Abstract:
:The extent of reaction of 153Gd-radiolabeled Gd(L) chelates with 25 mM CO23- (25 mF), PO34-, Zn2+ and Cu2+ at pH 7 was determined for L = EDTA, DTPA, DOTA, HP-DO3A, and DO3A. Gd(EDTA)- and Gd(DTPA)2- reacted (greater than 20% in 10 min) with Cu2+ and Zn2+ in the presence of PO34-. These double replacement reactions yielded precipitated GdPO4 and chelated Cu(L). Gd(HP-DO3A), Gd(DO3A) and Gd(DOTA)- were inert to reaction with all four ions at room temperature (less than or equal to 1% reaction detected). The thermodynamic binding constants of the ligands for Gd3+ and Cu2+ were found to be equal (10(20) M-1) for DO3A, while DOTA and HP-DO3A favored Gd3+ over Cu2+ by greater than or equal to 10(2) M-1. The low order of reactivity of Gd(DOTA)- and Gd(HP-DO3A) was anticipated by the binding constants, but the lack of reactivity of Gd(DO3A) is attributed to kinetic inertia. This latter property, desirable in MRI contrast agents, is promoted by the conformational stability of the tetraazacyclododecane macrocycle, which forms the backbone of the ligand. It is concluded that this class of chelates is exceptionally inert in solutions of endogenously available ions, and that thermodynamics alone is an insufficient predictor of the reactivity of the highly inert Gd complexes based on the tetraazamacrocycle.
journal_name
Magn Reson Imagingjournal_title
Magnetic resonance imagingauthors
Tweedle MF,Hagan JJ,Kumar K,Mantha S,Chang CAdoi
10.1016/0730-725x(91)90429-psubject
Has Abstractpub_date
1991-01-01 00:00:00pages
409-15issue
3eissn
0730-725Xissn
1873-5894pii
0730-725X(91)90429-Pjournal_volume
9pub_type
杂志文章abstract::The dependence of BOLD signal change (BSC) on baseline hematocrit is in the process of being characterized, primarily using conventional Gradient Echo (GE) echo planar imaging (EPI). We describe the first empiric exploration of this relationship using, in addition to GE, Spin Echo (SE) and two Asymmetric Spin Echo EPI...
journal_title:Magnetic resonance imaging
pub_type: 杂志文章
doi:10.1016/s0730-725x(03)00083-3
更新日期:2003-07-01 00:00:00
abstract::We propose a novel processing method for reducing shading artifacts in quantitative susceptibility mapping (QSM) for prostate imaging. In the conventional method, calculation errors in the boundary regions between water and fat cause shading artifacts that degrade the image quality for QSM. In the proposed method, wat...
journal_title:Magnetic resonance imaging
pub_type: 杂志文章
doi:10.1016/j.mri.2019.11.006
更新日期:2020-02-01 00:00:00
abstract::Radial acquisitions can suffer from trajectory errors leading to reduced image quality. Here we present a new method of trajectory correction that uses all spokes of a radial acquisition and compare it to an existing method that uses a two-spoke pre-scan calibration. For both methods, estimates of the necessary shifts...
journal_title:Magnetic resonance imaging
pub_type: 杂志文章
doi:10.1016/j.mri.2014.04.006
更新日期:2014-09-01 00:00:00
abstract::The evaluation of a solitary pulmonary nodule (SPN) is one of the most frequently encountered challenges in thoracic radiology. In addition to a "state-of-the-art" evaluation of SPNs with CT and biopsy techniques, recently the assessment of the enhancement characteristics with iodinized contrast agents has shown its p...
journal_title:Magnetic resonance imaging
pub_type: 杂志文章
doi:10.1016/0730-725x(95)02010-q
更新日期:1995-01-01 00:00:00
abstract::An inductively coupled surface coil for imaging the rat spine at 7 T is described. This planar circular probe was made from microwave substrate to limit the size of the coil and to minimize the magnetic susceptibility. The surface coil was used as a single transmit/receive coil and as a receive-only coil with a birdca...
journal_title:Magnetic resonance imaging
pub_type: 杂志文章
doi:10.1016/0730-725x(92)90447-8
更新日期:1992-01-01 00:00:00
abstract::Multisite quantitative magnetic resonance imaging (qMRI) of volume requires a small isotropic point spread-function (PSF) that is spatially, temporarily, and platform invariant. A phantom which will allow rapid assessment of this metric throughout the imaged volume without repositioning will assist certification of im...
journal_title:Magnetic resonance imaging
pub_type: 杂志文章
doi:10.1016/j.mri.2009.07.002
更新日期:2010-02-01 00:00:00
abstract::Pulsed field gradient (PFG) nuclear magnetic resonance (NMR) and microimaging experiments have been performed to study the diffusion of liquid alkanes into a variety of semicrystalline polyethylene (PE) samples. The results highlight the importance of the crystalline phase in controlling the diffusion process in terms...
