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 ). See the entire definition of Abnormal
Achondroplasia : The most common form of short stature with disproportionately short limbs -- dwarfism with short arms and legs. Achondroplasia is caused by mutation in the fibroblast growth factor receptor-3 gene (FGFR3), which is located on chromosome 4 in chromosome band 4p16.3. See the entire definition of Achondroplasia
Amino acid: One of the 20 building blocks of protein . The sequence of amino acids in a protein and, hence, the function of that protein are determined by the genetic code in the DNA . See the entire definition of Amino acid
Amniocentesis : Procedure used in prenatal diagnosis to obtain amniotic fluid which can be used for genetic and other diagnostic tests. Informally called an "amnio." See the entire definition of Amniocentesis
Arginine: An amino acid , one of the 20 amino acids that serve as the building blocks in protein . Arginine is not an "essential" amino acid. It is not essential to the diet, but can be made by the body from other substances. However, it is usually considered essential to the diet for children so they can grow normally. Lack of arginine in the diet impairs growth and in adult males it decreases the sperm count. See the entire definition of Arginine
Arm: 1. In popular usage, the appendage that extends from the shoulder to the hand. However, the medical definition refers to the upper extremity extending from the shoulder only to the elbow, excluding the forearm, which extends from the elbow to the wrist. The arm contains one bone: the humerus. 2. In a randomized clinical trial, any of the treatment groups. Most randomized trials have two "arms," but some have three "arms," or even more.
Arms: An appendage in anatomy and in clinical trials. See: Arm.
Autosomal: Pertaining to a chromosome that is not a sex chromosome; relating to any one of the chromosomes save the sex chromosomes. See the entire definition of Autosomal
Autosomal dominant: A pattern of inheritance in which an affected individual has one copy of a mutant gene and one normal gene on a pair of autosomal chromosomes. (In contrast, autosomal recessive diseases require that the individual have two copies of the mutant gene.) Individuals with autosomal dominant diseases have a 50-50 chance of passing the mutant gene and therefore the disorder onto each of their children. Examples of autosomal dominant diseases include Huntington disease, neurofibromatosis, and polycystic kidney disease.
Bone: Bone is the substance that forms the skeleton of the body. It is composed chiefly of calcium phosphate and calcium carbonate . It also serves as a storage area for calcium, playing a large role in calcium balance in the blood. See the entire definition of Bone
Brain: That part of the central nervous system that is located within the cranium ( skull ). The brain functions as the primary receiver, organizer and distributor of information for the body. It has two (right and left) halves called "hemispheres." See the entire definition of Brain
Brainstem: The lowest part of the brain which merges with the spinal cord and provides the major route by which the upper realms of the brain send information to, and receives information from, the spinal cord and peripheral nerves. The brainstem consists of the medulla oblongata, midbrain, and pons. All but two of the 12 cranial nerves originate in the brainstem. The brainstem influences basic processes such as alertness, breathing, blood pressure, and heart rate.
Breathing: The process of respiration, during which air is inhaled into the lungs through the mouth or nose due to muscle contraction, and then exhaled due to muscle relaxation.
Bridge: A set of one or more false teeth supported by a metal framework, used to replace one or more missing teeth. See the entire definition of Bridge
Cartilage: Firm, rubbery tissue that cushions bones at joints. A more flexible kind of cartilage connects muscles with bones and makes up other parts of the body, such as the larynx and the outside parts of the ears.
Chest: The area of the body located between the neck and the abdomen . The chest contains the lungs , the heart and part of the aorta . The walls of the chest are supported by the dorsal vertebrae , the ribs , and the sternum . See the entire definition of Chest
Chorionic villus sampling: A procedure for first-trimester prenatal diagnosis. Chorionic villus sampling may be done between the eighth and tenth weeks of pregnancy. The aim is to diagnose severe abnormalities afflicting the fetus. In the procedure, tissue is withdrawn from the villi (vascular fingers) of the chorion, a part of the placenta, and examined. Chorionic villus sampling is referred to commonly as CVS. See the entire definition of Chorionic villus sampling
Chromosome: A visible carrier of the genetic information. See the entire definition of Chromosome
Chromosome band: One of the transverse bands produced on chromosomes by differential staining techniques. Depending on the particular staining technique, the bands are alternating light and dark or fluorescent and nonfluorescent. See the entire definition of Chromosome band
Compression: 1. The act of pressing together. As in a compression fracture, nerve compression, or spinal cord compression. 2. To shorten in time. In embryology, there may be compression of development with some stages even omitted.
