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

authors： Pavesi L,Balzarini M

更新日期：1996-01-01 00:00:00

abstract：:The advantages of the application of NMR imaging to the studies of enhanced oil recovery methods that include polymer slug flooding, combination slug flooding, and thermal soaking are described. ...

journal_title：Magnetic resonance imaging

authors： Weimin W,Dongjiang L,Wei L

更新日期：1996-01-01 00:00:00

abstract：:The local determination of porosity is an extremely valuable target because of different applications in petrophysics. In fact, obtaining a reliable profile of porosity or saturations could considerably improve the evaluation of transport properties of porous media, especially if applied to multiphase flow test (i.e.,...

journal_title：Magnetic resonance imaging

authors： Borgia GC,Bortolotti V,Dattilo P,Fantazzini P,Maddinelli G

更新日期：1996-01-01 00:00:00

abstract：:The NMR relaxivities of Gd-EOB-DTPA and Gd-DTPA were determined in the kidney and liver of intact male Wistar rats immediately following sacrifice and in vitro in solutions and gels, at 1.5 T using a clinical MR scanner, T1 and T2 values of tissue samples were derived from spin-echo image sequences. Tissue gadolinium ...

journal_title：Magnetic resonance imaging

authors： Shuter B,Tofts PS,Wang SC,Pope JM

更新日期：1996-01-01 00:00:00

abstract：:A new application of the stimulated echo pulse sequence is presented that permits the elucidation of molecular order and dynamics in a time scale between about 100 microseconds and the spin-lattice relaxation time. The technique exploits the influence of dipolar coupling on the quotient of the stimulated and primary e...

journal_title：Magnetic resonance imaging

authors： Grinberg F,Kimmich R,Stapf S

更新日期：1996-01-01 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

authors： Zanni H,Rassem-Bertolo R,Masse S,Fernandez L,Nieto P,Bresson B

更新日期：1996-01-01 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

authors： Mardon D,Prammer MG,Coates GR

更新日期：1996-01-01 00:00:00

abstract：:Diffraction ideas were first introduced to NMR by Mansfield and Grannell. Here we compare "Mansfield (k-space) diffraction" with the "diffusive (q-space) diffraction," noting their similarities and differences. The diffusive-diffraction concept is extremely helpful in elucidating the Pulsed Gradient Spin Echo NMR expe...

journal_title：Magnetic resonance imaging

authors： Callaghan PT

更新日期：1996-01-01 00:00:00

abstract：:This work addresses the special problems of measuring flow velocity distributions in rock by NMR methods. Specifically, these problems are to measure very slow flows as well as flows in the presence of background magnetic field gradients caused by heterogeneities of the rock. We modify a stimulated echo sequence for u...

journal_title：Magnetic resonance imaging

authors： Waggoner RA,Fukushima E

更新日期：1996-01-01 00:00:00

abstract：:The localization of critical structures within the brain is important for the planning of therapeutic strategies. Functional MRI is capable to assess functional response of cortical structures to certain stimuli. The authors present two techniques for functional MRI (fMRI) in a stereotactic set-up. The skull of the pa...

journal_title：Magnetic resonance imaging

authors： Debus J,Essig M,Schad LR,Wenz F,Baudendistel K,Knopp MV,Engenhart R,Lorenz WJ

更新日期：1996-01-01 00:00:00

abstract：:The hippocampal formation possesses an important role in the development and maintenance of short-term memory. In this study, magnetic resonance imaging (MRI) and gross histology were used to quantify the volume of the hippocampal formation in canines. High resolution MRI, using 1 mm thick slices and an intraplanar re...

journal_title：Magnetic resonance imaging

authors： Vullo T,Deo-Narine V,Stallmeyer MJ,Gomez DG,Cahill PT

更新日期：1996-01-01 00:00:00

abstract：:Tissue contrast obtained using fast spin-echo (FSE) and conventional spin-echo (SE) sequences is not identical and a number of mechanisms are thought to contribute to these contrast differences. The effect of stimulated echoes has previously been apparently ruled out as a contributing mechanism. Signal-to-noise ratios...

