Electro-optic probe for real-time assessments of RF electric field produced in an MRI scanner: Feasibility tests at 3 and 4.7 T.

abstract：:In this study the conjugated macromolecular ligand, diethylenetriaminepentaacetic acid (DTPA)-amide-dextran, was synthesized by attaching DTPA to the dextran macromolecule (M(r) approximately 6000) by a covalent amide bond. Subsequently, DTPA-amide-dextran was complexed with either of the two lanthanide metal ions dys...

journal_title：NMR in biomedicine

authors： Chu WJ,Elgavish GA

更新日期：1995-06-01 00:00:00

abstract：:Early imaging or blood biomarkers of tumor response is needed to customize anti-tumor therapy on an individual basis. This study evaluates the sensitivity and relevance of five potential MRI biomarkers. Sixty nude rats were implanted with human glioma cells (U-87 MG) and randomized into three groups: one group receive...

journal_title：NMR in biomedicine

authors： Lemasson B,Christen T,Tizon X,Farion R,Fondraz N,Provent P,Segebarth C,Barbier EL,Genne P,Duchamp O,Remy C

更新日期：2011-06-01 00:00:00

abstract：:In vitro (1)H MRS of human bile has shown potential in the diagnosis of various hepatopancreatobiliary (HPB) diseases. Previously, in vivo (1)H MRS of human bile in gallbladder using a 1.5 T scanner demonstrated the possibility of quantification of choline-containing phospholipids (chol-PLs). However, other lipid comp...

journal_title：NMR in biomedicine

authors： Mohajeri S,Ijare OB,Bezabeh T,King SB,Thomas MA,Minuk G,Lipschitz J,Kirkpatrick I,Smith M,Smith IC

更新日期：2014-10-01 00:00:00

abstract：:High-resolution MR imaging (312 microns in plane resolution) and MR spectroscopy (0.36 cm3 nominal voxel) have been performed on human frontal cortex using a 3 in surface coil. Localized proton spectra have been obtained from contiguous 6 x 6 x 10 mm voxels using one-dimensional phase encoding, TR 2000 ms and TE 31 ms...

journal_title：NMR in biomedicine

authors： López-Villegas D,Kimura H,Tunlayadechanont S,Lenkinski RE

更新日期：1996-10-01 00:00:00

abstract：:A recent analysis of the optimization of magnetization transfer experiments to estimate first-order rate constants is extended to the design of experiments for measuring these constants and T1 when both parameters are initially unknown. When the number of measurement times is fixed, an optimal design will consist of a...

journal_title：NMR in biomedicine

authors： Katki H,Weiss GH,Kiefer JE,Taitelbaum H,Spencer RG

更新日期：1996-05-01 00:00:00

abstract：:Chemical exchange saturation transfer (CEST)-derived, pH-weighted, amide proton transfer (APT) MRI has shown promise in animal studies for the prediction of infarction risk in ischemic tissue. Here, APT MRI was translated to patients with acute stroke (1-24 h post-symptom onset), and assessments of APT contrast, perfu...

journal_title：NMR in biomedicine

authors： Tietze A,Blicher J,Mikkelsen IK,Østergaard L,Strother MK,Smith SA,Donahue MJ

更新日期：2014-02-01 00:00:00

abstract：:The purpose of this work was to assess the reproducibility of percentage of ventilated lung volume (PV) measured from hyperpolarized (HP) (3)He and (1)H anatomical images acquired in the same breath-hold when compared with PV measured from (3)He and (1)H images from separate breath-holds. Volumetric (3)He ventilation ...

journal_title：NMR in biomedicine

authors： Horn FC,Tahir BA,Stewart NJ,Collier GJ,Norquay G,Leung G,Ireland RH,Parra-Robles J,Marshall H,Wild JM

更新日期：2014-12-01 00:00:00

abstract：:A method to extract shapes of bubble polyhedra from three-dimensional nuclear magnetic resonance image data of foam has been developed. The method consists of four steps: first, to compute series of maximum intensity projection images from the three-dimensional NMR image data of foam to visualize the network structure...

journal_title：NMR in biomedicine

authors： Kashiwagi K,Kose K

更新日期：1997-01-01 00:00:00

abstract：:Proton magnetic resonance spectroscopy (MRS) was employed to determine the concentrations of N-acetylaspartate (NAA), total creatine (tCr), choline-containing compounds (Cho), myo-inositol (Ins), glucose (Glc), and lactate (Lac) in rat brain before and after 10 days of oral supplementation of 2.6 g Cr-monohydrate per ...

journal_title：NMR in biomedicine

authors： Michaelis T,Wick M,Fujimori H,Matsumura A,Frahm J

更新日期：1999-08-01 00:00:00

abstract：:Proton NMR spectroscopy of biological fluids has produced interesting results lately. We used the technique to investigate the effects of cryopreservation on primary porcine hepatocytes as successful cryopreservation of primary porcine hepatocytes is of importance to the development of bioartificial liver support syst...

