- Health Encyclopedia

The cardiovascular system

Varicose Veins - symptoms, treatment and laser surgery

What is Varicose Veins Varicose Veins are distended and distorted veins, typically occurring in the legs. Varicose veins indicate dysfunctional venous valves, which allow BLOOD to backflow or to pool in the VEIN when standing or sitting (VENOUS INSUFFICIENCY). There appears to be a GENETIC PREDISPOSITION for varicose veins, in that they seem to run in

The Blood and Lymph System

Lymphadenitis definition and symptoms

Lymphadenitis - INFLAMMATION or INFECTION of LYMPH nodes. Lymphadenitis characterizes systemic infections such as infectious mononucleosis and regional infections such as SEXUALLY TRANSMITTED DISEASES (STDS). It may affect any lymph nodes in the body though is most noticeable when it affects LYMPH NODE clusters near the surface of the SKIN, such as in the

Infectious Diseases

Listeriosis and Bacteria Listeria - symptoms and treatment

What is Listeriosis and Bacteria Listeria Listeriosis - an illness that results from INFECTION with the bacterium Listeria monocytogenes. Listeriosis most often occurs as a foodborne illness and has the potential to cause serious symptoms. Listeria monocytogenes are normally present in soil and can contaminate milking equipment. Animals also can carry

Bowel Movement - what is and definition

Bowel Movement - the passage of solid digestive waste (called feces or stool) from the body through the ANUS. The frequency, appearance, and nature of bowel movements are highly variable. Food typically travels through the gastrointestinal system in 18 to 36 hours, so most people have bowel movements daily or every other day. However, “normal”

Aging, cardiovascular changes that occur with

The most significant age-related changes in cardiovascular function occur at birth in both sexes and with MENOPAUSE in women. Though changes in METABOLISM occur with aging that affect all body systems, researchers now believe cardiovascular health does not inherently decline simply as a function of aging. DIABETES, OBESITY, lack of physical exercise, and

Liver Disease of Alcoholism - symptoms and treatment

Liver Disease of Alcoholism - permanent damage to the LIVER that results from long-term, excessive ALCOHOL consumption. Alcohol is one of the most toxic substances ingested into the body. It enters the bloodstream unchanged, about 20 percent absorbed from the STOMACH and 80 percent from the SMALL INTESTINE. The liver must filter alcohol from the blood, a

Phagocytosis definition

What is Phagocytosis and Definition Phagocytosis - the process through which a PHAGOCYTE (a specialized LEUKOCYTE) consumes a PATHOGEN or other cellular particle. Phagocytosis is a key defense mechanism of the body’s IMMUNE RESPONSE and may take place in the BLOOD, primarily the domain of granulocytes (neutrophils and eosinophils), and in the

Myasthenia Gravis - symptoms and treatment

Myasthenia Gravis is a rare autoimmune disorder in which the IMMUNE SYSTEM produces antibodies that target acetylcholine receptors on the cell membrane surfaces of MUSCLE cells. Acetylcholine is a NEUROTRANSMITTER that carries NERVE impulses from neurons to muscle cells to initiate movement. Acetylcholine receptors are specialized molecules that bind

Erythrocyte definition

What is Erythrocyte and Definition A red BLOOD cell (RBC). The primary function of erythrocytes is to carry oxygen from the LUNGS to the cells of tissues throughout the body and return carbon dioxide, a metabolic waste, to the lungs for removal from the body. Erythrocytes contain iron and HEMOGLOBIN, a pigmented protein that gives them their red color.

Jejunum - function and definition

Jejunum is the middle segment of the SMALL INTESTINE, between the ILEUM and the DUODENUM. The jejunum is six to eight feet long and handles absorption of carbohydrates and proteins, as well as vitamins such as VITAMIN K and minerals such as iron. The jejunum’s tissue composition and excellent blood supply allow it to be the source of tissue grafts for

Antacids - medications - information and side effects

Antacids are products that neutralize gastric (STOMACH) acid to relieve DYSPEPSIA (heartburn and indigestion). Antacids work by increasing the pH (acid level) of the gastric juices, which reduces the irritation to the stomach tissues. Most antacids contain mineral salts, which are alkaline. Because of their high salt and mineral content, many antacids can

Helicobacter Pylori bacteria - symptoms and treatment

Helicobacter Pylori - the BACTERIA responsible for much PEPTIC ULCER DISEASE and STOMACH CANCER. Researchers isolated H. pylori in 1982, a discovery that dramatically altered the treatment approach to ulcers. Though researchers do not know how Helicobacter Pylori enter the gastrointestinal system, they believe INFECTION occurs early in life in most people.

