Alopecia:Baldness. There are many types of alopecia, each with a different cause. Alopecia may be localized to the front and top of the head as in common male pattern baldness. It may be patchy as in a condition called alopecia areata. Or it can involve the entire head as in alopecia capitis totalis. The word "alopecia" comes from the Greek "alopex" for "fox." Foxes are less furry when afflicted with a skin disease (the "mange") which causes them to lose their hair. When a fancier word for "baldness" was sought, the mangy fox supplied it -- "alopecia" or, if you wish, "fox-mange" -- not a very positive image to associate with baldness!
Analysis: A psychology term for processes used to gain understanding of complex emotional or behavioral issues.
Anesthesia: Loss of feeling or awareness. A general anesthetic puts the person to sleep. A local anesthetic causes loss of feeling in a part of the body such as a tooth or an area of skin without affecting consciousness. Regional anesthesia numbs a larger part of the body such as a leg or arm, also without affecting consciousness. The term "conduction anesthesia" encompasses both local and regional anesthetic techniques. Many surgical procedures can be done with conduction anesthesia without significant pain. In many situations, such as a C-section, conduction anesthesia is safer and therefore preferable to general anesthesia. However, there are also many types of surgery in which general anesthesia is clearly appropriate.
Anesthetic: A substance that causes lack of feeling or awareness. A local anesthetic causes loss of feeling in a part of the body. A general anesthetic puts the person to sleep.
Antibiotic: A drug used to treat infections caused by bacteria and other microorganisms. Originally, an antibiotic was a substance produced by one microorganism that selectively inhibits the growth of another. Synthetic antibiotics, usually chemically related to natural antibiotics, have since been produced that accomplish comparable tasks. See the entire definition of Antibiotic
Aseptic: The absence of microorganisms. By contrast, something that just discourages the growth of microorganisms is antiseptic.
Aseptic necrosis: Condition in which poor blood supply to an area of bone leads to bone death. Also called avascular necrosis and osteonecrosis.
Bacillus: A large family of bacteria that have a rod-like shape. They include the bacteria that cause food to spoil, and also those responsible for some types of diseases. Helpful members of the bacillus family are used to make antibiotics, or colonize the human intestinal tract and aid with digestion.
Bacteria: Single-celled microorganisms which can exist either as independent (free-living) organisms or as parasites (dependent upon another organism for life). See the entire definition of Bacteria
BCG: An effective immunization against tuberculosis. BCG stands for Bacille Calmette Guerin. BCG is a weakened (attenuated) version of a bacteria called Mycobacterium bovis which is closely related to Mycobacterium tuberculosis, the agent responsible for tuberculosis. See the entire definition of BCG
Biopsy: The removal of a sample of tissue for purposes of diagnosis. (Many definitions of "biopsy" stipulate that the sample of tissue is removed for examination under a microscope. This may or may not be the case. The diagnosis may be achieved by other means such as by analysis of chromosomes or genes.) See the entire definition of Biopsy
Bumps: The raised area of a bump or bruise results from blood leaking from these injured blood vessels into the tissues as well as from the body's response to the injury. A purplish, flat bruise that occurs when blood leaks out into the top layers of skin is referred to as an ecchymosis.
CBC: A commonly used abbreviation in medicine that stands for 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. See the entire definition of CBC
CDC: The Centers for Disease Control and Prevention, the US agency charged with tracking and investigating public health trends. The stated mission of the CDC is "To promote health and quality of life by preventing and controlling disease, injury, and disability." The CDC is a part of the U.S. Public Health Services (PHS) under the Department of Health and Human Services (HHS). See the entire definition of CDC
Cell: The basic structural and functional unit in people and all living things. Each cell is a small container of chemicals and water wrapped in a membrane. See the entire definition of Cell
Centers for Disease Control and Prevention: The US agency charged with tracking and investigating public health trends. The stated mission of the Centers for Disease Control and Prevention, commonly called the CDC, is "To promote health and quality of life by preventing and controlling disease, injury, and disability." See the entire definition of Centers for Disease Control and Prevention
Chronic: This important term in medicine comes from the Greek chronos, time and means lasting a long time. See the entire definition of Chronic
Collagen: Collagen is the principal protein of the skin, tendons, cartilage, bone and connective tissue.