journal_title：NMR in biomedicine

authors： Dabos KJ,Parkinson JA,Hewage C,Nelson LJ,Sadler IH,Hayes PC,Plevris JN

更新日期：2002-05-01 00:00:00

abstract：:T2 of NAA, creatine and choline-containing compounds were measured in posterior frontal white matter and occipital grey matter in 10 healthy human volunteers. Decay curves comprised signals from eight TE times ranging from 30 to 800 ms with TR 2000 ms acquired with a PRESS sequence on a 1.5 T clinical scanner. Simulat...

journal_title：NMR in biomedicine

authors： Brief EE,Whittall KP,Li DK,MacKay AL

更新日期：2005-02-01 00:00:00

abstract：:Under normal conditions, the heart mainly relies on fatty acid oxidation to meet its energy needs. Changes in myocardial fuel preference are noted in the diseased and failing heart. The magnetic resonance signal enhancement provided by spin hyperpolarization allows the metabolism of substrates labeled with carbon-13 t...

journal_title：NMR in biomedicine

authors： Yoshihara HAI,Bastiaansen JAM,Karlsson M,Lerche MH,Comment A,Schwitter J

更新日期：2020-03-01 00:00:00

abstract：:Current functional MRI (fMRI) approaches assess underlying neuronal activity through monitoring the related local variations in cerebral blood oxygenation, blood volume and blood flow. This vascular response is likely to vary across brain regions and across individuals, depending on the composition of the local vascul...

journal_title：NMR in biomedicine

authors： Driver ID,Andoh J,Blockley NP,Francis ST,Gowland PA,Paus T

更新日期：2015-05-01 00:00:00

abstract：:In MR elastography, it is common to use an elastic model for the tissue's response in order to interpret the results properly. More complex models, such as viscoelastic, fractional viscoelastic, poroelastic, or poroviscoelastic ones, are also used. These models appear at first sight to be very different, but here it i...

journal_title：NMR in biomedicine

authors： Holm S

更新日期：2018-10-01 00:00:00

abstract：:Blood flow and phosphorus metabolites have been measured simultaneously in the murine RIF-1 tumour in vivo. Blood flow was measured using the H2 washout technique and 31P NMR spectroscopy was used to measure high energy phosphates, inorganic phosphate and intracellular pH within the tumour. Following NMR and flow meas...

journal_title：NMR in biomedicine

authors： Bhujwalla ZM,Tozer GM,Field SB,Proctor E,Busza A,Williams SR

更新日期：1990-08-01 00:00:00

abstract：:One of the major goals of hyperpolarized-gas MR imaging has been to obtain (129)Xe dissolved-phase images in humans. Since the dissolved-phase signal is much weaker than the gas-phase signal, highly optimized MR pulse sequences are required to obtain adequate images during a single breath-hold. In particular, a solid ...

journal_title：NMR in biomedicine

authors： Ruppert K,Brookeman JR,Hagspiel KD,Driehuys B,Mugler JP 3rd

更新日期：2000-06-01 00:00:00

abstract：:Encoding of spatial information in magnetic resonance imaging is conventionally accomplished by using magnetic field gradients. During gradient encoding, the position in k-space is determined by a time-integral of the gradient field, resulting in a limitation in imaging speed due to either gradient power or secondary ...

journal_title：NMR in biomedicine

authors： Wright SM,McDougall MP

更新日期：2009-11-01 00:00:00

abstract：:MRI and MRS in small rodents demand very high sensitivity. Cryogenic transmit/receive radiofrequency probes (CryoProbes) designed for (1) H MRI of mouse brain provide an attractive option for increasing the performance of small-animal MR systems. As the Larmor frequency of (13) C nuclei is four times lower than that f...

journal_title：NMR in biomedicine

authors： Sack M,Wetterling F,Sartorius A,Ende G,Weber-Fahr W

更新日期：2014-06-01 00:00:00

abstract：:In the unstimulated brain energy is primarily supplied by the oxidation of glucose. However the oxygen-to-glucose index (OGI), which is the ratio of metabolic rates of oxygen to glucose, CMR(O2)/CMR(glc), diverges from the theoretical value of 6 as activity is increased. In vivo measurements of brain lactate show its ...

journal_title：NMR in biomedicine

authors： Shulman RG,Hyder F,Rothman DL

更新日期：2001-11-01 00:00:00

abstract：PURPOSE:To develop a novel respiratory motion compensated three-dimensional (3D) cardiac magnetic resonance fingerprinting (cMRF) approach for whole-heart myocardial T1 and T2 mapping from a free-breathing scan. METHODS:Two-dimensional (2D) cMRF has been recently proposed for simultaneous, co-registered T1 and T2 mapp...

journal_title：NMR in biomedicine

authors： Cruz G,Jaubert O,Qi H,Bustin A,Milotta G,Schneider T,Koken P,Doneva M,Botnar RM,Prieto C

