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Microscopy: The use of instrumentation and techniques for visualizing material and details that cannot be seen by the unaided eye. It is usually done by enlarging images, transmitted by light or electron beams, with optical or magnetic lenses that magnify the entire image field. With scanning microscopy, images are generated by collecting output from the specimen in a point-by-point fashion, on a magnified scale, as it is scanned by a narrow beam of light or electrons, a laser, a conductive probe, or a topographical probe.Video Games: A form of interactive entertainment in which the player controls electronically generated images that appear on a video display screen. This includes video games played in the home on special machines or home computers, and those played in arcades.Microscopy, Electron: 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.Microscopy, Electron, Scanning: 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.Microscopy, Confocal: A light microscopic technique in which only a small spot is illuminated and observed at a time. An image is constructed through point-by-point scanning of the field in this manner. Light sources may be conventional or laser, and fluorescence or transmitted observations are possible.Microscopy, Video: Microscopy in which television cameras are used to brighten magnified images that are otherwise too dark to be seen with the naked eye. It is used frequently in TELEPATHOLOGY.Microscopy, Fluorescence: Microscopy of specimens stained with fluorescent dye (usually fluorescein isothiocyanate) or of naturally fluorescent materials, which emit light when exposed to ultraviolet or blue light. Immunofluorescence microscopy utilizes antibodies that are labeled with fluorescent dye.Videotape Recording: Recording of visual and sometimes sound signals on magnetic tape.Microscopy, Atomic Force: A type of scanning probe microscopy in which a probe systematically rides across the surface of a sample being scanned in a raster pattern. The vertical position is recorded as a spring attached to the probe rises and falls in response to peaks and valleys on the surface. These deflections produce a topographic map of the sample.Microscopy, Electron, Transmission: Electron microscopy in which the ELECTRONS or their reaction products that pass down through the specimen are imaged below the plane of the specimen.Microscopy, Immunoelectron: Microscopy in which the samples are first stained immunocytochemically and then examined using an electron microscope. Immunoelectron microscopy is used extensively in diagnostic virology as part of very sensitive immunoassays.Microscopy, Fluorescence, Multiphoton: Fluorescence microscopy utilizing multiple low-energy photons to produce the excitation event of the fluorophore. Multiphoton microscopes have a simplified optical path in the emission side due to the lack of an emission pinhole, which is necessary with normal confocal microscopes. Ultimately this allows spatial isolation of the excitation event, enabling deeper imaging into optically thick tissue, while restricting photobleaching and phototoxicity to the area being imaged.Cryoelectron Microscopy: Electron microscopy involving rapid freezing of the samples. The imaging of frozen-hydrated molecules and organelles permits the best possible resolution closest to the living state, free of chemical fixatives or stains.Microscopy, Scanning Tunneling: A type of scanning probe microscopy in which a very sharp conducting needle is swept just a few angstroms above the surface of a sample. The tiny tunneling current that flows between the sample and the needle tip is measured, and from this are produced three-dimensional topographs. Due to the poor electron conductivity of most biological samples, thin metal coatings are deposited on the sample.Microscopy, Interference: The science and application of a double-beam transmission interference microscope in which the illuminating light beam is split into two paths. One beam passes through the specimen while the other beam reflects off a reference mirror before joining and interfering with the other. The observed optical path difference between the two beams can be measured and used to discriminate minute differences in thickness and refraction of non-stained transparent specimens, such as living cells in culture.Microscopy, Polarization: Microscopy using polarized light in which phenomena due to the preferential orientation of optical properties with respect to the vibration plane of the polarized light are made visible and correlated parameters are made measurable.Microscopy, Phase-Contrast: A form of interference microscopy in which variations of the refracting index in the object are converted into variations of intensity in the image. This is achieved by the action of a phase plate.Microscopy, Electron, Scanning Transmission: A type of TRANSMISSION ELECTRON MICROSCOPY in which the object is examined directly by an extremely narrow electron beam scanning the specimen point-by-point and using the reactions of the electrons that are transmitted through the specimen to create the image. It should not be confused with SCANNING ELECTRON MICROSCOPY.Microscopy, Scanning Probe: Scanning microscopy in which a very sharp probe is employed in close proximity to a surface, exploiting a particular surface-related property. When this property is local topography, the method is atomic force microscopy (MICROSCOPY, ATOMIC FORCE), and when it is local conductivity, the method is scanning tunneling microscopy (MICROSCOPY, SCANNING TUNNELING).Image Processing, Computer-Assisted: A technique of inputting two-dimensional images into a computer and then enhancing or analyzing the imagery into a form that