Conception: 1. The union of the sperm and the ovum. Synonymous with fertilization. 2. The onset of pregnancy, marked by implantation of the blastocyst into the endometrium. 3. A basic understanding of a situation or a principle. From the Latin conceptio, conceptionis meaning conception, becoming pregnant; drawing up of legal formulae; and from the Latin conceptus meaning conceiving, pregnancy; collecting, or a collection.
Condition: The term "condition" has a number of biomedical meanings including the following: - An unhealthy state, such as in "this is a progressive condition."
- A state of fitness, such as "getting into condition."
- Something that is essential to the occurrence of something else; essentially a "precondition."
- As a verb: to cause a change in something so that a response that was previously associated with a certain stimulus becomes associated with another stimulus; to condition a person, as in behavioral conditioning.
CVS: 1. Chorionic villus sampling, a procedure for first-trimester prenatal diagnosis. 2. Cyclic vomiting syndrome, also known as abdominal migraine.
Decompress: 1. In general, to remove pressure physically or emotionally. 2. In surgery, to remove pressure on a structure such as the spinal cord. 3. To lessen atmospheric pressure on deep-sea divers returning to the surface, or on persons ascending to great heights.
Diagnosis: 1 The nature of a disease ; the identification of an illness. 2 A conclusion or decision reached by diagnosis. The diagnosis is rabies . 3 The identification of any problem. The diagnosis was a plugged IV. See the entire definition of Diagnosis
DNA: Deoxyribonucleic acid. One of two types of molecules that encode genetic information. (The other is RNA . In humans DNA is the genetic material; RNA is transcribed from it. In some other organisms, RNA is the genetic material and, in reverse fashion, the DNA is transcribed from it.) See the entire definition of DNA
Domain: In molecular biology, a discrete portion of a protein with its own function. The combination of domains in a single protein determines its overall function. (Not to be confused with an Internet domain.) See the entire definition of Domain
Dominant: A genetic trait is considered dominant if it is expressed in a person who has only one copy of that gene. (In genetic terms, a dominant trait is one that is phenotypically expressed in heterozygotes). See the entire definition of Dominant
Dwarfism: Abnormally short stature. Some forms are hereditary. The Little People of America (LPA) define dwarfism as an adult height of 148 cm (4 feet 10 inches) or less. Also known as nanism . Dwarfism is now more correctly called short stature. See the entire definition of Dwarfism
Ear: The hearing organ. There are three sections of the ear, according to the anatomy textbooks. They are the outer ear (the part we see along the sides of our head behind the temples), the middle ear, and the inner ear. But in terms of function, the ear has four parts: those three and the brain. Hearing thus involves all parts of the ear as well as the auditory cortex of the brain. The external ear helps concentrate the vibrations of air on the ear drum and make it vibrate. These vibrations are transmitted by a chain of little bones in the middle ear to the inner ear. There they stimulate the fibers of the auditory nerve to transmit impulses to the brain. See the entire definition of Ear
Ear tubes : Formally known as tympanostomy tubes, ear tubes are small plastic tubes inserted into the eardrum (the tympanum) to keep the middle ear aerated for a prolonged period of time. To put the tubes in place, a myringotomy (a surgically placed tiny incision in the eardrum) is done. Any fluid, usually thickened secretions, will be removed. The ear tubes usually remain in place for 6 months to several years. Water should not be allowed to enter the ear canal while the tubes are in place. Eventually, they will move out of the eardrum (extrude) and fall into the ear canal. The doctor may remove the tube during a routine future office visit or it may simply fall out of the ear without the child realizing it. See the entire definition of Ear tubes
Elbow: The juncture of the long bones in the middle portion of the arm. The bone of the upper arm (humerus) meets both the ulna (the inner bone of the forearm) and radius (the outer bone of the forearm) to form a hinge joint at the elbow. The radius and ulna also meet one another in the elbow to permit a small amount of rotation of the forearm. The elbow therefore functions to move the arm like a hinge (forward and backward) and in rotation (outward and inward). The biceps muscle is the major muscle that flexes the elbow hinge, and the triceps muscle is the major muscle that extends it. The primary stability of the elbow is provided by the ulnar collateral ligament, located on the medial (inner) side of the elbow. The outer bony prominence of the elbow is the lateral epicondyle, a part of the humerus bone. Tendons attached to this area can be injured, causing inflammation or tendonitis (lateral epicondylitis, or tennis elbow). The inner portion of the elbow is a bony prominence called the medial epicondyle of the humerus. Additional tendons from muscles attach here and can be injured, likewise causing inflammation or tendonitis (medial epicondylitis, or golfer's elbow). See also: Elbow bursitis ; Elbow pain ; Nursemaid's elbow. See the entire definition of Elbow
Essential: 1. Something that cannot be done without. 2. Required in the diet, because the body cannot make it. As in an essential amino acid or an essential fatty acid. 3. Idiopathic. As in essential hypertension. "Essential" is a hallowed term meaning "We don't know the cause."
