Benzopyrene Hydroxylase: A drug-metabolizing, cytochrome P-448 (P-450) enzyme which catalyzes the hydroxylation of benzopyrene to 3-hydroxybenzopyrene in the presence of reduced flavoprotein and molecular oxygen. Also acts on certain anthracene derivatives. An aspect of EC 18.104.22.168.Benzopyrenes: A class of chemicals that contain an anthracene ring with a naphthalene ring attached to it.Nikethamide: A central nervous system stimulant. It was formerly used in the treatment of barbiturate overdose but is now considered to be of no value for such purposes and may be dangerous. (From Martindale, The Extra Pharmacopoeia, 30th ed, p1229)Phenylalanine Hydroxylase: An enzyme of the oxidoreductase class that catalyzes the formation of L-TYROSINE, dihydrobiopterin, and water from L-PHENYLALANINE, tetrahydrobiopterin, and oxygen. Deficiency of this enzyme may cause PHENYLKETONURIAS and PHENYLKETONURIA, MATERNAL. EC 22.214.171.124.Steroid 21-Hydroxylase: An adrenal microsomal cytochrome P450 enzyme that catalyzes the 21-hydroxylation of steroids in the presence of molecular oxygen and NADPH-FERRIHEMOPROTEIN REDUCTASE. This enzyme, encoded by CYP21 gene, converts progesterones to precursors of adrenal steroid hormones (CORTICOSTERONE; HYDROCORTISONE). Defects in CYP21 cause congenital adrenal hyperplasia (ADRENAL HYPERPLASIA, CONGENITAL).Tryptophan Hydroxylase: An enzyme that catalyzes the hydroxylation of TRYPTOPHAN to 5-HYDROXYTRYPTOPHAN in the presence of NADPH and molecular oxygen. It is important in the biosynthesis of SEROTONIN.Tyrosine 3-Monooxygenase: An enzyme that catalyzes the conversion of L-tyrosine, tetrahydrobiopterin, and oxygen to 3,4-dihydroxy-L-phenylalanine, dihydrobiopterin, and water. EC 126.96.36.199.Mixed Function Oxygenases: Widely distributed enzymes that carry out oxidation-reduction reactions in which one atom of the oxygen molecule is incorporated into the organic substrate; the other oxygen atom is reduced and combined with hydrogen ions to form water. They are also known as monooxygenases or hydroxylases. These reactions require two substrates as reductants for each of the two oxygen atoms. There are different classes of monooxygenases depending on the type of hydrogen-providing cosubstrate (COENZYMES) required in the mixed-function oxidation.Procollagen-Proline Dioxygenase: A mixed-function oxygenase that catalyzes the hydroxylation of a prolyl-glycyl containing peptide, usually in PROTOCOLLAGEN, to a hydroxyprolylglycyl-containing-peptide. The enzyme utilizes molecular OXYGEN with a concomitant oxidative decarboxylation of 2-oxoglutarate to SUCCINATE. The enzyme occurs as a tetramer of two alpha and two beta subunits. The beta subunit of procollagen-proline dioxygenase is identical to the enzyme PROTEIN DISULFIDE-ISOMERASES.Bixaceae: A plant family of the order Violales, subclass Dilleniidae, class Magnoliopsida. Bixa contains bixin. Cochlospermum contains arjunolic acid and gum kondagogu (POLYSACCHARIDES).Cytochrome P-450 Enzyme System: A superfamily of hundreds of closely related HEMEPROTEINS found throughout the phylogenetic spectrum, from animals, plants, fungi, to bacteria. They include numerous complex monooxygenases (MIXED FUNCTION OXYGENASES). In animals, these P-450 enzymes serve two major functions: (1) biosynthesis of steroids, fatty acids, and bile acids; (2) metabolism of endogenous and a wide variety of exogenous substrates, such as toxins and drugs (BIOTRANSFORMATION). They are classified, according to their sequence similarities rather than functions, into CYP gene families (>40% homology) and subfamilies (>59% homology). For example, enzymes from the CYP1, CYP2, and CYP3 gene families are responsible for most drug metabolism.Metyrapone: An inhibitor of the enzyme STEROID 11-BETA-MONOOXYGENASE. It is used as a test of the feedback hypothalamic-pituitary mechanism in the diagnosis of CUSHING SYNDROME.Steroids: A group of polycyclic compounds closely related biochemically to TERPENES. They include cholesterol, numerous hormones, precursors of certain vitamins, bile acids, alcohols (STEROLS), and certain natural drugs and poisons. Steroids have a common nucleus, a fused, reduced 17-carbon atom ring system, cyclopentanoperhydrophenanthrene. Most steroids also have two methyl groups and an aliphatic side-chain attached to the nucleus. (From Hawley's Condensed Chemical Dictionary, 11th ed)Benzoflavones: Organic compounds containing a BENZENE ring attached to a flavone group. Some of these are potent arylhydrocarbon hydroxylase inhibitors. They may also inhibit the binding of NUCLEIC ACIDS to BENZOPYRENES and related compounds. The designation includes all isomers; the 7,8-isomer is most frequently encountered.Methylcholanthrene: A carcinogen that is often used in experimental cancer studies.Physicians: Individuals licensed to practice medicine.Internet: A loose confederation of computer communication networks around the world. The networks that make up the Internet are connected through several backbone networks. The Internet grew out of the US Government ARPAnet project and was designed to facilitate information exchange.Lawyers: Persons whose profession is to give legal advice and assistance to clients and represent them in legal matters. (American Heritage Dictionary, 3d ed)Child