is more useful to the human observer.Fluorescent Dyes: Agents that emit light after excitation by light. The wave length of the emitted light is usually longer than that of the incident light. Fluorochromes are substances that cause fluorescence in other substances, i.e., dyes used to mark or label other compounds with fluorescent tags.Staining and Labeling: The marking of biological material with a dye or other reagent for the purpose of identifying and quantitating components of tissues, cells or their extracts.Microscopy, Acoustic: A scientific tool based on ULTRASONOGRAPHY and used not only for the observation of microstructure in metalwork but also in living tissue. In biomedical application, the acoustic propagation speed in normal and abnormal tissues can be quantified to distinguish their tissue elasticity and other properties.Time Factors: Elements of limited time intervals, contributing to particular results or situations.Cell Membrane: The lipid- and protein-containing, selectively permeable membrane that surrounds the cytoplasm in prokaryotic and eukaryotic cells.Videoconferencing: Communications via an interactive conference between two or more participants at different sites, using computer networks (COMPUTER COMMUNICATION NETWORKS) or other telecommunication links to transmit audio, video, and data.Fluorescent Antibody Technique: Test for tissue antigen using either a direct method, by conjugation of antibody with fluorescent dye (FLUORESCENT ANTIBODY TECHNIQUE, DIRECT) or an indirect method, by formation of antigen-antibody complex which is then labeled with fluorescein-conjugated anti-immunoglobulin antibody (FLUORESCENT ANTIBODY TECHNIQUE, INDIRECT). The tissue is then examined by fluorescence microscopy.Cells, Cultured: Cells propagated in vitro in special media conducive to their growth. Cultured cells are used to study developmental, morphologic, metabolic, physiologic, and genetic processes, among others.Green Fluorescent Proteins: Protein analogs and derivatives of the Aequorea victoria green fluorescent protein that emit light (FLUORESCENCE) when excited with ULTRAVIOLET RAYS. They are used in REPORTER GENES in doing GENETIC TECHNIQUES. Numerous mutants have been made to emit other colors or be sensitive to pH.Imaging, Three-Dimensional: The process of generating three-dimensional images by electronic, photographic, or other methods. For example, three-dimensional images can be generated by assembling multiple tomographic images with the aid of a computer, while photographic 3-D images (HOLOGRAPHY) can be made by exposing film to the interference pattern created when two laser light sources shine on an object.Television: The transmission and reproduction of transient images of fixed or moving objects. An electronic system of transmitting such images together with sound over a wire or through space by apparatus that converts light and sound into electrical waves and reconverts them into visible light rays and audible sound. (From Webster, 3rd ed)Cell Line: Established cell cultures that have the potential to propagate indefinitely.Surface Properties: Characteristics or attributes of the outer boundaries of objects, including molecules.Immunohistochemistry: Histochemical localization of immunoreactive substances using labeled antibodies as reagents.Equipment Design: Methods of creating machines and devices.Luminescent Proteins: Proteins which are involved in the phenomenon of light emission in living systems. Included are the "enzymatic" and "non-enzymatic" types of system with or without the presence of oxygen or co-factors.Actins: Filamentous proteins that are the main constituent of the thin filaments of muscle fibers. The filaments (known also as filamentous or F-actin) can be dissociated into their globular subunits; each subunit is composed of a single polypeptide 375 amino acids long. This is known as globular or G-actin. In conjunction with MYOSINS, actin is responsible for the contraction and relaxation of muscle.Motion Pictures as Topic: The art, technique, or business of producing motion pictures for entertainment, propaganda, or instruction.Molecular Sequence Data: 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.Multimedia: Materials, frequently computer applications, that combine some or all of text, sound, graphics, animation, and video into integrated packages. (Thesaurus of ERIC Descriptors, 1994)Audiovisual Aids: Auditory and visual instructional materials.Rabbits: The species Oryctolagus cuniculus, in the family Leporidae, order LAGOMORPHA. Rabbits are born in burrows, furless, and with eyes and ears closed. In contrast with HARES, rabbits have 22 chromosome pairs.Freeze Fracturing: 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.Cytoplasm: The part of a cell that contains the CYTOSOL and small structures excluding the CELL NUCLEUS; MITOCHONDRIA; and large VACUOLES. (Glick, Glossary of Biochemistry and Molecular Biology, 1990)Microtubules: Slender, cylindrical filaments found in the cytoskeleton of plant and animal cells. They are composed of the protein TUBULIN and are influenced by TUBULIN MODULATORS.Computer Terminals: Input/output devices designed to receive data in an environment associated with the job to be performed, and capable of transmitting entries to, and obtaining output from, the system of which it is a part. (Computer Dictionary, 4th ed.)Lasers: An optical source that emits photons in a coherent beam. Light Amplification by Stimulated Emission of Radiation (LASER) is brought about using devices that transform light of varying frequencies into a single intense, nearly nondivergent beam of monochromatic radiation. Lasers operate in the infrared, visible, ultraviolet, or X-ray regions of the spectrum.Video-Assisted Surgery: Endoscopic