journal_title:Magnetic resonance imaging
pub_type: 杂志文章
doi:10.1016/s0730-725x(98)00032-0
更新日期:1998-06-01 00:00:00
abstract::Today, patients with alveolar rhabdomyosarcoma have a favorable prognosis with a survival rate of more than 80%, due to modern radiotherapy. However, those patients with secondary meningeal involvement are still afflicted with a mortality rate of 90% unless a different therapeutic approach is taken. We report a case o...
journal_title:Magnetic resonance imaging
pub_type: 杂志文章
doi:10.1016/0730-725x(93)90035-c
更新日期:1993-01-01 00:00:00
abstract::We studied the effect of hydralazine on tumor blood volume fraction and microvascular random flow velocity magnitude by IVIM weighted MRI in conjunction with dynamic Gd-DTPA-Albumin enhanced MRI. Blood volume fraction maps were obtained from the dynamic Gd-DTPA-Albumin enhanced MRI measurements. The average blood volu...
journal_title:Magnetic resonance imaging
pub_type: 杂志文章
doi:10.1016/s0730-725x(01)00431-3
更新日期:2001-10-01 00:00:00
abstract::Percentage of lipid content of 22 adrenal cortex lesions and their water proton longitudinal relaxation time were measured in vitro at 60 MHz. Although water relaxation times obtained on benign and malignant samples overlap each other, measurements of the percentage of lipids performed on the same tissues allow us to ...
journal_title:Magnetic resonance imaging
pub_type: 杂志文章
doi:10.1016/0730-725x(87)90123-8
更新日期:1987-01-01 00:00:00
abstract:PURPOSE:Investigation of the feasibility of the R2⁎ mapping techniques by using latest theoretical models corrected for confounding factors and optimized for signal to noise ratio. THEORY AND METHODS:The improvement of the performance of state of the art magnetic resonance imaging (MRI) relaxometry algorithms is chall...
journal_title:Magnetic resonance imaging
pub_type: 杂志文章
doi:10.1016/j.mri.2016.08.006
更新日期:2017-01-01 00:00:00
abstract::The application of MRI-visible paramagnetic tracers to reveal in vivo connectivity can provide important subject-specific information for multisite, multielectrode intracortical recordings in combined behavioral and physiology experiments. To establish the use of such tracers in the nonhuman primate, we recently compa...
journal_title:Magnetic resonance imaging
pub_type: 杂志文章
doi:10.1016/j.mri.2005.12.031
更新日期:2006-05-01 00:00:00
abstract::This work discusses the effect of sampling time on noise, signal-to-noise and contrast-to-noise ratios in magnetic resonance imaging. A simple imaging experiment is performed to demonstrate the effect of sampling time on noise, confirming theoretical expectations that doubling the sampling time while decreasing the re...
journal_title:Magnetic resonance imaging
pub_type: 杂志文章
doi:10.1016/0730-725x(87)90481-4
更新日期:1987-01-01 00:00:00
abstract::In congenital diaphragmatic hernia (CDH), lung hypoplasia and secondary pulmonary hypertension are the major causes of death and severe disability. Based on new therapeutic strategies survival rates could be improved to up to 80%. However, after surgical repair of CDH, long-term follow-up of these pediatric patients i...
journal_title:Magnetic resonance imaging
pub_type: 杂志文章
doi:10.1016/j.mri.2015.08.003
更新日期:2015-12-01 00:00:00
abstract::With the recent development of integrated positron emission tomography-magnetic resonance imaging (PET-MRI) scanners, new possibilities for quantitative molecular imaging of cancer are realized. However, the practical advantages and potential clinical benefits of the ability to record PET and MRI data simultaneously m...
journal_title:Magnetic resonance imaging
pub_type: 杂志文章,评审
doi:10.1016/j.mri.2012.06.001
更新日期:2012-11-01 00:00:00
abstract::A phase encoding method for imaging of chemical shift or magnetic field distributions is described. The method utilizes the spin-echo principle and the time period between signal collection and excitation is constant but the time period between excitation and the 180 degrees pulse is varied by constant steps. The meth...
journal_title:Magnetic resonance imaging
pub_type: 杂志文章
doi:10.1016/0730-725x(85)90253-x
更新日期:1985-01-01 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::The development of NMR diffusion imaging and diffusion tensor imaging (DTI) has offered the possibility of studying the porous structures beyond anatomical imaging. In fact, random molecular motions, within tissue components, probe tissue microstructures. Up to now, the DTI method was mainly used to investigate cerebr...