Creatinine: A chemical waste molecule that is generated from muscle metabolism. Creatinine is produced from creatine, a molecule of major importance for energy production in muscles. Approximately 2% of the body's creatine is converted to creatinine every day. Creatinine is transported through the bloodstream to the kidneys. The kidneys filter out most of the creatinine and dispose of it in the urine. See the entire definition of Creatinine
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
Endemic: Present in a community at all times but in relatively low frequency. Something that is endemic is typically restricted or peculiar to a locality or region. See the entire definition of Endemic
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.
Hair loss: Hair loss is the thinning of hair on the scalp. The medical term for hair loss is alopecia. Alopecia can be temporary or permanent. The most common form of hair loss occurs gradually and is referred to as "androgenetic alopecia," meaning that a combination of hormones (androgens are male hormones) and heredity (genetics) is needed to develop the condition. Other types of hair loss include alopecia areata (patches of baldness that usually grow back), telogen effluvium (rapid shedding after childbirth, fever, or sudden weight loss); and traction alopecia (thinning from tight braids or ponytails). See the entire definition of Hair loss
Immune: Protected against infection. The Latin immunis means free, exempt.
Immune response: Any reaction by the immune system.
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. See the entire definition of Infection
Inflammatory response: A fundamental type of response by the body to disease and injury, a response characterized by the classical signs of "dolor, calor, rubor, and tumor" -- pain, heat (localized warmth), redness, and swelling. See the entire definition of Inflammatory response
Intracellular: Within a cell. In contrast to extracellular, meaning outside a cell.
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."
Leper:1. Someone with leprosy (Hansen disease). The term leper is now in disfavor. 2. By extension, a pariah. A person who is avoided or shunned by society. From the French lepre, from the Greek lepros meaning scaly, referring to the scales that form on the skin in some cases of leprosy.
Leptospirosis: An infectious disease caused by a particular type of bacteria called a spirochete transmitted by rats as well as by skunks, opossums, raccoons, foxes, and other vermin. Leptospirosis occurs worldwide but is most commonly acquired in the tropics. About 100 cases of leptospirosis are reported each year in the US. The disease is becoming a greater risk as more people travel to undeveloped areas of the world. (Athletes who participated in the Eco-Challenge-Sabah 2000 multisport expedition in Borneo, Malaysia, in August 2000 contracted leptospirosis after coming in contact with the Segama River.). Symptoms begin from 2 to 25 days after, initial direct exposure to the urine or tissue of an infected animal. This can even occur via contaminated soil or water. Veterinarians and farm workers are at particularly high risk. See the entire definition of Leptospirosis
Lesion: Pronounced "lee-sion" with the emphasis on the "lee," a lesion can be almost any abnormality involving any tissue or organ due to any disease or any injury. See the entire definition of Lesion
Limb: The arm or leg.
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.
Lymph: An almost colorless fluid that travels through vessels called lymphatics in the lymphatic system and carries cells that help fight infection and disease.
Lymphocytes: A small white blood cell (leukocyte) that plays a large role in defending the body against disease. See the entire definition of Lymphocyte
Macules: Small circumscribed changes in the color of skin that are neither raised (elevated) nor depressed. Macules are never large. They are basically little spots or blemishes in the skin. They are entirely flat and can only be appreciated by visual inspection; they cannot be seen from the side. See the entire definition of Macules
Malaria: An infectious disease caused by protozoan parasites from the Plasmodium family that can be transmitted by the sting of the Anopheles mosquito or by a contaminated needle or transfusion. Falciparum malaria is the most deadly type. See the entire definition of Malaria
Microscope: An optical instrument that augments the power of the eye to see small objects. The name microscope was coined by Johannes Faber (1574-1629) who in 1628 borrowed from the Greek to combined micro-, small with skopein, to view. Although the first microscopes were simple microscopes, most (if not all) optical microscopes today are compound microscopes.
