Abstract：
:The applicability of the synthetic manganese porphyrin MnTPPS as tumor-selective MRI-contrast agent for brain tumors was investigated quantitatively by in vivo relaxometry. To exclude toxic effects of side products, the purification method for MnTPPS was improved. As a result, MnTPPS+Cl- (free acid) with a purity of more than 99.8% was obtained. For the in vivo quantification of the contrast effect the magnetization M(0) and the transversal relaxation time T2 were evaluated in different regions of rat brains with or without implanted gliomas and in temporal muscle. Measurements were performed before and after the application of MnTPPS. The ratio of the magnetization M(0) (TR = 3.5 sec) of the tissue under investigation and the contralateral striatum was defined as contrast ratio Rc(0). Without MnTPPS Rc(0) of edema (0.93 +/- 0.08) and tumor (0.91 +/- 0.07) did not differ from normal brain tissue (corpus callosum: 0.96 +/- 0.07; cortex: 0.98 +/- 0.05). T2 of edema (110 +/- 12 msec) and intracranial tumor (93 +/- 7 msec) were significantly longer than in normal tissue (corpus callosum: 73 +/- 8 msec; parietal cortex: 75 +/- 6 msec; striate nucleus: 78 +/- 7 msec, p < .01). Two hours after the injection of MnTPPS, magnetization of neoplastic tissue was selectively enhanced (TR = 3.5 sec), and T2 was reduced. The smallest dose of 0.06 mmol/kg body weight (bw) increased Rc(0) to 1.12 +/- 0.04, and 0.38 mmol/kg to 1.30 +/- 0.13 (p < .01). T2 of tumor decreased to 85 +/- 6 msec after 0.06 mmol/kg and to 65 +/- 6 msec after 0.38 mmol/kg bw.(ABSTRACT TRUNCATED AT 250 WORDS)
journal_name
Magn Reson Imagingjournal_title
Magnetic resonance imagingauthors
Bockhorst K,Hoehn-Berlage M,Ernestus RI,Tolxdorf T,Hossmann KAdoi
10.1016/0730-725x(93)90007-zsubject
Has Abstractpub_date
1993-01-01 00:00:00pages
655-63issue
5eissn
0730-725Xissn
1873-5894pii
0730-725X(93)90007-Zjournal_volume
11pub_type
杂志文章abstract：UNLABELLED:The conventional diagnostic work-up of a patient suspected of having a vascular cause for stridor, or dysphagia, includes esophagography and bronchoscopy to delineate the abnormal structure without imaging the structure itself. Cine-angiography is regarded as the golden standard, but is not routinely perform...
journal_title：Magnetic resonance imaging
pub_type： 杂志文章
doi：10.1016/s0730-725x(97)00245-2
更新日期：1998-01-01 00:00:00
abstract：:The spin-echo nuclear magnetic resonance (NMR) technique together with paramagnetic ion doping are used to study structural parameters of plant samples, such as restricted dimensions, and cell interconnection both through membranes and by cell contact by studying simultaneous restricted diffusion and intercellular wat...
journal_title：Magnetic resonance imaging
pub_type： 杂志文章
doi：10.1016/s0730-725x(98)00053-8
更新日期：1998-06-01 00:00:00
abstract：:The biodistribution and relative molar effectiveness of the ionic (GdCl3) and chelated (Gd-DTPA) forms of gadolinium (Gd) to enhance proton relaxation rates in rat kidney, liver and spleen were evaluated. Rats were given intravenous injections of either GdCl3 (100 mumol/kg) or Gd-DTPA (178 mumol/kg). Gd-DTPA was prima...
journal_title：Magnetic resonance imaging
pub_type： 杂志文章
doi：10.1016/0730-725x(87)90023-3
更新日期：1987-01-01 00:00:00
abstract：:Deep brain stimulation (DBS) is used increasingly in the field of movement disorders. The implanted electrodes create not only a prior risk to patient safety during MRI, but also a unique opportunity in the collection of functional MRI data conditioned by direct neural stimulation. We evaluated MRI-related heating for...
journal_title：Magnetic resonance imaging
pub_type： 杂志文章
doi：10.1016/j.mri.2005.02.007
更新日期：2005-05-01 00:00:00
abstract：:The value of NMR spectrometry as a way to understand the porosity and permeability of rocks is well documented. Other more esoteric parameters, such as restrictive diffusion, grain size distribution, and fluid viscosities have received less notice but are also available from the NMR measurements as laboratory studies ...
