Abstract:
:The effect on lung ventilation of bronchoconstriction induced by serotonin (intravenous injection of 50 microg/kg of serotonin) was imaged using a hyperpolarized (3)He MR ventilation protocol in spontaneously breathing rats. Lung function maps assessing airflow obstruction, a key feature in clinical pneumology, were derived from dynamic image series acquired after inhalation of (3)He gas. Dynamic ventilation (3)He MR images spanning a respiratory cycle were obtained using a retrospective cine image reconstruction procedure. Two parameters, defined as signal amplitude and maximum signal decay rate, were derived from the time course of the MR signal for each pixel. These parameters were averaged over regions of interest placed in the lower part of the right and left lungs and submitted to statistical analysis. A homogeneous and significant decrease of signal amplitude and maximum signal decay rate after serotonin injection was observed for each rat on the parametric color maps. The data indicate that dynamic ventilation HP (3)He MRI can be used to assess, in a spatially resolved manner, the ventilation function of spontaneously breathing rats and the effects of agents eliciting short-lasting bronchoconstriction.
journal_name
Magn Reson Medjournal_title
Magnetic resonance in medicineauthors
Mosbah K,Stupar V,Berthezène Y,Beckmann N,Crémillieux Ydoi
10.1002/mrm.22391subject
Has Abstractpub_date
2010-06-01 00:00:00pages
1669-74issue
6eissn
0740-3194issn
1522-2594journal_volume
63pub_type
杂志文章abstract:PURPOSE:To propose a phase error correction scheme for monopolar time-interleaved multi-echo gradient echo water-fat imaging that allows accurate and robust complex-based quantification of the proton density fat fraction (PDFF). METHODS:A three-step phase correction scheme is proposed to address a) a phase term induce...
journal_title:Magnetic resonance in medicine
pub_type: 杂志文章
doi:10.1002/mrm.26485
更新日期:2017-09-01 00:00:00
abstract:PURPOSE:Evaluate the usefulness of single-shot and of interleaved spatiotemporally encoded (SPEN) methods to perform diffusion tensor imaging (DTI) under various preclinical and clinical settings. METHODS:A formalism for analyzing SPEN DTI data is presented, tailored to account for the spatially dependent b-matrix wei...
journal_title:Magnetic resonance in medicine
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doi:10.1002/mrm.26197
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abstract::Sinusoidal capillarization induces microcirculatory changes in liver cirrhosis and fibrosis. The purpose of this study was to assess whether contrast-enhanced MRI can be used to demonstrate the effects of sinusoidal capillarization in liver fibrosis. Dynamic MRI after injection of a low-molecular-weight contrast agent...
journal_title:Magnetic resonance in medicine
pub_type: 杂志文章
doi:10.1002/mrm.10420
更新日期:2003-04-01 00:00:00
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journal_title:Magnetic resonance in medicine
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更新日期:2016-04-01 00:00:00
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journal_title:Magnetic resonance in medicine
pub_type: 杂志文章
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更新日期:2013-12-01 00:00:00
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journal_title:Magnetic resonance in medicine
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journal_title:Magnetic resonance in medicine
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doi:10.1002/mrm.1910400214
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journal_title:Magnetic resonance in medicine
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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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journal_title:Magnetic resonance in medicine
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journal_title:Magnetic resonance in medicine
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doi:10.1002/mrm.20480
更新日期:2005-06-01 00:00:00
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journal_title:Magnetic resonance in medicine
pub_type: 杂志文章
doi:10.1002/mrm.22522
更新日期:2010-11-01 00:00:00
abstract::The chemical shift of water and fat resonances in proton MRI allows separation of water and fat signal from chemical shift encoded data. This work describes an automatic method that produces separate water and fat images as well as quantitative maps of fat signal fraction and T2* from complex multiecho gradient-recall...
