|
| | |
Endoplasmic reticulum
Endoplasmic reticulum A network or system of folded membranes and interconnecting tubules distributed within the cytoplasm of eukaryotic cells. The membranes form enclosed or semienclosed spaces. The endoplasmic reticulum functions in storage and transport, and as a point of attachment of ribosomes during protein synthesis.
RELATED TERMS--------------------------------------
Membranes
Also know as the bag of waters, this thin sac contains the amniotic fluid and the fetus. The membranes will either rupture spontaneously during labor or be ruptured to speed up labor.
Cytoplasm
The living matter within a cell (excluding the nucleus) that is responsible for the function of the cell (for example, protein synthesis).
Eukaryotic
The living world is divided into two classes of organism. Eukaryotic and, much simpler, prokaryotic organisms such as bacteria. Generally eukaryotes are diploid and their cells have internal organelles, such as nuclei. Prokaryotes are haploid with much simpler cells.
Protein
Any of a group of complex organic compounds which contain carbon, hydrogen, oxygen, nitrogen, and usually sulfur, the characteristic element being nitrogen. Proteins, the principal constituents of the protoplasm of all cells, are of high molecular weight and consist essentially of combinations of a-amino acids in peptide linkages. Twenty different amino acids are commonly found in proteins, and each protein has a unique genetically defined amino acid sequence which determines its specific shape and function. Their roles include enzymatic catalysis, transport and storage, coordinated motion, nerve impulse generation and many others.
SIMILAR TERMS--------------------------------------
Endocannabinoid
A marijuana-like substance. Endocannabinoid is abbreviated EC.
Endocardial
Pertaining to the endocardium, the inside lining of the heart.
Endocarditis
A bacterial infection of the heart lining.
Endocarditis (SBE)
An infection of the inner lining of the heart or its valves. It is usually caused by bacteria and is more likely to occur in people who have heart valve defects or have had heart surgery to treat valve disease.
Endocardium
The membrane that covers the inside surface of the heart.
Endocervical curettage
The removal of tissue from the inside of the cervix using a spoon-shaped instrument called a curette.
Endochondral bone
Any bone that develops in and replaces cartilage. The cartilage is partially or entirely destroyed by the process of calcification. The cartilage is then resorbed (reabsorbed), leaving bone in its place. Many bones are formed this way, particularly the long bones of the arms, legs, and ribs.
Endocrine
Pertaining to hormones and the glands that make and secrete them into the bloodstream through which they travel to affect distant organs. The endocrine sites include the hypothalamus, pituitary gland, pineal gland, thyroid, parathyroids, heart (which makes atrial-natriuretic peptide), the stomach and intestines, islets of Langerhans in the pancreas, the adrenal glands, the kidney (which makes renin, erythropoietin, and calcitriol), fat cells (which make leptin). the testes, the ovarian follicle (estrogens) and the corpus luteum in the ovary). Endocrine is as opposed to exocrine. (The exocrine glands include the salivary glands, sweat glands and glands within the gastrointestinal tract.)
Endocrine gland
One of the body's ductless glands from which a hormone is secreted directly into the bloodstream.
Endocrine glands
Glands that are ductless and release their secretions directly into the bloodstream.
Endocrine Glands
Glands that release hormones into the bloodstream. They affect how the body uses food (metabolism). They also influence other body functions. One endocrine gland is the pancreas. It releases insulin so the body can use sugar for energy.
Endocrine hormones
Hormones that are secreted from a discrete gland and then travel through the bloodstream to target tissues.
Endocrine pancreas
The part of the pancreas that produces hormones that govern sugar metabolism. Compare with the exocrine pancreas.
Endocrinologist
A physician trained in diagnosing and treating disorders of hormone-secreting (endocrine) organs. These organs include the thyroid, parathyroid and adrenal glands, the pituitary, the pineal body and the gonads.
Endocrinology
The study of hormones. A more inclusive definition would be the study of biological communications.
Endocrinopathy
Literally, a disease of an endocrine gland. A medical term for a hormone problem. For example, hyperthyroidism, hypothyroidism, etc.
Endocytosis
The process by which extracellular molecules (including hormones) enter a cell.
Endoderm
One of the three primary germ cell layers -- the other two are the mesoderm and ectoderm -- in the very early embryo. The endoderm is the innermost of the three layers. It differentiates to give rise first to the embryonic gut and then to the linings of respiratory and digestive tracts and the liver and pancreas.