Extension: The process of straitening or the state of being strait. Extension of the hip and knee joints is necessary to stand up from the sitting position. See the entire definition of Extension
Eye: The organ of sight. The eye has a number of components. These components include but are not limited to the cornea, iris, pupil, lens, retina, macula, optic nerve, choroid and vitreous. See the entire definition of Eye
Father: (1) The male parent. (2) One who originates. For example, "Wilhelm Roentgen is considered the father of radiology." (3) To produce offspring as a male. (4) To provide paternal protection and guidance to children.
FGFR3: Abbreviation for fibroblast growth factor receptor 3. Mutations in the FGFR3 gene are known to cause three different syndromes -- hypochondroplasia, achondroplasia, and thanatophoric dysplasia. These syndromes represent variations in severity. Hypochondroplasia is the mildest and thanatophoric dysplasia (also called thanatophoric dwarfism) is the most severe. In fact, thanatophoric dysplasia is a type of dwarfism in which death usually occurs in the first hours of life. FGF3 is an example of how different syndromes can result from mutations in a single gene.
Fibroblast: A cell ubiquitous in connective tissue that makes and secretes collagen.
Foot: The end of the leg on which a person normally stands and walks. The foot is an extremely complex anatomic structure made up of 26 bones and 33 joints that must work together with 19 muscles and 107 ligaments to execute highly precise movements. At the same time the foot must be strong to support more than 100,000 pounds of pressure for every mile walked. Even small changes in the foot can unexpectedly undermine its structural integrity and cause pain with every step. See the entire definition of Foot
Foramen: A natural opening. Although a foramen is usually through bone, it can be an opening through other types of tissue, as with the foramen ovale in the heart. The plural of foramen is foramina.
Foramen magnum: The large hole at the base of the skull which allows passage of the spinal cord. See the entire definition of Foramen magnum
Frontal: In anatomy, pertaining to the forehead. As, for example, the frontal bone, frontal sinus, and frontal nerve. From the Latin "frons" meaning the forehead or brow. See the entire definition of Frontal
Gene: The basic biological unit of heredity . A segment of deoxyribonucleic acid (DNA) needed to contribute to a function. See the entire definition of Gene
Genes: The basic biological units of heredity . Segments of deoxyribonucleic acid (DNA) needed to contribute to a function. See the entire definition of Genes
Genetic: Having to do with genes and genetic information.
Genu: The Latin word for the knee. When the knee is referred to in medicine, it is just called the knee. However, the word "genu" is also used in medicine as in: genu recurvatum (hyperextension of the knee), genu valgum (knock knee) and genu varum (bowleg). See the entire definition of Genu
Glycine: An amino acid, one of the 20 building blocks of protein. A nonessential amino acid, glycine is part of many proteins, participates in purine synthesis, and is a neurotransmitter. Symbol: Gly.
