Abstract:
:The magnetization subtraction technique (MS), which is equivalent to the inversion recovery technique in strong magnetic fields, has been implemented in dynamic nuclear polarization-enhanced magnetic resonance imaging (DNPI). The general theoretical basis of the MS method, which can be applied to DNPI or to prepolarized MRI in weak magnetic fields (such as Earth's magnetic field), is introduced. Details are provided about the signal amplitude, dynamic range of the method, and conditions required to observe signal void in samples with specific T1 relaxation times. The experimental results obtained with MS DNPI are presented and discussed. In the experiments, electron spin resonance irradiation frequencies of 199 MHz and 16.2 MHz were employed. Also, T1 contrast manipulation in the polarizing and in the detection magnetic field is discussed and demonstrated for MS DNPI.
journal_name
Magn Reson Medjournal_title
Magnetic resonance in medicineauthors
Planinsic G,Grucker D,Stepisnik Jdoi
10.1002/mrm.1910350316subject
Has Abstractpub_date
1996-03-01 00:00:00pages
379-83issue
3eissn
0740-3194issn
1522-2594journal_volume
35pub_type
杂志文章abstract::When using tracer kinetic modeling to analyze dynamic contrast-enhanced MRI (DCE-MRI) it is necessary to identify an appropriate arterial input function (AIF). The measured AIF is often poorly sampled in both clinical and preclinical MR systems due to the initial rapid increase in contrast agent concentration and the ...
journal_title:Magnetic resonance in medicine
pub_type: 杂志文章
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更新日期:2009-05-01 00:00:00
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pub_type: 杂志文章,随机对照试验
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更新日期:2015-03-01 00:00:00
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更新日期:2004-04-01 00:00:00
abstract::The absolute partial pressure of oxygen (pO(2)) in the mammary gland pad and femoral muscle of female mice was measured using EPR oximetry at 700 MHz. A small quantity of lithium phthalocyanine (LiPc) crystals was implanted in both mammary and femoral muscle tissue of female C3H mice. Subsequent EPR measurements were ...
journal_title:Magnetic resonance in medicine
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更新日期:2005-12-01 00:00:00
abstract:PURPOSE:To improve ultrahigh field diffusion-weighted imaging (DWI) in the presence of inhomogeneous transmit B1 field by designing a novel semi-adiabatic single-refocused DWI technique. METHODS:A 180° slice-selective, adiabatic radiofrequency (RF) pulse of 4 ms duration was designed using the adiabatic Shinnar-Le Rou...
journal_title:Magnetic resonance in medicine
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doi:10.1002/mrm.25790
更新日期:2016-05-01 00:00:00
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更新日期:1993-04-01 00:00:00
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journal_title:Magnetic resonance in medicine
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更新日期:2000-02-01 00:00:00
abstract::In this work a 3D fully balanced steady-state spin-echo sequence (bSSSE) was designed and implemented on a 3-Tesla whole-body MR scanner. In contrast to previously introduced nonbalanced SSSE (nbSSSE) sequences, bSSSE features fully rewound imaging gradients. Additionally, all phase encodings and the readout prephasin...
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更新日期:2006-11-01 00:00:00
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journal_title:Magnetic resonance in medicine
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doi:10.1002/mrm.10159
更新日期:2002-06-01 00:00:00
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更新日期:2001-06-01 00:00:00
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更新日期:1986-10-01 00:00:00
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更新日期:2007-11-01 00:00:00
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更新日期:1995-08-01 00:00:00
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journal_title:Magnetic resonance in medicine
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更新日期:1987-10-01 00:00:00
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journal_title:Magnetic resonance in medicine
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更新日期:2004-09-01 00:00:00
abstract:PURPOSE:All methods presented to date to map both conductivity and permittivity rely on multiple acquisitions to compute quantitatively the magnitude of radiofrequency transmit fields, B1+. In this work, we propose a method to compute both conductivity and permittivity based solely on relative receive coil sensitivitie...
journal_title:Magnetic resonance in medicine
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更新日期:2015-07-01 00:00:00
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更新日期:1997-11-01 00:00:00
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更新日期:2020-12-13 00:00:00
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更新日期:2003-10-01 00:00:00
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更新日期:2004-02-01 00:00:00