Endodermal
Pertaining to the endoderm or to tissues derived from the endoderm.
Endodontist
Specialist who treats injuries, diseases and infections of the tooth pulp (nerve chamber).
Endogenous
Produced from within.
Endometrial ablation
Removal of the lining of the womb. Removing the uterine lining decreases menstrual flow or stops it completely. Ablation means removal or excision, usually surgically. The word comes from the Latin ablatum meaning to carry away.
Endometrial cancer
Cancer of the womb (the uterus ). Endometrial cancer occurs most often in women between the ages of 55 and 70 years. It accounts for about 6% of cancer in women. Women at elevated risk for endometrial cancer include those who are obese, who have few or no children, who began menstruating at a young age, who had a late menopause, and women of high socioeconomic status. It is thought that most of these risk factors are related to hormones, especially excess estrogen.
Endometrial hyperplasia
Abnormal thickening of the endometrium caused by excessive cell growth.
Endometrial implants
Fragments of endometrium that relocate outside of the uterus, such as in the muscular wall of the uterus, ovaries, fallopian tubes, vagina, or intestine, and bleed monthly just as endometrium does in the uterus.
Endometriosis
A condition in which tissue more or less perfectly resembling the uterine mucous membrane (the endometrium) and containing typical endometrial granular and stromal elements occurs aberrantly in various locations in the pelvic cavity.
Endometriosis interna
Also known as adenomyosis this is a common benign condition of the uterus in which the endometrium (the mucous membrane lining the inside of the uterus) grows into the myometrium (the uterine musculature located just outside the endometrium). The endometrium and myometrium under normal circumstances live adjacent to one another as discrete neighbors. In adenomyosis, the endometrium trespasses upon the myometrium. The myometrium may respond to this intrusion with muscular overgrowth.
Endometriosis uterina
Also known as adenomyosis, this is a common benign condition of the uterus in which the endometrium (the mucous membrane lining the inside of the uterus) grows into the myometrium (the uterine musculature located just outside the endometrium). The endometrium and myometrium under normal circumstances live adjacent to one another as discrete neighbors. In adenomyosis, the endometrium trespasses upon the myometrium. The myometrium may respond to this intrusion with muscular overgrowth.
Endometritis
Inflammation of the endometrium. The endometrium is the inner layer of the womb (uterus).
Endometrium
The lining of the uterus or womb. Structurally, it is a mucous membrane.
Endonuclease
An enzyme that cleaves a nucleic acid (DNA or RNA) at specific internal sites in the nucleotide base sequence.
Endopeptidase
An enzyme that catalyzes the cleavage of peptide bonds within a polypeptide or protein. Peptidase refers to the fact that it acts on peptide bonds and endopeptidase refers to the fact that these are internal bonds. An exopeptide catalyzes the cleavage of the terminal or penultimate peptide bond, releasing a single amino acid or dipeptide from the peptide chain.
Endophthalmitis
An inflammation involving the internal parts of the eye – i.e., choroid, retina, ciliary body and iris. A very serious condition sometimes seen after an injury to the eye by a foreign object. Vision is severely threatened. Large doses of cortisone and antibiotics are often needed. May lead to the removal of the eye. Must be treated by an eye doctor ASAP.
Endorectal MRI
An MRI (magnetic resonance imaging) done from inside the rectum. To do such as MRI, a surface coil within an inflated latex balloon can be positioned in the rectum. The MRI is read (interpreted) and specific areas of suspicion are identified. The MRI data can be mapped onto a 3-dimensional model to determine strategy.
Endorphins
The general term to refer to all of the body's own endogenous morphinelike substances. In chemical structure, they are neuropeptides. They are active as neurotransmitters and neuromodulators.
Endoscope
A small, flexible tube with a light and a lens on the end. It is used to look into the esophagus, stomach, duodenum, colon, or rectum. It can also be used to take tissue from the body for testing or to take color photographs of the inside of the body. Colonoscopes and sigmoidoscopes are types of endoscopes.