更新日期：2020-10-01 00:00:00

abstract：:Vessel size index (VSI), a parameter related to the distribution of vessel diameters, may be estimated using two MRI approaches: (i) dynamic susceptibility contrast (DSC) MRI following the injection of a bolus of Gd-chelate. This technique is routinely applied in the clinic to assess intracranial tissue perfusion in p...

journal_title：NMR in biomedicine

authors： Pannetier N,Lemasson B,Christen T,Tachrount M,Troprès I,Farion R,Segebarth C,Rémy C,Barbier EL

更新日期：2012-02-01 00:00:00

abstract：:We have developed a reliable, reproducible model of hypoxia in the gerbil. 1H and 31P NMR spectroscopy demonstrates that cerebral energy metabolism is very resistant to hypoxia. Cerebral blood flow (measured by hydrogen clearance) began to increase when the arterial oxygen tension (paO2) was reduced to 40-50 mm Hg, an...

journal_title：NMR in biomedicine

authors： Allen K,Busza AL,Crockard HA,Gadian DG

更新日期：1992-01-01 00:00:00

abstract：:Quantitative magnetisation transfer imaging (qMTI) is an extension of conventional MT techniques and allows the measurement of parameters that reflect tissue ultrastructure through the properties of macromolecule-bound protons; these include the bound proton fraction and the relaxation times of free and bound proton p...

journal_title：NMR in biomedicine

authors： Tozer DJ,Rees JH,Benton CE,Waldman AD,Jäger HR,Tofts PS

更新日期：2011-06-01 00:00:00

abstract：:Acute hypoxia (transient cycles of hypoxia-reoxygenation) is known to occur in solid tumors and is generally believed to be caused by tumor blood flow instabilities. It was recently demonstrated that T2*-weighted (T2*w) gradient echo (GRE) MRI is a powerful non-invasive method for investigating periodic changes in tum...

journal_title：NMR in biomedicine

authors： Baudelet C,Cron GO,Ansiaux R,Crokart N,DeWever J,Feron O,Gallez B

更新日期：2006-02-01 00:00:00

abstract：:The intimal and medial linings of the pulmonary artery consist largely of vascular endothelial cells (VECs) and vascular smooth muscle cells (VSMCs), respectively. The migration of these cell types to a potential tissue-engineered pulmonary valve (TEPV) implant process is therefore of interest in understanding the val...

journal_title：NMR in biomedicine

authors： Ramaswamy S,Schornack PA,Smelko AG,Boronyak SM,Ivanova J,Mayer JE Jr,Sacks MS

更新日期：2012-03-01 00:00:00

abstract：PURPOSE:To investigate the feasibility of using multiple flip angles in dynamic contrast enhanced (DCE) MRI to reduce the uncertainty in estimation of intracellular water lifetime (τi ). METHODS:Numerical simulation studies were conducted to assess the uncertainty in estimation of τi using dynamic contrast enhanced MR...

journal_title：NMR in biomedicine

authors： Zhang J,Kim SG

更新日期：2019-11-01 00:00:00

abstract：:Progress in the development of non-proton NMR applications in medical research has been hampered by the generally low sensitivity of these nuclides as well as the lack of instrumentation readily available for studying these spins. For example, custom head coils suitable for sodium imaging of the human head are either ...

journal_title：NMR in biomedicine

authors： Lim KO,Wolff S,Balaban RS

更新日期：1989-09-01 00:00:00

abstract：:Diffusion tensor MRI (DTI) is a method for the noninvasive assessment of cellular organization and integrity in vivo. In this study, in vivo DTI was performed to demonstrate its ability to reflect photoreceptor cell alignment in adult C57BL/6 wild-type mice. Age-matched retinal degeneration 1 (rd1) mice were employed ...

journal_title：NMR in biomedicine

authors： Chen J,Wang Q,Chen S,Wickline SA,Song SK

更新日期：2011-06-01 00:00:00

abstract：:Reconstruction of MRI data is based on exact knowledge of all magnetic field dynamics, since the interplay of RF and gradient pulses generates the signal, defines the contrast and forms the basis of resolution in spatial and spectral dimensions. Deviations caused by various sources, such as system imperfections, delay...

journal_title：NMR in biomedicine

authors： Brunner DO,Dietrich BE,Çavuşoğlu M,Wilm BJ,Schmid T,Gross S,Barmet C,Pruessmann KP

更新日期：2016-09-01 00:00:00

abstract：:At the high field strength of 7 T, in vivo spectra of the human brain with exceptional spectral quality sufficient to quantify 16 metabolites have been obtained previously only in the occipital lobe. However, neurochemical abnormalities associated with many brain disorders are expected to occur in brain structures oth...

journal_title：NMR in biomedicine

authors： Marjańska M,Auerbach EJ,Valabrègue R,Van de Moortele PF,Adriany G,Garwood M

更新日期：2012-02-01 00:00:00