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)
The science concerned with problems of radiation protection relevant to reducing or preventing radiation exposure, and the effects of ionizing radiation on humans and their environment.
A subspecialty of medical oncology and radiology concerned with the radiotherapy of cancer.
Radiation protection, also known as radiation safety, is the science and practice of protecting people and the environment from harmful ionizing radiation exposure while allowing for the safe medical, industrial, and research uses of such radiation.
The measurement of radiation by photography, as in x-ray film and film badge, by Geiger-Mueller tube, and by SCINTILLATION COUNTING.
Information systems, usually computer-assisted, designed to store, manipulate, and retrieve information for planning, organizing, directing, and controlling administrative activities associated with the provision and utilization of radiology services and facilities.
Relating to the size of solids.
The amount of radiation energy that is deposited in a unit mass of material, such as tissues of plants or animal. In RADIOTHERAPY, radiation dosage is expressed in gray units (Gy). In RADIOLOGIC HEALTH, the dosage is expressed by the product of absorbed dose (Gy) and quality factor (a function of linear energy transfer), and is called radiation dose equivalent in sievert units (Sv).
The infective system of a virus, composed of the viral genome, a protein core, and a protein coat called a capsid, which may be naked or enclosed in a lipoprotein envelope called the peplos.
Microscopy using an electron beam, instead of light, to visualize the sample, thereby allowing much greater magnification. The interactions of ELECTRONS with specimens are used to provide information about the fine structure of that specimen. In TRANSMISSION ELECTRON MICROSCOPY the reactions of the electrons that are transmitted through the specimen are imaged. In SCANNING ELECTRON MICROSCOPY an electron beam falls at a non-normal angle on the specimen and the image is derived from the reactions occurring above the plane of the specimen.
A cytosolic ribonucleoprotein complex that acts to induce elongation arrest of nascent presecretory and membrane proteins until the ribosome becomes associated with the rough endoplasmic reticulum. It consists of a 7S RNA and at least six polypeptide subunits (relative molecular masses 9, 14, 19, 54, 68, and 72K).
Nanometer-sized particles that are nanoscale in three dimensions. They include nanocrystaline materials; NANOCAPSULES; METAL NANOPARTICLES; DENDRIMERS, and QUANTUM DOTS. The uses of nanoparticles include DRUG DELIVERY SYSTEMS and cancer targeting and imaging.
The assembly of VIRAL STRUCTURAL PROTEINS and nucleic acid (VIRAL DNA or VIRAL RNA) to form a VIRUS PARTICLE.
Colloids with a gaseous dispersing phase and either liquid (fog) or solid (smoke) dispersed phase; used in fumigation or in inhalation therapy; may contain propellant agents.
Vaccines using supra-molecular structures composed of multiple copies of recombinantly expressed viral structural proteins. They are often antigentically indistinguishable from the virus from which they were derived.
The various filaments, granules, tubules or other inclusions within mitochondria.
Particles of any solid substance, generally under 30 microns in size, often noted as PM30. There is special concern with PM1 which can get down to PULMONARY ALVEOLI and induce MACROPHAGE ACTIVATION and PHAGOCYTOSIS leading to FOREIGN BODY REACTION and LUNG DISEASES.
Preparation for electron microscopy of minute replicas of exposed surfaces of the cell which have been ruptured in the frozen state. The specimen is frozen, then cleaved under high vacuum at the same temperature. The exposed surface is shadowed with carbon and platinum and coated with carbon to obtain a carbon replica.
Established cell cultures that have the potential to propagate indefinitely.
The outer protein protective shell of a virus, which protects the viral nucleic acid.
Small uniformly-sized spherical particles, of micrometer dimensions, frequently labeled with radioisotopes or various reagents acting as tags or markers.
Separation of particles according to density by employing a gradient of varying densities. At equilibrium each particle settles in the gradient at a point equal to its density. (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)
Positively charged particles composed of two protons and two NEUTRONS, i.e. equivalent to HELIUM nuclei, which are emitted during disintegration of heavy ISOTOPES. Alpha rays have very strong ionizing power, but weak penetrability.
A milky, product excreted from the latex canals of a variety of plant species that contain cauotchouc. Latex is composed of 25-35% caoutchouc, 60-75% water, 2% protein, 2% resin, 1.5% sugar & 1% ash. RUBBER is made by the removal of water from latex.(From Concise Encyclopedia Biochemistry and Molecular Biology, 3rd ed). Hevein proteins are responsible for LATEX HYPERSENSITIVITY. Latexes are used as inert vehicles to carry antibodies or antigens in LATEX FIXATION TESTS.