journal_title：Magnetic resonance imaging
pub_type： 杂志文章
doi：10.1016/0730-725x(94)91537-7
更新日期：1994-01-01 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：:Multi-echo pulse sequences for producing T2-weighted images in much reduced imaging times have recently been developed for routine clinical use. A number of recent articles have described the contrast obtained with fast spin-echo (FSE) sequences and have generally indicated that they depict tissues very similarly to c...
journal_title：Magnetic resonance imaging
pub_type： 杂志文章,评审
doi：10.1016/0730-725x(92)90001-g
更新日期：1992-01-01 00:00:00
abstract：:Diabetic retinopathy (DR) is one of a major complication of type 1 diabetes mellitus (T1DM) and a leading cause of blindness. Evidence of animal study has shown that it is not only a microvasucular lesion of the eye, but also a neurodegeneration disease of the visual system. However, the in vivo imaging evidence of ax...
journal_title：Magnetic resonance imaging
pub_type： 杂志文章
doi：10.1016/j.mri.2020.05.003
更新日期：2020-09-01 00:00:00
abstract：:Most modern techniques for functional magnetic resonance imaging (fMRI) rely on blood-oxygen-level-dependent (BOLD) contrast as the basic principle for detecting neuronal activation. However, the measured BOLD effect depends on a transfer function related to neurophysiological changes accompanying electrical neural ac...
journal_title：Magnetic resonance imaging
pub_type： 杂志文章
doi：10.1016/j.mri.2008.02.006
更新日期：2008-11-01 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
abstract：:An efficient method for obtaining longitudinal relaxation time (T1) maps is based on acquiring two spoiled gradient recalled echo (SPGR) images in steady states with different flip angles, which has also been extended, with additional acquisitions, to obtain a tissue water content (M0) map. Several factors, including ...
journal_title：Magnetic resonance imaging
pub_type： 杂志文章
doi：10.1016/j.mri.2013.08.001
更新日期：2013-12-01 00:00:00
abstract：PURPOSE:The purpose was to validate diffusion-weighted imaging (DWI) in the assessment of hepatic metastases compared with superparamagnetic iron oxide (SPIO)-enhanced magnetic resonance imaging. MATERIALS AND METHODS:For 21 consecutive patients with 160 metastases from extrahepatic malignancy and 25 benign focal lesi...
journal_title：Magnetic resonance imaging
pub_type： 杂志文章
doi：10.1016/j.mri.2011.12.007
更新日期：2012-05-01 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：:Functional magnetic resonance imaging (fMRI) was used to investigate the spatial distribution of cortical activation in frontal and parietal lobes during auditory and visual oddball tasks in 10 healthy subjects. The purpose of the study was to compare activation within auditory and visual modalities and identify commo...
journal_title：Magnetic resonance imaging
pub_type： 杂志文章
doi：10.1016/s0730-725x(00)00128-4
更新日期：2000-06-01 00:00:00
abstract：:NMR spectroscopy is applied to study microstructure of calcium silicate hydrates present in cement and concrete. It is shown that 29Si NMR gives information on the siliceous skeleton of the hydrates. 1H NMR, using CRAMPS techniques, allows to discriminate between protons linked to silicon atoms or to calcium atoms. A ...
journal_title：Magnetic resonance imaging
pub_type： 杂志文章
doi：10.1016/s0730-725x(96)00211-1
更新日期：1996-01-01 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：: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：:Currently, the North American symptomatic carotid endarterectomy trial, European carotid surgery trial, and common carotid method are used to measure the carotid stenosis for determining candidates for carotid endarterectomy using the projection angiography from different modalities such as digital subtraction angiogr...
journal_title：Magnetic resonance imaging
pub_type： 杂志文章
doi：10.1016/j.mri.2004.01.007
更新日期：2004-04-01 00:00:00
abstract：:Spiral acquisition schemes offer unique advantages such as flow compensation, efficient k-space sampling and robustness against motion that make this option a viable choice among other non-Cartesian sampling schemes. For this reason, the main applications of spiral imaging lie in dynamic magnetic resonance imaging suc...