Strabismus (tropia) - causes, treatment and surgery

Strabismus (tropia) is a condition, also called tropia, in which the eyes do not focus simultaneously on the same object. One EYE may turn inward (“crosseye” or esotropia), or one eye may turn outward (“walleye” or exotropia). Congenital strabismus may occur with RETINOBLASTOMA or RETINOPATHY of prematurity and becomes apparent in

Gastroenteritis - viral, bacteria, parasite - symptoms and treatment

Gastroenteritis is INFLAMMATION of the SMALL INTESTINE. The most common cause of gastroenteritis is viral INFECTION, though sometimes BACTERIA or PARASITES are responsible. The inflammation of the intestinal mucosa (mucus lining of the intestinal wall) reduces the small intestine’s ability to absorb NUTRIENTS and fluid. People often refer to

Gastroesophageal Reflux Disorder (GERD) - Symptoms and Treatment

Gastroesophageal Reflux Disorder (GERD) - a chronic condition in which gastric contents leak back from the STOMACH into the ESOPHAGUS. Because stomach juices are highly acidic, this backwash creates chemical BURNS in the delicate tissues of the esophagus. The lining of the esophagus lacks the protective mucus that safeguards the stomach from gastric acid,

Drug - definition and information

Drug - any product that, when it enters the body, changes the function of the body in some way. Drugs such as ANTIBIOTIC MEDICATIONS work by killing BACTERIA within the body, for example, and antiarrhythmia drugs work by altering the electrical activity of the HEART. As the mainstay of modern medicine, drugs exert therapeutic actions to treat numerous

Amputation procedure - surgery, rehabilitation, complications and risks

What is Amputation Surgery Amputation procedure - Removal or loss of a limb or body part. Amputation may be surgical, in which the removal is intentional to treat a disease condition, or traumatic, in which accidental injury results in the loss of the body part. Most amputations involve digits (fingers and toes) and limbs. In the United States,

Urination - what is, definition, normal urination and normal frequency

What is Urination and Definiton The act of passing URINE from the BLADDER, also called uresis or micturition. Urination occurs when the urethral sphincter relaxes at the same time the detrusor MUSCLE that forms the middle layer of the bladder wall contracts, squeezing urine into the URETHRA. The urethra carries the urine to the meatus, its opening on the

transient ischemic attack (TIA) - symptoms and treatment

What is Transient Ischemic Attack (TIA) A brief, episodic interruption of the flow of BLOOD to the BRAIN, often called a mini-STROKE. The most common cause of a TIA is a fragment of ATHEROSCLEROTIC PLAQUE or a BLOOD clot that breaks free and travels through the blood circulation until it lodges in an ARTERY or arteriole. TIAs also can be hemorrhagic, the

Endoscopy procedure

Endoscopy - the collective term for minimally invasive procedures that allow the doctor to view internal organs and structures using a lighted, flexible scope inserted through a natural body opening or through a small incision. Endoscopy can be diagnostic or therapeutic. Most endoscopic procedures require preparation before the procedure, sedation during

Heart Murmur - symptoms, causes and treatment

What is Heart Murmur and Definition Heart Murmur is the sound of BLOOD flowing through an abnormal opening in the HEART. Heart murmur is a sign rather than a condition. Transient heart murmurs are common and benign, generally signaling an occasional or circumstantial incomplete valve closure, and do not require further evaluation or treatment. Transient

Genome - what is and definition

Genome - the total genetic material, including coding and noncoding sequences, a cell contains in its chromosomes. Each organism has a unique genome. Scientists define the size of a genome by the number of its base pairs. The human genome contains 3.2 billion base pairs, which make up that comprise about 23,000 genes.