surgical procedures performed with visualization via video transmission. When real-time video is combined interactively with prior CT scans or MRI images, this is called image-guided surgery (see SURGERY, COMPUTER-ASSISTED).Particle Size: Relating to the size of solids.Time-Lapse Imaging: Recording serial images of a process at regular intervals spaced out over a longer period of time than the time in which the recordings will be played back.Cell Nucleus: Within a eukaryotic cell, a membrane-limited body which contains chromosomes and one or more nucleoli (CELL NUCLEOLUS). The nuclear membrane consists of a double unit-type membrane which is perforated by a number of pores; the outermost membrane is continuous with the ENDOPLASMIC RETICULUM. A cell may contain more than one nucleus. (From Singleton & Sainsbury, Dictionary of Microbiology and Molecular Biology, 2d ed)Biomechanical Phenomena: The properties, processes, and behavior of biological systems under the action of mechanical forces.Gold: A yellow metallic element with the atomic symbol Au, atomic number 79, and atomic weight 197. It is used in jewelry, goldplating of other metals, as currency, and in dental restoration. Many of its clinical applications, such as ANTIRHEUMATIC AGENTS, are in the form of its salts.Cytoskeleton: The network of filaments, tubules, and interconnecting filamentous bridges which give shape, structure, and organization to the cytoplasm.Models, Biological: Theoretical representations that simulate the behavior or activity of biological processes or diseases. For disease models in living animals, DISEASE MODELS, ANIMAL is available. Biological models include the use of mathematical equations, computers, and other electronic equipment.Reproducibility of Results: The statistical reproducibility of measurements (often in a clinical context), including the testing of instrumentation or techniques to obtain reproducible results. The concept includes reproducibility of physiological measurements, which may be used to develop rules to assess probability or prognosis, or response to a stimulus; reproducibility of occurrence of a condition; and reproducibility of experimental results.Nanotechnology: The development and use of techniques to study physical phenomena and construct structures in the nanoscale size range or smaller.Microscopy, Ultraviolet: Microscopy in which the image is formed by ultraviolet radiation and is displayed and recorded by means of photographic film.Membrane Proteins: Proteins which are found in membranes including cellular and intracellular membranes. They consist of two types, peripheral and integral proteins. They include most membrane-associated enzymes, antigenic proteins, transport proteins, and drug, hormone, and lectin receptors.Photons: Discrete concentrations of energy, apparently massless elementary particles, that move at the speed of light. They are the unit or quantum of electromagnetic radiation. Photons are emitted when electrons move from one energy state to another. (From Hawley's Condensed Chemical Dictionary, 11th ed)Sensitivity and Specificity: Binary classification measures to assess test results. Sensitivity or recall rate is the proportion of true positives. Specificity is the probability of correctly determining the absence of a condition. (From Last, Dictionary of Epidemiology, 2d ed)Optics and Photonics: A specialized field of physics and engineering involved in studying the behavior and properties of light and the technology of analyzing, generating, transmitting, and manipulating ELECTROMAGNETIC RADIATION in the visible, infrared, and ultraviolet range.Microtomy: The technique of using a microtome to cut thin or ultrathin sections of tissues embedded in a supporting substance. The microtome is an instrument that hold a steel, glass or diamond knife in clamps at an angle to the blocks of prepared tissues, which it cuts in sections of equal thickness.Telecommunications: Transmission of information over distances via electronic means.Tissue Embedding: The technique of placing cells or tissue in a supporting medium so that thin sections can be cut using a microtome. The medium can be paraffin wax (PARAFFIN EMBEDDING) or plastics (PLASTIC EMBEDDING) such as epoxy resins.Histocytochemistry: Study of intracellular distribution of chemicals, reaction sites, enzymes, etc., by means of staining reactions, radioactive isotope uptake, selective metal distribution in electron microscopy, or other methods.Amino Acid Sequence: 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.Holography: The recording of images in three-dimensional form on a photographic film by exposing it to a laser beam reflected from the object under study.Cytological Techniques: Methods used to study CELLS.Capillaries: The minute vessels that connect the arterioles and venules.Protein Binding: The process in which substances, either endogenous or exogenous, bind to proteins, peptides, enzymes, protein precursors, or allied compounds. Specific protein-binding measures are often used as assays in diagnostic assessments.Cattle: Domesticated bovine animals of the genus Bos, usually kept on a farm or ranch and used for the production of meat or dairy products or for heavy labor.Rats, Sprague-Dawley: A strain of albino rat used widely for experimental purposes because of its calmness and ease of handling. It was developed by the Sprague-Dawley Animal Company.Movement: The act, process, or result of passing from one place or position to another. It differs from LOCOMOTION in that locomotion is restricted to the passing of the whole body from one place to another, while movement encompasses both locomotion but also a change of the position of the whole body or any of its parts. Movement may be used with reference to