journal_title:Magnetic resonance imaging
pub_type: 杂志文章
doi:10.1016/j.mri.2004.11.018
更新日期:2005-02-01 00:00:00
abstract::T2-weighted images are considered the most sensitive for lesion detection at high field; however, long imaging time is problematic. Accordingly, the authors compared four breath-hold T2 or T2* weighted sequences comprising T2*-weighted FLASH, T2*-weighted PSIF, T2-weighted rapid spin echo (RASE), and T2-weighted Turbo...
journal_title:Magnetic resonance imaging
pub_type: 杂志文章
doi:10.1016/0730-725x(92)90371-6
更新日期:1992-01-01 00:00:00
abstract::Quantitative analysis has tremendous but mostly unrealized potential in healthcare to support objective and accurate interpretation of the clinical imaging. In 2008, the National Cancer Institute began building the Quantitative Imaging Network (QIN) initiative with the goal of advancing quantitative imaging in the con...
journal_title:Magnetic resonance imaging
pub_type: 杂志文章
doi:10.1016/j.mri.2012.05.001
更新日期:2012-11-01 00:00:00
abstract::In pharmacological magnetic resonance imaging (phMRI) with anesthetized animals, there is usually only a single time window to observe the dynamic signal change to an acute drug administration since subsequent drug injections are likely to result in altered response properties (e.g., tolerance). Unlike the block-desig...
journal_title:Magnetic resonance imaging
pub_type: 杂志文章
doi:10.1016/j.mri.2008.02.020
更新日期:2008-11-01 00:00:00
abstract:INTRODUCTION:Pharmacokinetic parameters derived from dynamic contrast-enhanced MRI (DCE-MRI) data are sensitive to acquisition and post-processing techniques, which makes it difficult to compare results obtained using different methods. In particular, one of the most important factors affecting estimation of model para...
journal_title:Magnetic resonance imaging
pub_type: 杂志文章
doi:10.1016/j.mri.2018.05.007
更新日期:2018-10-01 00:00:00
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journal_title:Magnetic resonance imaging
pub_type: 杂志文章
doi:10.1016/s0730-725x(98)00132-5
更新日期:1998-12-01 00:00:00
abstract::In the breast carcinamas, sentinel lymph node biopsy (SLNB) attracts attention as technique to be settled by axillary lymph node metastasis, but existence of a false negative case is a problem. Equivalent cross relaxation rate image (ECRI) is the measurement method that we can evaluate a change of organization structu...
journal_title:Magnetic resonance imaging
pub_type: 杂志文章
doi:10.1016/s0730-725x(03)00208-x
更新日期:2003-11-01 00:00:00
abstract:OBJECTIVE:To develop and validate a large field of view phantom and quality assurance software tool for the assessment and characterization of geometric distortion in MRI scanners commissioned for radiation therapy planning. MATERIALS AND METHODS:A purpose built phantom was developed consisting of 357 rods (6mm in dia...
journal_title:Magnetic resonance imaging
pub_type: 杂志文章,评审
doi:10.1016/j.mri.2015.04.003
更新日期:2015-09-01 00:00:00
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
pub_type: 杂志文章
doi:10.1016/0730-725x(84)90193-0
更新日期:1984-01-01 00:00:00
abstract::Prostate MRI is an important tool to diagnose and characterize cancer. High local sensitivity and good parallel imaging performance are of paramount importance for diagnostic quality and efficiency. The purpose of this work was to evaluate stacked resonators as part of a surface receiver array for prostate MRI at 3 Te...
journal_title:Magnetic resonance imaging
pub_type: 杂志文章
doi:10.1016/j.mri.2018.07.010
更新日期:2018-11-01 00:00:00
abstract::Dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) is often used to examine vascular function in malignant tumors and noninvasively monitor drug efficacy of antivascular therapies in clinical studies. However, complex numerical methods used to derive tumor physiological properties from DCE-MRI images can b...
journal_title:Magnetic resonance imaging
pub_type: 杂志文章
doi:10.1016/j.mri.2012.09.007
更新日期:2013-05-01 00:00:00
abstract::Blood circulation is an important determinant of the biodistribution of superparamagnetic iron oxide nanoparticles. Here we present a magnetic resonance imaging (MRI) technique based on the use of ultrafast echo times (UTE) for the noninvasive determination of blood half-lives at high particle concentrations, when con...
journal_title:Magnetic resonance imaging
pub_type: 杂志文章
doi:10.1016/j.mri.2015.06.017
更新日期:2015-11-01 00:00:00
abstract::The nonhuman primate brain study provides important supplemental means for human brain exploration since the two species share close anatomical and functional similarities. MR diffusion tensor imaging (DTI) in human brain has revealed exquisite details of brain structures especially in the brain white matter. However,...
journal_title:Magnetic resonance imaging
pub_type: 杂志文章
doi:10.1016/j.mri.2008.07.004
更新日期:2009-04-01 00:00:00