Abstract:
:The penetration of horse liver alcohol dehydrogenase (HLAD) molecules into polyacrylamide gel beads, which are used to immobilize the enzyme, was studied. HLAD was labeled with gadolinium diethylene-triamine-pentaacetic acid (Gd-DTPA), using the N-hydroxy-succinimide active ester of DTPA as a chelating agent. The HLAD-(Gd-DTPA)27 has a 3.7-fold larger longitudinal (R1) and a 14-fold larger transversal relaxivity (R2) (at 2.4 T) than the plain Gd-DTPA. A series of dry polyacrylamide gel beads, with total monomer concentration ranging from 5% to 30% were synthesized and swollen in a buffered solution of HLAD-(Gd-DTPA)27. The gel beads were examined with high resolution NMR imaging. The T1- and T2-weighted images revealed that the permeability for the labeled HLAD decreased with increasing total monomer concentration of the gel beads. These imaging results correlate fairly well with the enzymatic reactivities measured for the same range of gel beads but swollen in a solution of non labeled HLAD and NAD+ (nicotinamide adenine dinucleotide). It is concluded that Gd-labeling can be used to monitor the distribution of weakly concentrated, water soluble products in a solid matrix.
journal_name
Magn Reson Imagingjournal_title
Magnetic resonance imagingauthors
Spanoghe M,Lanens D,Gorrebeeck C,Dommisse R,Lemière G,Van der Linden A,Van de Vyver Fdoi
10.1016/0730-725x(91)90046-osubject
Has Abstractpub_date
1991-01-01 00:00:00pages
583-7issue
4eissn
0730-725Xissn
1873-5894pii
0730-725X(91)90046-Ojournal_volume
9pub_type
杂志文章abstract::Transverse relaxation rates for Carr-Purcell-Meiboom-Gill (CPMG) sequences increase with inter-echo time in presence of microscopic magnetic field inhomogeneities due to nuclear spin diffusion. For a weak field approximation that includes diffusion effects, the CPMG relaxation rate shift for proton diffusion around ca...
journal_title:Magnetic resonance imaging
pub_type: 杂志文章
doi:10.1016/j.mri.2016.03.016
更新日期:2016-09-01 00:00:00
abstract::Perfusion magnetic resonance imaging (MRI) is a promising non-invasive technique providing insights regarding the brain's microvascular architecture in vivo. The scalar perfusion metrics can be used for quantitative diagnostics of various brain abnormalities, in particular, in the stroke cases and tumours. However, co...
journal_title:Magnetic resonance imaging
pub_type: 杂志文章
doi:10.1016/j.mri.2018.11.007
更新日期:2019-04-01 00:00:00
abstract:PURPOSE:To evaluate the application of high-resolution MRI methodology for characterizing the fluid velocity field and evaluate fluid shear field within a simplified in vitro model of a bone-implant interface. MATERIALS AND METHODS:The study used a specific micromotion canine bone implant that has been used for over a...
journal_title:Magnetic resonance imaging
pub_type: 杂志文章
doi:10.1016/j.mri.2005.11.001
更新日期:2006-06-01 00:00:00
abstract::Magic-angle sample spinning is one of the cornerstones in high-resolution NMR of solid and semisolid materials. The technique enhances spectral resolution by averaging away rank 2 anisotropic spin interactions, thereby producing isotropic-like spectra with resolved chemical shifts and scalar couplings. In principle, i...
journal_title:Magnetic resonance imaging
pub_type: 杂志文章
doi:10.1016/j.mri.2004.11.067
更新日期:2005-02-01 00:00:00
abstract:PURPOSE:To evaluate the clinical outcomes of conservative management by observation with MRI of patients with branch-duct intraductal papillary mucinous neoplasms (BD-IPMNs). MATERIALS AND METHODS:Twenty-three consecutive patients, who were followed up by MRI with magnetic resonance cholangiopancreatography (MRCP) ove...
journal_title:Magnetic resonance imaging
pub_type: 杂志文章
doi:10.1016/j.mri.2010.06.026
更新日期:2010-12-01 00:00:00
abstract::Magnetic field inhomogeneities like eddy current-related gradient fields cause geometric distortions in echo-planar imaging (EPI). This in particular affects diffusion-weighted imaging where these distortions vary with the direction of the diffusion weighting and hamper the accurate determination of diffusion paramete...
journal_title:Magnetic resonance imaging
pub_type: 杂志文章
doi:10.1016/j.mri.2009.12.004
更新日期:2010-04-01 00:00:00
abstract::The amplitudes of gradient-echoes produced using static field gradients are sensitive to diffusion of tissue water during the echo evolution time. Gradient-echoes have been used to produce MR images in which image intensity is proportional to the self-diffusion coefficient of water. However, such measurements are subj...
journal_title:Magnetic resonance imaging
pub_type: 杂志文章
doi:10.1016/0730-725x(95)00051-h
更新日期:1995-01-01 00:00:00
abstract::Collagen fibers in tendons and entheses are highly ordered. The protons within the bound water are subject to dipolar interactions whose strength depends on the orientation of the fibers to the static magnetic field B(0). Clinical pulse sequences have been employed to investigate this magic angle effect of the Achille...
