A class of compounds of the type R-M, where a C atom is joined directly to any other element except H, C, N, O, F, Cl, Br, I, or At. (Grant & Hackh's Chemical Dictionary, 5th ed)
A hard, brittle, grayish-white rare earth metal with an atomic symbol Ru, atomic number 44, and atomic weight 101.07. It is used as a catalyst and hardener for PLATINUM and PALLADIUM.
Chemicals used in agriculture. These include pesticides, fumigants, fertilizers, plant hormones, steroids, antibiotics, mycotoxins, etc.
Lists of words, usually in alphabetical order, giving information about form, pronunciation, etymology, grammar, and meaning.
The study of the physical and chemical properties of a drug and its dosage form as related to the onset, duration, and intensity of its action.
Unsaturated hydrocarbons of the type Cn-H2n, indicated by the suffix -ene. (Grant & Hackh's Chemical Dictionary, 5th ed, p408)
Hydrocarbons with at least one triple bond in the linear portion, of the general formula Cn-H2n-2.
Time period from 1801 through 1900 of the common era.
Time period from 1901 through 2000 of the common era.
Carbon monoxide (CO). A poisonous colorless, odorless, tasteless gas. It combines with hemoglobin to form carboxyhemoglobin, which has no oxygen carrying capacity. The resultant oxygen deprivation causes headache, dizziness, decreased pulse and respiratory rates, unconsciousness, and death. (From Merck Index, 11th ed)
Elements with partially filled d orbitals. They constitute groups 3-12 of the periodic table of elements.
Organic compounds composed exclusively of carbon and hydrogen forming a closed ring that may be either alicyclic or aromatic.
Compounds that provide LUBRICATION between surfaces in order to reduce FRICTION.
Organic and inorganic compounds that contain iron as an integral part of the molecule.
Board members of an institution or organization who are entrusted with the administering of funds and the directing of policy.
A cyclodecane isolated from the bark of the Pacific yew tree, TAXUS BREVIFOLIA. It stabilizes MICROTUBULES in their polymerized form leading to cell death.
That portion of the electromagnetic spectrum in the visible, ultraviolet, and infrared range.
A procedure consisting of a sequence of algebraic formulas and/or logical steps to calculate or determine a given task.
Drugs manufactured and sold with the intent to misrepresent its origin, authenticity, chemical composition, and or efficacy. Counterfeit drugs may contain inappropriate quantities of ingredients not listed on the label or package. In order to further deceive the consumer, the packaging, container, or labeling, may be inaccurate, incorrect, or fake.
Spectroscopic method of measuring the magnetic moment of elementary particles such as atomic nuclei, protons or electrons. It is employed in clinical applications such as NMR Tomography (MAGNETIC RESONANCE IMAGING).
A MOLYBDENUM requiring enzyme that catalyzes the terminal reaction in the oxidative degradation of SULFUR AMINO ACIDS with the formation of a sulfate. A deficiency of sulfite oxidase results in sulfocysteinuria.
A publication issued at stated, more or less regular, intervals.
Computer disks storing data with a maximum reduction of space and bandwidth. The compact size reduces cost of transmission and storage.
Pollutants, present in soil, which exhibit radioactivity.
Books used in the study of a subject that contain a systematic presentation of the principles and vocabulary of a subject.
A historical and cultural entity dispersed across a wide geographical area under the influence of Greek civilization, culture, and science. The Greek Empire extended from the Greek mainland and the Aegean islands from the 16th century B.C., to the Indus Valley in the 4th century under Alexander the Great, and to southern Italy and Sicily. Greek medicine began with Homeric and Aesculapian medicine and continued unbroken to Hippocrates (480-355 B.C.). The classic period of Greek medicine was 460-136 B.C. and the Graeco-Roman period, 156 B.C.-576 A.D. (From A. Castiglioni, A History of Medicine, 2d ed; from F. H. Garrison, An Introduction to the History of Medicine, 4th ed)
A metallic element with the atomic symbol Mo, atomic number 42, and atomic weight 95.94. It is an essential trace element, being a component of the enzymes xanthine oxidase, aldehyde oxidase, and nitrate reductase. (From Dorland, 27th ed)
Exclusive legal rights or privileges applied to inventions, plants, etc.
