abstract：:Surgical specimens from 22 patients with infiltrating ductal carcinoma of the breast were analyzed by high-resolution 1H NMR spectroscopy at 80 and 300 MHz. Results were compared with those obtained from 9 benign (proliferative dysplasia without atypia) breast samples. NMR spectra at 80 MHz showed well-resolved water ...

journal_title：Magnetic resonance in medicine

authors： Bradamante S,Barchiesi E,Pilotti S,Borasi G

更新日期：1988-12-01 00:00:00

abstract：:Dextran-magnetite, a superparamagnetic compound, is a powerful relaxation reagent for sodium. Administered intravenously, it is confined mainly to the vasculature and eliminates the signal from plasma sodium, a significant component of the tissue sodium signal. Applications of dextran-magnetite for in vivo sodium imag...

journal_title：Magnetic resonance in medicine

authors： Summers RM,Joseph PM,Renshaw PF,Kundel HL

更新日期：1988-12-01 00:00:00

abstract：:A comparison between contrast and signal-to-noise ratio (SNR), as obtained by both maximum entropy (ME) and 2DFT reconstruction, is reported for NMR images. Our results show that in the ME elaboration the contrast and SNR are generally increased with respect to the 2DFT elaboration. The magnitude of such an increase d...

journal_title：Magnetic resonance in medicine

authors： De Simone BC,De Luca F,Maraviglia B

更新日期：1988-11-01 00:00:00

abstract：:A new volume selection/spectral editing pulse sequence (VOSING) is presented. The features specific to the technique are that the volume selection and the editing intervals coincide and that no decoupling is necessary. The pulse sequence can be applied under both homo- and heteronuclear conditions. Phantom experiments...

journal_title：Magnetic resonance in medicine

authors： Knüttel A,Rommel E,Clausen M,Kimmich R

更新日期：1988-09-01 00:00:00

abstract：:High-quality, high-resolution, proton-decoupled natural-abundance 13C NMR spectra have been obtained in vitro at 100.6 MHz from unprocessed human pathology specimens of tumors and adjacent nonneoplastic control tissues from lung, colon, and prostate. In these preliminary studies, specific molecular parameters were ide...

journal_title：Magnetic resonance in medicine

authors： Halliday KR,Fenoglio-Preiser C,Sillerud LO

更新日期：1988-08-01 00:00:00

abstract：:The multiexponential behavior of the decay curves obtained in vitro by a Carr-Purcell-Meiboom-Gill (CPMG) sequence from spleens and kidneys of mice is analyzed. The mice were inoculated with the acute lymphocytic P388 leukemic cells and treated with the anticancer drug cis-diamminedichloroplatinum(II), cis-Pt. Kidneys...

journal_title：Magnetic resonance in medicine

authors： François A,Van Gerven L,Atassi G,Eisendrath H,Gielen M,Willem R

更新日期：1988-08-01 00:00:00

abstract：:IVIM MR imaging is a method which generates images of diffusion and perfusion in vivo. Until now, intravoxel incoherent motion (IVIM) images have been obtained using spin-echo sequences with extragradient pulses, resulting in long acquisition times (typically 2 x 8 min 32 s). A new method is proposed here, using stead...

journal_title：Magnetic resonance in medicine

authors： Le Bihan D

更新日期：1988-07-01 00:00:00

abstract：:This communication describes the design and application of a receiver coil operating at liquid nitrogen temperature and intended as a surface coil in a whole-body imager. Its particular application is seen as the external receiver for parasitic internal or implanted detectors. ...

journal_title：Magnetic resonance in medicine

authors： Hall AS,Barnard B,McArthur P,Gilderdale DJ,Young IR,Bydder GM

更新日期：1988-06-01 00:00:00

abstract：:We present a new steady-state imaging sequence, which simultaneously allows in a single acquisition the formation of two MR images with clearly different contrasts. The contrast of the first image is FISP-like, whereas the second image is strongly T2-weighted. In principle the T2 values in the image can be calculated ...

journal_title：Magnetic resonance in medicine

authors： Bruder H,Fischer H,Graumann R,Deimling M

更新日期：1988-05-01 00:00:00

abstract：:Coronal proton and sodium images of control rats and rats with either increased permeability edema produced by intravenous alloxan (300 mg/kg) or increased pressure edema produced by saline infusion (2 ml/min) were obtained. Axial chest CT images were used to monitor the development of pulmonary edema. Immediately aft...

