Amenorrhea Glossary of Terms

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Acromegaly: Condition due to the production of too much growth hormone by the pituitary gland after the end of adolescence.
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Amenorrhea: Absence or cessation of menstruation. Amenorrhea is conventionally divided into primary and secondary amenorrhea.
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Anatomy: The study of form. Gross anatomy involves structures that can be seen with the naked eye. It is as opposed to microscopic anatomy (or histology) which involves structures seen under the microscope. Traditionally, both gross and microscopic anatomy have been studied in the first year of medical school in the U.S. The most celebrated textbook of anatomy in the English-speaking world is Gray's Anatomy, still a useful reference book. The word "anatomy" comes from the Greek ana- meaning up or through + tome meaning a cutting. Anatomy was once a "cutting up" because the structure of the body was originally learned through dissecting it, cutting it up. The abbreviation for anatomy is anat.

Androgen: A male sex hormone that promotes the development and maintenance of the male sex characteristics. The major androgen is testosterone.

Anxiety: A feeling of apprehension and fear characterized by physical symptoms such as palpitations, sweating, and feelings of stress. Anxiety disorders are serious medical illnesses that affect approximately 19 million American adults. These disorders fill people's lives with overwhelming anxiety and fear. Unlike the relatively mild, brief anxiety caused by a stressful event such as a business presentation or a first date, anxiety disorders are chronic, relentless, and can grow progressively worse if not treated.
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Aplasia: Failure to develop. If something develops and then wastes away, that is atrophy.

Autoimmune: Pertaining to autoimmunity, a misdirected immune response that occurs when the immune system goes awry and attacks the body itself.
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Birth control: Birth control is the use of any practices, methods, or devices to prevent pregnancy from occurring in a sexually active woman. Also referred to as family planning, pregnancy prevention, fertility control, or contraception; birth control methods are designed either to prevent fertilization of an egg or implantation of a fertilized egg in the uterus.
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Bone density: Bone density is the amount of bone tissue in a certain volume of bone. It can be measured using a special x-ray called a quantitative computed tomogram.

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."

Brain tumor: A benign or malignant growth in the brain. Primary brain tumors arise in brain tissue. Secondary brain tumors are cancers that have spread to the brain tissue (metastasized) from elsewhere in the body. Brain tumors can and do occur at any age.

Breastfeeding: Feeding a child human breast milk. According to the American Academy of Pediatrics, human breast milk is preferred for all infants. This includes even premature and sick babies, with rare exceptions. It is the food least likely to cause allergic reactions; it is inexpensive; it is readily available at any hour of the day or night; babies accept the taste readily; and the antibodies in breast milk can help a baby resist infections.
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Cervix: The cervix is the lower, narrow part of the uterus (womb). The uterus, a hollow, pear-shaped organ, is located in a woman's lower abdomen, between the bladder and the rectum. The cervix forms a canal that opens into the vagina, which leads to the outside of the body.

Chemotherapy: 1. In the original sense, a chemical that binds to and specifically kills microbes or tumor cells. The term chemotherapy was coined in this regard by Paul Ehrlich (1854-1915).
2. In oncology, drug therapy for cancer. Also called "chemo" for short.
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Chronic: This important term in medicine comes from the Greek chronos, time and means lasting a long time.
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Chronic disease: A disease that persists for a long time. A chronic disease is one lasting 3 months or more, by the definition of the U.S. National Center for Health Statistics. Chronic diseases generally cannot be prevented by vaccines or cured by medication, nor do they just disappear. Eighty-eight percent of Americans over 65 years of age have at least one chronic health condition (as of 1998). Health damaging behaviors - particularly tobacco use, lack of physical activity, and poor eating habits - are major contributors to the leading chronic diseases.
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Craniopharyngioma: A type of benign brain tumor that emerges develops from embryonic tissue that forms part of the pituitary gland. Pressure on the pituitary by the tumor reduces the availability of the hormone vasopressin, raising the pressure within the cranium. A craniopharyngioma usually includes hard, calcified components within the tumor itself, and disrupts normal skull development in its vicinity. Treatment is usually via surgery.

