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Desflurane
Desflurane (1,2,2,2-tetrafluoroethyl difluoromethyl ether) is a highly fluorinated methyl ethyl ether used for maintenance of general anesthesia. Like halothane, enflurane, and isoflurane, it is a racemic mixture of (''R'') and (''S'') optical isomers (enantiomers). Together with sevoflurane, it is gradually replacing isoflurane for human use, except in economically undeveloped areas, where its high cost precludes its use. It has the most rapid onset and offset of the volatile anesthetic drugs used for general anesthesia due to its low solubility in blood. Some drawbacks of desflurane are its low potency, its pungency and its high cost (though at low flow fresh gas rates, the cost difference between desflurane and isoflurane appears to be insignificant). It may cause tachycardia and airway irritability when administered at concentrations greater than 10% by volume. Due to this airway irritability, desflurane is infrequently used to induce anesthesia via inhalation techni ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Halogenated Ether
Halogenated ethers are a subcategory of ethers—organic chemicals that contain an oxygen atom connected to two alkyl groups or similar structures. An example of an ether is the solvent diethyl ether. Halogenated ethers differ from other ethers because there are one or more halogen atoms—fluorine, chlorine, bromine, or iodine—as substituents on the carbon groups. . Examples of commonly used halogenated ethers include isoflurane, Sevoflurane, sevofluorane and desflurane. History An ideal inhaled anesthetic wasn't found until 1950. Volatile substances like diethyl ether, which have severe risks of nausea, were used before. Diethyl ether has the unfortunate disadvantage of being extremely flammable, especially in the presence of enriched oxygen mixtures. James Young Simpson, an obstetrics surgeon, used ethers to help women relieve their labor pains but ultimately deemed them unsuitable due to their drawbacks. Simpson and his friends tested the halogenated hydrocarbon, chloro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Volatile Anesthetic
An inhalational anesthetic is a chemical compound possessing general anesthetic properties that is delivered via inhalation. They are administered through a face mask, laryngeal mask airway or tracheal tube connected to an anesthetic vaporiser and an anesthetic delivery system. Agents of significant contemporary clinical interest include volatile anesthetic agents such as isoflurane, sevoflurane and desflurane, as well as certain anesthetic gases such as nitrous oxide and xenon. List of inhalational anaesthetic agents Currently-used agents * Desflurane * Isoflurane * Nitrous oxide * Sevoflurane * Xenon Previously-used agents Although some of these are still used in clinical practice and in research, the following anaesthetic agents are primarily of historical interest in developed countries: * Acetylene * Chloroethane (ethyl chloride) * Chloroform * Cryofluorane * Cyclopropane * Diethyl ether * Divinyl ether * Enflurane * Ethylene * Fluroxene * Halothane (still widely use ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Anaesthetic Vaporiser
An anaesthetic machine (British English) or anesthesia machine (American English) is a medical device used to generate and mix a fresh gas flow of medical gases and inhalational anaesthetic agents for the purpose of inducing and maintaining anaesthesia. The machine is commonly used together with a mechanical ventilator, breathing circuit, breathing system, suction (medicine), suction equipment, and Medical monitor, patient monitoring devices; strictly speaking, the term "anaesthetic machine" refers only to the component which generates the gas flow, but modern machines usually integrate all these devices into one combined freestanding unit, which is colloquially referred to as the "anaesthetic machine" for the sake of simplicity. In the developed world, the most frequent type in use is the continuous-flow anaesthetic machine or "Boyle's machine", which is designed to provide an accurate supply of medical gases mixed with an accurate concentration of anaesthetic vapour, and to del ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Anaesthetic Machine
