Abstract:
:It is demonstrated that a high-resolution (1)H NMR spectrum of excised rat liver can be obtained using the technique of magic angle turning (MAT) at a sample spinning rate of 1 Hz. A variant of the phase-corrected MAT (PHORMAT) pulse sequence that includes a water suppression segment was developed for the investigation. The spectral resolution achieved with PHORMAT approaches that obtained from a standard magic angle spinning (MAS) experiment at a spinning rate of several kHz. With such ultra-slow spinning, tissue and cell damage associated with the standard MAS experiment is minimized or eliminated. The technique is potentially useful for obtaining high-resolution (1)H spectra in live animals.
journal_name
Magn Reson Medjournal_title
Magnetic resonance in medicineauthors
Hu JZ,Rommereim DN,Wind RAdoi
10.1002/mrm.10139subject
Has Abstractpub_date
2002-05-01 00:00:00pages
829-36issue
5eissn
0740-3194issn
1522-2594journal_volume
47pub_type
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journal_title:Magnetic resonance in medicine
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更新日期:2021-01-01 00:00:00
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journal_title:Magnetic resonance in medicine
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更新日期:2009-04-01 00:00:00
abstract::We constructed a device to compress small samples of articular cartilage while the samples were imaged in a 1.5 T imager. With the use of a piezoelectric piston, the device compressed 1-cm-diameter cylindrical samples of articular cartilage (200 microm) at a rate of 2 Hz. Simultaneously, we imaged the samples with a d...
journal_title:Magnetic resonance in medicine
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更新日期:2005-05-01 00:00:00
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journal_title:Magnetic resonance in medicine
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更新日期:2018-04-01 00:00:00
abstract::Functional MRI studies to date have been generally performed using the blood oxygenation level dependent (BOLD) contrast mechanism. Recently, it has been proposed that dynamic change in the apparent diffusion coefficient (ADC), measured using intravoxel incoherent motion (IVIM) weighting, can be used as a robust funct...
journal_title:Magnetic resonance in medicine
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abstract::The study of lung perfusion in normal and diseased subjects is of great interest to physiologists and physicians. In this work we demonstrate the application of a liquid-phase hyperpolarized (HP) carbon-13 ((13)C) tracer to magnetic resonance imaging (MRI) of the pulmonary vasculature and pulmonary perfusion in a porc...
journal_title:Magnetic resonance in medicine
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更新日期:2007-03-01 00:00:00
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journal_title:Magnetic resonance in medicine
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更新日期:2012-06-01 00:00:00
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pub_type: 杂志文章
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更新日期:2008-02-01 00:00:00
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journal_title:Magnetic resonance in medicine
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更新日期:2004-06-01 00:00:00
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journal_title:Magnetic resonance in medicine
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更新日期:2010-08-01 00:00:00
abstract::Time-dependent changes of T1 in the rotating frame (T1rho), diffusion, T2, and magnetization transfer contrast on cardiac arrest-induced global ischemia in rat were investigated. T1rho, as acquired with spin lock amplitudes >0.6 G, started to increase 10-20 sec after cardiac arrest followed by an increase within 3-4 m...
journal_title:Magnetic resonance in medicine
pub_type: 杂志文章
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更新日期:2001-09-01 00:00:00
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journal_title:Magnetic resonance in medicine
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更新日期:2017-05-01 00:00:00
abstract:PURPOSE:Simultaneous brain and spinal cord functional MRI is emerging as a new tool to study the central nervous system but is challenging. Poor B0 homogeneity and small size of the spinal cord are principal obstacles to this nascent technology. Here we extend a dynamic shimming approach, first posed by Finsterbusch, b...
journal_title:Magnetic resonance in medicine
pub_type: 杂志文章
doi:10.1002/mrm.27388
更新日期:2019-02-01 00:00:00
abstract:PURPOSE:Proof-of-concept study of mapping renal blood flow vector field according to the inverse solution to a mass transport model of time resolved tracer-labeled MRI data. THEORY AND METHODS:To determine tissue perfusion according to the underlying physics of spatiotemporal tracer concentration variation, the mass t...
