray to determine the status (active or dormant) of the infection. Tuberculosis is more common in people with immune system problems, such as AIDS, than in the general population. Treatment of active tuberculosis is mandatory by law in the US, and should be available at no cost to the patient through the public health system. It involves a course of antibiotics and vitamins that lasts about six months. It is important to finish the entire treatment, both to prevent reoccurrence and to prevent the development of antibiotic-resistant tuberculosis. Most patients with tuberculosis do not need to be quarantined, but it is sometimes necessary.
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Tubes: The "tubes" are medically known as the Fallopian tubes. There are two Fallopian tubes, one on each side, which transport the egg from the ovary to the uterus (the womb). The Fallopian tubes have small hair-like projections called cilia on the cells of the lining.
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Tylenol: See: Acetaminophen.

Ulcerative colitis: A relatively common disease that causes inflammation of the large intestine (the colon). The cause is unknown.
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Ultrasound: High-frequency sound waves. Ultrasound waves can be bounced off of tissues using special devices. The echoes are then converted into a picture called a sonogram. Ultrasound imaging, referred to as ultrasonography, allows physicians and patients to get an inside view of soft tissues and body cavities, without using invasive techniques. Ultrasound is often used to examine a fetus during pregnancy. There is no convincing evidence for any danger from ultrasound during pregnancy.

Vaccination: Injection of a killed microbe in order to stimulate the immune system against the microbe, thereby preventing disease. Vaccinations, or immunizations, work by stimulating the immune system, the natural disease-fighting system of the body. The healthy immune system is able to recognize invading bacteria and viruses and produce substances (antibodies) to destroy or disable them. Immunizations prepare the immune system to ward off a disease. To immunize against viral diseases, the virus used in the vaccine has been weakened or killed. To only immunize against bacterial diseases, it is generally possible to use a small portion of the dead bacteria to stimulate the formation of antibodies against the whole bacteria. In addition to the initial immunization process, it has been found that the effectiveness of immunizations can be improved by periodic repeat injections or "boosters." Also see Vaccines (in the plural) and Vaccine of a specific type (such Vaccine, Polio).

Viral: Of or pertaining to a virus. For example, "My daughter has a viral rash."

Viral hepatitis: Viral hepatitis is liver inflammation caused by viruses. Specific hepatitis viruses have been labeled A, B, C, D, E, F, and G. While other viruses can also cause hepatitis, their primary target is not the liver.

Viruses: Small living particles that can infect cells and change how the cells function. Infection with a virus can cause a person to develop symptoms. The disease and symptoms that are caused depend on the type of virus and the type of cells that are infected.