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Adenine (A)
Adenine (A)"One member of the A-T (adenine-thymine) base pair in DNA. The other base pair in DNA is G-C (guanine-cytosine). Each base pair forms a ""rung of the DNA ladder."" A DNA nucleotide is made of a molecule of sugar, a molecule of phosphoric acid, and a molecule called a base. The bases are the ""letters"" that spell out the genetic code. In DNA, the code letters are A, T, G, and C, which stand for the chemicals adenine, thymine, guanine, and cytosine, respectively. In DNA base pairing, adenine always pairs with thymine, and guanine always pairs with cytosine. Adenine is also one of the bases in RNA. There it always pairs with uracil (U). The base pairs in RNA are therefore A-U and G-C." RELATED TERMS-------------------------------------- Base A chemical compound that either donates hydroxide ions or absorbs hydrogen ions when dissolved in water. Bases and acids are referred to as opposites because the effect of an acid is to increase the hydronium ion concentration in water, whereas bases reduce this concentration. Arrhenius bases are water-soluble and always have a pH greater than 7 in solution. DNA Deoxyribo-Nucleic acid. DNA molecules carry the genetic information necessary for the organization and functioning of most living cells and control the inheritance of characteristics. Sugar A class of carbohydrates that taste sweet. Sugar is a quick and easy fuel for the body to use. Types of sugar are lactose, glucose, fructose, and sucrose. Genetic Hereditary. Having to do with the genes. Code The genetic code is the correspondence between the triplet of bases in DNA with the amino acids. Adenine A purine base found in RNA and DNA; in double-stranded DNA adenine pairs with the pyrimidine thymine. Thymine A nitrogenous base, one member of the base pair AT (adenine-thymine). Guanine (guanine triphosphate) One of the 4 types of nucleotides that make up DNA. Base pairs with cytosine by 3 hydrogen bonds. Cytosine One of the pyrimidine nitrogenous bases occurring in both DNA and RNA. Pairing A method by which subjects are selected so that two subjects with similar characteristics (for example, weight, smoking habits) are assigned to a set, but one receives Treatment A and the other receives Treatment B. RNA Ribonucleic acid. A long-chain, usually single-stranded. The primary function of RNA is protein synthesis within a cell. However, RNA is involved in various ways in the processes of expression and repression of hereditary information. The three main functionally distinct varieties of RNA molecules are: (1) messenger RNA (mRNA) which is involved in the transmission of DNA information, (2) ribosomal RNa (rRNA) which makes up the physical machinery of the synthetic process, and (3) transfer RNA (tRNA) which also constitutes another functional part of the machinery of protein synthesis. Uracil A nitrogenous base normally found in RNA but not DNA; uracil is capable of forming a base pair with adenine. SIMILAR TERMS-------------------------------------- Aden- See: Adeno-. Adena Regional Medical Center The Adena Regional Medical Center is a hospital in Chillicothe, Ohio, United States. Adenine A purine base found in RNA and DNA; in double-stranded DNA adenine pairs with the pyrimidine thymine. Adenitis Inflammation of a gland. Adeno- "Prefix referring to a gland, as in adenoma and adenopathy. From the Greek aden meaning originally ""an acorn"" and later ""a gland"" in the form of an acorn. Before a vowel, adeno- becomes aden-, as in adenitis (inflammation of a gland)." Adenocarcinoma A cancer that develops in the lining or inner surface of an organ. Adenocard Adenocard is a prescription or over-the-counter drug which is (or once was) legal in the United States and possibly in other countries. Active ingredient(s): adenosine . Adenoid cystic carcinoma "A type of cancer that most often develops in the salivary glands of the head and neck. It may arise in other sites such as the skin, lacrimal gland, trachea, breast, cervix and prostate. Adenoid cystic carcinoma (ACC) has a characteristic appearance under the microscope. Abnormal ""nests"" or cords of certain cells (epithelial cells) can be seen to surround or infiltrate ducts and glandular structures. These structures are typically filled with a mucous-like material or contain abnormal fibrous membranes (hyaline membranes). ACC is an unusual tumor. It is slow-growing but relentless. It tends to be locally invasive and infiltrate the ""sheaths"" or coatings surrounding nerve fibers (perineural spaces). ACC often recurs years later at the site where the tumor first arose or it may metastasize. Unlike most carcinomas, it seldom metastasizes to nearby lymph nodes but rather to distant sites. The lung is the most common site of metastasis, with the liver second. Bone metastases indicate a poor prognosis . Treatment usually involves surgery to resect (remove) the tumor. Postoperative radiotherapy may help prevent local recurrence. Chemotherapy may slow the tumor but no chemotherapy has yet been found that is effective in destroying it." Adenoidectomy The surgical removal of the adenoids. Adenoiditis Infection of the adenoids. Adenoids Glandular tissue in the back of the throat that may swell, especially during childhood, obstruct breathing and speaking, and lead to ear infections. Adenoids and Tonsils "These celebrated structures in the back of the throat are composed of tissue similar to the lymph nodes or ""glands."" " Adenoma A benign epithelial tumor in which the cells form glandular structures or are derived from glandular epithelium. Adenoma colon family history See: Colon cancer family history. Adenomatous polyposis coli See: APC (meaning 3). Adenomatous polyposis coli, autosomal recessive See: MYH. Adenomyoma A nodule that forms around tissue of the inner uterus (endometrial tissue) as a result of adenomyosis. See adenomyosis. Adenomyomata Plural form of adenomyoma. Adenomyosis Pronounced a-den-o- mi-o-sis, 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 are adjacent to one another, discrete neighbors. In adenomyosis, the endometrium boorishly implants itself in the myometrium. The myometrium may respond to this intrusion with muscular overgrowth. If an island of endometrial tissue is contained and circumscribed within the myometrium, it forms a nodule called an adenomyoma (plural: adenomyomata). Adenomyosis is made up of adeno (gland) + myo (muscle) + osis (a condition of) = a condition of glandular tissue (referring to the endometrium) in the muscle (the myometrium). Adenomyosis goes by several other names including endometriosis interna, endometriosis uterina, adenomyosis uteri and adenomyometritis. Adenomyosis uteri Also known more succinctly as adenomyosis (pronounced ad-den-o-mi-o- sis), 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 invades the myometrium. The myometrium may respond to this intrusion with muscular overgrowth. If an island of endometrial tissue is contained and circumscribed within the myometrium, it forms a nodule called an adenomyoma (plural: adenomyomata). Adenomyosis is made up of adeno (gland) + myo (muscle) +osis (a condition of) = a condition of glandular tissue (referring to the endometrium) in the muscle (the myometrium). Adenomyosis goes by several other names including endometriosis interna or uterina, and adenomyometritis. Adenopathy "Large or ""swollen"" lymph nodes. Synonymous with lymphadenopathy." Adenoscan Adenoscan is a prescription or over-the-counter drug which is (or once was) legal in the United States and possibly in other countries. Active ingredient(s): adenosine . Adenosine A nucleoside containing adenine as its base. Adenosine acts to dilate the coronary arteries and is employed in the adenosine thallium scan of the heart. Adenosine deaminase (ADA) An enzyme that plays a key role in salvaging purine molecules. Adenosine deaminase (ADA) deficiency A genetic (inherited) condition that results in a immune deficiency disorder called severe combined immunodeficiency disease. Adenosine deaminase is an enzyme that plays a key role in salvaging purine molecules. ADA deficiency is of special interest in the history of genetics. The first successful instance of gene therapy in humans was carried out in 1990 by Drs. W. French Anderson, R. Michael Blaese and Kenneth W. Culver who infused genetically engineered blood cells to repair ADA deficiency. Adenosine thallium scan A method of examining the heart to obtain information about the blood supply to the heart muscle. Special cameras take a series of pictures of the heart. Radioactive thallium is injected into the bloodstream and serves as a tracer. The tracer attaches to certain cells and makes them visible to the special camera. The tracer attaches to the muscle cells of the heart so the imaging camera can take pictures of the heart muscles. If an area of the heart does not receive an adequate flow of blood, the cells in the underserved area do not receive as much tracer and it appears as a darker area on the picture taken by the camera. Adenosine triphosphate The primary