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doi:10.1002/mrm.28584
更新日期:2021-04-01 00:00:00
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journal_title:Magnetic resonance in medicine
pub_type: 杂志文章
doi:10.1002/mrm.22124
更新日期:2009-11-01 00:00:00
abstract::Aim of the study was to determine distribution and depletion patterns of intramyocellular lipids (IMCL) in leg muscles before and after two types of standardized endurance exercise. ¹H-magnetic resonance spectroscopic imaging was performed (1) in the thigh of eight-trained cyclists after exercising on an ergometer for...
journal_title:Magnetic resonance in medicine
pub_type: 临床试验,杂志文章
doi:10.1002/mrm.24168
更新日期:2012-11-01 00:00:00
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journal_title:Magnetic resonance in medicine
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doi:10.1002/mrm.25196
更新日期:2014-05-01 00:00:00
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journal_title:Magnetic resonance in medicine
pub_type: 杂志文章
doi:10.1002/mrm.24443
更新日期:2013-07-01 00:00:00
abstract::The application of T1 rho an an alternative contrast parameter in high-field magnetic resonance histology (MRH) has been investigated. Spectroscopic measurements of T1 rho were performed on 5.75% agar and 1.0 mM MnCI2 phantoms at 9.4 T to validate the accuracy of the imaging measurements. Image studies were performed ...
journal_title:Magnetic resonance in medicine
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更新日期:1996-05-01 00:00:00
abstract::Flow-sensitive dephasing (FSD) magnetization preparation has been developed for black-blood vessel wall MRI and noncontrast MR angiography. The first-order gradient moment, m(1) , is a measure of the flow-sensitization imparted by an FSD preparative module. Determination of the optimal m(1) for each individual is high...
journal_title:Magnetic resonance in medicine
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更新日期:2011-04-01 00:00:00
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journal_title:Magnetic resonance in medicine
pub_type: 杂志文章
doi:10.1002/mrm.24807
更新日期:2014-04-01 00:00:00
abstract::A new strategy for a quantitative measurement of regional pulmonary ventilation using hyperpolarized helium-3 (3He) MRI has been developed. The method employs the build-up of the signal intensity after a variable number of (3)He breaths. A mathematical model of the signal dynamics is presented, from which the local ve...
journal_title:Magnetic resonance in medicine
pub_type: 杂志文章
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更新日期:2002-08-01 00:00:00
abstract::Using NMR spectroscopy, we studied purified, human T lymphocytes in a serum-free medium. Purified cells were entrapped inside agarose beads and induced to proliferate by the mitogens phorbol-12-myristate-13-acetate and ionomycin. T lymphocytes in standard culture and inside agarose beads exhibit comparable viability, ...
journal_title:Magnetic resonance in medicine
pub_type: 杂志文章
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更新日期:1993-03-01 00:00:00
abstract::One-dimensional spectroscopic imaging of (13)C-4-glutamate turnover is performed in the human brain with a 6 cc nominal voxel resolution at 4T. Data were acquired with an indirect detection approach using a short spin echo single quantum (1)H-(13)C heteronuclear editing method and a 7 cm surface coil with quadrature (...
journal_title:Magnetic resonance in medicine
pub_type: 杂志文章
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更新日期:2000-11-01 00:00:00
abstract:PURPOSE:To develop a three-dimensional, free-breathing, late gadolinium enhancement (3D FB-LGE) cardiovascular magnetic resonance (CMR) technique, and to compare it with clinically used two-dimensional breath-hold LGE (2D BH-LGE). METHODS:The proposed 3D FB-LGE method consisted of inversion preparation, inversion dela...
journal_title:Magnetic resonance in medicine
pub_type: 杂志文章
doi:10.1002/mrm.26234
更新日期:2017-04-01 00:00:00
abstract::The purpose of this study was to determine the value of a blood-pool contrast media (NC100150, Nycomed Imaging (now Amersham Health) Oslo, Norway) for evaluation of venous thrombosis of the deep veins of the pelvis and lower extremities. Twelve patients were prospectively evaluated with conventional X-ray venography (...
journal_title:Magnetic resonance in medicine
pub_type: 临床试验,杂志文章,随机对照试验
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更新日期:2003-11-01 00:00:00
abstract:PURPOSE:The linear change of the water proton resonance frequency shift (PRFS) with temperature is used to monitor temperature change based on the temporal difference of image phase. Here, the effect of motion-induced susceptibility artifacts on the phase difference was studied in the context of mild radio frequency hy...
journal_title:Magnetic resonance in medicine
pub_type: 杂志文章
doi:10.1002/mrm.28302
更新日期:2020-11-01 00:00:00
abstract:PURPOSE:To measure the T1 and T2 relaxation times of water, metabolites, and macromolecules in the rat brain in vivo at 17.2T and achieve absolute quantification of the neurochemical profile. Relaxation times were compared with values from the literature found at lower magnetic fields. METHODS:(1) H NMR spectra were m...
journal_title:Magnetic resonance in medicine
pub_type: 杂志文章
doi:10.1002/mrm.25602
更新日期:2016-02-01 00:00:00