Bundle Branch - left and right block

Bundle Branch - An organization of NERVE fibers along the heart’s ventricular septum that conveys electrical impulses to the ventricles to cause them to contract, also called the BUNDLE OF HIS. The right bundle branch extends to the right ventricle and the left bundle branch to the left ventricle. The electrical impulses, which originate with the

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Ornish program - Dean Ornish Diet

The cardiovascular system |

What is Ornish program - Dean Ornish Diet An intensive lifestyle-oriented method for reducing the risk for CORONARY ARTERY DISEASE (CAD) and HEART ATTACK. Named for Dean Ornish, the American physician who developed the approach, the Ornish program features a strict vegetarian diet very low in fat along with daily YOGA, walking, MEDITATION, and

Intraocular Pressure - causes and definition

The Eyes |

Intraocular Pressure - the pressure within the EYE that maintains the eye’s form and structure. Normal intraocular pressure in an adult is 12 to 22 millimeters of mercury (mm Hg). A device called a tonometer measures intraocular pressure, either through light contact against the anesthetized eye or via the force of resistance to a puff of air blown

Prenatal care - what is, first, second and third trimester

The Reproductive System |

What is Prenatal Care and Definition Prenatal Care - Routine and preventive health care provided during PREGNANCY to safeguard the health and well-being of the woman and the FETUS. In the United States routine prenatal care consists of regular visits to the health-care provider (family practitioner, obstetrician, or nurse midwife), URINE and BLOOD tests,

Porphyria - symptoms and treatment

Genetics and Molecular Medicine |

Porphyria - The collective term for a group of eight inherited GENETIC DISORDERS of METABOLISM in which deficiencies of certain enzymes block the production of heme and allow the accumulation of porphyrins. Heme is an iron-containing pigment normally present in nearly all tissues in the body, notably as a component of HEMOGLOBIN in the BLOOD and of electron

Ischemic Heart Disease (IHD) - symptoms and treatment

The cardiovascular system |

What is Ischemic Heart Disease (IHD) Ischemic Heart Disease (IHD) - The consequential condition that results when CORONARY ARTERY DISEASE (CAD) and other conditions that affect the heart’s blood supply deprive the HEART of oxygen over an extended period of time. Ischemia is the medical term for a temporary interruption of BLOOD flow; in ischemic

Nasogastric Aspiration and Lavage - Pumping the Stomach

The Gastrointestinal System |

Nasogastric Aspiration and Lavage - the clinical term for the procedure commonly called “pumping the STOMACH.” In nasogastric aspiration and lavage, the health-care provider inserts a narrow tube (catheter) through the NOSE, down the back of the THROAT and the ESOPHAGUS, and into the stomach. The stomach’s contents are then sucked through

Prosthetic Limb - amr, leg, hand, foot

The Musculoskeletal System |

Prosthetic Limbs - An artificial arm, hand, leg, or foot that provides functional replacement for an amputated or missing limb. A prosthesis represents a balance between function and presentable appearance. Prosthetic limbs available today can provide a very high level of function, allowing many people to return to nearly the same lifestyle as before the

Nephrectomy - procedure, surgery, recovery - definition, risks and complications

The Urinary System |

What is Nephrectomy and Definition A surgical OPERATION to remove a kidney. The most common reasons for nephrectomy are to treat RENAL CANCER, to remove a kidney for live donor KIDNEY TRANSPLANTATION, and to remove a kidney that is severely injured due to trauma or malformed due to CONGENITAL ANOMALY. There are three kinds of nephrectomy: partial

Aneurysm definition and symptoms

The cardiovascular system |

What is Aneurysm and Definition Aneurysm is a weakened and often distended (stretched) area in the wall of an ARTERY. Though an aneurysm may develop in any artery, the most common location is the descending or abdominal AORTA. An aneurysm is potentially life-threatening. The continual pressure of the BLOOD flowing through the artery pressures the weakened

Genetic Screening - what is and definition

Genetics and Molecular Medicine |

Genetic Screening - procedures that indicate whether an individual has the potential to have a genetic disorder. Among the most commonly performed genetic screening procedures in the United States are prenatal ULTRASOUND and maternal BLOOD levels of multiple biomarkers, such as ALPHA FETOPROTEIN (AFP), during PREGNANCY. These procedures may present