Endoscopic gastrostomy, percutaneous (PEG)
A surgical procedure for placing a feeding tube without having to perform an open laparotomy (operation on the abdomen). The aim of PEG is to feed those who cannot swallow. PEG may be done by a surgeon, otolaryngologist (ENT specialist), or gastroenterologist (GI specialist). It is done in a hospital or outpatient surgical facility. Local anesthesia (usually lidocaine or another spray) is used to anesthetize the throat. An endoscope (a flexible, lighted instrument) is passed through the mouth, throat and esophagus to the stomach. The surgeon then makes a small incision (cut) in the skin of the abdomen and pushes an intravenous cannula (an IV tube) through the skin into the stomach and sutures (ties) it in place. The patient can usually go home the same day or the next morning. Possible complications include wound infection (as in any kind of surgery) and dislodging or malfunction of the tube. Percutaneous endoscopic gastrostomy may be a mouthful (as a term) but it describes the procedure accurately. A gastrostomy (a surgical opening into the stomach) is made percutaneously (through the skin) using an endoscope to put the feeding tube in place. PEG takes less time, carries less risk and costs less than a classic surgical gastrostomy which requires opening the abdomen.
Endoscopic papillotomy
An operation to cut the muscle between the common bile duct and the pancreatic duct. The operation uses a catheter and a wire to remove gallstones or other blockages. Also called endoscopic sphincterotomy.
Endoscopic retrograde cholangiopancreatography
Abbreviated ERCP. A procedure done to diagnose and treat problems in the liver, gallbladder, bile ducts, and pancreas, including gallstones, inflammatory strictures (scars), leaks (from trauma and surgery), and cancer. ERCP combines the use of x-rays and an endoscope (a long, flexible, lighted tube). Through it, the physician can see the inside of the stomach and duodenum and inject dye into the bile ducts and pancreas so they can be seen on x-ray. ERCP takes 30 minutes to 2 hours. Possible complications of ERCP include pancreatitis (inflammation of the pancreas), infection, bleeding, and perforation of the duodenum.
Endoscopic retrograde cholangiopancreatography (ERCP)
A test using an x-ray to look into the bile and pancreatic ducts. The doctor inserts an endoscope through the mouth into the duodenum and bile ducts. Dye is sent through the tube into the ducts. The dye makes the ducts show up on an x-ray.
Endoscopic sphincterotomy
An operation to cut the muscle between the common bile duct and the pancreatic duct. The operation uses a catheter and a wire to remove gallstones or other blockages. Also called endoscopic papillotomy.
Endoscopic ultrasound
Abbreviated EUS. A procedure that combines endoscopy and ultrasound to obtain images and information about the digestive tract and the surrounding tissue and organs. In EUS a small ultrasound transducer is installed on the tip of the endoscope allowing the transducer to get close to the organs inside the body so the resultant ultrasound images are often more accurate and detailed than ones obtained by traditional ultrasound.
Endoscopy
Procedure in which a lighted viewing instrument (endoscope) is used to look inside a body cavity or organ to diagnose or treat disorders.
Endoscopy, upper
A common type of endoscopy is upper endoscopy, also called esophagogastroduodenoscopy (EGD). In this procedure, a thin flexible instrument is advanced through the mouth to evaluate or treat problems of the esophagus, stomach, and beginning part of the small intestine. Endoscopy itself is a broad term used to described examining the inside of the body using an lighted, flexible instrument called an endoscope. In general, an endoscope is introduced into the body through a natural opening such as the mouth in the case of upper endoscopy.
Endosol extra
Endosol extra is a prescription or over-the-counter drug which is (or once was) approved in the United States and possibly in other countries. Active ingredient(s): calcium chloride; dextrose; glutathione disulfide; magnesium chloride; potassium chloride; sodium bicarbonate; sodium chloride; sodium phosphate.
Endostatin
Endostatin is a piece (a fragment) of a protein, collagen 18, found in all blood vessels. This fragment is normally secreted by tumors. It appears to halt the process of developing new blood vessels (angiogenesis) which is necessary to tumor development. Endostatin may, it is hoped, represent a prototype for a new class of agents with which to treat cancer.
Endothelial
Relating to the endothelium, the layer of flat cells lining the closed spaces of the body such as the inside of blood vessels, lymphatic vessels, the heart, and body cavities. By contrast, the outside layer of cells that covers all the free, open surfaces of the body including the skin and mucous membranes that communicate with the outside of the body is called the epithelium.
Endothelial cells
The cells that line the vascular system. They act as a barrier between the bloodstream and target cells that hormones must pass through in order to reach their receptors and exert their biological action.