journal_title：Magnetic resonance imaging
pub_type： 杂志文章,评审
doi：10.1016/j.mri.2010.03.036
更新日期：2010-07-01 00:00:00
abstract：PURPOSE:To evaluate the use of the double-echo steady-state (DESS) sequence for acquiring high-resolution breast images with diffusion and T2 weighting. MATERIALS AND METHODS:Phantom scans were used to verify the T2 and diffusion weighting of the DESS sequence. Image distortion was evaluated in volunteers by comparing...
journal_title：Magnetic resonance imaging
pub_type： 杂志文章
doi：10.1016/j.mri.2013.12.014
更新日期：2014-05-01 00:00:00
abstract：:The effects of varying the inversion or excitation RF pulse flip angles on image contrast and imaging time have been investigated in IR imaging theoretically, with phantoms and with normal volunteers. Signal intensity in an IR pulse sequence as a function of excitation, inversion and refocusing pulse flip angles was c...
journal_title：Magnetic resonance imaging
pub_type： 杂志文章
doi：10.1016/0730-725x(92)90481-e
更新日期：1992-01-01 00:00:00
abstract：:We used magnetic resonance imaging (MRI) and water-suppressed proton MR spectroscopic imaging (1H MRSI) to study the effects of human immunodeficiency virus (HIV) infection on the brain. Our recent in vivo finding of lower N-acetylaspartate (NAA), a putative marker of neurons, in the supraventricular brain of cognitiv...
journal_title：Magnetic resonance imaging
pub_type： 杂志文章
doi：10.1016/0730-725x(94)92460-0
更新日期：1994-01-01 00:00:00
abstract：:Measurements of arterial input function (AIF) can have large systematic errors at standard contrast agent doses in dynamic contrast enhanced MRI (DCE-MRI). We compared measured AIFs from low dose (AIFLD) and standard dose (AIFSD) contrast agent injections, as well as the AIF derived from a muscle reference tissue and ...
journal_title：Magnetic resonance imaging
pub_type： 杂志文章
doi：10.1016/j.mri.2015.10.025
更新日期：2016-02-01 00:00:00
abstract：PURPOSE:To evaluate the correlation between the pancreatic exocrine insufficiency estimated by cine-dynamic MRCP using spatially selective IR pulse and the severity stages (modified Cambridge classification) based on morphological changes of the pancreatic duct in patients with suspected chronic pancreatitis. MATERIAL...
journal_title：Magnetic resonance imaging
pub_type： 杂志文章
doi：10.1016/j.mri.2017.12.007
更新日期：2018-05-01 00:00:00
abstract：INTRODUCTION:Glioma is the most common type of the primary CNS tumor. Radiotherapy is an important treatment measure after surgery. However, its highly invasive character is the main reason of postoperative recurrence. The aim of the study was to probe the correlation between the invasion ability and the metabolite cha...
journal_title：Magnetic resonance imaging
pub_type： 杂志文章
doi：10.1016/j.mri.2016.05.009
更新日期：2016-10-01 00:00:00
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：:Magnetic resonance (MR) imaging has been shown to provide accurate measurements of right ventricular (RV) volumes and myocardial mass. The purpose of this study was to evaluate the reproducibility of MR imaging, which in clinical practice may be as important as its absolute accuracy. The reproducibility of MR imaging ...
journal_title：Magnetic resonance imaging
pub_type： 杂志文章
doi：10.1016/0730-725x(94)00076-f
更新日期：1995-01-01 00:00:00
abstract：:L-2-Chloropropionic acid (L-CPA) is selectively toxic to rat cerebellar granule cells; necrosis is first observed about 36 hours after administration of L-CPA (750 mg/kg p.o.) becoming more marked by 48 h. Parallel to the onset of cell death an increase in cerebellar water content and sodium concentration has been rep...
journal_title：Magnetic resonance imaging
pub_type： 杂志文章
doi：10.1016/s0730-725x(01)00231-4
更新日期：2001-02-01 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：:New methods for acquiring and processing gradient NMR well log data enable signals from gas, light oil, and water to be unambiguously separated and, in many cases, quantified. These methods exploit the combined effects of T1-based and diffusion-based contrast on log response. T1 contrast, which separates the water and...
journal_title：Magnetic resonance imaging
pub_type： 杂志文章
doi：10.1016/s0730-725x(96)00162-2
更新日期：1996-01-01 00:00:00