humans, vertebrate and invertebrate animals, and microorganisms. Differentiate also from MOTOR ACTIVITY, movement associated with behavior.Cell Adhesion: Adherence of cells to surfaces or to other cells.Fluorescent Antibody Technique, Indirect: A form of fluorescent antibody technique commonly used to detect serum antibodies and immune complexes in tissues and microorganisms in specimens from patients with infectious diseases. The technique involves formation of an antigen-antibody complex which is labeled with fluorescein-conjugated anti-immunoglobulin antibody. (From Bennington, Saunders Dictionary & Encyclopedia of Laboratory Medicine and Technology, 1984)Negative Staining: The technique of washing tissue specimens with a concentrated solution of a heavy metal salt and letting it dry. The specimen will be covered with a very thin layer of the metal salt, being excluded in areas where an adsorbed macromolecule is present. The macromolecules allow electrons from the beam of an electron microscope to pass much more readily than the heavy metal; thus, a reversed or negative image of the molecule is created.Organelles: Specific particles of membrane-bound organized living substances present in eukaryotic cells, such as the MITOCHONDRIA; the GOLGI APPARATUS; ENDOPLASMIC RETICULUM; LYSOSOMES; PLASTIDS; and VACUOLES.Rhodamines: A family of 3,6-di(substituted-amino)-9-benzoate derivatives of xanthene that are used as dyes and as indicators for various metals; also used as fluorescent tracers in histochemistry.Fluorescein-5-isothiocyanate: Fluorescent probe capable of being conjugated to tissue and proteins. It is used as a label in fluorescent antibody staining procedures as well as protein- and amino acid-binding techniques.Calcium: A basic element found in nearly all organized tissues. It is a member of the alkaline earth family of metals with the atomic symbol Ca, atomic number 20, and atomic weight 40. Calcium is the most abundant mineral in the body and combines with phosphorus to form calcium phosphate in the bones and teeth. It is essential for the normal functioning of nerves and muscles and plays a role in blood coagulation (as factor IV) and in many enzymatic processes.Epithelium: One or more layers of EPITHELIAL CELLS, supported by the basal lamina, which covers the inner or outer surfaces of the body.Cryoultramicrotomy: The technique of using a cryostat or freezing microtome, in which the temperature is regulated to -20 degrees Celsius, to cut ultrathin frozen sections for microscopic (usually, electron microscopic) examination.Optical Phenomena: LIGHT, it's processes and properties, and the characteristics of materials interacting with it.Photomicrography: Photography of objects viewed under a microscope using ordinary photographic methods.Instructional Films and VideosProtein Transport: The process of moving proteins from one cellular compartment (including extracellular) to another by various sorting and transport mechanisms such as gated transport, protein translocation, and vesicular transport.Cell Movement: The movement of cells from one location to another. Distinguish from CYTOKINESIS which is the process of dividing the CYTOPLASM of a cell.Recombinant Fusion Proteins: Recombinant proteins produced by the GENETIC TRANSLATION of fused genes formed by the combination of NUCLEIC ACID REGULATORY SEQUENCES of one or more genes with the protein coding sequences of one or more genes.Cornea: The transparent anterior portion of the fibrous coat of the eye consisting of five layers: stratified squamous CORNEAL EPITHELIUM; BOWMAN MEMBRANE; CORNEAL STROMA; DESCEMET MEMBRANE; and mesenchymal CORNEAL ENDOTHELIUM. It serves as the first refracting medium of the eye. It is structurally continuous with the SCLERA, avascular, receiving its nourishment by permeation through spaces between the lamellae, and is innervated by the ophthalmic division of the TRIGEMINAL NERVE via the ciliary nerves and those of the surrounding conjunctiva which together form plexuses. (Cline et al., Dictionary of Visual Science, 4th ed)Algorithms: A procedure consisting of a sequence of algebraic formulas and/or logical steps to calculate or determine a given task.Webcasts as Topic: Transmission of live or pre-recorded audio or video content via connection or download from the INTERNET.Computer-Assisted Instruction: A self-learning technique, usually online, involving interaction of the student with programmed instructional materials.Mice, Inbred C57BLEndocytosis: Cellular uptake of extracellular materials within membrane-limited vacuoles or microvesicles. ENDOSOMES play a central role in endocytosis.Fluorescence: The property of emitting radiation while being irradiated. The radiation emitted is usually of longer wavelength than that incident or absorbed, e.g., a substance can be irradiated with invisible radiation and emit visible light. X-ray fluorescence is used in diagnosis.Equipment Failure Analysis: The evaluation of incidents involving the loss of function of a device. These evaluations are used for a variety of purposes such as to determine the failure rates, the causes of failures, costs of failures, and the reliability and maintainability of devices.Actin Cytoskeleton: Fibers composed of MICROFILAMENT PROTEINS, which are predominately ACTIN. They are the smallest of the cytoskeletal filaments.Epithelial Cells: Cells that line the inner and outer surfaces of the body by forming cellular layers (EPITHELIUM) or masses. Epithelial cells lining the SKIN; the MOUTH; the NOSE; and the ANAL CANAL derive from ectoderm; those lining the RESPIRATORY SYSTEM and the DIGESTIVE SYSTEM derive from endoderm; others (CARDIOVASCULAR SYSTEM and LYMPHATIC SYSTEM) derive from mesoderm. Epithelial cells can be classified mainly by cell