Biological Specimen Banks: Facilities that collect, store, and distribute tissues, e.g., cell lines, microorganisms, blood, sperm, milk, breast tissue, for use by others. Other uses may include transplantation and comparison of diseased tissues in the identification of cancer.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.Forensic Toxicology: The application of TOXICOLOGY knowledge to questions of law.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.Electron Microscope Tomography: A tomographic technique for obtaining 3-dimensional images with transmission electron microscopy.Specimen Handling: Procedures for collecting, preserving, and transporting of specimens sufficiently stable to provide accurate and precise results suitable for clinical interpretation.Spectroscopy, Electron Energy-Loss: A technique for analysis of the chemical composition of molecules. A substance is bombarded with monochromatic ELECTRONS. Some of the electrons passing through the specimen will lose energy when they ionize inner shell electrons of the atoms in the specimen. The energy loss is element dependent. Analysis of the energy loss spectrum reveals the elemental composition of a specimen. ENERGY-FILTERED TRANSMISSION ELECTRON MICROSCOPY is a type of electron energy loss spectroscopy carried out in electron microscopes specially outfitted to analyze the spectrum of electron energy loss.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.Gas Chromatography-Mass Spectrometry: A microanalytical technique combining mass spectrometry and gas chromatography for the qualitative as well as quantitative determinations of compounds.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.Tissue Banks: Centers for acquiring, characterizing, and storing organs or tissue for future use.Substance Abuse Detection: Detection of drugs that have been abused, overused, or misused, including legal and illegal drugs. Urine screening is the usual method of detection.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.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.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.Chromatography, Gas: Fractionation of a vaporized sample as a consequence of partition between a mobile gaseous phase and a stationary phase held in a column. Two types are gas-solid chromatography, where the fixed phase is a solid, and gas-liquid, in which the stationary phase is a nonvolatile liquid supported on an inert solid matrix.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)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.Electrons: Stable elementary particles having the smallest known negative charge, present in all elements; also called negatrons. Positively charged electrons are called positrons. The numbers, energies and arrangement of electrons around atomic nuclei determine the chemical identities of elements. Beams of electrons are called CATHODE RAYS.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.Reference Standards: A basis of value established for the measure of quantity, weight, extent or quality, e.g. weight standards, standard solutions, methods, techniques, and procedures used in diagnosis and therapy.Fatal Outcome: Death resulting from the presence of a disease in an individual, as shown by a single case report or a limited number of patients. This should be differentiated from DEATH, the physiological cessation of life and from MORTALITY, an epidemiological or statistical concept.Equipment Design: Methods of creating machines and devices.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.Eye Banks: Centers for storing various parts of the eye for future use.Chromatography, High Pressure Liquid: Liquid chromatographic techniques which feature high inlet pressures, high sensitivity, and high speed.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.Blood Banks: Centers for collecting, characterizing and storing human blood.Algorithms: A procedure consisting of a sequence of algebraic formulas and/or logical steps to calculate or determine a given task.Metabolomics: The systematic identification and quantitation of all the metabolic products of a cell, tissue, organ, or organism under varying conditions. The METABOLOME of a cell or organism is a dynamic collection of metabolites which represent its net response to current conditions.Metabolome: The dynamic collection of metabolites which represent a cell's or organism's net metabolic response to current conditions.Blood Specimen Collection: The taking of a blood sample to determine its character as a whole, to identify levels of its component cells, chemicals, gases, or other constituents, to perform pathological examination, etc.Quality Control: A system for verifying and maintaining a desired level of quality in a product or process by careful planning, use of proper equipment, continued inspection, and corrective action as required. (Random House Unabridged Dictionary, 2d ed)Marine Biology: The study of the origin, structure, development, growth, function, genetics, and reproduction of organisms which inhabit the OCEANS AND SEAS.Xanthine: A purine base found in most body tissues and fluids, certain plants, and some urinary calculi. It is an intermediate in the degradation of adenosine monophosphate to uric acid, being formed by oxidation of hypoxanthine. The methylated xanthine compounds caffeine, theobromine, and theophylline and their derivatives are used in medicine for their bronchodilator effects. (Dorland, 28th ed)Pentosyltransferases: Enzymes of the transferase class that catalyze the transfer of a pentose group from one compound to another.Periodicals as Topic: A publication issued at stated, more or less regular, intervals.Leishmania donovani: A parasitic hemoflagellate of the subgenus Leishmania leishmania that infects man and animals and causes visceral leishmaniasis (LEISHMANIASIS, VISCERAL). The sandfly genera Phlebotomus and Lutzomyia are the vectors.Bibliometrics: The use of statistical methods in the analysis of a body of literature to reveal the historical development of subject fields and patterns of authorship, publication, and use. Formerly called statistical bibliography. (from The ALA Glossary of Library and Information Science, 1983)Newspapers: Publications printed and distributed daily, weekly, or at some other regular and usually short interval, containing news, articles of opinion (as editorials and letters), features, advertising, and announcements of current interest. (Webster's 3d ed)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)Patents as Topic: Exclusive legal rights or privileges applied to inventions, plants, etc.Time Factors: Elements of limited time intervals, contributing to particular results or situations.International Cooperation: The interaction of persons or groups of persons representing various nations in the pursuit of a common goal or interest.National Institute of Diabetes and Digestive and Kidney Diseases (U.S.): Component of the NATIONAL INSTITUTES OF HEALTH. It conducts and supports basic and applied research for a national program in diabetes, endocrinology, and metabolic diseases; digestive diseases and nutrition; and kidney, urologic, and hematologic diseases. It was established in 1948.Research: Critical and exhaustive investigation or experimentation, having for its aim the discovery of new facts and their correct interpretation, the revision of accepted conclusions, theories, or laws in the light of newly discovered facts, or the practical application of such new or revised conclusions, theories, or laws. (Webster, 3d ed)Software: Sequential operating programs and data which instruct the functioning of a digital computer.BooksGenomics: The systematic study of the complete DNA sequences (GENOME) of organisms.Public Health: Branch of medicine concerned with the prevention and control of disease and disability, and the promotion of physical and mental health of the population on the international, national, state, or municipal level.Genetics, Medical: A subdiscipline of human genetics which entails the reliable prediction of certain human disorders as a function of the lineage and/or genetic makeup of an individual or of any two parents or potential parents.Health Policy: Decisions, usually developed by government policymakers, for determining present and future objectives pertaining to the health care system.Public Health Practice: The activities and endeavors of the public health services in a community on any level.