Advocacy: Promotion and protection of the rights of children; frequently through a legal process.Questionnaires: Predetermined sets of questions used to collect data - clinical data, social status, occupational group, etc. The term is often applied to a self-completed survey instrument.Attitude of Health Personnel: Attitudes of personnel toward their patients, other professionals, toward the medical care system, etc.Bites, Human: Bites inflicted by humans.Benzofurans: Compounds that contain a BENZENE ring fused to a furan ring.Dictionaries, MedicalCoal Tar: A by-product of the destructive distillation of coal used as a topical antieczematic. It is an antipruritic and keratoplastic agent used also in the treatment of psoriasis and other skin conditions. Occupational exposure to soots, tars, and certain mineral oils is known to be carcinogenic according to the Fourth Annual Report on Carcinogens (NTP 85-002, 1985) (Merck Index, 11th ed).Dictionaries as Topic: Lists of words, usually in alphabetical order, giving information about form, pronunciation, etymology, grammar, and meaning.Ethers, Cyclic: Compounds of the general formula R-O-R arranged in a ring or crown formation.Khellin: A vasodilator that also has bronchodilatory action. It has been employed in the treatment of angina pectoris, in the treatment of asthma, and in conjunction with ultraviolet light A, has been tried in the treatment of vitiligo. (From Martindale, The Extra Pharmacopoeia, 30th ed, p1024)Psoralea: A plant genus of the family FABACEAE that is a source of psoralen (FICUSIN).Abbreviations as Topic: Shortened forms of written words or phrases used for brevity.Dictionaries, ChemicalTerminology as Topic: The terms, expressions, designations, or symbols used in a particular science, discipline, or specialized subject area.DictionaryNatural Language Processing: Computer processing of a language with rules that reflect and describe current usage rather than prescribed usage.Receptors, CCR: Chemokine receptors that are specific for CC CHEMOKINES.Databases, Factual: Extensive collections, reputedly complete, of facts and data garnered from material of a specialized subject area and made available for analysis and application. The collection can be automated by various contemporary methods for retrieval. The concept should be differentiated from DATABASES, BIBLIOGRAPHIC which is restricted to collections of bibliographic references.Chemokine CCL19: A CC-type chemokine with specificity for CCR7 RECEPTORS. It has activity towards T LYMPHOCYTES and B LYMPHOCYTES.Directories as Topic: Lists of persons or organizations, systematically arranged, usually in alphabetic or classed order, giving address, affiliations, etc., for individuals, and giving address, officers, functions, and similar data for organizations. (ALA Glossary of Library and Information Science, 1983)Trypanosoma brucei brucei: A hemoflagellate subspecies of parasitic protozoa that causes nagana in domestic and game animals in Africa. It apparently does not infect humans. It is transmitted by bites of tsetse flies (Glossina).Computer Communication Networks: A system containing any combination of computers, computer terminals, printers, audio or visual display devices, or telephones interconnected by telecommunications equipment or cables: used to transmit or receive information. (Random House Unabridged Dictionary, 2d ed)Semaphorin-3A: The prototypical and most well-studied member of the semaphorin family. Semaphorin-3A is an axon-repulsive guidance cue for migrating neurons in the developing nervous system. It has so far been found only in vertebrates, and binds to NEUROPILIN-1/plexin complex receptors on growth cones. Like other class 3 semaphorins, it is a secreted protein.beta Carotene: A carotenoid that is a precursor of VITAMIN A. It is administered to reduce the severity of photosensitivity reactions in patients with erythropoietic protoporphyria (PORPHYRIA, ERYTHROPOIETIC). (From Reynolds JEF(Ed): Martindale: The Extra Pharmacopoeia (electronic version). Micromedex, Inc, Engewood, CO, 1995.)Petroselinum: A plant genus of the family APIACEAE used for flavoring food.Chlorophyll: Porphyrin derivatives containing magnesium that act to convert light energy in photosynthetic organisms.Citrus: A plant genus of the family RUTACEAE. They bear the familiar citrus fruits including oranges, grapefruit, lemons, and limes. There are many hybrids which makes the nomenclature confusing.Nutritive Value: An indication of the contribution of a food to the nutrient content of the diet. This value depends on the quantity of a food which is digested and absorbed and the amounts of the essential nutrients (protein, fat, carbohydrate, minerals, vitamins) which it contains. This value can be affected by soil and growing conditions, handling and storage, and processing.CresolsApiaceae: A large plant family in the order Apiales, also known as Umbelliferae. Most are aromatic herbs with alternate, feather-divided leaves that are sheathed at the base. The flowers often form a conspicuous flat-topped umbel. Each small individual flower is usually bisexual, with five sepals, five petals, and an enlarged disk at the base of the style. The fruits are ridged and are composed of two parts that split open at maturity.