shape and function into squamous, glandular and transitional epithelial cells.Blotting, Western: Identification of proteins or peptides that have been electrophoretically separated by blot transferring from the electrophoresis gel to strips of nitrocellulose paper, followed by labeling with antibody probes.Nanoparticles: 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.Kinetics: The rate dynamics in chemical or physical systems.HeLa Cells: The first continuously cultured human malignant CELL LINE, derived from the cervical carcinoma of Henrietta Lacks. These cells are used for VIRUS CULTIVATION and antitumor drug screening assays.Cytoplasmic Granules: Condensed areas of cellular material that may be bounded by a membrane.Swine: Any of various animals that constitute the family Suidae and comprise stout-bodied, short-legged omnivorous mammals with thick skin, usually covered with coarse bristles, a rather long mobile snout, and small tail. Included are the genera Babyrousa, Phacochoerus (wart hogs), and Sus, the latter containing the domestic pig (see SUS SCROFA).Remote Consultation: Consultation via remote telecommunications, generally for the purpose of diagnosis or treatment of a patient at a site remote from the patient or primary physician.Disease Models, Animal: Naturally occurring or experimentally induced animal diseases with pathological processes sufficiently similar to those of human diseases. They are used as study models for human diseases.Models, Molecular: Models used experimentally or theoretically to study molecular shape, electronic properties, or interactions; includes analogous molecules, computer-generated graphics, and mechanical structures.Image Enhancement: Improvement of the quality of a picture by various techniques, including computer processing, digital filtering, echocardiographic techniques, light and ultrastructural MICROSCOPY, fluorescence spectrometry and microscopy, scintigraphy, and in vitro image processing at the molecular level.Freeze Etching: A replica technique in which cells are frozen to a very low temperature and cracked with a knife blade to expose the interior surfaces of the cells or cell membranes. The cracked cell surfaces are then freeze-dried to expose their constituents. The surfaces are now ready for shadowing to be viewed using an electron microscope. This method differs from freeze-fracturing in that no cryoprotectant is used and, thus, allows for the sublimation of water during the freeze-drying process to etch the surfaces.Capsule Endoscopy: Non-invasive, endoscopic imaging by use of VIDEO CAPSULE ENDOSCOPES to perform examination of the gastrointestinal tract, especially the small bowel.Telemedicine: Delivery of health services via remote telecommunications. This includes interactive consultative and diagnostic services.Nanostructures: Materials which have structured components with at least one dimension in the range of 1 to 100 nanometers. These include NANOCOMPOSITES; NANOPARTICLES; NANOTUBES; and NANOWIRES.Lenses: Pieces of glass or other transparent materials used for magnification or increased visual acuity.Histological Techniques: Methods of preparing tissue for examination and study of the origin, structure, function, or pathology.Educational Technology: Systematic identification, development, organization, or utilization of educational resources and the management of these processes. It is occasionally used also in a more limited sense to describe the use of equipment-oriented techniques or audiovisual aids in educational settings. (Thesaurus of ERIC Descriptors, December 1993, p132)Biological Transport: The movement of materials (including biochemical substances and drugs) through a biological system at the cellular level. The transport can be across cell membranes and epithelial layers. It also can occur within intracellular compartments and extracellular compartments.Flow Cytometry: Technique using an instrument system for making, processing, and displaying one or more measurements on individual cells obtained from a cell suspension. Cells are usually stained with one or more fluorescent dyes specific to cell components of interest, e.g., DNA, and fluorescence of each cell is measured as it rapidly transverses the excitation beam (laser or mercury arc lamp). Fluorescence provides a quantitative measure of various biochemical and biophysical properties of the cell, as well as a basis for cell sorting. Other measurable optical parameters include light absorption and light scattering, the latter being applicable to the measurement of cell size, shape, density, granularity, and stain uptake.Venules: The minute vessels that collect blood from the capillary plexuses and join together to form veins.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.Coloring Agents: Chemicals and substances that impart color including soluble dyes and insoluble pigments. They are used in INKS; PAINTS; and as INDICATORS AND REAGENTS.Electron Microscope Tomography: A tomographic technique for obtaining 3-dimensional images with transmission electron microscopy.Collagen: A polypeptide substance comprising about one third of the total protein in mammalian organisms. It is the main constituent of SKIN; CONNECTIVE TISSUE; and the organic substance of bones (BONE AND BONES) and teeth (TOOTH).Aluminum Silicates: Any of the numerous types of clay which contain varying proportions of Al2O3 and SiO2. They are made synthetically by heating aluminum fluoride at 1000-2000 degrees C with silica and water vapor. (From Hawley's Condensed Chemical Dictionary, 11th ed)Electron Probe Microanalysis: Identification and measurement of ELEMENTS and their location based on the fact that X-RAYS emitted by an element excited by an electron beam have a wavelength characteristic