Growth hormone: A hormone made in the pituitary gland that stimulates the release of another hormone called somatomedin by the liver, thereby causing growth. Also known as somatotropin. Growth hormone is produced by the anterior pituitary gland, the front section of the gland, and is a polypeptide that consists of 191 amino acids . Growth hormone is given to children with pituitary dwarfism (short stature due to underfunction of the anterior pituitary) to help them grow. Excessive growth hormone production in children can lead to gigantism, and in adults it can lead to acromegaly. See the entire definition of Growth hormone
Heterozygous: Possessing two different forms of a particular gene , one inherited from each parent. A person who is heterozygous is called a heterozygote or a gene carrier. See the entire definition of Heterozygous
Homozygous: Possessing two identical forms of a particular gene, one inherited from each parent.
Hormone: A chemical substance produced in the body that controls and regulates the activity of certain cells or organs. See the entire definition of Hormone
Human growth: See: Normal growth.
Hydrocephalus : Hydrocephalus is an abnormal buildup of cerebrospinal fluid (CSF) in the ventricles of the brain. The fluid is often under increased pressure and can compress and damage the brain. See the entire definition of Hydrocephalus
Hypochondroplasia: Hypochondroplasia is a type of short-limb dwarfism with shortening especially of the ends of the limbs (termed rhizomelic dwarfism). The short stature and limb shortening can be mild. See the entire definition of Hypochondroplasia
Hypoplasia: Underdevelopment or incomplete development of a tissue or organ. For example, there can be hypoplasia (underdevelopment) of the enamel of the teeth. Hypoplasia is less drastic than aplasia where there is no development at all.
Hypotonia: Decreased tone of skeletal muscles. In a word, floppiness. Hypotonia is a common finding in cerebral palsy and other neuromuscular disorders. Untreated hypotonia can lead to hip dislocation and other problems. Treatment is via physical therapy. In some cases braces may be needed to permit a full range of movement despite hypotonia.
Intervention: The act of intervening, interfering or interceding with the intent of modifying the outcome. In medicine, an intervention is usually undertaken to help treat or cure a condition. For example, early intervention may help children with autism to speak. "Acupuncture as a therapeutic intervention is widely practiced in the United States," according to the National Institutes of Health. From the Latin intervenire, to come between.
Joint: A joint is the area where two bones are attached for the purpose of motion of body parts. A joint is usually formed of fibrous connective tissue and cartilage. An articulation or an arthrosis is the same as a joint. See the entire definition of Joint
Kyphosis: Outward curvature of the spine, causing a humped back. See the entire definition of Kyphosis
Laminectomy: A surgical procedure in which the posterior arch of a vertebra is removed. Laminectomy is done to relieve pressure on the spinal cord or on the nerve roots that emerge from the spinal canal. The procedure may be used to treat a slipped or herniated disk or to treat spinal stenosis.
Limb: The arm or leg.
Linkage: The tendency for genes and other genetic markers to be inherited together because of their location near one another on the same chromosome . See the entire definition of Linkage
Locus: The place, in Latin.. In genetics, a locus is the place a gene occupies on a chromosome. One locus, two loci.
Lordosis: Inward curvature of the spine. Normally, for example, the low back demonstrates lordosis. The spine is not supposed to be absolutely straight, so some degree of curvature is normal. When the curve exceeds the usual range, it may be due to musculoskeletal disease or simple poor posture. Treatment is usually by physical therapy, although in severe cases surgery, casting, and/or bracing may be required. Also known as swayback.
Lumbar: Referring to the 5 lumbar vertebrae which are situated below the thoracic vertebrae and above the sacral vertebrae in the spinal column. The 5 lumbar vertebrae are represented by the symbols L1 through L5. There are correspondingly 5 lumbar nerves.
Megalencephaly: Also called macrencephaly, a condition in which there is an abnormally large, heavy, and usually malfunctioning brain. By definition, the brain weight is greater than average for the age and gender of the child. Head enlargement may be evident at birth or the head may become abnormally large in the early years of life. See the entire definition of Megalencephaly
Middle ear: There are three sections of the ear. They are the external ear, the middle ear, and the inner ear. The middle ear consists of the ear drum (the tympanum or tympanic membrane) and, beyond it, a cavity. This cavity is connected via a canal (the Eustachian tube) to the pharynx (the nasopharynx). The Eustachian tube permits the gas pressure in the middle ear cavity to adjust to external air pressure (so, as you're descending in a plane, it's the Eustachian tube that opens when your ears "open"). The middle ear cavity also contains a chain of 3 little bones (ossicles) that connect the ear drum to the internal ear. The ossicles are named (not the Nina, the Pinta and the Santa Maria, but) the malleus, incus, and stapes. In terms of function, the middle ear communicates with the pharynx, equilibrates with external pressure and transmits the ear drum vibrations to the inner ear. See the entire definition of Middle ear
Motor: In medicine, having to do with the movement of a part of the body. Something that produces motion or refers to motion. For example, a motor neuron is a nerve cell that conveys an impulse to a muscle causing it to contract. The term "motor" today is also applied to a nerve that signals a gland to secrete. Motor is as opposed to sensory.