An anaesthetic machine (British English) or anesthesia machine (American English) is a medical device used to generate and mix a fresh gas flow of medical gases and inhalational anaesthetic agents for the purpose of inducing and maintaining anaesthesia. The machine is commonly used together with a mechanical ventilator, breathing system, suction equipment, and patient monitoring devices; strictly speaking, the term "anaesthetic machine" refers only to the component which generates the gas flow, but modern machines usually integrate all these devices into one combined freestanding unit, which is colloquially referred to as the "anaesthetic machine" for the sake of simplicity. In the developed world, the most frequent type in use is the continuous-flow anaesthetic machine or "Boyle's machine", which is designed to provide an accurate supply of medical gases mixed with an accurate concentration of anaesthetic vapour, and to deliver this continuously to the patient at a safe pre ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
GABAA Receptor
The GABAA receptor (GABAAR) is an ionotropic receptor and ligand-gated ion channel. Its endogenous Ligand (biochemistry), ligand is γ-aminobutyric acid (GABA), the major inhibitory neurotransmitter in the central nervous system. Accurate regulation of GABAergic transmission through appropriate developmental processes, specificity to neural cell types, and responsiveness to activity is crucial for the proper functioning of nearly all aspects of the central nervous system (CNS). Upon opening, the GABAA receptor on the Chemical synapse, postsynaptic cell is selectively permeable to Chloride, chloride ions () and, to a lesser extent, Bicarbonate, bicarbonate ions (). GABAAR are members of the ligand-gated ion channel receptor superfamily, which is a chloride channel family with a dozen or more heterotetrametric subtypes and 19 distinct subunits. These subtypes have distinct brain regional and subcellular localization, age-dependent expression, and the ability to undergo plastic alt ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Glycine Receptor
The glycine receptor (abbreviated as GlyR or GLR) is the receptor Receptor may refer to: * Sensory receptor, in physiology, any neurite structure that, on receiving environmental stimuli, produces an informative nerve impulse *Receptor (biochemistry), in biochemistry, a protein molecule that receives and respond ... of the amino acid neurotransmitter glycine. GlyR is an ionotropic receptor that produces its effects through inhibitory postsynaptic potential, chloride currents. It is one of the most widely distributed inhibitory receptors in the central nervous system and has important roles in a variety of physiological processes, especially in mediating inhibitory neurotransmission in the spinal cord and brainstem. The receptor can be activated by a range of simple amino acids including glycine, Beta-alanine, β-alanine and taurine, and can be selectively blocked by the high-affinity competitive antagonist strychnine. Caffeine is a competitive antagonist of GlyR. Cannabinoids en ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Anesthesiology (journal)
''Anesthesiology'', a monthly peer-reviewed medical journal founded in 1940, leads the world in publication of peer-reviewed novel research that transforms clinical practice and fundamental understanding in anesthesiology: the practice of perioperative, critical care, and pain medicine. ''Anesthesiology'' is the official journal of the American Society of Anesthesiologists, but operates with complete editorial autonomy. The broad dissemination of the research published in the journal includes an active social media program and additional tools designed to engage readers with the content. ''Anesthesiology'' is committed to publishing and disseminating the highest quality work to inform daily clinical practice and transform the practice of medicine in our specialty. The editor-in-chief is James P. Rathmell, and it is published by Lippincott Williams & Wilkins on behalf of the American Society of Anesthesiologists. According to the ''Journal Citation Reports'', the journal has a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Negative Allosteric Modulator
In pharmacology and biochemistry, allosteric modulators are a group of substances that bind to a receptor to change that receptor's response to stimuli. Some of them, like benzodiazepines or alcohol, function as psychoactive drugs. The site that an allosteric modulator binds to (i.e., an ''allosteric site'') is not the same one to which an endogenous agonist of the receptor would bind (i.e., an ''orthosteric site''). Modulators and agonists can both be called receptor ligands. Allosteric modulators can be 1 of 3 types either: positive, negative or neutral. Positive types increase the response of the receptor by increasing the probability that an agonist will bind to a receptor (i.e. affinity), increasing its ability to activate the receptor (i.e. efficacy), or both. Negative types decrease the agonist affinity and/or efficacy. Neutral types don't affect agonist activity but can stop other modulators from binding to an allosteric site. Some modulators also work as allosteric agonist ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Diário Oficial Da União