of that element and an intensity related to its concentration. It is performed with an electron microscope fitted with an x-ray spectrometer, in scanning or transmission mode.Rats, Wistar: A strain of albino rat developed at the Wistar Institute that has spread widely at other institutions. This has markedly diluted the original strain.Analog-Digital Conversion: The process of converting analog data such as continually measured voltage to discrete, digital form.Polymers: Compounds formed by the joining of smaller, usually repeating, units linked by covalent bonds. These compounds often form large macromolecules (e.g., BIOPOLYMERS; PLASTICS).Biophysics: The study of PHYSICAL PHENOMENA and PHYSICAL PROCESSES as applied to living things.Mutation: Any detectable and heritable change in the genetic material that causes a change in the GENOTYPE and which is transmitted to daughter cells and to succeeding generations.Bacterial Proteins: Proteins found in any species of bacterium.Tubulin: A microtubule subunit protein found in large quantities in mammalian brain. It has also been isolated from SPERM FLAGELLUM; CILIA; and other sources. Structurally, the protein is a dimer with a molecular weight of approximately 120,000 and a sedimentation coefficient of 5.8S. It binds to COLCHICINE; VINCRISTINE; and VINBLASTINE.Cricetinae: A subfamily in the family MURIDAE, comprising the hamsters. Four of the more common genera are Cricetus, CRICETULUS; MESOCRICETUS; and PHODOPUS.Corrosion Casting: A tissue preparation technique that involves the injecting of plastic (acrylates) into blood vessels or other hollow viscera and treating the tissue with a caustic substance. This results in a negative copy or a solid replica of the enclosed space of the tissue that is ready for viewing under a scanning electron microscope.Optical Processes: Behavior of LIGHT and its interactions with itself and materials.Dogs: The domestic dog, Canis familiaris, comprising about 400 breeds, of the carnivore family CANIDAE. They are worldwide in distribution and live in association with people. (Walker's Mammals of the World, 5th ed, p1065)Temperature: The property of objects that determines the direction of heat flow when they are placed in direct thermal contact. The temperature is the energy of microscopic motions (vibrational and translational) of the particles of atoms.Microscopy, Energy-Filtering Transmission Electron: An analytical transmission electron microscopy method using an electron microscope fitted with an energy filtering lens. The method is based on the principle that some of the ELECTRONS passing through the specimen will lose energy when they ionize inner shell electrons of the atoms in the specimen. The amount of energy loss is dependent upon the element. Analysis of the energy loss spectrum (ELECTRON ENERGY-LOSS SPECTROSCOPY) reveals the elemental composition of a specimen. It is used analytically and quantitatively to determine which, how much of, and where specific ELEMENTS are in a sample. For example, it is used for elemental mapping of PHOSPHORUS to trace the strands of NUCLEIC ACIDS in nucleoprotein complexes.Golgi Apparatus: A stack of flattened vesicles that functions in posttranslational processing and sorting of proteins, receiving them from the rough ENDOPLASMIC RETICULUM and directing them to secretory vesicles, LYSOSOMES, or the CELL MEMBRANE. The movement of proteins takes place by transfer vesicles that bud off from the rough endoplasmic reticulum or Golgi apparatus and fuse with the Golgi, lysosomes or cell membrane. (From Glick, Glossary of Biochemistry and Molecular Biology, 1990)Spectrum Analysis, Raman: Analysis of the intensity of Raman scattering of monochromatic light as a function of frequency of the scattered light.Fibroblasts: Connective tissue cells which secrete an extracellular matrix rich in collagen and other macromolecules.Imitative Behavior: The mimicking of the behavior of one individual by another.Fluoresceins: A family of spiro(isobenzofuran-1(3H),9'-(9H)xanthen)-3-one derivatives. These are used as dyes, as indicators for various metals, and as fluorescent labels in immunoassays.Molecular Imaging: The use of molecularly targeted imaging probes to localize and/or monitor biochemical and cellular processes via various imaging modalities that include RADIONUCLIDE IMAGING; ULTRASONOGRAPHY; MAGNETIC RESONANCE IMAGING; FLUORESCENCE IMAGING; and MICROSCOPY.Image Interpretation, Computer-Assisted: Methods developed to aid in the interpretation of ultrasound, radiographic images, etc., for diagnosis of disease.Laryngoscopes: Endoscopes for examining the interior of the larynx.Subcellular Fractions: Components of a cell produced by various separation techniques which, though they disrupt the delicate anatomy of a cell, preserve the structure and physiology of its functioning constituents for biochemical and ultrastructural analysis. (From Alberts et al., Molecular Biology of the Cell, 2d ed, p163)Teaching: The educational process of instructing.Protein Conformation: The characteristic 3-dimensional shape of a protein, including the secondary, supersecondary (motifs), tertiary (domains) and quaternary structure of the peptide chain. PROTEIN STRUCTURE, QUATERNARY describes the conformation assumed by multimeric proteins (aggregates of more than one polypeptide chain).Cellular Phone: Analog or digital communications device in which the user has a wireless connection from a telephone to a nearby transmitter. It is termed cellular because the service area is divided into multiple "cells." As the user moves from one cell area to another, the call is transferred to the local transmitter.Light: That portion of the electromagnetic spectrum in the visible, ultraviolet, and infrared range.Scattering, Radiation: The diversion of RADIATION (thermal, electromagnetic, or nuclear) from its original path as a result of interactions or collisions with atoms, molecules, or larger particles in the atmosphere or other media. (McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)Antibodies, Monoclonal: Antibodies produced by a single clone of cells.Escherichia coli: A species of gram-negative, facultatively anaerobic, rod-shaped bacteria (GRAM-NEGATIVE FACULTATIVELY ANAEROBIC RODS) commonly found in the lower part of the intestine of warm-blooded animals. It is usually nonpathogenic, but some strains are known to produce DIARRHEA and pyogenic infections. Pathogenic strains (virotypes) are classified by their specific pathogenic mechanisms such as toxins (ENTEROTOXIGENIC ESCHERICHIA COLI), etc.ComputersCell Size: The quantity of volume or surface area of CELLS.Photobleaching: Light-induced change in a chromophore, resulting in the loss of its absorption of light of a particular wave length. The photon energy causes a conformational change in the photoreceptor proteins affecting PHOTOTRANSDUCTION. This occurs naturally in the retina (ADAPTATION, OCULAR) on long exposure to bright light. Photobleaching presents problems when occurring in PHOTODYNAMIC THERAPY, and in FLUORESCENCE MICROSCOPY. On the other hand, this phenomenon is exploited in the technique, FLUORESCENCE RECOVERY AFTER PHOTOBLEACHING, allowing measurement of the movements of proteins and LIPIDS in the CELL MEMBRANE.Freezing: Liquids transforming into solids by the removal of heat.Neurons: The basic cellular units of nervous tissue. Each neuron consists of a body, an axon, and dendrites. Their purpose is to receive, conduct, and transmit impulses in the NERVOUS SYSTEM.Compact Disks: Computer disks storing data with a maximum reduction of space and bandwidth. The compact size reduces cost of transmission and storage.Parasitology: The study of parasites and PARASITIC DISEASES.Cell Survival: The span of viability of a cell characterized by the capacity to perform certain functions such as metabolism, growth, reproduction, some form of responsiveness, and adaptability.Virion: 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.Social Media: Platforms that provide the ability and tools to create and publish information accessed via the INTERNET. Generally these platforms have three characteristics with content user generated, high degree of interaction between creator and viewer, and easily integrated with other sites.Microspheres: Small uniformly-sized spherical particles, of micrometer dimensions, frequently labeled with radioisotopes or various reagents acting as tags or markers.Mitochondria: Semiautonomous, self-reproducing organelles that occur in the cytoplasm of all cells of most, but not all, eukaryotes. Each mitochondrion is surrounded by a double limiting membrane. The inner membrane is highly invaginated, and its projections are called cristae. Mitochondria are the sites of the reactions of oxidative phosphorylation, which result in the formation of ATP. They contain distinctive RIBOSOMES, transfer RNAs (RNA, TRANSFER); AMINO ACYL T RNA SYNTHETASES; and elongation and termination factors. Mitochondria depend upon genes within the nucleus of the cells in which they reside for many essential messenger RNAs (RNA, MESSENGER). Mitochondria are believed to have arisen from aerobic bacteria that established a symbiotic relationship with primitive protoeukaryotes. (King & Stansfield, A Dictionary of Genetics, 4th ed)Fluorescence Resonance Energy Transfer: A type of FLUORESCENCE SPECTROSCOPY using two FLUORESCENT DYES with overlapping emission and absorption spectra, which is used to indicate proximity of labeled molecules. This technique is useful for studying interactions of molecules and PROTEIN FOLDING.Protein Structure, Tertiary: The level of protein structure in which combinations of secondary protein structures (alpha helices, beta sheets, loop regions, and motifs) pack together to form folded shapes called domains. Disulfide bridges between cysteines in two different parts of the polypeptide chain along with other interactions between the chains play a role in the formation and stabilization of tertiary structure. Small proteins usually consist of only one domain but larger proteins may contain a number of domains connected by segments of polypeptide chain which lack regular secondary structure.Data Compression: Information application based on a variety of coding methods to minimize the amount of data to be stored, retrieved, or transmitted. Data compression can be applied to various forms of data, such as images and signals. It is used to reduce costs and increase efficiency in the maintenance of large volumes of data.Metal Nanoparticles: Nanoparticles produced from metals whose uses include biosensors, optics, and catalysts. In biomedical applications the particles frequently involve the noble metals, especially gold and silver.User-Computer Interface: The portion of an interactive computer program that issues messages to and receives commands from a user.Brain: The part of CENTRAL NERVOUS SYSTEM that is contained within the skull (CRANIUM). Arising from the NEURAL TUBE, the embryonic brain is comprised of three major parts including PROSENCEPHALON (the forebrain); MESENCEPHALON (the midbrain); and RHOMBENCEPHALON (the hindbrain). The developed brain consists of CEREBRUM; CEREBELLUM; and other structures in the BRAIN STEM.Transfection: The uptake of naked or purified DNA by CELLS, usually meaning the process as it occurs in eukaryotic cells. It is analogous to bacterial transformation (TRANSFORMATION, BACTERIAL) and both are routinely employed in GENE TRANSFER TECHNIQUES.Education, Distance: Education via communication media (correspondence, radio, television, computer networks) with little or no in-person face-to-face contact between students and teachers. (ERIC Thesaurus, 1997)Stress, Mechanical: A purely physical condition which exists within any material because of strain or deformation by external forces or by non-uniform thermal expansion; expressed quantitatively in units of force per unit area.X-Ray Diffraction: The scattering of x-rays by matter, especially crystals, with accompanying variation in intensity due to interference effects. Analysis of the crystal structure of materials is performed by passing x-rays through them and registering the diffraction image of the rays (CRYSTALLOGRAPHY, X-RAY). (From McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)Cell Count: The number of CELLS of a specific kind, usually measured per unit volume or area of sample.Carbocyanines: Compounds that contain three methine groups. They are frequently used as cationic dyes used for differential staining of biological materials.Biophysical Phenomena: The physical characteristics and processes of biological systems.Cell Line, Tumor: A cell line derived from cultured tumor cells.Microscopy, Electrochemical, Scanning: A scanning probe microscopy technique that uses an ultramicroelectrode as the scanning probe that simultaneously records changes in electrochemical potential as it scans thereby creating topographical images with localized electrochemical information.Biofilms: Encrustations, formed from microbes (bacteria, algae, fungi, plankton, or protozoa) embedding in extracellular polymers, that adhere to surfaces such as teeth (DENTAL DEPOSITS); PROSTHESES AND IMPLANTS; and catheters. Biofilms are prevented from forming by treating surfaces with DENTIFRICES; DISINFECTANTS; ANTI-INFECTIVE AGENTS; and antifouling agents.Kidney: Body organ that filters blood for the secretion of URINE and that regulates ion concentrations.Microcirculation: The circulation of the BLOOD through the MICROVASCULAR NETWORK.Liposomes: Artificial, single or multilaminar vesicles (made from lecithins or other lipids) that are used for the delivery of a variety of biological molecules or molecular complexes to cells, for example, drug delivery and gene transfer. They are also used to study membranes and membrane proteins.Cell Wall: The outermost layer of a cell in most PLANTS; BACTERIA; FUNGI; and ALGAE. The cell wall is usually a rigid structure that lies external to the CELL MEMBRANE, and provides a protective barrier against physical or chemical agents.Skin: The outer covering of the body that protects it from the environment. It is composed of the DERMIS and the EPIDERMIS.Elasticity: Resistance and recovery from distortion of shape.Apoptosis: One of the mechanisms by which CELL DEATH occurs (compare with NECROSIS and AUTOPHAGOCYTOSIS). Apoptosis is the mechanism responsible for the physiological deletion of cells and appears to be intrinsically programmed. It is characterized by distinctive morphologic changes in the nucleus and cytoplasm, chromatin cleavage at regularly spaced sites, and the endonucleolytic cleavage of genomic DNA; (DNA FRAGMENTATION); at internucleosomal sites. This mode of cell death serves as a balance to mitosis in regulating the size of animal tissues and in mediating pathologic processes associated with tumor growth.DNA: A deoxyribonucleotide polymer that is the primary genetic material of all cells. Eukaryotic and prokaryotic organisms normally contain DNA in a double-stranded state, yet several important biological processes transiently involve single-stranded regions. DNA, which consists of a polysugar-phosphate backbone possessing projections of purines (adenine and guanine) and pyrimidines (thymine and cytosine), forms a double helix that is held together by hydrogen bonds between these purines and pyrimidines (adenine to thymine and guanine to cytosine).Role Playing: The adopting or performing the role of another significant individual in order to gain insight into the behavior of that person.Organoids: An organization of cells into an organ-like structure. Organoids can be generated in culture. They are also found in certain neoplasms.Dancing: Rhythmic and patterned body movements which are usually performed to music.Diffusion: The tendency of a gas or solute to pass from a point of higher pressure or concentration to a point of lower pressure or concentration and to distribute itself throughout the available space. Diffusion, especially FACILITATED DIFFUSION, is a major mechanism of BIOLOGICAL TRANSPORT.Base Sequence: The sequence of PURINES and PYRIMIDINES in nucleic acids and polynucleotides. It is also called nucleotide sequence.Erythrocytes: Red blood cells. Mature erythrocytes are non-nucleated, biconcave disks containing HEMOGLOBIN whose function is to transport OXYGEN.Dextrans: A group of glucose polymers made by certain bacteria. Dextrans are used therapeutically as plasma volume expanders and anticoagulants. They are also commonly used in biological experimentation and in industry for a wide variety of purposes.Hydrogen-Ion Concentration: The normality of a solution with respect to HYDROGEN ions; H+. It is related to acidity measurements in most cases by pH = log 1/2[1/(H+)], where (H+) is the hydrogen ion concentration in gram equivalents per liter of solution. (McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)Photography: Method of making images on a sensitized surface by exposure to light or other radiant energy.Vacuoles: Any spaces or cavities within a cell. They may function in digestion, storage, secretion, or excretion.Glutaral: One of the protein CROSS-LINKING REAGENTS that is used as a disinfectant for sterilization of heat-sensitive equipment and as a laboratory reagent, especially as a fixative.