Muscle: Muscle is the tissue of the body which primarily functions as a source of power. There are three types of muscle in the body. Muscle which is responsible for moving extremities and external areas of the body is called "skeletal muscle." Heart muscle is called "cardiac muscle." Muscle that is in the walls of arteries and bowel is called "smooth muscle."
Mutant: An individual with a mutant (changed) gene.
Mutation: A permanent change, a structural alteration, in the DNA or RNA . In humans and many other organisms, mutations occur in DNA. However, in retroviruses like HIV , mutations occur in RNA which is the genetic material of retroviruses. See the entire definition of Mutation
Nasal: Having to do with the nose. Nasal drops are intended for the nose, not (for example) the eyes. The word "nasal" came from the Latin "nasus" meaning the nose or snout.
Nucleotide: A subunit of DNA or RNA. To form a DNA or RNA molecule, thousands of nucleotides are joined in a long chain. See the entire definition of Nucleotide
Obesity: The state of being well above one's normal weight. See the entire definition of Obesity
Overweight: The term "overweight" is used in two different ways. In one sense it is a way of saying imprecisely that someone is heavy. The other sense of "overweight" is more precise and designates a state between normal weight and obesity . See the entire definition of Overweight
Ovum: An egg in the ovary of the female. This egg is called the female "gamete" or sex cell. It combines with the male gamete, called a sperm, to form a zygote. This formation process is called "fertilization." (see sperm, zygote).
Paternal: 1. Pertaining to the father as, for example, a paternal age effect. 2. Related through the father as, for example, the paternal grandparents. 3. Inherited from the father as, for example, the paternal X chromosome.
Pediatric: Pertaining to children.
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. See the entire definition of Pregnancy
Pregnant: The state of carrying a developing fetus within the body. See the entire definition of Pregnant
Prenatal: Occurring or existing before birth. See the entire definition of Prenatal
Prenatal diagnosis: Diagnosis before birth. Methods for prenatal diagnosis include ultrasound of the uterus, placenta, and/or developing fetus; chorionic villus sampling (CVS) to obtain tissue for chromosome or biochemical analysis; and amniocentesis to obtain amniotic fluid for the analysis of chromosomes, enzymes, or DNA. A growing number of birth defects and diseases can be diagnosed prenatally, and in some cases treated before birth. Also known as antenatal diagnosis.
Protein: A large molecule 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. See the entire definition of Protein
Proximal: Toward the beginning, the nearer of two (or more) items. For example, the proximal end of the femur is part of the hip joint, and the shoulder is proximal to the elbow. The opposite of proximal is distal. See the entire definition of Proximal
Radiology: The branch of medicine that uses ionizing and nonionizing radiation for the diagnosis and treatment of disease. See the entire definition of Radiology
Range: In medicine and statistics, the difference between the lowest and highest numerical values. For example, if five premature infants are born weighing two, three, four, four, and five pounds respectively, the range of their birth weights is two to five pounds.
Receptor: 1. In cell biology, a structure on the surface of a cell (or inside a cell) that selectively receives and binds a specific substance. There are many receptors. There is a receptor for ( insulin ; there is a receptor for low-density lipoproteins ( LDL ); etc. To take an example, the receptor for substance P, a molecule that acts as a messenger for the sensation of pain , is a unique harbor on the cell surface where substance P docks. Without this receptor, substance P cannot dock and cannot deliver its message of pain. Variant forms of nuclear hormone receptors mediate processes such as cholesterol metabolism and fatty acid production. Some hormone receptors are implicated in diseases such as diabetes and certain types of cancer. A receptor called PXR appears to jump-start the body's response to unfamiliar chemicals and may be involved in drug-drug interactions. 2. In neurology, a terminal of a sensory nerve that receives and responds to stimuli. See the entire definition of Receptor
Respiration: 1. The act of inhaling and exhaling air in order to exchange oxygen for carbon dioxide. Synonymous with breathing and ventilation. 2. The cellular metabolic process by which oxygen is taken in, substances are oxidized, energy is released, and carbon dioxide and oxidized products are given off.