The ''Diário Oficial da União'' (literally ''Official Diary of the Union''), abbreviated DOU, is the government gazette, official gazette of the Federal Government of Brazil, Federal Government of Brazil. It is published since 1 October 1862 and was created via the Imperial Decree 1,177 of its 9 September as the ''Official Journal of the Empire of Brazil''. Its current name was adopted after Brazil became a federal republic, and the "Union" came into being as the legal personality of the new federal government. The official journal is published by the Imprensa Nacional, Brazilian National Press. Though the journal has been published since 1862, it had many predecessors, as follows: # Gazeta do Rio de Janeiro (10/9/1808 – 29.12.1821) # Gazeta do Rio (1/1/1822 – 31/12/1822) # Diário do Governo (2/1/1823 – 28/6/1833) # Diário Fluminense (21/5/1824 – 24/4/1831) # Correio Oficial (1/7/1833 – 30/6/1836) e (2/1/1830 – 30/12/1840) # Without proper journal (31/12/1840 – ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Positive Allosteric Modulator
In pharmacology and biochemistry, allosteric modulators are a group of substances that bind to a receptor to change that receptor's response to stimuli. Some of them, like benzodiazepines or alcohol, function as psychoactive drugs. The site that an allosteric modulator binds to (i.e., an ''allosteric site'') is not the same one to which an endogenous agonist of the receptor would bind (i.e., an ''orthosteric site''). Modulators and agonists can both be called receptor ligands. Allosteric modulators can be 1 of 3 types either: positive, negative or neutral. Positive types increase the response of the receptor by increasing the probability that an agonist will bind to a receptor (i.e. affinity), increasing its ability to activate the receptor (i.e. efficacy), or both. Negative types decrease the agonist affinity and/or efficacy. Neutral types don't affect agonist activity but can stop other modulators from binding to an allosteric site. Some modulators also work as allosteric agonis ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ligand-gated Ion Channel
Ligand-gated ion channels (LICs, LGIC), also commonly referred to as ionotropic receptors, are a group of transmembrane ion-channel proteins which open to allow ions such as sodium, Na+, potassium, K+, calcium, Ca2+, and/or chloride, Cl− to pass through the membrane in response to the binding of a chemical messenger (i.e. a ligand (biochemistry), ligand), such as a neurotransmitter. When a presynaptic neuron is excited, it releases a neurotransmitter from vesicles into the synaptic cleft. The neurotransmitter then binds to receptors located on the postsynaptic neuron. If these receptors are ligand-gated ion channels, a resulting conformational change opens the ion channels, which leads to a flow of ions across the cell membrane. This, in turn, results in either a depolarization, for an excitatory receptor response, or a hyperpolarization (biology), hyperpolarization, for an inhibitory response. These receptor proteins are typically composed of at least two different domains ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Racemic Mixture
In chemistry, a racemic mixture or racemate () is a mixture that has equal amounts (50:50) of left- and right-handed enantiomers of a chiral molecule or salt. Racemic mixtures are rare in nature, but many compounds are produced industrially as racemates. History The first known racemic mixture was racemic acid, which Louis Pasteur found to be a mixture of the two enantiomeric isomers of tartaric acid. He manually separated the crystals of a mixture, starting from an aqueous solution of the sodium ammonium salt of racemate tartaric acid. Pasteur benefited from the fact that ammonium tartrate salt gives enantiomeric crystals with distinct crystal forms (at 77 °F). Reasoning from the macroscopic scale down to the molecular, he reckoned that the molecules had to have non-superimposable mirror images. A sample with only a single enantiomer is an ''enantiomerically pure'' or ''enantiopure'' compound. Etymology The word ''racemic'' derives from Latin , meaning pertaining to a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