journal_title:Magnetic resonance in medicine
pub_type: 杂志文章
doi:10.1002/mrm.23185
更新日期:2012-06-01 00:00:00
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journal_title:Magnetic resonance in medicine
pub_type: 杂志文章
doi:10.1002/mrm.1910390214
更新日期:1998-02-01 00:00:00
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journal_title:Magnetic resonance in medicine
pub_type: 杂志文章
doi:10.1002/mrm.1910270220
更新日期:1992-10-01 00:00:00
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journal_title:Magnetic resonance in medicine
pub_type: 杂志文章
doi:10.1002/(sici)1522-2594(199904)41:4<743::aid-mrm13
更新日期:1999-04-01 00:00:00
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journal_title:Magnetic resonance in medicine
pub_type: 杂志文章
doi:10.1002/mrm.25915
更新日期:2016-09-01 00:00:00
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journal_title:Magnetic resonance in medicine
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doi:10.1002/mrm.21676
更新日期:2008-09-01 00:00:00
abstract::Diffusion-weighted imaging (DWI) is frequently used to diagnose stroke. However, the origin of the observed reduction in the apparent diffusion coefficient (ADC) in the acute phase following ischemia is not well understood. Although cell swelling is considered to play an important role, it is unclear whether this can ...
journal_title:Magnetic resonance in medicine
pub_type: 杂志文章
doi:10.1002/mrm.20353
更新日期:2005-02-01 00:00:00
abstract::The hypothesis was tested that the intravoxel distribution of water diffusion rates, as measured with a stretched-exponential model of diffusion-weighted imaging (DWI), is a marker of brain tumor invasion. Eight rats underwent intracerebral inoculation of C6 glioma cells. In three rats, cells were labeled with a fluor...
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更新日期:2004-11-01 00:00:00
abstract::The differential effects of high temperature on 9L rat gliosarcoma cells cultured in two distinctive forms, namely, anchored monolayer cells and multicellular spheroids, were investigated using 31P nuclear magnetic resonance spectroscopy. The critical temperatures resulting in irreversible changes in cellular energeti...
journal_title:Magnetic resonance in medicine
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doi:10.1002/mrm.1910190233
更新日期:1991-06-01 00:00:00
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journal_title:Magnetic resonance in medicine
pub_type: 杂志文章
doi:10.1002/(sici)1522-2594(199903)41:3<479::aid-mrm9>
更新日期:1999-03-01 00:00:00
abstract:PURPOSE:To characterize the fundamental limits of MRI near metallic implants on RF excitation, frequency encoding, and chemical shift-encoding water-fat separation. METHODS:Multicomponent three-dimensional (3D) digital models of a total hip and a total knee replacement were used to construct material-specific suscepti...
journal_title:Magnetic resonance in medicine
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更新日期:2015-12-01 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
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更新日期:2019-02-01 00:00:00
abstract::To detect perfusion abnormalities in areas of high magnetic susceptibility in the brain, an arterial spin-labeling MRI technique utilizing flow-sensitive alternating inversion recovery (FAIR) and half-Fourier single shot turbo spin-echo (HASTE) for spin preparation and image acquisition, respectively, was developed. I...
journal_title:Magnetic resonance in medicine
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更新日期:2001-03-01 00:00:00
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journal_title:Magnetic resonance in medicine
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更新日期:2019-03-01 00:00:00
abstract::The estrogen receptor (ER) is a major prognostic biomarker of breast cancer, currently determined in surgical specimens by immunohistochemistry. Two new ER-targeted probes, pyridine-tetra-acetate-Gd chelate (PTA-Gd) conjugated either to 17β-estradiol (EPTA-Gd) or to tamoxifen (TPTA-Gd), were explored as contrast agent...
journal_title:Magnetic resonance in medicine
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更新日期:2013-07-01 00:00:00
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journal_title:Magnetic resonance in medicine
pub_type: 杂志文章
doi:10.1002/mrm.1910280214
更新日期:1992-12-01 00:00:00
abstract::Two different types of (co-registered) images of the same slice of tissue will generally have different spatial resolutions. The judicious pixel-by-pixel combination of their data can be accomplished to yield a single image exhibiting properties of both. Here, axial (18)FDG PET and (1)H(2)O MR images of the human brai...
journal_title:Magnetic resonance in medicine
pub_type: 杂志文章
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更新日期:1999-08-01 00:00:00
abstract::Chemical shifts were extracted from in vivo 3-dimensional 31P NMR CSI data and pH images were constructed. The images could spatially resolve tissue pH ranging from 5.8 to 7.2 (with uncertainty of 0.11-0.17 pH unit) in an ischemia-reperfusion model of diabetic rat calf muscles. ...
journal_title:Magnetic resonance in medicine
pub_type: 杂志文章
doi:10.1002/mrm.1910290214
更新日期:1993-02-01 00:00:00