CT scan: Computerized tomography scan. Pictures of structures within the body created by a computer that takes the data from multiple X-ray images and turns them into pictures on a screen. CT stands for computerized tomography.
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Cushing syndrome: The constellation of symptoms and signs caused by an excess of cortisol hormone.
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Depression: An illness that involves the body, mood, and thoughts, that affects the way a person eats and sleeps, the way one feels about oneself, and the way one thinks about things. A depressive disorder is not the same as a passing blue mood. It is not a sign of personal weakness or a condition that can be wished away. People with a depressive disease cannot merely "pull themselves together" and get better. Without treatment, symptoms can last for weeks, months, or years. Appropriate treatment, however, can help most people with depression.
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Dopamine: An important neurotransmitter (messenger) in the brain.
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Dysfunction: Difficult function or abnormal function.
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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.)
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Endocrinology: The study of hormones, their receptors, the intracellular signalling pathways they invoke, and the diseases and conditions associated with them.
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Endometrium: The uterine lining; the cells that line the uterus (the womb); the inner layer of the uterus. This tissue is shed monthly in response to the hormonal changes of the menstrual period. The endometrium then grows back and slowly gets thicker and thicker until the next period when it is once again sloughed off.

Estrogen: Estrogen is a female hormone produced by the ovaries. Estrogen deficiency can lead to osteoporosis.
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Fracture: A break in bone or cartilage. Although usually the result of trauma, a fracture can be caused by an acquired disease of bone such as osteoporosis or by abnormal formation of bone in a disease such as osteogenesis imperfecta ("brittle bone disease"). Fractures are classified according to their character and location as, for example, a greenstick fracture of the radius.
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Galactorrhea: The spontaneous flow of milk from the nipple at any time other than during nursing.
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Galactose: A sugar contained in milk. Galactose makes up half of the sugar called lactose that is found in milk. Lactose is called a disaccharide, the prefix "di" meaning 2, since lactose is made up of two sugars, galactose and glucose, bound together.
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Galactosemia: A genetic metabolic disease in which there is a defect in the body's ability to use the sugar galactose. In classic galactosemia, the basic defect is a deficiency of the enzyme known as GALT (galactose-1-phosphate uridyl transferase). This causes an accumulation of galactose 1-phosphate which damages the liver, eye, brain and kidney. Galactosemia is one of the diseases in many newborn screening panels. The disease can be fatal, if undetected. If detected, it can be treated by avoiding galactose in the diet.
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Genetic: Having to do with genes and genetic information.

Genetics: The scientific study of heredity. Genetics pertains to humans and all other organisms. So, for example, there is human genetics, mouse genetics, fruitfly genetics, etc.
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Genital: Pertaining to the external and internal organs of reproduction. (Not to be confused with genetic.)

Gland: 1. A group of cells that secrete a substance for use in the body. For example, the thyroid gland. 2. A group of cells that removes materials from the circulation. For example, a lymph gland.

Gynecology: The branch of medicine particularly concerned with the health of the female organs of reproduction and diseases thereof.
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Headache: A pain in the head with the pain being above the eyes or the ears, behind the head (occipital), or in the back of the upper neck. Headache, like chest pain or back ache, has many causes.
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Hirsutism: Having an overabundance of hair. A person with hirsutism is said to be hirsute (pronounced hir-suit).
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Hormone: A chemical substance produced in the body that controls and regulates the activity of certain cells or organs.
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Hot flashes: A sudden wave of mild or intense body heat caused by rushes of hormonal changes resulting from decreased levels of estrogen. Hot flashes can occur at any time and may last from a few seconds to a half-hour. They are due to blood vessel opening and constricting and a symptom of menopause.
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Hymen: A thin membrane which completely or partially occludes the vaginal opening. The hymen is a fold of mucous membrane usually present at birth at the orifice of the vagina. It is also called the vaginal membrane (or, sometimes, the virginal membrane).
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Hypothalamus: The area of the brain that controls body temperature, hunger, and thirst.

Hysteroscopy: A procedure to see inside the uterus (the womb) using a viewing tube that is inserted into the vagina up through the cervix into the uterus.