Endothelial progenitor cell
A primitive cell made in the bone marrow that can enter the bloodstream and go to areas of blood vessel injury to help repair the damage. The number of endothelial progenitor cells in the blood is a risk factor for vascular disease. Depletion or senescence of endothelial progenitor cells may contribute to blood vessel disease.
Endothelium
The interior surfaces of blood vessels. The endothelium, which is the site of atherosclerosis in arteries, is composed of specialized cells called epithelial cells.
Endotherm
An endotherm is a warm-blooded animal (such as homo sapiens). Another term for us warm-blooded creatures is homeotherm. An endotherm or homeotherm is as opposed to a poikilotherm (an organism such as a frog that is cold-blooded) and a stenotherm (a creature that can only survive only within a very narrow temperature range).
Endotoxemia
Presence in the blood of endotoxins.
Endotracheal intubation
Passage of a tube through the nose or mouth into the trachea for maintenance of the airway during anesthesia or for maintenance of an imperiled airway.
Endotracheal tube
A tube which is inserted in the airway, by ACLS personnel, to provide a secure airway. This is the definitive airway control technique.
Endourologist
An endourologist is a urologist with special expertise in navigating, using endoscopic optical instruments and other tools, inside the kidney, ureter and bladder. Endourologists are specialists in treating diseases of these organs.
PREVIOUS AND NEXT TERMS--------------------------------------
Epilepsy
Sudden and recurrent disturbances in mental function, state of consciousness, sensory activity, or movements of the body, caused by paroxysmal malfunction of cerebral nerve cells. Epilepsy includes generalized convulsions in which there is sudden unconsciousness with falling and shaking of limbs, momentary lapses of awareness, and local movements and sensations in parts of the body, as well as other types of activity that may include bizarre automatic behaviour, strange memories, illusory and hallucinatory experiences, and changes in mood.
Eating disorders
A group of disorders in which there are significant disturbances in eating. Two common examples are Anorexia Nervosa, a refusal to maintain an acceptable body weight for one’s age and height: and Bulimia Nervosa, uncontrollable binge eating which may be followed by purging the food through self-induced vomiting, laxatives or diuretics.
Emotional disorders
A psychological disorder characterized by maladjustive emotional reactions such as irrational or uncontrollable fears, persistent anxiety, or extreme hostility.
Erythematous
Redness of the skin caused by congestion of the capillaries, often due to inflammation or infection.
Epinephrine
One of two chemicals (the other is norepinephrine) released by the adrenal gland that increases the speed and force of heart beats. It dilates the airways to improve breathing and narrows blood vessels in the skin and intestine so that an increased flow of blood reaches the muscles and allows them to cope with the demands of exercise.
Endoplasmic reticulum
Erythromycin
An antibiotic derived from the bacterium Streptomyces erythreus which is especially effective against gram positive bacteria. This antibiotic is often used to treat people who are allergic to penicillin, to treat penicillin-resistant infections and acne.
Emphysema
Lung disease where the alveoli -parts of the lungs where gas is exchanged- have lost their elasticity. Breathing becomes increasingly difficult, and emphysema patients have to use other muscles to breathe out. The main cause of emphysema is smoking.
Earache
Any ache or pain arising in the ear. Technically it may be called otalgia or otodynia.
Ephedra
Ephedra is a genus of gymnosperm shrubs, the only genus in the family Ephedraceae and order Ephedrales. These plants occur in dry climates over a wide area mainly in the Northern Hemisphere, across southern Europe, north Africa, southwest and central Asia, southwestern North America, and, in the Southern Hemisphere, in South America south to Patagonia. They are also called Joint-pine, Jointfir, yellow horse, country mallow, squaw tea or Mormon Tea. The Chinese species are known as Ma huang.
Ecstasy
Ecstasy, or MDMA (methylenedioxymethamphetamine), is a synthetic drug that acts simultaneously as a stimulant and a hallucinogen. Users sometimes take Ecstasy for the sense of well-being, the sensory distortions caused by the drug, or to stay awake. Ecstasy has been shown to cause brain damage in animals.
We thank you for using the Health Dictionary to search for Endoplasmic reticulum. If you have a better definition for Endoplasmic reticulum than the one presented here, please let us know by making use of the suggest a term option. This definition of Endoplasmic reticulum may be disputed by other professionals. Our attempt is to provide easy definitions on Endoplasmic reticulum and any other medical topic for the public at large.This dictionary contains 25007 terms. |
|
|