journal_title:Magnetic resonance imaging
pub_type: 杂志文章
doi:10.1016/j.mri.2008.09.003
更新日期:2009-05-01 00:00:00
abstract::Stimulated spin-echo and Carr-Purcell pulse sequences, with pulsed magnetic field gradients, have been used to study the self-diffusion processes of the water in swollen and in supercoiled polyacrylamide gels and in polysaccharides agarose gels, for different polymer concentrations. Restricted diffusion effects are ev...
journal_title:Magnetic resonance imaging
pub_type: 杂志文章
doi:10.1016/s0730-725x(96)00202-0
更新日期:1996-01-01 00:00:00
abstract::The purpose of this investigation is to evaluate the positioning and to confirm the volume concept of the Lea's Shield diaphragm utilizing MR imaging. We evaluated the device in two women, one nulliparous and one multiparous. We were able to comprehensively evaluate the device in both patients and answer all questions...
journal_title:Magnetic resonance imaging
pub_type: 杂志文章
doi:10.1016/s0730-725x(01)00385-x
更新日期:2001-06-01 00:00:00
abstract::Cross-terms between imaging and diffusion gradients, unaccounted for during tensor calculations, can lead to erroneous estimation of diffusivity and fractional anisotropy (FA) in regions of isotropic and anisotropic diffusion. Cross-term of magnitude 136.8±1.6 s/mm(2), artificially introduced in the slice-encode direc...
journal_title:Magnetic resonance imaging
pub_type: 杂志文章
doi:10.1016/j.mri.2012.02.021
更新日期:2012-07-01 00:00:00
abstract::A new phantom and evaluation method for experimental evaluation of 1H-magnetic resonance spectroscopy single volume localization techniques regarding signal contamination (C), defined as the part of the signal originating outside the volume of interest, is presented. The quality assessment method is based on a spheric...
journal_title:Magnetic resonance imaging
pub_type: 杂志文章
doi:10.1016/s0730-725x(99)00076-4
更新日期:1999-12-01 00:00:00
abstract:PURPOSE:To provide a comprehensive understanding of multi-shot EPI diffusion imaging methods by comparing Readout segmented EPI (RS-EPI) and interleaved EPI (iEPI). MATERIALS AND METHODS:RS-EPI and iEPI were compared on the same 3T scanner. A 2D navigator was used for both RS-EPI and iEPI for phase correction. Signal ...
journal_title:Magnetic resonance imaging
pub_type: 杂志文章
doi:10.1016/j.mri.2017.11.011
更新日期:2018-04-01 00:00:00
abstract::Postero-anterior radiographs and magnetic resonance imaging (MRI) of the chest were performed in nine biopsy proven cases of sarcoidosis. MRI was more sensitive than a postero-anterior chest roentgenogram in detecting hilar and mediastinal adenopathy but less informative in detecting pleural and parenchymal disease. ...
journal_title:Magnetic resonance imaging
pub_type: 杂志文章
doi:10.1016/0730-725x(88)90131-2
更新日期:1988-09-01 00:00:00
abstract::Use of conjugated equine estrogens (CEE) has been linked to smaller regional brain volumes in women aged ≥65 years; however, it is unknown whether this results in a broad-based characteristic pattern of effects. Structural magnetic resonance imaging was used to assess regional volumes of normal tissue and ischemic les...
journal_title:Magnetic resonance imaging
pub_type: 杂志文章,随机对照试验
doi:10.1016/j.mri.2010.12.001
更新日期:2011-05-01 00:00:00
abstract::Functional magnetic resonance imaging (fMRI) of the cortex is a powerful tool for neuroscience research, and its use has been extended into the brainstem and spinal cord as well. However, there are significant technical challenges with extrapolating the developments that have been achieved in the cortex to their use i...
journal_title:Magnetic resonance imaging
pub_type: 杂志文章
doi:10.1016/j.mri.2008.01.038
更新日期:2008-07-01 00:00:00
abstract::Despite intense research on the blood oxygenation level-dependent (BOLD) signal underlying functional magnetic resonance imaging, our understanding of its physiological basis is far from complete. In this study, it was investigated whether the so-called poststimulus BOLD signal undershoot is solely a passive vascular ...
journal_title:Magnetic resonance imaging
pub_type: 杂志文章
doi:10.1016/j.mri.2009.04.003
更新日期:2009-10-01 00:00:00
abstract:PURPOSE:To identify quantitative dynamic contrast-enhanced (DCE)-MRI perfusion parameters indicating tumor response of hepatocellular carcinoma (HCC) to transarterial chemoembolization (TACE). MATERIALS AND METHODS:This prospective pilot study was approved by our institutional review board; written and informed consen...
