Abstract：
:We propose a deuterium diffusion tracer approach to measure diffusion coefficient in the case of very short NMR relaxation times, too short for NMR pulsed field gradient sequences (T1 or T2 below 1 ms). We also treat the case of porous media containing metallic fibers (such as reinforced concrete) strongly disturbing the magnetic field, and the case of inhomogeneous porous media containing large non porous granulates. For the latter, we propose a hollow geometry maximizing the investigated volume and minimizing the experimental time. The method is a 3D diffusion technique in which samples are immersed in deuterium and the water content inside the sample is monitored as a function of time. Water diffusing outside the sample with very long relaxation times can be subtracted either from T2 relaxation time distribution or not polarizing these components using a short repeat delay. Using analytical formulations describing the concentration of a tracer diffusing out of a cylinder or a hollow cylinder, we can calculate the corresponding pore diffusion coefficient.
journal_name
Magn Reson Imagingjournal_title
Magnetic resonance imagingauthors
Fleury M,Berthe G,Chevalier Tdoi
10.1016/j.mri.2018.09.010subject
Has Abstractpub_date
2019-02-01 00:00:00pages
32-36eissn
0730-725Xissn
1873-5894pii
S0730-725X(18)30328-Xjournal_volume
56pub_type
杂志文章abstract：:Several recent articles have assessed the relative efficiency of nuclear magnetic resonance (NMR) pulse sequences. One consideration that has received little attention is the effect on image contrast of displaying images without information on the sign of the reconstructed signals. The radiofrequency receivers current...
journal_title：Magnetic resonance imaging
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journal_title：Magnetic resonance imaging
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journal_title：Magnetic resonance imaging
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doi：10.1016/0730-725x(94)91238-r
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journal_title：Magnetic resonance imaging
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pub_type： 杂志文章
doi：10.1016/0730-725x(86)91046-5
更新日期：1986-01-01 00:00:00
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journal_title：Magnetic resonance imaging
pub_type： 杂志文章
doi：10.1016/j.mri.2012.07.004
更新日期：2013-02-01 00:00:00
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journal_title：Magnetic resonance imaging
pub_type： 杂志文章
doi：10.1016/j.mri.2007.05.002
更新日期：2007-07-01 00:00:00
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doi：10.1016/j.mri.2014.08.028
更新日期：2015-01-01 00:00:00
abstract：:Acetaminophen (APAP) toxicity is responsible for approximately half of all cases of acute liver failure in the United States. The mouse model of APAP toxicity is widely used to examine mechanisms of APAP toxicity. Noninvasive approaches would allow for serial measurements in a single animal to study the effects of exp...
journal_title：Magnetic resonance imaging
pub_type： 杂志文章
doi：10.1016/j.mri.2011.09.023
更新日期：2012-02-01 00:00:00
abstract：:We retrospectively compared the diagnostic accuracy of abdominal ultrasound (US), computed tomography (CT), and magnetic resonance imaging (MRI) studies performed on the same individual to determine the relative performance of these modalities in the evaluation of disease processes, arising from different intra-abdomi...
journal_title：Magnetic resonance imaging
pub_type： 杂志文章
doi：10.1016/j.mri.2003.01.001
更新日期：2004-01-01 00:00:00
abstract：:The objective of this study was to describe magnetic resonance (MR) findings with a 1.5T imager for hepatic parenchymal changes after proton beam radiotherapy. Thirty-two patients who received proton radiotherapy with doses of 50-87 Gy underwent MR imaging 1-75 months (mean 22 months) after the start of irradiation. A...
journal_title：Magnetic resonance imaging
pub_type： 杂志文章
doi：10.1016/s0730-725x(00)00152-1
更新日期：2000-07-01 00:00:00
abstract：OBJECTIVE:The purpose of this study was to analyze flow patterns in the pulmonary circulation of healthy volunteers by using 4D flow magnetic resonance imaging. MATERIALS AND METHODS:The study was approved by the local ethics committee and all subjects gave written informed consent. Eighteen volunteers underwent a 4D ...
journal_title：Magnetic resonance imaging
pub_type： 杂志文章
doi：10.1016/j.mri.2012.06.036
更新日期：2013-02-01 00:00:00
abstract：:Left ventricle (LV) segmentation plays an important role in the diagnosis of cardiovascular diseases. The cardiac contractile function can be quantified by measuring the segmentation results of LVs. Fully convolutional networks (FCNs) have been proven to be able to segment images. However, a large number of annotated ...
journal_title：Magnetic resonance imaging
pub_type： 杂志文章
doi：10.1016/j.mri.2019.08.004
更新日期：2020-02-01 00:00:00
abstract：OBJECTIVE:3D Time-of-flight (TOF) magnetic resonance angiography is commonly used for vascular analyses. A quantification of longitudinal morphological changes usually requires the registration of TOF image sequences acquired at different time points. The aim of this study was to evaluate the precision of different 3D ...
