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Gait - pattern of walking or locomotion.
galactose - a type of sugar in milk products and sugar beets, also produced within the body.
Galactosemia - an inherited condition in which galactose builds up in the body, caused by a lack of one of the enzymes needed to breakdown galactose into glucose.
Gallbladder - organ that stores the bile made in the liver and sends bile into the small intestine to help digest fat.
Gallstones - solid masses or stones made of cholesterol or bilirubin that form in the gallbladder or bile ducts.
Gamma camera - a device used in nuclear medicine to scan patients who have been injected with small amounts of radioactive materials.
Ganglion - a cluster of nerve cells.
Ganglion cysts - noncancerous, fluid-filled cysts that are common masses or lumps in the hand; usually found on the back of the wrist.
Gangrene - a death of body tissue that usually occurs when there has been an interruption of blood supply, followed by bacterial invasion.
Gardner syndrome - a rare genetic condition in which many polyps form throughout the digestive tract. A person affected with Gardner syndrome may also have more than the normal number of teeth, bony tumors in the skull, and/or skin cysts or tumors.
Gas - air that comes from the normal breakdown of food and is passed out of the body through the rectum (flatus) or the mouth (belch).
Gastrectomy - complete or partial removal of the stomach.
Gastric - related to the stomach.
Gastric juices - liquids produced in the stomach to help break down food and kill bacteria.
Gastric resection - operation to remove part or all of the stomach.
Gastric ulcer (also called stomach ulcer) - open sore in the stomach lining.
Gastrin - a hormone released in the stomach after eating, which causes the stomach to produce more acid.
Gastritis - inflammation of the stomach lining.
Gastrocolic reflex - increase of muscle movement in the gastrointestinal tract when food enters an empty stomach, which may cause the urge to have a bowel movement right after eating.
Gastroenteritis - infection or irritation of the stomach and intestines, which may be caused by bacteria, viruses, or parasites from spoiled food or unclean water.
Gastroenterologist - physician who specializes in digestive diseases.
Gastroenterology - field of medicine concerned with the function and disorders of the digestive system.
Gastroesophageal reflux disease (GERD) - a digestive disorder that is caused by gastric acid flowing from the stomach into the esophagus.
Gastroparesis (also called delayed gastric emptying) - a condition in which the stomach's ability to empty its contents into the small intestine is decreased, but no obstruction exists. This causes slow digestion and emptying, vomiting, nausea, or bloating.
Gastroscopy - examining the lining of the esophagus, stomach, and the first part of the small intestine with a long viewing tube.
Gastrostomy - an opening created from the stomach to a hole (stoma) in the abdomen where a feeding tube is inserted.
Gastrostomy tube - a type of feeding tube that is inserted into the stomach if the patient is unable to take food by mouth.
Gated blood pool scan - a nuclear scan used to assess how well the heart wall moves and how much blood is expelled with each heartbeat.
General anesthetic - an anesthetic which causes the patient to become unconscious during surgery.
Generalized anxiety disorder (GAD) - a mental disorder that causes its sufferers chronic and exaggerated worry and tension that seem to have no substantial cause. People with generalized anxiety disorder often worry excessively about health, money, family, or work, and continually anticipate disaster.
Genes - basic, functional units of heredity, each occupying a specific place on a chromosome.
Genetic counseling - providing information, advice, and testing to a person who has a genetic condition in his or her family, such as to prospective parents at risk of having a child with a birth defect or genetic disorder.
Genetics - the study of how traits and diseases are inherited from one generation to the next.
Genital herpes - a sexually transmitted disease (STD) caused by the herpes simplex virus.
Genital warts (also called venereal warts or condylomata acuminata) - an STD caused by a virus related to the virus that causes common skin warts. Usually, genital warts first appear as small, hard, painless bumps in the vaginal area, on the penis, or around the anus.
Genitals - external sex organs.
Genu valgum - commonly known as "knock knees."
Genu varum - commonly known as "bowed legs."
Gestational diabetes - form of diabetes which begins during pregnancy in women who have not been known to have diabetes before, and usually disappears following delivery.
