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Immunologic Tests
An immunoassay (IA) is a biochemical test that measures the presence or concentration of a macromolecule or a small molecule in a solution through the use of an antibody (usually) or an antigen (sometimes). The molecule detected by the immunoassay is often referred to as an "analyte" and is in many cases a protein, although it may be other kinds of molecules, of different sizes and types, as long as the proper antibodies that have the required properties for the assay are developed. Analytes in biological liquids such as blood plasma, serum or urine are frequently measured using immunoassays for medical and research purposes. Immunoassays come in many different formats and variations. Immunoassays may be run in multiple steps with reagents being added and washed away or separated at different points in the assay. Multi-step assays are often called separation immunoassays or heterogeneous immunoassays. Some immunoassays can be carried out simply by mixing the reagents and samples an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Biochemical
Biochemistry, or biological chemistry, is the study of chemical processes within and relating to living organisms. A sub-discipline of both chemistry and biology, biochemistry may be divided into three fields: structural biology, enzymology, and metabolism. Over the last decades of the 20th century, biochemistry has become successful at explaining living processes through these three disciplines. Almost all areas of the life sciences are being uncovered and developed through biochemical methodology and research. Voet (2005), p. 3. Biochemistry focuses on understanding the chemical basis that allows biological molecules to give rise to the processes that occur within living cells and between cells, Karp (2009), p. 2. in turn relating greatly to the understanding of tissues and organs as well as organism structure and function. Miller (2012). p. 62. Biochemistry is closely related to molecular biology, the study of the molecular mechanisms of biological phenomena. Astbu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chemiluminescence
Chemiluminescence (also chemoluminescence) is the emission of light (luminescence) as the result of a chemical reaction, i.e. a chemical reaction results in a flash or glow of light. A standard example of chemiluminescence in the laboratory setting is the luminol test. Here, blood is indicated by luminescence upon contact with iron in hemoglobin. When chemiluminescence takes place in living organisms, the phenomenon is called bioluminescence. A light stick emits light by chemiluminescence. Physical description As in many chemical reactions, chemiluminescence starts with the combining of two compounds, say A and B, to give a product C. Unlike most chemical reactions, the product C converts to a further product, which is produced in an electronically excited state often indicated with an asterisk: : A + B → C : C → D* D* then emits a photon (''h''ν), to give the ground state of D: I : D* → D + ''h''ν In theory, one photon of light should be given off for each mol ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fluorescence
Fluorescence is one of two kinds of photoluminescence, the emission of light by a substance that has absorbed light or other electromagnetic radiation. When exposed to ultraviolet radiation, many substances will glow (fluoresce) with colored visible light. The color of the light emitted depends on the chemical composition of the substance. Fluorescent materials generally cease to glow nearly immediately when the radiation source stops. This distinguishes them from the other type of light emission, phosphorescence. Phosphorescent materials continue to emit light for some time after the radiation stops. This difference in duration is a result of quantum spin effects. Fluorescence occurs when a photon from incoming radiation is absorbed by a molecule, exciting it to a higher energy level, followed by the emission of light as the molecule returns to a lower energy state. The emitted light may have a longer wavelength and, therefore, a lower photon energy than the absorbed radi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Applied And Environmental Microbiology
''Applied and Environmental Microbiology'' is a biweekly peer-reviewed scientific journal published by the American Society for Microbiology. It was established in 1953 as ''Applied Microbiology'' and obtained its current name in 1975. Articles older than six months are available free of cost from the website, however, the newly published articles within six months are available to subscribers only. According to the ''Journal Citation Reports'', the journal has a 2023 impact factor of 3.9. The journal has been ranked as one of the top 100 journals over the past 100 years in the fields of biology and medicine. Special Libraries Association100 Journals in last 100 years/ref> The editor-in-chief is Gemma Reguera (Michigan State University Michigan State University (Michigan State or MSU) is a public university, public Land-grant university, land-grant research university in East Lansing, Michigan, United States. It was founded in 1855 as the Agricultural College of the State o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Real-time Polymerase Chain Reaction
A real-time polymerase chain reaction (real-time PCR, or qPCR when used quantitatively) is a laboratory technique of molecular biology based on the polymerase chain reaction (PCR). It monitors the amplification of a targeted DNA molecule during the PCR (i.e., in real time), not at its end, as in conventional PCR. Real-time PCR can be used quantitatively and semi-quantitatively (i.e., above/below a certain amount of DNA molecules). Two common methods for the detection of PCR products in real-time PCR are (1) non-specific fluorescent dyes that Intercalation (biochemistry), intercalate with any double-stranded DNA and (2) sequence-specific DNA probes consisting of oligonucleotides that are labelled with a fluorescence, fluorescent reporter, which permits detection only after nucleic acid hybridisation, hybridization of the probe with its complementary sequence. The Minimum Information for Publication of Quantitative Real-Time PCR Experiments (MIQE) guidelines propose that the abb ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
American Medical News