journal_title：Magnetic resonance imaging

authors： Williams CF,Redpath TW,Smith FW

更新日期：1996-01-01 00:00:00

abstract：:The purpose of the study was to determine whether diffusion-weighted magnetic resonance imaging (DWI) could identify focal lesions that develop in ischemia-sensitive cerebral tissues during reperfusion following global brain ischemia. Localized 1H-Magnetic Resonance Spectroscopy (1H-MRS) measurements were also obtaine...

journal_title：Magnetic resonance imaging

authors： Bizzi A,Righini A,Turner R,Le Bihan D,Bockhorst KH,Alger JR

更新日期：1996-01-01 00:00:00

abstract：:Dynamic contrast-enhanced 2D MR imaging of the breast has shown high sensitivity and specificity for the detection and characterization of breast lesions. We investigated the ability of a dynamic fast 3D MR imaging technique that repeatedly scans the whole breast in 44-s intervals without an interscan delay time to ob...

journal_title：Magnetic resonance imaging

authors： Heiberg EV,Perman WH,Herrmann VM,Janney CG

更新日期：1996-01-01 00:00:00

abstract：:Functional magnetic resonance imaging (fMRI) has found widespread clinical interest. Difficulties in clinical use of the fMRI technique arise, considering the lack of knowledge about activation task performance. This accounts especially for sensorimotor activation studies, in which performance of the sensorimotor acti...

journal_title：Magnetic resonance imaging

authors： Baudendistel K,Schad LR,Wenz F,Essig M,Schröder J,Jahn T,Knopp MV,Lorenz WJ

更新日期：1996-01-01 00:00:00

abstract：:A parametric multiecho variant of proton spectroscopic imaging (SI) is presented using a multiecho SI sequence with uniform phase-encoding of all echoes within each echo train. The acquisition of SI data sets at different echo times (TE) increases the amount of information obtained within the same total measuring time...

journal_title：Magnetic resonance imaging

authors： Dreher W,Leibfritz D

更新日期：1995-01-01 00:00:00

abstract：:The midcalf muscles of eight patients who had peripheral arterial occlusive disease were evaluated by exercise MRI before and after bypass surgery or percutaneous transluminal angioplasty. MRI showed a high intensity of these muscles, especially the posterior muscles, after exercise in all patients before intervention...

journal_title：Magnetic resonance imaging

authors： Yoshioka H,Anno I,Kuramoto K,Matsumoto K,Jikuya T,Itai Y

更新日期：1995-01-01 00:00:00

abstract：:Surface modification of liposomes containing Gd-diethylenetriaminepentaacetyl-phosphatidylethanolamine (Gd-DTPA-PE) as an amphiphilic paramagnetic label influences their contrast properties as MRI agents. Liposomes with the mean diameter ca. 220 nm and 10% mol content of Gd-DTPA-PE were modified with dextran (molecula...

journal_title：Magnetic resonance imaging

authors： Trubetskoy VS,Cannillo JA,Milshtein A,Wolf GL,Torchilin VP

更新日期：1995-01-01 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

authors： Hittmair K,Eckersberger F,Klepetko W,Helbich T,Herold CJ

更新日期：1995-01-01 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

authors： Pattynama PM,Lamb HJ,Van der Velde EA,Van der Geest RJ,Van der Wall EE,De Roos A

更新日期：1995-01-01 00:00:00

abstract：:It has been shown recently that quantitative T2-maps may be measured by acquisition of a series of at least eight T2-weighted SNAPSHOT FLASH images. These measurements require a relaxation delay of 10-15 s after each T2-weighted image for the complete relaxation of the spin system. This results in long measuring times...

journal_title：Magnetic resonance imaging

authors： Deichmann R,Adolf H,Nöth U,Morrissey S,Schwarzbauer C,Haase A

更新日期：1995-01-01 00:00:00

abstract：:Autoradiographic studies have shown that low dose ketamine produces increases in regional glucose utilisation and blood flow in the hippocampus, cerebral cortex, and olfactory lobe in the rat brain, probably due to antagonism at the NMDA receptor. Functional MRI using deoxyhaemoglobin contrast can be used to study cha...