Rest: 1. Repose. Relaxation. 2. A fragment of embryonic tissue that has been retained after the period of embryonic development. Also called an embryonic rest.
Skeletal: Pertaining to the skeleton, the bones of the body which collectively provide the framework for the body.
Skull: The skull is a collection of bones which encase the brain and give form to the head and face. The bones of the skull include the following: the frontal, parietal, occipital, temporal, sphenoid, ethmoid, zygomatic, maxilla, nasal, vomer, palatine, inferior concha, and mandible. See the entire definition of Skull
Sperm: A sperm is the male "gamete" or sex cell. It combines with the female "gamete," called an ovum, to form a zygote. The formation process is called "fertilization." (see ovum, zygote).
Spinal cord: The major column of nerve tissue that is connected to the brain and lies within the vertebral canal and from which the spinal nerves emerge. Thirty-one pairs of spinal nerves originate in the spinal cord: 8 cervical , 12 thoracic , 5 lumbar, 5 sacral, and 1 coccygeal. The spinal cord and the brain constitute the central nervous system ( CNS ). The spinal cord consists of nerve fibers that transmit impulses to and from the brain. Like the brain, the spinal cord is covered by three connective-tissue envelopes called the meninges . The space between the outer and middle envelopes is filled with cerebrospinal fluid ( CSF ), a clear colorless fluid that cushions the spinal cord against jarring shock. Also known simply as the cord. See the entire definition of Spinal cord
Spinal cord compression: The act of exerting an abnormal amount of pressure on the spinal cord. Compression of the spinal cord may, for instance, be due to a fracture of the spine or a tumor pressing on the spinal cord.
Sporadic: Occurring upon occasion or in a scattered, isolated or seemingly random way. See the entire definition of Sporadic
Stenosis: A narrowing, as in: - aortic stenosis (narrowing of the aortic valve of the heart),
- pulmonary stenosis (narrowing of the pulmonary valve of the heart),
- pyloric stenosis (narrowing of the outlet of the stomach), and
- spinal stenosis (narrowing of the vertebral canal).
See the entire definition of Stenosis
Surgery: The word "surgery" has multiple meanings. It is the branch of medicine concerned with diseases and conditions which require or are amenable to operative procedures. Surgery is the work done by a surgeon. By analogy, the work of an editor wielding his pen as a scalpel is s form of surgery. A surgery in England (and some other countries) is a physician's or dentist's office. See the entire definition of Surgery
Trait: In genetics, a trait refers to any genetically determined characteristic. In technical terms, a genetic trait is amenable to segregation analysis rather than quantitative analysis. See the entire definition of Trait
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. See the entire definition of Tubes
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. See the entire definition of Ultrasound
Varum: See: Varus.
Villus: 1. A tiny finger-like or hair-like projection. 2. A small vascular protrusion. Villus is the Latin word for shaggy hair or fleece. The plural is villi. See the entire definition of Villus
X-ray: 1. High-energy radiation with waves shorter than those of visible light. X-rays possess the properties of penetrating most substances (to varying extents), of acting on a photographic film or plate (permitting radiography), and of causing a fluorescent screen to give off light (permitting fluoroscopy). In low doses X-rays are used for making images that help to diagnose disease, and in high doses to treat cancer . Formerly called a Roentgen ray. 2. An image obtained by means of X-rays. See the entire definition of X-ray
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From the Doctors at MedicineNet.com  |
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- Ear Tubes - Learn about ear tubes (myringotomy), a procedure that allows ventilation in the middle ear. Pre-surgery, during surgery, post surgery, and follow-up information is included. Source:MedicineNet
- Amniocentesis - Source:MedicineNet
- Obesity - Learn about obesity and being overweight including the health risks, causes, review of weight loss diet plans, surgical and non-surgical treatments, and medications to treat the disease. Source:MedicineNet
- Read 20 more Achondroplasia related articles ...
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