fuel used by cells to generate the biochemical reactions essential for life. Adenovirus One of the viruses that cause the common cold. Adensoine Adensoine is a prescription or over-the-counter drug which is (or once was) legal in the United States and possibly in other countries. Active ingredient(s): adenosine . PREVIOUS AND NEXT TERMS-------------------------------------- Adduction "Movement of a limb toward the midline of the body. The opposite of adduction is abduction. An adductor muscle pulls toward the midline of the body. For example, the adductor muscles of the legs pull the legs toward the midline of the body so the legs are closer together. From the Latin prefix ""ad"" meaning ""toward"" + ""ducere"" meaning ""to draw or lead"" = ""to draw toward.""" Adductor muscle "Any muscle that pulls a body part toward the midline. For example, the adductor muscles of the legs pull the legs toward the midline of the body so the legs are closer together. The word ""adductor"" comes from the Latin prefix ""ad"" meaning ""toward"" + ""ducere"" meaning ""to draw or lead"" = ""to draw toward."" The opposite of ""adductor"" is ""abductor."" An adductor muscle opposes an abductor muscle." Adductor spasmodic dysphonia A disorder in which sudden muscle spasms cause the vocal folds (or vocal cords) to slam together. See: spasmodic dysphonia. ADE Adverse drug event. See: Adverse reaction. Aden- See: Adeno-. Adenine (A) Adeno- "Prefix referring to a gland, as in adenoma and adenopathy. From the Greek aden meaning originally ""an acorn"" and later ""a gland"" in the form of an acorn. Before a vowel, adeno- becomes aden-, as in adenitis (inflammation of a gland)." Adenoid cystic carcinoma "A type of cancer that most often develops in the salivary glands of the head and neck. It may arise in other sites such as the skin, lacrimal gland, trachea, breast, cervix and prostate. Adenoid cystic carcinoma (ACC) has a characteristic appearance under the microscope. Abnormal ""nests"" or cords of certain cells (epithelial cells) can be seen to surround or infiltrate ducts and glandular structures. These structures are typically filled with a mucous-like material or contain abnormal fibrous membranes (hyaline membranes). ACC is an unusual tumor. It is slow-growing but relentless. It tends to be locally invasive and infiltrate the ""sheaths"" or coatings surrounding nerve fibers (perineural spaces). ACC often recurs years later at the site where the tumor first arose or it may metastasize. Unlike most carcinomas, it seldom metastasizes to nearby lymph nodes but rather to distant sites. The lung is the most common site of metastasis, with the liver second. Bone metastases indicate a poor prognosis . Treatment usually involves surgery to resect (remove) the tumor. Postoperative radiotherapy may help prevent local recurrence. Chemotherapy may slow the tumor but no chemotherapy has yet been found that is effective in destroying it." Adenoidectomy The surgical removal of the adenoids. Adenoiditis Infection of the adenoids. Adenoids and Tonsils "These celebrated structures in the back of the throat are composed of tissue similar to the lymph nodes or ""glands."" " We thank you for using the Medical Glossary to search for Adenine (A). If you have a better definition for Adenine (A) than the one presented here, please let us know by making use of the suggest a term option. This definition of Adenine (A) may be disputed by other professionals. Our attempt is to provide easy definitions on Adenine (A) and any other medical topic for the public at large.
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| adenine(a) / denine (a) / aenine (a) / adnine (a) / adeine (a) / adenne (a) / adenie (a) / adenin (a) / adenine(a) / adenine a) / adenine () / adenine (a / aadenine (a) / addenine (a) / adeenine (a) / adennine (a) / adeniine (a) / adeninne (a) / adeninee (a) / adenine (a) / adenine ((a) / adenine (aa) / adenine (a)) / qdenine (a) / wdenine (a) / sdenine (a) / xdenine (a) / zdenine (a) / aeenine (a) / arenine (a) / afenine (a) / avenine (a) / acenine (a) / axenine (a) / asenine (a) / awenine (a) / ad3nine (a) / ad4nine (a) / adrnine (a) / adfnine (a) / addnine (a) / adsnine (a) / adwnine (a) / adebine (a) / adehine (a) / adejine (a) / ademine (a) / ade ine (a) / adenne (a) / adenibe (a) / adenihe (a) / adenije (a) / adenime (a) / adeni e (a) / adenin3 (a) / adenin4 (a) / adeninr (a) / adeninf (a) / adenind (a) / adenins (a) / adeninw (a) / adenine (q) / adenine (w) / adenine (s) / adenine (x) / adenine (z) / | ||||||||||||||||