journal_title：Magnetic resonance in medicine

authors： Kundel HL,Shetty A,Joseph PM,Summers RM,Kassab EA,Moore B

更新日期：1988-04-01 00:00:00

abstract：:A method is described for multislice imaging by means of rf pulses which contain a multifrequency excitation spectrum. These pulses label each slice by an individual signal phase and allow the separation of the signals from all the slices by subsequent add/subtract procedures. The image sensitivity corresponds to the ...

journal_title：Magnetic resonance in medicine

authors： Müller S

更新日期：1988-03-01 00:00:00

abstract：:We describe a doubly tuned radiofrequency (RF) local coil probe designed specifically for performing in vivo image-localized spectroscopy. The probe was designed using principles developed in connection with the counter-rotating-current (CRC) and planar-pair loop gap resonators for magnetic resonance imaging (MRI). Th...

journal_title：Magnetic resonance in medicine

authors： Grist TM,Jesmanowicz A,Kneeland JB,Froncisz W,Hyde JS

更新日期：1988-03-01 00:00:00

abstract：:Problems with in vivo proton spectroscopy include strong water and lipid signals, and the very complicated structures of the spectra. Multiple-quantum experiments can be designed to overcome these difficulties. Using a volume selective refocusing technique, one can demonstrate how multiple-quantum experiments can be p...

journal_title：Magnetic resonance in medicine

authors： McKinnon GC,Bosiger P

更新日期：1988-03-01 00:00:00

abstract：:Any number of coils can in principle be used simultaneously and independently in magnetic resonance imaging if the mutual inductances are sufficiently small. Surface coils and head or body coils have equal sensitivity at some crossover depth of the order of 6 to 10 cm. Using a 7.5-cm-diameter surface coil that was int...

journal_title：Magnetic resonance in medicine

authors： Hyde JS,Froncisz W,Jesmanowicz A,Kneeland JB

更新日期：1988-02-01 00:00:00

abstract：:Free induction decay signals are analyzed by fitting a model function directly in the time domain. No starting values are needed for linear model parameters, and omission of corrupted data points poses no problems. A significant gain of accuracy is achieved by imposing prior knowledge about the model parameters. ...

journal_title：Magnetic resonance in medicine

authors： van der Veen JW,de Beer R,Luyten PR,van Ormondt D

更新日期：1988-01-01 00:00:00

abstract：:We describe a versatile NMR probe that is designed for a variety of in vivo spectroscopic studies on small animals in vertical wide-bore magnets. Replaceable brackets enable the coils to be exchanged readily in order to observe 1H, 13C, 31P, and other nuclei, and to carry out double-resonance experiments. Two solenoid...

journal_title：Magnetic resonance in medicine

authors： Lyon RC,Tschudin RG,Daly PF,Cohen JS

更新日期：1988-01-01 00:00:00

abstract：:A novel method for reducing the rf power requirements of selective pulses employed for z magnetization slice inversion in localized NMR spectroscopy is presented. Following slice preparation by the use of frequency-incremented sinc pulses, the slice gradient is reduced, which narrows the frequency width of the slice. ...

journal_title：Magnetic resonance in medicine

authors： Brereton IM,Brooks WM,Marshman MF,Field J,Doddrell DM

更新日期：1987-12-01 00:00:00

abstract：:When developing new techniques for NMR imaging and in vivo spectroscopy it is a major advantage to be able to calculate the magnetization slice profiles, at any point during a pulse sequence in the presence of a field gradient. While this has frequently been done by treating the problem as a number of discrete resonan...

journal_title：Magnetic resonance in medicine

authors： Bulsing JM,Galloway GJ,Brereton IM,Doddrell DM

更新日期：1987-11-01 00:00:00

abstract：:Stimulated-echo localized spectroscopy was combined with phase- and frequency-encoding gradients to obtain "zoom" or magnified images of specific organs in situ. The technique requires neither surface coils nor an imaging coil arrangement that exclusively isolates the target organ. This technique can be readily applie...

journal_title：Magnetic resonance in medicine

authors： Mills P,Chew W,Litt L,Moseley M

更新日期：1987-10-01 00:00:00

abstract：:31P NMR spectroscopy was used to study renal allografts in rats subjected to allograft rejection, cyclosporine toxicity, ischemia, and ureteral obstruction. Parameters of relative peak areas and intracellular pH were accurately distinguished among the different causes of graft dysfunction. Ureteral obstruction was cle...

