| 释义 |
nuclear magnetic resonance
nuclear magnetic resonancen. Abbr. NMR The absorption of electromagnetic radiation of a specific frequency by an atomic nucleus placed in a strong magnetic field, used especially to analyze tissues of the body in magnetic resonance imaging.nuclear magnetic resonance n (General Physics) a technique for determining the magnetic moments of nuclei by subjecting a substance to high-frequency radiation and a large magnetic field. The technique is used as a method of determining structure. Abbreviation: NMR See also electron spin resonance nu′clear magnet′ic res′onance
n. the selective absorption of electromagnetic radiation by an atomic nucleus in the presence of a strong, static, magnetic field. [1940–45] nuclear magnetic resonance The absorption of energy (as specific frequencies of radio waves) by the nuclei of atoms that are placed within a strong magnetic field. Because certain atoms absorb specific frequencies, nuclear magnetic resonance is used to analyze substances in spectroscopy and to examine soft body tissues in magnetic resonance imaging (MRI).Thesaurus| Noun | 1. | nuclear magnetic resonance - resonance of protons to radiation in a magnetic fieldNMR, proton magnetic resonancemagnetic resonance - resonance of electrons or atoms or molecules or nuclei to radiation frequencies as a result of space quantization in a magnetic field |
Translations
nuclear magnetic resonance
nuclear magnetic resonance: see magnetic resonancemagnetic resonance,
in physics and chemistry, phenomenon produced by simultaneously applying a steady magnetic field and electromagnetic radiation (usually radio waves) to a sample of atoms and then adjusting the frequency of the radiation and the strength of the magnetic field
..... Click the link for more information. .nuclear magnetic resonance[′nü·klē·ər mag′ned·ik ′rez·ən·əns] (physics) A phenomenon exhibited by a large number of atomic nuclei, in which nuclei in a static magnetic field absorb energy from a radio-frequency field at certain characteristic frequencies. Abbreviated NMR. Also known as magnetic nuclear resonance. nuclear magnetic resonance
nuclear [noo´kle-ar] pertaining to a nucleus.nuclear magnetic resonance a phenomenon exhibited by many atomic nuclei: when placed in a constant magnetic field, the nuclei absorb electromagnetic radiation at a few characteristic frequencies. By applying an external magnetic field to a solution in a constant radio frequency field, it is possible to determine the structure of an unknown compound. An application of this technique, called magnetic resonance imaging, permits imaging of soft tissues of the body by distinguishing between hydrogen atoms in different environments.nuclear medicine technologist a health care professional whose duties include positioning and attending to patients undergoing medicine" >nuclear medicine procedures, operating imaging devices (scintillation cameras and rectilinear scanners) under the direction of the nuclear medicine physician, preparing radiopharmaceuticals for administration to patients, making dose calculations for in vivo procedures, performing quality control procedures, and utilizing a knowledge of radiation physics and radiation safety to minimize the radiation exposure to patients, to the technologist and coworkers, and to the public. There are currently three organizations that certify nuclear medicine technologists: the American Registry of Radiologic Technologists (ARRT), the American Society of Clinical Pathologists (ASCP), and the Nuclear Medicine Technology Certification Board (NMTCB). Individuals certified by the ARRT are designated RT(N)(ARRT); those certified by the ASCP are designated NM(ASCP); and those certified by the NMTCB are designated CNMT.
resonance [rez´o-nans] 1. the prolongation and intensification of sound produced by transmission of its vibrations to a cavity, especially such a sound elicited by percussion. Decrease of resonance is called dullness; its increase, flatness.2. a vocal sound heard on auscultation.3. mesomerism.amphoric resonance a sound resembling that produced by blowing over the mouth of an empty bottle.nuclear magnetic resonance see nuclear magnetic resonance.skodaic resonance increased percussion resonance at the upper part of the chest, with flatness below it; heard over a large pleural effusion or area of consolidation.tympanic resonance tympanitic resonance (def. 2).tympanitic resonance 1. the peculiar sound elicited by percussing a tympanitic abdomen.2. the drumlike reverberation of a cavity full of air; called also tympanic resonance.vocal resonance (VR) the sound of ordinary speech as heard through the chest wall.nu·cle·ar mag·net·ic res·o·nance (NMR), the phenomenon in which certain atomic nuclei possessing a magnetic moment will precess around the axis of a strong external magnetic field, the frequency of precession (Larmor frequency) being specific for each nucleus and the strength of the magnetic field; spinning nuclei induce their own oscillating magnetic fields, and therefore emit electromagnetic radiation that can produce a detectable signal at the Larmor frequency. NMR is used as a method of determining structure and assessing molecular dynamics and is applied clinically in magnetic resonance imaging.nuclear magnetic resonancen. Abbr. NMR The absorption of electromagnetic radiation of a specific frequency by an atomic nucleus placed in a strong magnetic field, used especially to analyze tissues of the body in magnetic resonance imaging.nuclear magnetic resonance See Magnetic resonance imaging, NMR. Nuclear magnetic resonance Diagnostic NM • In vivo–eg injection of radiocontrast to detect an ↑/↓ in local 'signal'–uptake in suspected bone metastases • In vitro–assays of clinical specimens, eg radio immunoassay–RIA for various hormones, eg human chorionic gonadotropin–β-HCG, insulin, and TSH Therapeutic NM Radiation oncology Administration of a 'hot' isotope to sterilize a particular area, and prevent malignant cells from growing & dividing Note: RIAs are being replaced by ELISAs, which are easier to perform, the reagents are more easily stored, and do not have the problems inherent in using and disposing of radioactive waste; nuclear medicine also encompasses in vivo diagnostics in the form of scintillation counters to 'scan' various body regions for the presence of increased uptake of radionuclides, which when focal, implies primary neoplasia or metastases nu·cle·ar mag·net·ic res·o·nance (NMR) (nū'klē-ăr mag-net'ik rez'ŏ-năns) The phenomenon in which certain atomic nuclei possessing a magnetic moment will precess around the axis of a strong external magnetic field, the frequency of precession being specific for each nucleus and the strength of the magnetic field; spinning nuclei induce their own oscillating magnetic fields and therefore emit electromagnetic radiation that can produce a detectable signal. NMR is used as a method of identifying covalent bonds and is applied clinically in magnetic resonance imaging. nuclear magnetic resonance (NMR) See MAGNETIC RESONANCE IMAGING (MRI).nu·cle·ar mag·net·ic res·o·nance(NMR) (nū'klē-ăr mag-net'ik rez'ŏ-năns) The phenomenon in which certain atomic nuclei possessing a magnetic moment will precess around the axis of a strong external magnetic field, the frequency of precession being specific for each nucleus and the strength of the magnetic field; spinning nuclei induce their own oscillating magnetic fields and therefore emit electromagnetic radiation that can produce a detectable signal. NMR is used as a method of identifying covalent bonds and is applied clinically in magnetic resonance imagingAcronymsSeenaked mole ratnuclear magnetic resonance
Related to nuclear magnetic resonance: Nuclear magnetic resonance imagingSynonyms for nuclear magnetic resonancenoun resonance of protons to radiation in a magnetic fieldSynonyms- NMR
- proton magnetic resonance
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