journal_title：Magnetic resonance imaging

authors： Burdett NG,Menon DK,Carpenter TA,Jones JG,Hall LD

更新日期：1995-01-01 00:00:00

abstract：:Diffusion-weighted imaging (DWI) is a relatively new magnetic resonance imaging (MRI) technique that can be used to probe the microenvironment of water. Contrast in DWI depends on properties different from traditional T1 and T2 contrast, and is derived form the translational motion of water molecules. Since it is reas...

journal_title：Magnetic resonance imaging

authors： Helpern JA,Huang N

更新日期：1995-01-01 00:00:00

abstract：:We assessed the magnetic resonance (MR) imaging characteristics of two categories of epileptogenic substrates, neoplasms, and vascular malformations, to determine MR sensitivity and typical imaging features. A blinded retrospective analysis was performed on MR scans from 41 patients who had a neoplasm or vascular malf...

journal_title：Magnetic resonance imaging

authors： Bronen RA,Fulbright RK,Spencer DD,Spencer SS,Kim JH,Lange RC

更新日期：1995-01-01 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

authors： Jackson GD

更新日期：1995-01-01 00:00:00

abstract：:Magnetic resonance imaging (MRI) and localized proton MR spectroscopy (MRS) techniques have been applied for studying different maturation processes in the histochemistry of coconut (Cocos nucifera). Images of the tender and mature coconut are characterized by protons of the aqueous solution present in the cavity and ...

journal_title：Magnetic resonance imaging

authors： Jagannathan NR,Govindaraju V,Raghunathan P

更新日期：1995-01-01 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

authors： Karczmar G,River J,Koretsky AP

更新日期：1995-01-01 00:00:00

abstract：:Macroscopic protonation constants were measured for a series of DTPA mono- and bis-amide ligands using potentiometric titrations. Proton NMR pH titrations yielded protonation populations of the various nitrogen and oxygen basic sites of the ligands for the different protonation stages. Amide formation decreased the ba...

journal_title：Magnetic resonance imaging

authors： Geraldes CF,Urbano AM,Alpoim MC,Sherry AD,Kuan KT,Rajagopalan R,Maton F,Muller RN

更新日期：1995-01-01 00:00:00

abstract：:The application of a raw data-based, operator-independent MR segmentation technique to differentiate boundaries of tumor from edema or hemorrhage is demonstrated. A case of a glioblastoma multiforme with gross and histopathologic correlation is presented. The MR image data set was segmented into tissue classes based o...

journal_title：Magnetic resonance imaging

authors： Phillips WE 2nd,Velthuizen RP,Phuphanich S,Hall LO,Clarke LP,Silbiger ML

更新日期：1995-01-01 00:00:00

abstract：:To investigate whether diffusion-related compartmentalization could be observed in skeletal muscle and whether this compartmentalization was affected by exercising, attenuation curves of signal against diffusion weighting were obtained in skeletal muscle of nine healthy volunteers at rest and after an exercise. Fiftee...

journal_title：Magnetic resonance imaging

authors： Morvan D

更新日期：1995-01-01 00:00:00

abstract：:We compared the efficacy of rapidly acquired magnetization prepared gradient-echo (MP-GRE) sequences with CT and standard MRI pulse sequences for the detection of focal liver lesions. Fourteen patients with 28 focal liver lesions were scanned. TI times of 300, 450, and 600 ms were used. MP-GRE lesion conspicuity was c...

journal_title：Magnetic resonance imaging

authors： Winter TC 3rd,Freeny PC,Nghiem HV,Thomas CR Jr

更新日期：1994-01-01 00:00:00

abstract：:The metabolism of 5-fluorouracil (5-FU) is complex and the reason for the low response rate of tumor patients to 5-FU is currently unknown. The aim of this study was to evaluate whether spectral parameters obtained noninvasively by in vivo 19F nuclear magnetic resonance (NMR) spectroscopy can be used to assess individ...