Compounds based on pyrazino[2,3-d]pyrimidine which is a pyrimidine fused to a pyrazine, containing four NITROGEN atoms.
Small molecules that are required for the catalytic function of ENZYMES. Many VITAMINS are coenzymes.
Proteins that have one or more tightly bound metal ions forming part of their structure. (Dorland, 28th ed)
Tungsten. A metallic element with the atomic symbol W, atomic number 74, and atomic weight 183.85. It is used in many manufacturing applications, including increasing the hardness, toughness, and tensile strength of steel; manufacture of filaments for incandescent light bulbs; and in contact points for automotive and electrical apparatus.
A novel composition, device, or process, independently conceived de novo or derived from a pre-existing model.
Spectrophotometric techniques by which the absorption or emmision spectra of radiation from atoms are produced and analyzed.
Liquid chromatographic techniques which feature high inlet pressures, high sensitivity, and high speed.
A group of chemical elements that are needed in minute quantities for the proper growth, development, and physiology of an organism. (From McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)
Analysis of the energy absorbed across a spectrum of x-ray energies/wavelengths to determine the chemical structure and electronic states of the absorbing medium.
A metallic element of atomic number 30 and atomic weight 65.38. It is a necessary trace element in the diet, forming an essential part of many enzymes, and playing an important role in protein synthesis and in cell division. Zinc deficiency is associated with ANEMIA, short stature, HYPOGONADISM, impaired WOUND HEALING, and geophagia. It is known by the symbol Zn.
A molecule that binds to another molecule, used especially to refer to a small molecule that binds specifically to a larger molecule, e.g., an antigen binding to an antibody, a hormone or neurotransmitter binding to a receptor, or a substrate or allosteric effector binding to an enzyme. Ligands are also molecules that donate or accept a pair of electrons to form a coordinate covalent bond with the central metal atom of a coordination complex. (From Dorland, 27th ed)
Shortened forms of written words or phrases used for brevity.
Porphyrins which are combined with a metal ion. The metal is bound equally to all four nitrogen atoms of the pyrrole rings. They possess characteristic absorption spectra which can be utilized for identification or quantitative estimation of porphyrins and porphyrin-bound compounds.
Organic compounds that have the general formula R-SO-R. They are obtained by oxidation of mercaptans (analogous to the ketones). (From Hackh's Chemical Dictionary, 4th ed)
A prodromal phase of infection with the human immunodeficiency virus (HIV). Laboratory criteria separating AIDS-related complex (ARC) from AIDS include elevated or hyperactive B-cell humoral immune responses, compared to depressed or normal antibody reactivity in AIDS; follicular or mixed hyperplasia in ARC lymph nodes, leading to lymphocyte degeneration and depletion more typical of AIDS; evolving succession of histopathological lesions such as localization of Kaposi's sarcoma, signaling the transition to the full-blown AIDS.
The voluntary portion of Medicare, known as the Supplementary Medical Insurance (SMI) Program, that includes physician's services, home health care, medical services, outpatient hospital services, and laboratory, pathology, and radiology services. All persons entitled to Medicare Part A may enroll in Medicare Part B on a monthly premium basis.
Neutral or negatively charged ligands bonded to metal cations or neutral atoms. The number of ligand atoms to which the metal center is directly bonded is the metal cation's coordination number, and this number is always greater than the regular valence or oxidation number of the metal. A coordination complex can be negative, neutral, or positively charged.
Compounds based on a seven-membered ring fused to a five-membered ring. Heat can rearrange them to NAPHTHALENES which have two fused six-membered rings. They are similar to guaiazulenes which are SESQUITERPENES with a six-membered ring fused to a five-membered ring.
Electropositive chemical elements characterized by ductility, malleability, luster, and conductance of heat and electricity. They can replace the hydrogen of an acid and form bases with hydroxyl radicals. (Grant & Hackh's Chemical Dictionary, 5th ed)