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Free Fraction
The free fraction is a parameter in pharmacokinetics and receptor-ligand kinetics. One speaks of two different free fractions: * ''Plasma free fraction'', previously referred to as ƒ1, is now referred to as ƒP according to consensus nomenclature. * ''Tissue free fraction'' (ƒND), previously referred to as ƒ2 The ''plasma free fraction'' is the fraction of the ligand at equilibrium in blood plasma that is not bound to plasma proteins. See also * Binding potential In pharmacokinetics and receptor-ligand kinetics the binding potential (BP) is a combined measure of the density of "available" neuroreceptors and the affinity of a drug to that neuroreceptor. Description Consider a ligand receptor binding syst ... References Others * Pharmacokinetics {{biochemistry-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pharmacokinetics
Pharmacokinetics (from Ancient Greek ''pharmakon'' "drug" and ''kinetikos'' "moving, putting in motion"; see chemical kinetics), sometimes abbreviated as PK, is a branch of pharmacology dedicated to determining the fate of substances administered to a living organism. The substances of interest include any chemical xenobiotic such as: pharmaceutical drugs, pesticides, food additives, cosmetics, etc. It attempts to analyze chemical metabolism and to discover the fate of a chemical from the moment that it is administered up to the point at which it is completely eliminated from the body. Pharmacokinetics is the study of how an organism affects a drug, whereas pharmacodynamics (PD) is the study of how the drug affects the organism. Both together influence dosing, benefit, and adverse effects, as seen in PK/PD models. Overview Pharmacokinetics describes how the body affects a specific xenobiotic/chemical after administration through the mechanisms of absorption and distribution, as ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nomenclature
Nomenclature (, ) is a system of names or terms, or the rules for forming these terms in a particular field of arts or sciences. The principles of naming vary from the relatively informal naming conventions, conventions of everyday speech to the internationally agreed principles, rules and recommendations that govern the formation and use of the specialist terms used in scientific and any other disciplines. Naming "things" is a part of general human communication using words and language: it is an aspect of everyday Taxonomy (general), taxonomy as people distinguish the objects of their experience, together with their similarities and differences, which observers Identification (information), identify, name and wikt:classification, classify. The use of names, as the many different kinds of nouns embedded in different languages, connects nomenclature to theoretical linguistics, while the way humans mentally structure the world in relation to semantics, word meanings and Experience ( ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
J Cereb Blood Flow Metab
The ''Journal of Cerebral Blood Flow & Metabolism'' is a monthly peer-reviewed medical journal the official journal of the International Society for Cerebral Blood Flow & Metabolism and publishes peer-reviewed research and review papers. covering research on experimental, theoretical, and clinical aspects of brain circulation, metabolism and imaging. The editor-in-chief is Jun Chen (University of Pittsburgh). According to the ''Journal Citation Reports'', the journal has a 2020 impact factor The impact factor (IF) or journal impact factor (JIF) of an academic journal is a scientometric index calculated by Clarivate that reflects the yearly mean number of citations of articles published in the last two years in a given journal, as i ... of 6.200. References External links * International Society for Cerebral Blood Flow & Metabolism Neuroscience journals Publications established in 1981 Nature Research academic journals English-language journals Monthly journals Delayed ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ligand
In coordination chemistry, a ligand is an ion or molecule (functional group) that binds to a central metal atom to form a coordination complex. The bonding with the metal generally involves formal donation of one or more of the ligand's electron pairs, often through Lewis bases. The nature of metal–ligand bonding can range from covalent to ionic. Furthermore, the metal–ligand bond order can range from one to three. Ligands are viewed as Lewis bases, although rare cases are known to involve Lewis acidic "ligands". Metals and metalloids are bound to ligands in almost all circumstances, although gaseous "naked" metal ions can be generated in a high vacuum. Ligands in a complex dictate the reactivity of the central atom, including ligand substitution rates, the reactivity of the ligands themselves, and redox. Ligand selection requires critical consideration in many practical areas, including bioinorganic and medicinal chemistry, homogeneous catalysis, and environmental chemi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Blood Plasma
Blood plasma is a light amber-colored liquid component of blood in which blood cells are absent, but contains proteins and other constituents of whole blood in suspension. It makes up about 55% of the body's total blood volume. It is the intravascular part of extracellular fluid (all body fluid outside cells). It is mostly water (up to 95% by volume), and contains important dissolved proteins (6–8%; e.g., serum albumins, globulins, and fibrinogen), glucose, clotting factors, electrolytes (, , , , , etc.), hormones, carbon dioxide (plasma being the main medium for excretory product transportation), and oxygen. It plays a vital role in an intravascular osmotic effect that keeps electrolyte concentration balanced and protects the body from infection and other blood-related disorders. Blood plasma is separated from the blood by spinning a vessel of fresh blood containing an anticoagulant in a centrifuge until the blood cells fall to the bottom of the tube. The blood plasma is t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Plasma Protein
Blood-proteins, also termed plasma proteins, are proteins present in blood plasma. They serve many different functions, including transport of lipids, hormones, vitamins and minerals in activity and functioning of the immune system. Other blood proteins act as enzymes, complement components, protease inhibitors or kinin precursors. Contrary to popular belief, haemoglobin is not a blood protein, as it is carried within red blood cells, rather than in the blood serum. Serum albumin accounts for 55% of blood proteins, is a major contributor to maintaining the oncotic pressure of plasma and assists, as a carrier, in the transport of lipids and steroid hormones. Globulins make up 38% of blood proteins and transport ions, hormones, and lipids assisting in immune function. Fibrinogen comprises 7% of blood proteins; conversion of fibrinogen to insoluble fibrin is essential for blood clotting. The remainder of the plasma proteins (1%) are regulatory proteins, such as enzymes, proenzymes ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Binding Potential
In pharmacokinetics and receptor-ligand kinetics the binding potential (BP) is a combined measure of the density of "available" neuroreceptors and the affinity of a drug to that neuroreceptor. Description Consider a ligand receptor binding system. Ligand with a concentration ''L'' associates with a receptor of concentration or availability ''R'' to form a ligand-receptor complex with concentration ''RL''. The binding potential is then the ratio ligand-receptor complex to free ligand at equilibrium and in the limit of L tending to 0, and is given symbol BP: BP=\frac\bigg, _ This quantity, originally defined by Mintun, describes the capacity of a receptor to bind ligand. It is a limit (L << Ki) of the general receptor association equation: and is thus also equivalent to: These equations apply equally when measuring the total receptor density or the residual receptor density available after binding to second ligand - availability. [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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