journal_title：Magnetic resonance imaging

authors： Schlemmer HP,Bachert P,Semmler W,Hohenberger P,Schlag P,Lorenz WJ,van Kaick G

更新日期：1994-01-01 00:00:00

abstract：:The functional value of TurboFLASH MR imaging in the assessment of dynamic contrast enhancement and renal perfusion anomalies was evaluated in seven patients, who also underwent renal scintigraphy in baseline conditions. The basal renograms obtained from MAG-3 scintigraphy (mercapto acetyl triglycine, MAG3-S) and from...

journal_title：Magnetic resonance imaging

authors： Laissy JP,Faraggi M,Lebtahi R,Soyer P,Brillet G,Méry JP,Menu Y,Le Guludec D

更新日期：1994-01-01 00:00:00

abstract：:Brain alcohol was measured in rhesus monkeys (Macaca mulatta) by proton magnetic resonance spectroscopy (MRS) following acute nasogastric alcohol administration (0.8 g/kg). Monkeys were anesthetized with ketamine and xylazine. A 1.5 T whole body imager and a 3-inch surface coil were used to acquire TE 30 and 270 ms sp...

journal_title：Magnetic resonance imaging

authors： Kaufman MJ,Chiu TM,Mendelson JH,Woods BT,Mello NK,Lukas SE,Fivel PA,Wighton LG

更新日期：1994-01-01 00:00:00

abstract：:The objective of this study was to determine the value of magnetic resonance (MR) imaging in diagnosing local recurrence of Ewing sarcoma. We retrospectively reviewed radiographs, Tc99m-methylene diphosphonate (MDP) skeletal scintigraphy, computed tomography scans, and MR studies of 11 patients who had local recurrenc...

journal_title：Magnetic resonance imaging

authors： Kauffman WM,Fletcher BD,Hanna SL,Meyer WH

更新日期：1994-01-01 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

authors： Meyerhoff DJ,MacKay S,Poole N,Dillon WP,Weiner MW,Fein G

更新日期：1994-01-01 00:00:00

abstract：:To assess whether magnetic resonance imaging could assist in diagnosing Ewing sarcoma, we retrospectively analyzed T1- and T2-weighted images of 24 consecutive solitary lytic bone lesions, including 18 cases of histologically proven Ewing sarcoma, and six aggressive-appearing benign lesions including eosinophilic gran...

journal_title：Magnetic resonance imaging

authors： Hanna SL,Fletcher BD,Kaste SC,Fairclough DL,Parham DM

更新日期：1994-01-01 00:00:00

abstract：:The application of NMR Fricke-gelatin dosimetry to the imaging of dose distributions around high dose rate (HDR) radioactive Ir-192 seeds in brachytherapy is presented. The duration of the irradiations required to give changes of the Fricke-gelatin NMR characteristics, which were readily detected by the magnetic reson...

journal_title：Magnetic resonance imaging

authors： Schreiner LJ,Crooks I,Evans MD,Keller BM,Parker WA

更新日期：1994-01-01 00:00:00

abstract：:Radial imaging protocols suitable for monitoring water transport in biopolymer and food materials during processes such as drying and rehydration are developed and tested on a well-characterized model sample. This model consisted of a randomly packed bed of Sephadex beads with varying water content. The results are in...

journal_title：Magnetic resonance imaging

authors： Hills BP,Babonneau F

更新日期：1994-01-01 00:00:00

abstract：:MRI is applied to the visualisation of wetting heterogeneities evidenced by water proton T1 contrast at 0.1 T. Water saturated Fontainebleau sandstone samples were examined either in their original water-wet condition, or after silanation. T1, T2Hahn, and T2CPMG were measured for several porosities. T1 and T2CPMG of h...

journal_title：Magnetic resonance imaging

authors： Guillot G,Chardaire-Rivière C,Bobroff S,Le Roux A,Roussel JC,Cuiec L

更新日期：1994-01-01 00:00:00