Stable xenon atoms that have the same atomic number as the element xenon, but differ in atomic weight. Xe-124, 126, 128-131, 134, and 136 are stable xenon isotopes.
A noble gas with the atomic symbol Xe, atomic number 54, and atomic weight 131.30. It is found in the earth's atmosphere and has been used as an anesthetic.
Atomic species differing in mass number but having the same atomic number. (Grant & Hackh's Chemical Dictionary, 5th ed)
Techniques for labeling a substance with a stable or radioactive isotope. It is not used for articles involving labeled substances unless the methods of labeling are substantively discussed. Tracers that may be labeled include chemical substances, cells, or microorganisms.
Unstable isotopes of xenon that decay or disintegrate emitting radiation. Xe atoms with atomic weights 121-123, 125, 127, 133, 135, 137-145 are radioactive xenon isotopes.
Stable nitrogen atoms that have the same atomic number as the element nitrogen, but differ in atomic weight. N-15 is a stable nitrogen isotope.
Stable oxygen atoms that have the same atomic number as the element oxygen, but differ in atomic weight. O-17 and 18 are stable oxygen isotopes.
Stable carbon atoms that have the same atomic number as the element carbon, but differ in atomic weight. C-13 is a stable carbon isotope.
Gases or volatile liquids that vary in the rate at which they induce anesthesia; potency; the degree of circulation, respiratory, or neuromuscular depression they produce; and analgesic effects. Inhalation anesthetics have advantages over intravenous agents in that the depth of anesthesia can be changed rapidly by altering the inhaled concentration. Because of their rapid elimination, any postoperative respiratory depression is of relatively short duration. (From AMA Drug Evaluations Annual, 1994, p173)
Stable zinc atoms that have the same atomic number as the element zinc, but differ in atomic weight. Zn-66-68, and 70 are stable zinc isotopes.
Stable sulfur atoms that have the same atomic number as the element sulfur, but differ in atomic weight. S-33, 34, and 36 are stable sulfur isotopes.
Deuterium. The stable isotope of hydrogen. It has one neutron and one proton in the nucleus.
Stable iron atoms that have the same atomic number as the element iron, but differ in atomic weight. Fe-54, 57, and 58 are stable iron isotopes.
Nitrogen oxide (N2O). A colorless, odorless gas that is used as an anesthetic and analgesic. High concentrations cause a narcotic effect and may replace oxygen, causing death by asphyxia. It is also used as a food aerosol in the preparation of whipping cream.
Argon. A noble gas with the atomic symbol Ar, atomic number 18, and atomic weight 39.948. It is used in fluorescent tubes and wherever an inert atmosphere is desired and nitrogen cannot be used.
Stable strontium atoms that have the same atomic number as the element strontium, but differ in the atomic weight. Sr-84, 86, 87, and 88 are the stable strontium isotopes.
Works containing information articles on subjects in every field of knowledge, usually arranged in alphabetical order, or a similar work limited to a special field or subject. (From The ALA Glossary of Library and Information Science, 1983)
Graphic representations, especially of the face, of real persons, usually posed, living or dead. (From Thesaurus for Graphic Materials II, p540, 1995)
INSECTS of the order Coleoptera, containing over 350,000 species in 150 families. They possess hard bodies and their mouthparts are adapted for chewing.
A plant family of the order Lecythidales, subclass Dilleniidae, class Magnoliopsida.
DNA sequences encoding RIBOSOMAL RNA and the segments of DNA separating the individual ribosomal RNA genes, referred to as RIBOSOMAL SPACER DNA.
The outer layer of the woody parts of plants.
The spontaneous transformation of a nuclide into one or more different nuclides, accompanied by either the emission of particles from the nucleus, nuclear capture or ejection of orbital electrons, or fission. (McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)
The fourth planet in order from the sun. Its two natural satellites are Deimos and Phobos. It is one of the four inner or terrestrial planets of the solar system.
A family of fungi, order POLYPORALES, found on decaying wood.
Unstable isotopes of nitrogen that decay or disintegrate emitting radiation. N atoms with atomic weights 12, 13, 16, 17, and 18 are radioactive nitrogen isotopes.
A set of twelve curved bones which connect to the vertebral column posteriorly, and terminate anteriorly as costal cartilage. Together, they form a protective cage around the internal thoracic organs.