Microscopic: So small it cannot be seen without the aid of microscope. As opposed to macroscopic (large enough to be seen with naked eye). A tiny tumor is microscopic while a big tumor is macroscopic.
Minocycline: A tetracycline antibiotic used to treat many different bacteria in urinary tract infections, acne, gonorrhea, and chlamydia, and other injections. The brand names for minocycline include Dynacin, Minocin, and Vectrin. See the entire definition of Minocycline
Mycobacterium: A large family of bacteria that have unusually waxy cell walls that are resistant to digestion. See the entire definition of Mycobacterium
Mycobacterium leprae: The bacillus responsible for leprosy (Hansen disease). Mycobacterium leprae is an obligate parasite that has to live within cells. There it is able to withstand the onslaught of enzymes and other forces by virtue of possessing a peculiarly resistant waxy coat and thanks also to its association with lowered cellular immunity. See also: Hansen disease.
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.
Necrosis: The death of living cells or tissues. Necrosis can be due, for example, to ischemia (lack of blood flow). From the Greek "nekros" (dead body).
Nerve: A bundle of fibers that uses chemical and electrical signals to transmit sensory and motor information from one body part to another. See: Nervous system.
Neural: Having to do with nerve cells.
Nose: The external midline projection from the face. See the entire definition of Nose
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. See the entire definition of Pain
Papules: Small solid rounded bumps rising from the skin that are each usually less than 1 centimeter in diameter (less than 3/8 inch across). See the entire definition of Papules
Peripheral: Situated away from the center, as opposed to centrally located. See the entire definition of Peripheral
Peripheral nervous system (PNS): That portion of the nervous system that is outside the brain and spinal cord. See the entire definition of Peripheral nervous system
Progressive: Increasing in scope or severity. Advancing. Going forward. In medicine, a disease that is progressive is going from bad to worse.
Rabies: A potentially fatal viral infection that attacks the central nervous system. See the entire definition of Rabies
Regress: To return or go back, particularly to return to a pattern of behavior or level of skill characteristic of a younger age. For example, if a three-year-old child begins to regress by losing the ability to control his bowels or speak, that is a cause for medical concern. In reference to a disease, to "regress," means tending to worsen.
Residual: Something left behind. With residual disease, the disease has not been eradicated.
Resistance: Opposition to something, or the ability to withstand it. For example, some forms of staphylococcus are resistant to treatment with antibiotics.
Resolution: In genetics, resolution refers to the degree of molecular detail on a physical map of DNA, ranging from low to high.
Schistosomiasis: Diseases of liver, gastrointestinal tract and bladder caused by schistosomes, trematode worms that parasitize people. Infection is from infested water. See the entire definition of Schistosomiasis
Sensation: In medicine and physiology, sensation refers to the registration of an incoming (afferent) nerve impulse in that part of the brain called the sensorium, which is capable of such perception. Therefore, the awareness of a stimulus as a result of its perception by sensory receptors. (Sensory is here synonymous with sensation.) See the entire definition of Sensation
Smallpox: Also known as variola, a highly contagious and frequently fatal viral disease characterized by a biphasic fever and a distinctive skin rash that left pock marks in its wake. Because of its high case-fatality rates and transmissibility, smallpox now represents a serious bioterrorist threat. The disease is caused by the variola virus. The incubation period is about 12 days (range: 7 to 17 days) following exposure. Initial symptoms include high fever, fatigue, and head and back aches. A characteristic rash, most prominent on the face, arms, and legs, follows in 2-3 days. The rash starts with flat red lesions that evolve at the same rate. Lesions become pus-filled and begin to crust early in the second week. Scabs develop and then separate and fall off after about 3-4 weeks. See the entire definition of Smallpox
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
Syphilis: A sexually transmitted disease caused by Treponema pallidum, a microscopic organism called a spirochete. This worm-like, spiral-shaped organism infects people by burrowing into the moist mucous membranes of the mouth or genitals. From there, the spirochete produces a non-painful ulcer known as a chancre. There are three stages of syphilis: See the entire definition of Syphilis
Testicles: The testicles (also called testes or gonads) are the male sex glands. They are located behind the penis in a pouch of skin called the scrotum. The testicles produce and store sperm, and they are also the body's main source of male hormones (testosterone). These hormones control the development of the reproductive organs and other male characteristics, such as body and facial hair, low voice, and wide shoulders.