journal_title:Magnetic resonance imaging
pub_type: 临床试验,杂志文章
doi:10.1016/j.mri.2019.06.017
更新日期:2019-10-01 00:00:00
abstract::Serious adverse reactions following the IV administration of Gd-DTPA (Magnevist, gadopenetate dimeglumine, Berlex Laboratories, Wayne, NJ), although extremely rare, can occur. As yet, there has been no published case of a severe anaphylactoid-type reaction to Gd-DTPA. ...
journal_title:Magnetic resonance imaging
pub_type: 杂志文章
doi:10.1016/0730-725x(90)90019-x
更新日期:1990-01-01 00:00:00
abstract::High field MRI has been applied to high-resolution structural and functional imaging of the brain. Echo planar imaging (EPI) is an ultrafast acquisition technique widely used in diffusion imaging, functional MRI and perfusion imaging. However, it suffers from geometric and intensity distortions caused by static magnet...
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::Pathologically, hippocampal sclerosis (HS) is characterized by neuronal loss and gliosis affecting particularly the pyramidal neurons of CA1, CA3, and CA4 with relative sparing of the CA2 neurons. This can be identified in vivo with magnetic resonance (MR) imaging techniques that can reveal both morphological and sign...
journal_title:Magnetic resonance imaging
pub_type: 杂志文章,评审
doi:10.1016/0730-725x(95)02016-m
更新日期:1995-01-01 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
abstract::Although there is ample evidence in the literature for structural, functional and physiological asymmetries in the two hemispheres of human brain, direct evidence of a similar asymmetry in the in vivo distribution of brain metabolites has been lacking. In this study, the existence of chemical asymmetries in six differ...
journal_title:Magnetic resonance imaging
pub_type: 杂志文章
doi:10.1016/s0730-725x(96)00342-6
更新日期:1997-01-01 00:00:00
abstract::We compared the ability and reproducibility of a fast fluid-attenuated inversion recovery (fast-FLAIR) sequence with and without a magnetization transfer (MT) pulse for detecting and measuring multiple sclerosis (MS)-related abnormalities on magnetic resonance imaging (MRI) scans from 20 patients. The Contrast-to-Nois...
journal_title:Magnetic resonance imaging
pub_type: 杂志文章
doi:10.1016/s0730-725x(98)00182-9
更新日期:1999-04-01 00:00:00
abstract::The objective of this study was to measure T2* values of the normal human lung in vivo during breathhold using a rapid gradient-echo sequence with ultra-short echo times (TE). A sagittal slice of the right lung was imaged in six volunteers with various TE ranging from 0.5 ms to 5 ms using a clinical 1.5 Tesla MR scann...
journal_title:Magnetic resonance imaging
pub_type: 杂志文章
doi:10.1016/s0730-725x(99)00047-8
更新日期:1999-09-01 00:00:00
abstract::T1 and T2 relaxation times are fundamental parameters for signal contrast behaviour in MRI. A number of ex vivo relaxometry studies have dealt with the magnetic field dispersion of T1. By means of multicenter study within the frame of the COMAC BME Concerted Action on Tissue Characterization by MRI and MRS, the in viv...
journal_title:Magnetic resonance imaging
pub_type: 杂志文章,多中心研究
doi:10.1016/0730-725x(93)90202-o
更新日期:1993-01-01 00:00:00
abstract::The purpose of this study was to evaluate a magnetic resonance imaging (MRI) technique for quantifying the proton density water fraction (PDWF) as a biomarker of bone marrow cellularity. Thirty-six human bone marrow specimens from 18 donors were excised and subjected to different measurements of tissue composition: PD...
journal_title:Magnetic resonance imaging
pub_type: 杂志文章
doi:10.1016/j.mri.2014.03.005
更新日期:2014-11-01 00:00:00
abstract::Magnetic field gradients play a fundamental role in MR imaging and localized spectroscopy. The MRI experiment, in particular fast MRI, relies on precise gradient switching, which has become more demanding with the constantly growing number of fast imaging techniques. Here we present a simple MR method to measure the b...
journal_title:Magnetic resonance imaging
pub_type: 杂志文章
doi:10.1016/j.mri.2007.02.002
更新日期:2007-11-01 00:00:00
abstract::The anticancer effect of thiacarpine, a synthetic analogue of the known cytotoxic alkaloid polycarpine isolated from the Pacific ascidian Polycarpa aurata, was investigated in vivo in experiments using mouse solid Ehrlich carcinoma tumor as the target. A high-resolution magnetic resonance imaging (MRI) technique using...
journal_title:Magnetic resonance imaging
pub_type: 杂志文章
doi:10.1016/j.mri.2008.01.014
更新日期:2008-07-01 00:00:00
abstract::The density driven convection phenomenon is expected to have a significant and positive role in CO2 geological storage capacity and safety. The onset and development of density-driven convective on the core scale is critical to understand the mass transfer mechanism. In this paper, laboratory experiments were conducte...
journal_title:Magnetic resonance imaging
pub_type: 杂志文章
doi:10.1016/j.mri.2017.03.004
更新日期:2017-06-01 00:00:00