External decompression applied to the lower body. It is used to study orthostatic intolerance and the effects of gravitation and acceleration, to produce simulated hemorrhage in physiologic research, to assess cardiovascular function, and to reduce abdominal stress during childbirth.
The administration of drugs by the respiratory route. It includes insufflation into the respiratory tract.
A type of stress exerted uniformly in all directions. Its measure is the force exerted per unit area. (McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)
NATIONAL LIBRARY OF MEDICINE service for health professionals and consumers. It links extensive information from the National Institutes of Health and other reviewed sources of information on specific diseases and conditions.
A funnel-shaped fibromuscular tube that conducts food to the ESOPHAGUS, and air to the LARYNX and LUNGS. It is located posterior to the NASAL CAVITY; ORAL CAVITY; and LARYNX, and extends from the SKULL BASE to the inferior border of the CRICOID CARTILAGE anteriorly and to the inferior border of the C6 vertebra posteriorly. It is divided into the NASOPHARYNX; OROPHARYNX; and HYPOPHARYNX (laryngopharynx).
Any solid objects moving in interplanetary space that are smaller than a planet or asteroid but larger than a molecule. Meteorites are any meteoroid that has fallen to a planetary surface. (From McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)
The group of celestial bodies, including the EARTH, orbiting around and gravitationally bound by the sun. It includes eight planets, one minor planet, and 34 natural satellites, more than 1,000 observed comets, and thousands of lesser bodies known as MINOR PLANETS (asteroids) and METEOROIDS. (From Academic American Encyclopedia, 1983)
Isotopes that exhibit radioactivity and undergo radioactive decay. (From Grant & Hackh's Chemical Dictionary, 5th ed & McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)
Finely divided solid matter with particle sizes smaller than a micrometeorite, thus with diameters much smaller than a millimeter, moving in interplanetary space. (NASA Thesaurus, 1994)
The study of those aspects of energy and matter in terms of elementary principles and laws. (From McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)
A family of alicyclic hydrocarbons containing an amine group with the general formula R-C6H10NH2.
A group of compounds with three aromatic rings joined in linear arrangement.
Elements that constitute group 18 (formerly the zero group) of the periodic table. They are gases that generally do not react chemically.
A family of delayed rectifier voltage-gated potassium channels that share homology with their founding member, KCNQ1 PROTEIN. KCNQ potassium channels have been implicated in a variety of diseases including LONG QT SYNDROME; DEAFNESS; and EPILEPSY.
A noble gas that is found in the atmosphere. It has the atomic symbol Kr, atomic number 36, atomic weight 83.80, and has been used in electric bulbs.
The circulation of blood through the BLOOD VESSELS of the BRAIN.
The ratio of alveolar ventilation to simultaneous alveolar capillary blood flow in any part of the lung. (Stedman, 25th ed)
One of the CARBONIC ANHYDRASE INHIBITORS that is sometimes effective against absence seizures. It is sometimes useful also as an adjunct in the treatment of tonic-clonic, myoclonic, and atonic seizures, particularly in women whose seizures occur or are exacerbated at specific times in the menstrual cycle. However, its usefulness is transient often because of rapid development of tolerance. Its antiepileptic effect may be due to its inhibitory effect on brain carbonic anhydrase, which leads to an increased transneuronal chloride gradient, increased chloride current, and increased inhibition. (From Smith and Reynard, Textbook of Pharmacology, 1991, p337)
Nuclear reaction in which the nucleus of a heavy atom such as uranium or plutonium is split into two approximately equal parts by a neutron, charged particle, or photon.
The forces and principles of action of matter and energy.
A republic in west equatorial Africa, south of CAMEROON and west of the CONGO. Its capital is Libreville.
Theoretical representations that simulate the behavior or activity of chemical processes or phenomena; includes the use of mathematical equations, computers, and other electronic equipment.
Descriptions of specific amino acid, carbohydrate, or nucleotide sequences which have appeared in the published literature and/or are deposited in and maintained by databanks such as GENBANK, European Molecular Biology Laboratory (EMBL), National Biomedical Research Foundation (NBRF), or other sequence repositories.
The rate dynamics in chemical or physical systems.
The order of amino acids as they occur in a polypeptide chain. This is referred to as the primary structure of proteins. It is of fundamental importance in determining PROTEIN CONFORMATION.