journal_title：Magnetic resonance imaging
pub_type： 杂志文章
doi：10.1016/j.mri.2014.08.011
更新日期：2014-12-01 00:00:00
abstract：:Spatial normalization plays a key role in voxel-based analyses of brain images. We propose a highly accurate algorithm for high-dimensional spatial normalization of brain images based on the technique of symmetric optical flow. We first construct a three dimension optical model with the consistency assumption of inten...
journal_title：Magnetic resonance imaging
pub_type： 杂志文章
doi：10.1016/j.mri.2015.01.013
更新日期：2015-05-01 00:00:00
abstract：:A single-sided mobile NMR apparatus with a small Halbach magnet was constructed for the first time. It is lightweight, compact and exhibits good sensitivity. The weight of the device is only 2 kg, and the NMR signal of the pencil eraser block can be detected in one shot using the device. This study describes the chara...
journal_title：Magnetic resonance imaging
pub_type： 杂志文章
doi：10.1016/j.mri.2006.04.005
更新日期：2006-10-01 00:00:00
abstract：:Surface magnetic relaxation in porous media is usually attributed to hindered rotation or to paramagnetic impurities on the surface. In cement pastes, however, it seems reasonable to attribute surface relaxation to dipole interactions in water adsorbed as water of hydration on grain surfaces. The rate limiting factor ...
journal_title：Magnetic resonance imaging
pub_type： 杂志文章
doi：10.1016/0730-725x(94)91517-2
更新日期：1994-01-01 00:00:00
abstract：:Fricke-agarose gels have been irradiated with a proton beam. Then samples have been extracted at different depths with respect to the beam penetration distance, corresponding to different irradiation doses. Relaxation times T1 and T2, measured at 17 MHz, appear sensitive to this kind of radiation. In particular, T2 ex...
journal_title：Magnetic resonance imaging
pub_type： 杂志文章
doi：10.1016/s0730-725x(96)00380-3
更新日期：1997-01-01 00:00:00
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journal_title：Magnetic resonance imaging
pub_type： 杂志文章
doi：10.1016/j.mri.2012.06.037
更新日期：2013-02-01 00:00:00
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journal_title：Magnetic resonance imaging
pub_type： 杂志文章
doi：10.1016/j.mri.2017.01.008
更新日期：2017-06-01 00:00:00
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journal_title：Magnetic resonance imaging
pub_type： 杂志文章
doi：10.1016/j.mri.2015.06.010
更新日期：2015-11-01 00:00:00
abstract：:The fast Fourier flow technique offers a convenient way for extremely exact flow measurements. In combination with ECG gating, arterial flow can be studied. The total acquisition time for a single measurement is about 10 s, an ECG-gated cine sequence can be acquired in about 4 min. Fast Fourier flow can, therefore, be...
journal_title：Magnetic resonance imaging
pub_type： 杂志文章
doi：10.1016/0730-725x(88)90473-0
更新日期：1988-07-01 00:00:00
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journal_title：Magnetic resonance imaging
pub_type： 杂志文章
doi：10.1016/j.mri.2017.07.026
更新日期：2017-11-01 00:00:00
abstract：:The mapping of the human brain white matter fiber networks relative to deep subcortical and cortical gray matter requires high spatial resolution which is challenged by the low signal-to-noise ratio. The purpose of this short report was to introduce a whole brain high spatial resolution diffusion tensor imaging (DTI) ...
journal_title：Magnetic resonance imaging
pub_type： 杂志文章
doi：10.1016/j.mri.2008.10.007
更新日期：2009-06-01 00:00:00
abstract：:Measurements of time-dependent diffusion are performed on a rock sample saturated first with water, then methane and finally ethane. The gases were selected because their increased diffusivities and relaxation times allow probing greater length scales than water and because of their practical relevance. The nuclear ma...
journal_title：Magnetic resonance imaging
pub_type： 杂志文章
doi：10.1016/j.mri.2005.01.002
更新日期：2005-02-01 00:00:00
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journal_title：Magnetic resonance imaging
pub_type： 杂志文章
doi：10.1016/s0730-725x(99)00121-6
更新日期：2000-02-01 00:00:00
abstract：:1H Magnetic resonance imaging and 31P magnetic resonance spectroscopy (MRS) have been carried out in experimental rodent filariasis, i.e., Acanthocheilonema viteae infection in the rodent host, Mastomys coucha. The T2-weighted image of the infected host shows fine hyperintense thread like structures of adult filariid ...
journal_title：Magnetic resonance imaging
pub_type： 杂志文章
doi：10.1016/s0730-725x(97)00180-x
更新日期：1997-01-01 00:00:00