journal_title：Magnetic resonance in medicine

authors： Shapiro JI,Haug CE,Weil R 3rd,Chan L

更新日期：1987-10-01 00:00:00

abstract：:Fe(III)meso-tetra(4-sulfonatophenyl)porphine (Fe-TPPS4) has been investigated as a potential pH-sensitive nuclear magnetic resonance (NMR) proton image contrast agent. Relaxation rates (1/T1 and 1/T2) of water protons were measured as a function of pH and concentration of Fe-TPPS4 in phosphate-buffered isotonic saline...

journal_title：Magnetic resonance in medicine

authors： Helpern JA,Curtis JC,Hearshen D,Smith MB,Welch KM

更新日期：1987-09-01 00:00:00

abstract：:Spin-echo images of 10 myocardial infarcts in nine mini-pigs were obtained at 30 h, 3 days, and approximately 10 days postinfarction. Infarcts were not detected at all at 30 h in five out of five cases examined. At 3 days postembolization (six cases) one infarct was certainly detected, whilst at 10 days (nine cases) a...

journal_title：Magnetic resonance in medicine

authors： Checkley D,Loveday BE,Waterton JC,Zhu XP,Isherwood I

更新日期：1987-09-01 00:00:00

abstract：:A single slice of z-magnetization is used to generate high-speed images. The slice selection step is achieved using two sin-sinc pulses. This procedure eliminates the need for continual slice gradient reversal, a requirement for the FLASH technique. The RAPID imaging method has less inherent T1 and/or T2 dependence th...

journal_title：Magnetic resonance in medicine

authors： Brooks WM,Brereton IM,Doddrell DM

更新日期：1987-08-01 00:00:00

abstract：:In guinea pigs immunized with myelin basic protein (MBP) in complete Freund's adjuvant, experimental allergic encephalomyelitis (EAE) shows a characteristic clinical and pathological course. This study characterized the proton nuclear magnetic resonance (NMR) properties of the central nervous system prior to the onset...

journal_title：Magnetic resonance in medicine

authors： O'Brien JT,Noseworthy JH,Gilbert JJ,Karlik SJ

更新日期：1987-08-01 00:00:00

abstract：:Aggregation of human erythrocytes at physiological hematocrit by hydroxyethyl starch (HES) was investigated with a 1H nuclear magnetic resonance method which measures the erythrocyte mean water exchange time, tau a. A relationship that takes into account the effect of the aggregate as the water-exchanging unit was use...

journal_title：Magnetic resonance in medicine

authors： Caines GH,Goldstein JH

更新日期：1987-07-01 00:00:00

abstract：:Mumps virus-infected and normal newborn hamster brains were imaged with magnetic resonance (MR) within 24 h after birth and serially scanned. Hydrocephalus developed explosively on Day 6 postinfection and progressed until death occurred soon after Day 10. This study demonstrates the utility of MR in the investigation ...

journal_title：Magnetic resonance in medicine

authors： Narayana PA,Wolinsky JS,Jensen DJ

更新日期：1987-06-01 00:00:00

abstract：:Spatially resolved spectroscopy (SPARS) is a method for obtaining high-resolution NMR spectra of well-defined volumes of human tissues in situ. This method was combined with the Carr-Purcell-Meiboom-Gill multiple-echo sequence for T2, and with inversion recovery for T1 relaxation measurements. Relaxation times obtaine...

journal_title：Magnetic resonance in medicine

authors： Luyten PR,Anderson CM,den Hollander JA

更新日期：1987-05-01 00:00:00

abstract：:An electron paramagnetic resonance image was measured for the first time from in vivo field gradient spectra of a living murine tumor (Cloudman S-91 melanoma in the tail of a DBA-2J mouse) using the paramagnetic nitroxide imaging agent 3-carboxamido-2,2,5,5-tetramethylpyrroline-1-oxyl injected into the tail vein. The ...

journal_title：Magnetic resonance in medicine

authors： Berliner LJ,Fujii H,Wan XM,Lukiewicz SJ

更新日期：1987-04-01 00:00:00

abstract：:The soft tissue contrast obtained in fast imaging using rapidly repeated partial saturation sequences is usually based on differences in T1. We describe here an extension of the method which results in the development of clinically useful T2-based contrast. ...

journal_title：Magnetic resonance in medicine

authors： Young IR,Payne JA,Collins AG,Bydder GM

更新日期：1987-04-01 00:00:00

abstract：:Two NMR experiments are described that use ac field gradients to measure flow velocities. Both experiments perform no spacial localization; instead, fluid velocity is converted to a resonance frequency shift. Thus, by Fourier transformation of a single FID or echo train the distribution of velocities is available. The...