Intracranial: Within the cranium, the bony dome that houses and protects the brain.
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Intrauterine: In the uterus (the womb). As opposed to extrauterine: outside the uterus.
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Lactation: The process of milk production. Human milk is secreted by the mammary glands, which are located within the fatty tissue of the breast. The hormone oxytocin is produced in response to the birth of a new baby, and it both stimulates uterine contractions and begins the lactation process. For the first few hours of nursing, a special fluid called colostrum is delivered, which is especially high in nutrients, fats, and antibodies to protect the newborn from infection. Thereafter the amount of milk produced is controlled primarily by the hormone prolactin, which is produced in response to the length of time the infant nurses at the breast.
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Luteinizing hormone: A hormone released by the pituitary gland in response to luteinizing hormone- releasing hormone. Abbreviated LH, it controls the length and sequence of the female menstrual cycle, including ovulation, preparation the uterus for implantation of a fertilized egg, and ovarian production of both estrogen and progesterone. In males, it stimulates the testes to produce androgen. Also known as interstitial-cell-stimulating hormone (ICSH).

Malnutrition: A term used to refer to any condition in which the body does not receive enough nutrients for proper function. Malnutrition may range from mild to severe and life-threatening. It can be a result of starvation, in which a person has an inadequate intake of calories, or it may be related to a deficiency of one particular nutrient (for example, vitamin C deficiency). Malnutrition can also occur because a person can not properly digest or absorb nutrients from the food they consume, as may occur with certain medical conditions. Malnutrition remains a significant global problem, especially in developing countries.

Membrane: A very thin layer of tissue that covers a surface.

Menarche: The time in a girl's life that menstruation first begins. During the menarche period, menstruation may be irregular and unpredictable. Mood, weight, activity level, and growth rate may fluctuate with the hormone levels as well. Synonymous with female puberty.

Menopause: The time in a woman's life when menstrual periods permanently stop; it is also called the "change of life." Menopause is the opposite of the menarche.
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Menstrual: Pertaining to menstruation (the menses), as in last menstrual period, menstrual cramps, menstrual cycle, and premenstrual syndrome. From the Latin menstrualis, from mensis meaning month.

Menstrual cycle: The monthly cycle of changes in the ovaries and the lining of the uterus (endometrium), starting with the preparation of an egg for fertilization. When the follicle of the prepared egg in the ovary breaks, it is released for fertilization and ovulation occurs. Unless pregnancy occurs, the cycle ends with the shedding of part of the endometrium, which is menstruation. Although it is actually the end of the physical cycle, the first day of menstrual bleeding is designated as "day 1" of the menstrual cycle in medical parlance.

Menstruation: The periodic blood that flows as a discharge from the uterus. Also called menorrhea, the time during which menstruation occurs is referred to as menses. The menses occurs at approximately 4 week intervals to compose the menstrual cycle.

MRI: Abbreviation and nickname for magnetic resonance imaging. For more information, see: Magnetic Resonance Imaging; Paul C. Lauterbur; Peter Mansfield.

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).

Night sweats: Severe hot flashes which occur at night and result in a drenching sweat. Night sweats can have many different causes including medications, infections, and cancers.

Obstetrics: The art and science of managing pregnancy, labor and the puerperium (the time after delivery).

Onset: In medicine, the first appearance of the signs or symptoms of an illness as, for example, the onset of rheumatoid arthritis. There is always an onset to a disease but never to the return to good health. The default setting is good health.
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Oophoritis: Inflammation of the ovary or egg sac.

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.

Ovarian: Of or pertaining to the ovary.

Ovary: The female gonad, the ovary is one of a pair of reproductive glands in women. They are located in the pelvis, one on each side of the uterus. Each ovary is about the size and shape of an almond. The ovaries produce eggs (ova) and female hormones. During each monthly menstrual cycle, an egg is released from one ovary. The egg travels from the ovary through a fallopian tube to the uterus. The ovaries are the main source of female hormones, which control the development of female body characteristics, such as the breasts, body shape, and body hair. They also regulate the menstrual cycle and pregnancy.

Ovulation: The release of the ripe egg from the ovary. The egg is released when the cavity surrounding it (the follicle) breaks open in response to a hormonal signal. Ovulation occurs around fourteen or fifteen days from the first day of the woman's last menstrual cycle. When ovulation occurs, the ovum moves into the fallopian tube and becomes available for fertilization.

Peripheral: Situated away from the center, as opposed to centrally located.
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Peripheral vision: Side vision. The ability to see objects and movement outside of the direct line of vision. Peripheral vision is the work of the rods, nerve cells located largely outside the macula (the center) of the retina. The rods are also responsible for night vision and low-light vision but are insensitive to color. As opposed to central vision.

Pharmacy: A location where prescription drugs are sold. A pharmacy is, by law, constantly supervised by a licensed pharmacist.