Tetanus: An often fatal infectious disease caused by the bacteria Clostridium tetani (C. tetani) which usually enters the body through a puncture, cut, or open wound. Tetanus is characterized by profoundly painful spasms of muscles, including "locking" of the jaw so that the mouth cannot open (lockjaw). C. tetani releases a toxin that affects the motor nerves, (the nerves which stimulate the muscles). See the entire definition of Tetanus
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. See the entire definition of Tuberculosis
World Health Organization: An agency of the United Nations established in 1948 to further international cooperation in improving health conditions. Although the World Health Organization inherited specific tasks relating to epidemic control, quarantine measures, and drug standardization from the Health Organization of the League of Nations (that was set up in 1923) and from the International Office of Public Health at Paris (established in 1909), the World Health Organization was given a broad mandate under its constitution to promote the attainment of "the highest possible level of health" by all people. WHO defines health positively as "a state of complete physical, mental, and social well-being and not merely the absence of disease or infirmity." See the entire definition of World Health Organization
Foot pain may be caused by injuries (sprains, strains, bruises, and fractures), diseases (diabetes, Hansen disease, and gout), viruses, fungi, and bacteria (plantar warts and athlete's foot), or even ingrown toenails. Pain and tenderness may be accompanied by joint looseness, swelling, weakness, discoloration, and loss of function. Minor foot pain can usually be treated with rest, ice, compression, and elevation and OTC medications such as acetaminophen and ibuprofen. Severe pain should be treated by a medical professional.
There are many causes of scalp hair loss. This featured article covers the common ones such as patchy hair loss (alopecia areata, trichotillomania, and tinea capitis), telogen effluvium, and androgenetic alopecia (male-pattern baldness, female-pattern baldness).
Alopecia areata is a condition that causes hair loss on the scalp and sometimes other parts of the body. It is believed to be caused by an abnormality of the immune system that causes the body's immune system to attack the hair follicles. Typically, hair regrows within a year without treatment. Steroid injections, creams, and shampoos may be used during treatment.
Travelers should prepare for their trip by visiting their physician to get the proper vaccinations and obtain the necessary medication if they have a medical condition or chronic disease. Diseases that travelers may pick up from contaminated water or food, insect or animal bites, or from other people include malaria, meningococcal meningitis, yellow fever, hepatitis A, typhoid fever, polio, and cholera.
Aseptic necrosis (avascular necrosis or osteonecrosis) is a condition that develops when blood supply diminishes to an area of bone and causes bone death. Though aseptic necrosis may be painless, pain is often associated when the degenerating bone is used. If caught early, aseptic necrosis may be treated by grafting new bone into the degenerating area. In later stages, joint replacement surgery may be required.
Blindness is the state of being sightless. Causes of blindness include macular degeneration, stroke, cataract, glaucoma, infection and trauma. Symptoms and signs may include eye pain, eye discharge, or the cornea or pupil turning white. Treatment of blindness depends upon the cause of the blindness.
There are many causes of scalp hair loss, and they do differ in men and women. This article will cover the common ones. Studies show that losing up to 100-150 hairs per day is normal. Human hair naturally grows in three phases: anagen, catagen, and telogen. Anagen is the active or growing phase.
Catagen is a fairly short phase of the natural hair cycle during which hairs begin to break down. Telogen is the resting phase. The hairs that are shed daily are often in the resting or late phase in the hair cycle. Normally, about 10% of the scalp hairs are in the resting or telogen phase at any time. These hairs are not growing and are getting prepared for cyclic shedding.
In general, most hair loss is not associated with systemic or internal disease, nor is poor diet a frequent factor. Frequently, hair may simply thin as a result of predetermined genetic factors, family history, and the overall aging process. Many men and women may n...