Proteins that form the CAPSID of VIRUSES.
Viruses which lack a complete genome so that they cannot completely replicate or cannot form a protein coat. Some are host-dependent defectives, meaning they can replicate only in cell systems which provide the particular genetic function which they lack. Others, called SATELLITE VIRUSES, are able to replicate only when their genetic defect is complemented by a helper virus.
Two-phase systems in which one is uniformly dispersed in another as particles small enough so they cannot be filtered or will not settle out. The dispersing or continuous phase or medium envelops the particles of the discontinuous phase. All three states of matter can form colloids among each other.
An area showing altered staining behavior in the nucleus or cytoplasm of a virus-infected cell. Some inclusion bodies represent "virus factories" in which viral nucleic acid or protein is being synthesized; others are merely artifacts of fixation and staining. One example, Negri bodies, are found in the cytoplasm or processes of nerve cells in animals that have died from rabies.
Transparent, tasteless crystals found in nature as agate, amethyst, chalcedony, cristobalite, flint, sand, QUARTZ, and tridymite. The compound is insoluble in water or acids except hydrofluoric acid.
Any substance in the air which could, if present in high enough concentration, harm humans, animals, vegetation or material. Substances include GASES; PARTICULATE MATTER; and volatile ORGANIC CHEMICALS.
Polymerized forms of styrene used as a biocompatible material, especially in dentistry. They are thermoplastic and are used as insulators, for injection molding and casting, as sheets, plates, rods, rigid forms and beads.
The exposure to potentially harmful chemical, physical, or biological agents by inhaling them.
Gases, fumes, vapors, and odors escaping from the cylinders of a gasoline or diesel internal-combustion engine. (From McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed & Random House Unabridged Dictionary, 2d ed)
Substances made up of an aggregation of small particles, as that obtained by grinding or trituration of a solid drug. In pharmacy it is a form in which substances are administered. (From Dorland, 28th ed)
Complexes of RNA-binding proteins with ribonucleic acids (RNA).
A class of lipoproteins of small size (4-13 nm) and dense (greater than 1.063 g/ml) particles. HDL lipoproteins, synthesized in the liver without a lipid core, accumulate cholesterol esters from peripheral tissues and transport them to the liver for re-utilization or elimination from the body (the reverse cholesterol transport). Their major protein component is APOLIPOPROTEIN A-I. HDL also shuttle APOLIPOPROTEINS C and APOLIPOPROTEINS E to and from triglyceride-rich lipoproteins during their catabolism. HDL plasma level has been inversely correlated with the risk of cardiovascular diseases.
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 process of intracellular viral multiplication, consisting of the synthesis of PROTEINS; NUCLEIC ACIDS; and sometimes LIPIDS, and their assembly into a new infectious particle.
Microscopy in which the object is examined directly by an electron beam scanning the specimen point-by-point. The image is constructed by detecting the products of specimen interactions that are projected above the plane of the sample, such as backscattered electrons. Although SCANNING TRANSMISSION ELECTRON MICROSCOPY also scans the specimen point by point with the electron beam, the image is constructed by detecting the electrons, or their interaction products that are transmitted through the sample plane, so that is a form of TRANSMISSION ELECTRON MICROSCOPY.
Semi-synthetic complex derived from nucleic-acid free viral particles. They are essentially reconstituted viral coats, where the infectious nucleocapsid is replaced by a compound of choice. Virosomes retain their fusogenic activity and thus deliver the incorporated compound (antigens, drugs, genes) inside the target cell. They can be used for vaccines (VACCINES, VIROSOME), drug delivery, or gene transfer.
Proteins found in any species of virus.
Celestial bodies orbiting around the sun or other stars.
Aggregates of matter in outer space, such as stars, planets, comets, etc. and the properties and processes they undergo.
The science concerned with celestial bodies and the observation and interpretation of the radiation received in the vicinity of the earth from the component parts of the universe (McGraw Hill Dictionary of Scientific and Technical Terms, 5th ed)
'Printing' in a medical context refers to the temporary or permanent transfer of ink from a substrate to the skin, often used for identification purposes, monitoring medical conditions, or as a form of temporary decoration.
Large bodies consisting of self-luminous gas held together by their own gravity. (From McGraw Hill Dictionary of Scientific and Technical Terms, 6th ed)
Large aggregates of CELESTIAL STARS; COSMIC DUST; and gas. (From McGraw Hill Dictionary of Scientific and Technical Terms, 6th ed)
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)