journal_title：Magnetic resonance in medicine

authors： Walton JH,Conradi MS

更新日期：1987-03-01 00:00:00

abstract：:A modified inversion-recovery sequence is introduced which performs subtraction angiography by varying time-of-flight effects of blood flowing into an imaged slab. The selective 180 degrees excitation inverts different regions between measurements to isolate arterial and/or venous blood. On normal human subjects, high...

journal_title：Magnetic resonance in medicine

authors： Nishimura DG,Macovski A,Pauly JM,Conolly SM

更新日期：1987-02-01 00:00:00

abstract：:Cardiac metabolism was studied with 31P NMR in 7 dogs and 4 cats to determine whether animals adapted for different life-styles (stalk and sprint vs endurance running) respond to increased work loads (heart rate X blood pressure product) with different high-energy phosphate kinetics. Hearts were exposed via a left lat...

journal_title：Magnetic resonance in medicine

authors： Ligeti L,Osbakken MD,Clark BJ,Schnall M,Bolinger L,Subramanian H,Leigh JS,Chance B

更新日期：1987-02-01 00:00:00

abstract：:A method is presented for the detection of quadrupole splitting in tissue, where the spectral line splittings are typically unobservable. The method used is a study of the rate of rotation of the flip angle as a function of radiofrequency (rf) amplitude. Our results with samples of skeletal muscle and cat brain indica...

journal_title：Magnetic resonance in medicine

authors： Joseph PM,Summers RM

更新日期：1987-01-01 00:00:00

abstract：:The changes in the response of skeletal muscle to maximal dynamic exercise were investigated in going from a fasted state to a refed state by means of 31P NMR spectroscopy. It was found that in the fasted state, exercise-induced changes in Pi/PCr and in pH were both inhibited, in comparison with those in the refed sta...

journal_title：Magnetic resonance in medicine

authors： Lunt JA,Allen PS,Brauer M,Swinamer D,Treiber EO,Belcastro A,Eccles R,King EG

更新日期：1986-12-01 00:00:00

abstract：:Some of the factors involved in the choice of field strength for NMR imaging are examined. The influences of relaxation times and chemical shift upon image quality and signal-to-noise ratio are highlighted, and power deposition is introduced as a significant factor which may limit the flexibility and information avail...

journal_title：Magnetic resonance in medicine

authors： Hoult DI,Chen CN,Sank VJ

更新日期：1986-10-01 00:00:00

abstract：:A type of local coil (or surface coil) for magnetic resonance imaging and spectroscopy is described in which two circular loops of the same diameter are disposed axially with respect to each other and in which counter rotating currents (CRC) are supported in the two loops. This type of coil has been used for localized...

journal_title：Magnetic resonance in medicine

authors： Froncisz W,Jesmanowicz A,Kneeland JB,Hyde JS

更新日期：1986-08-01 00:00:00

abstract：:Parameter-selective imaging for tissue characterization is performed at low magnetic fields (0.24-0.28 T) employing echo trains with a large number of echoes (less than or equal to 50), high-power pulses, and the projection reconstruction method. Preprocessing of the raw echoes is important for the quality of the echo...

journal_title：Magnetic resonance in medicine

authors： Staemmler M,Gersonde K

更新日期：1986-06-01 00:00:00

abstract：:A modular, user-friendly computer simulation of NMR imaging was created for the DEC VAX computer. This simulation is novel in that complex imaging phenomena, such as chemical shifts and flow, may be easily studied. Other features include spin warp and backprojection imaging, movie generation, and simulation of image c...

journal_title：Magnetic resonance in medicine

authors： Summers RM,Axel L,Israel S

更新日期：1986-06-01 00:00:00

abstract：:A method is demonstrated for detection of magnetization from a selected region within the sensitive volume of a surface coil in a single acquisition. Composite pulses are described which eliminate signals from regions where magnetization is rotated 270 and 450 degrees. There is a loss of 1.3% or less of signal from re...

journal_title：Magnetic resonance in medicine

authors： Karczmar GS,Matson GB,Weiner MW

更新日期：1986-04-01 00:00:00

abstract：:Phosphorus-31 nuclear magnetic resonance spectroscopy (31P NMR) was used to assess the temporal changes of high-energy phosphate metabolites in the region of acute myocardial ischemia of open-chest cats. Eight anesthetized cats were studied following ligation of the left anterior descending coronary artery. Creatine p...

journal_title：Magnetic resonance in medicine

authors： Stein PD,Goldstein S,Sabbah HN,Liu ZQ,Helpern JA,Ewing JR,Lakier JB,Chopp M,LaPenna WF,Welch KM

更新日期：1986-04-01 00:00:00