Pituitary: 1. As an adjective, pertaining to the pituitary gland or its hormonal secretions. 2. As a noun, the pituitary gland itself.
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Pituitary gland: The main endocrine gland. It is a small structure in the head. It is called the master gland because it produces hormones that control other glands and many body functions including growth. The pituitary consists of the anterior and posterior pituitary.
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Polycystic ovary syndrome: Abbreviated PCOS. Polcystic ovary syndrome is a condition in women characterized by irregular or no menstrual periods, acne, obesity, and excess hair growth. PCOS is a disorder of chronically abnormal ovarian function and hyperandrogenism (abnormally elevated androgen levels). It affects 5-10% of women of reproductive age. PCOS is also called the Stein-Leventhal syndrome.
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Postpartum: In the period just after delivery, as with postpartum depression. Postpartum refers to the mother and postnatal to the baby. From the Latin post, after + partum, birth.

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.
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Pregnant: The state of carrying a developing fetus within the body.
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Primary amenorrhea: Absence of menstruation. Amenorrhea is conventionally divided into primary and secondary amenorrhea. With primary amenorrhea, menstruation never takes place. It fails to occur at puberty. With secondary amenorrhea, menstruation starts but then stops. The absence of menstruation during pregnancy is a form of physiologic amenorrhea, physiologic in the sense that it is completely normal and is not caused by anything pathologic. Amenorrhea during lactation is another type of physiologic amenorrhea. The word "amenorrhea" is compounded from three Greek roots "a-", no + "men", month + "rhoia", flow = no monthly flow. Amenorrhea is less commonly called amenia.

Progesterone: A female hormone and the principal progestational hormone that is made mainly by the corpus luteum in the ovary and by the placenta. Progesterone prepares the lining (endometrium) of the uterus (the womb) to receive and sustain the fertilized egg and so permits pregnancy. Similarly refers to synthetic versions of the hormone. Also known as progestational hormone.

Progestin: Any one of a group of steroid hormones that have the effect of progesterone.

Prolactin: A hormone secreted by the pituitary gland. Prolactin stimulates lactation (milk production). It also has many other functions, including essential roles in the maintenance of the immune system.
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Psychiatric: Pertaining to or within the purview of psychiatry, the medical specialty concerned with the prevention, diagnosis, and treatment of mental illness.
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Psychotropic drug: Any drug capable of affecting the mind, emotions, and behavior. Some legal drugs such as lithium for depression are psychotropic. Many illicit drugs such as cocaine are also psychotropic. Also called a psychodynamic drug.
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Puberty: A complex biologic and psychologic process involving sexual development, accelerated growth, and adrenal maturation heralded by the secretion of gonadotropin releasing hormone (GnRH) from a part of the brain called the hypothalamus. This event is the first known step in the reproductive cascade. It initiates the pulsatile release of gonadotropins, gonadal secretion of sex steroids, pubertal development, and gametogenesis (the production of sperm and ova).
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Radiation: 1. Rays of energy. Gamma rays and X-rays are two of the types of energy waves often used in medicine. 2. The use of energy waves to diagnose or treat disease. See also: Irradiation.

Radiation therapy: The use of high-energy rays to damage cancer cells, stopping them from growing and dividing. Like surgery, radiation therapy is a local treatment that affects cancer cells only in the treated area.
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Saline: Relating to salt. As an adjective, "saline" means "salty, containing salt." As a noun "saline" is a salt solution, often adjusted to the normal salinity of the human body.
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Sarcoidosis: A disease of unknown origin that causes small lumps (granulomas) due to chronic inflammation to develop in a great range of body tissues. Sarcoidosis can appear in almost any body organ, but most often starts in the lungs or lymph nodes. It also affects the eyes, liver and skin; and less often the spleen, bones, joints, skeletal muscles, heart and central nervous system (brain and spinal cord).
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Scan: As a noun, the data or image obtained from the examination of organs or regions of the body by gathering information with a sensing device.
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Secondary amenorrhea: The abnormal cessation of menstruation. Amenorrhea is conventionally divided into primary and secondary . With primary amenorrhea, menstruation never takes place. It fails to occur at puberty. With secondary amenorrhea, menstruation starts but then stops. The absence of menstruation during pregnancy is a form of physiologic amenorrhea, physiologic in the sense that it is completely normal and is not caused by anything pathologic. Amenorrhea during lactation is another type of physiologic amenorrhea. The word "amenorrhea" is compounded from three Greek roots "a-", no + "men", month + "rhoia", flow = no monthly flow. Amenorrhea is less commonly called amenia.