Giant cell arteritis (also called cranial arteritis, temporal arteritis, or Horton's disease) - a disease that causes inflammation of the temporal arteries and other arteries in the head and neck, causing the arteries to narrow, reducing blood flow in the affected areas; may cause persistent headaches and vision loss.
Giardiasis - an infectious, diarrheal disease caused by the parasite Giardia lamblia, which can be transmitted through oral-fecal contact and by water contaminated by feces.
GIFT (gamete intrafallopian transfer) - method of treating infertility by removing eggs from a woman's ovaries, combining them with sperm from her partner or a donor in the laboratory, and placing the eggs and sperm together in one of her fallopian tubes, where fertilization can occur.
Glaucoma - a condition in the eye in which increased intraocular (inside the eye) pressure occurs that can result in optic nerve damage and loss of sight.
Glomerulonephritis - a type of glomerular kidney disease in which the kidneys' filters become inflamed and scarred, and slowly lose their ability to remove wastes and excess fluid from the blood to make urine.
Glomerulosclerosis - the term used to describe scarring that occurs within the kidneys in the small balls of tiny blood vessels called the glomeruli. The glomeruli assist the kidneys in filtering urine from the blood.
Glucagon - a protein hormone secreted by the pancreas to stimulate the liver to produce glucose.
Glucose - a simple sugar, which is the body's main source of energy.
Glucose tolerance test - blood test used to make the diagnosis of diabetes, including gestational diabetes.
Glucose-6-phosphate dehydrogenase deficiency (G6PD) - an inherited disease in which a deficiency of the enzyme G6PD affects red blood cells and can cause hemolytic anemia.
Gluten - a protein found in wheat, rye, barley, and oats.
Gluten sensitive enteropathy (also called celiac sprue or celiac disease) - a sensitivity to gluten, a wheat protein. Individuals with this disease must avoid gluten-containing grains, which include all forms of wheat, oats, barley, and rye.
Gluteus maximus - large, superficial, buttock muscle.
Glycogen - converted glucose for storage. Glycogen plays a role in controlling blood sugar levels.
Goiter - an overgrown thyroid gland.
Gonads - ovaries and testes.
Gonadotropins - luteinizing hormone and follicle-stimulating hormone, produced by the pituitary gland.
Gonorrhea - a common sexually transmitted disease caused by a bacterium, which can lead to infertility in women.
Goodpasture syndrome - a rare autoimmune disease that can affect the lungs and kidneys.
Gout - a form of arthritis that occurs as a result of a buildup of uric acid in a joint. This painful condition most often attacks small joints, especially the big toe. It can usually be controlled with medication and changes in diet.
Grade - the grade of a cancer reflects how abnormal it looks under the microscope. There are several grading systems for different types of cancer.
grades of movement - standardized means of documenting techniques of mobilization, relating it to the true feel of joint movement.
Grading - a process for classifying cancer cells to determine the growth rate of the tumor. The cancer cells are measured by how closely they look like normal cells.
Graft-versus-host disease (GVHD) - a condition that occurs when the donor's immune system acts against the recipient's tissue after stem cell or bone marrow transplantation.
Granulocytes - a type of white blood cell. The different types of granulocytes include: basophils, eosinophils, and neutrophils.
Granuloma annulare - a chronic skin condition characterized by small, raised bumps that form a ring with a normal or sunken center.
Gray matter - the darker-colored tissues of the central nervous system; in the brain, the gray matter includes the cerebral cortex, thalamus, basal ganglia, and outer layers of the cerebellum.
Guided imagery - envisioning a certain goal to help cope with health problems.
Guillain-Barré syndrome - a disorder in which the body's immune system attacks part of the nervous system, leading to progressive weakness in the legs, arms, and upper body.
Gulf War syndrome - a term that refers to unexplained illnesses occurring in Gulf War veterans. Some of the illnesses that have affected veterans of the Gulf War include chronic fatigue syndrome, fibromyalgia, and irritable bowel syndrome, as well as certain signs and symptoms not associated with a specific disease, such as abnormal weight loss, joint pain, headaches, and sleep disturbances.
Gustation - act or sensation of tasting.
Gynecomastia - a condition in which the male's breast tissue enlarges. Gynecomastia literally means "woman breast." This increase in tissue usually occurs at times when the male is having hormonal changes, such as during infancy, adolescence, and old age.