''American Medical News'' was an American newspaper that covered business, policy, public health and legal issues affecting physician practices. ''American Medical News'' offered 24 print issues each year, and 52 online editions, with fresh news added each weekday. First published by the American Medical Association The American Medical Association (AMA) is an American professional association and lobbying group of physicians and medical students. This medical association was founded in 1847 and is headquartered in Chicago, Illinois. Membership was 271,660 ... as ''The AMA News'' in 1958, it was renamed in 1969 to reflect its broadened coverage. Most copies were distributed free as an AMA benefit of membership and to some non-member physicians, with internal medicine and family practice accounting for the majority of readers. The paper was intended to serve as an impartial and credible forum for information affecting physicians and their practices. The newspaper was shut down ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Radioimmunoassay
A radioimmunoassay (RIA) is an immunoassay that uses radioactive tracer, radiolabeled molecules in a stepwise formation of immune complexes. A RIA is a very sensitive in vitro assay technique used to measure concentrations of substances, usually measuring antigen concentrations (for example, hormone levels in blood) by use of antibody, antibodies. The RIA technique is extremely sensitivity (tests), sensitive and extremely Specificity (tests), specific, and although it requires specialized equipment, it remains among the least expensive methods to perform such measurements. It requires special precautions and licensing, since radioactive substances are used. In contrast, an immunoradiometric assay (IRMA) is an immunoassay that uses radiolabeled molecules but in an immediate rather than stepwise way. A radioallergosorbent test (RAST) is an example of radioimmunoassay. It is used to detect the causative allergen for an allergy. Method Classically, to perform a radioimmunoassay, a k ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Isotope
Isotopes are distinct nuclear species (or ''nuclides'') of the same chemical element. They have the same atomic number (number of protons in their Atomic nucleus, nuclei) and position in the periodic table (and hence belong to the same chemical element), but different nucleon numbers (mass numbers) due to different numbers of neutrons in their nuclei. While all isotopes of a given element have similar chemical properties, they have different atomic masses and physical properties. The term isotope is derived from the Greek roots isos (wikt:ἴσος, ἴσος "equal") and topos (wikt:τόπος, τόπος "place"), meaning "the same place"; thus, the meaning behind the name is that different isotopes of a single element occupy the same position on the periodic table. It was coined by Scottish doctor and writer Margaret Todd (doctor), Margaret Todd in a 1913 suggestion to the British chemist Frederick Soddy, who popularized the term. The number of protons within the atomic nuc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Glucose Oxidase
The glucose oxidase enzyme (GOx or GOD) also known as notatin (EC number 1.1.3.4) is an oxidoreductase that catalyses the oxidation of glucose to hydrogen peroxide and D-glucono-δ-lactone. This enzyme is produced by certain species of fungi and insects and displays antibacterial activity when oxygen and glucose are present. Glucose oxidase is widely used for the determination of free glucose in body fluids (medical testing), in vegetal raw material, and in the food industry. It also has many applications in biotechnologies, typically enzyme assays for biochemistry including biosensors in nanotechnologies. It was first isolated by Detlev Müller in 1928 from ''Aspergillus niger''. Function Several species of fungi and insects synthesize glucose oxidase, which produces hydrogen peroxide, which kills bacteria. Notatin, extracted from antibacterial cultures of '' Penicillium notatum'', was originally named Penicillin A, but was renamed to avoid confusion with penicillin. Not ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Alkaline Phosphatase
The enzyme alkaline phosphatase (ALP, alkaline phenyl phosphatase, also abbreviated PhoA) is a phosphatase with the physiological role of dephosphorylating compounds. The enzyme is found across a multitude of organisms, prokaryotes and eukaryotes alike, with the same general function, but in different structural forms suitable to the environment they function in. Alkaline phosphatase is found in the periplasmic space of '' E. coli'' bacteria. This enzyme is heat stable and has its maximum activity at high pH. In humans, it is found in many forms depending on its origin within the body – it plays an integral role in metabolism within the liver and development within the skeleton. Due to its widespread prevalence in these areas, its concentration in the bloodstream is used by diagnosticians as a biomarker in helping determine diagnoses such as hepatitis or osteomalacia. The level of alkaline phosphatase in the blood is checked through the ALP test, which is often par ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Horseradish Peroxidase
The enzyme horseradish peroxidase (HRP), found in the roots of horseradish, is used extensively in biochemistry applications. It is a metalloenzyme with many isoforms, of which the most studied type is C. It catalyzes the oxidation of various organic substrates by hydrogen peroxide. Structure The structure of the enzyme was first solved by X-ray crystallography in 1997; and has since been solved several times with various substrates. It is a large alpha-helix, alpha-helical glycoprotein which binds heme as a redox Cofactor (biochemistry), cofactor. Substrates Alone, the HRP enzyme, or conjugates thereof, is of little value; its presence must be made visible using a Substrate (biochemistry), substrate that, when Redox, oxidized by HRP using hydrogen peroxide as the oxidizing agent, yields a characteristic color change that is detectable by spectrophotometric methods. Numerous substrates for horseradish peroxidase have been described and commercialized to exploit the desir ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
ELISA Plate Image
The enzyme-linked immunosorbent assay (ELISA) (, ) is a commonly used analytical biochemistry assay, first described by Eva Engvall and Peter Perlmann in 1971. The assay is a solid-phase type of enzyme immunoassay (EIA) to detect the presence of a ligand (commonly an amino acid) in a liquid sample using antibodies directed against the ligand to be measured. ELISA has been used as a diagnostic tool in medicine, plant pathology, and biotechnology, as well as a quality control check in various industries. In the most simple form of an ELISA, antigens from the sample to be tested are attached to a surface. Then, a matching antibody is applied over the surface so it can bind the antigen. This antibody is linked to an enzyme, and then any unbound antibodies are removed. In the final step, a substance containing the enzyme's substrate is added. If there was binding, the subsequent reaction produces a detectable signal, most commonly a color change. Performing an ELISA involves at lea ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