Septum: A word borrowed from the Latin "saeptum" meaning a "dividing wall or enclosure."

Sleep: The body's rest cycle.
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Stress: Forces from the outside world impinging on the individual. Stress is a normal part of life that can help us learn and grow. Conversely, stress can cause us significant problems.
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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.
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Symptom: Any subjective evidence of disease. Anxiety, lower back pain, and fatigue are all symptoms. They are sensations only the patient can perceive. In contrast, a sign is objective evidence of disease. A bloody nose is a sign. It is evident to the patient, doctor, nurse and other observers.

Syndrome: A set of signs and symptoms that tend to occur together and which reflect the presence of a particular disease or an increased chance of developing a particular disease.
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Systemic: Affecting the entire body. A systemic disease such as diabetes can affect the whole body. Systemic chemotherapy employs drugs that travel through the bloodstream and reach and affect cells all over the body.

Teratoma: A type of germ cell tumor that may contain several different types of tissue and sometimes mature elements such as hair, muscle, and bone. Teratomas occur most often in the ovary, testis, and in the sacrococcygeal region (near the tailbone) in children. A teratoma may be benign or malignant.

Therapy: The treatment of disease.
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Thyroid: 1. The thyroid gland. Also, pertaining to the thyroid gland. 2. A preparation of the thyroid gland used to treat hypothyroidism. 3. Shaped like a shield. (The thyroid gland was so-named by Thomas Wharton in 1656 because it was shaped like an ancient Greek shield.)
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Transverse: In anatomy, a horizontal plane passing through the standing body so that the transverse plane is parallel to the floor.
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TSH: Stands for thyroid stimulating hormone, a hormone produced by the pituitary gland at the base of the brain in response to signals from the hypothalamus gland in the brain. TSH promotes the growth of the thyroid gland in the neck and stimulates it to produce more thyroid hormones. When there is an excessive amount of thyroid hormones, the pituitary gland stops producing TSH, reducing thyroid hormone production. This mechanism maintains a relatively constant level of thyroid hormones circulating in the blood.
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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.
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Tumor: An abnormal mass of tissue. Tumors are a classic sign of inflammation, and can be benign or malignant (cancerous). There are dozens of different types of tumors. Their names usually reflect the kind of tissue they arise in, and may also tell you something about their shape or how they grow. For example, a medulloblastoma is a tumor that arises from embryonic cells (a blastoma) in the inner part of the brain (the medulla). Diagnosis depends on the type and location of the tumor. Tumor marker tests and imaging may be used; some tumors can be seen (for example, tumors on the exterior of the skin) or felt (palpated with the hands).
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Turner syndrome: A chromosome disorder in females that is characterized by the absence of all or part of a second sex chromosome in some or all cells. The condition occurs in 1 in 2,500 to 3,000 girls born.
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Uterine lining: The inner layer of the uterus (womb); the cells that line the womb; anatomically termed the endometrium.
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Uterus: The uterus (womb) is a hollow, pear-shaped organ located in a woman's lower abdomen between the bladder and the rectum. The narrow, lower portion of the uterus is the cervix; the broader, upper part is the corpus. The corpus is made up of two layers of tissue.

Vagina: The muscular canal extending from the cervix to the outside of the body. It is usually six to seven inches in length, and its walls are lined with mucus membrane. It includes two vaultlike structures, the anterior (front) vaginal fornix and the posterior (rear) vaginal fornix. The cervix protrudes slightly into the vagina, and it is through a tiny hole in the cervix (the os) that sperm make their way toward the internal reproductive organs. The vagina also includes numerous tiny glands that make vaginal secretions.
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Weight loss: Weight loss is a decrease in body weight resulting from either voluntary (diet, exercise) or involuntary (illness) circumstances. Most instances of weight loss arise due to the loss of body fat, but in cases of extreme or severe weight loss, protein and other substances in the body can also be depleted. Examples of involuntary weight loss include the weight loss associated with cancer, malabsorption (such as from chronic diarrheal illnesses ), and chronic inflammation (such as with rheumatoid arthritis).

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.