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 measurements, hydralazine was administered and the measurements repeated. There was always a decrease in blood flow, and a fall in nucleoside triphosphate detected by NMR, after administration of hydralazine. At blood flows in excess of 15 mL 100 g-1 min-1, the nucleoside triphosphate/inorganic phosphate ratio was 1.0 or greater, whereas at flows in the range of 5-12 mL 100 g-1 min-1 the ratio fell to below 0.5, and at flows below 5 mL 100 g-1 min-1 there was no detectable resonance from nucleoside triphosphate.
journal_name
NMR Biomedjournal_title
NMR in biomedicineauthors
Bhujwalla ZM,Tozer GM,Field SB,Proctor E,Busza A,Williams SRdoi
10.1002/nbm.1940030406subject
Has Abstractpub_date
1990-08-01 00:00:00pages
178-83issue
4eissn
0952-3480issn
1099-1492journal_volume
3pub_type
杂志文章abstract::Determination of the apparent diffusion coefficient (ADC) of the prostate in men (n = 60) with raised prostate-specific antigen (PSA) or an abnormal digital rectal examination (DRE) prior to transrectal ultrasound (TRUS) guided biopsy using endorectal DWI is reported. Patients were categorized into different groups ba...
journal_title:NMR in biomedicine
pub_type: 杂志文章
doi:10.1002/nbm.1114
更新日期:2007-08-01 00:00:00
abstract::This introductory article addresses approaches currently in use to process in vivo spectra. First, a brief overview is given of the information content represented by the parameters of MR signals. Subsequently, common steps in the processing of MR spectra such as pre-processing, normalisation and quantification and th...
journal_title:NMR in biomedicine
pub_type: 杂志文章,评审
doi:10.1002/nbm.707
更新日期:2001-06-01 00:00:00
abstract::Phosphorus MRSI (31 P-MRSI) using a spiral-trajectory readout at 7 T was developed for high temporal resolution mapping of the mitochondrial capacity of exercising human skeletal muscle. The sensitivity and localization accuracy of the method was investigated in phantoms. In vivo performance was assessed in 12 volunte...
journal_title:NMR in biomedicine
pub_type: 杂志文章
doi:10.1002/nbm.3662
更新日期:2016-12-01 00:00:00
abstract::Q-ball imaging (QBI) is an imaging technique that is capable of resolving intravoxel fiber crossings; however, the signal readout based on echo-planar imaging (EPI) introduces geometric distortions in the presence of susceptibility gradients. This study proposes an imaging technique that reduces susceptibility distort...
journal_title:NMR in biomedicine
pub_type: 杂志文章
doi:10.1002/nbm.3009
更新日期:2013-12-01 00:00:00
abstract::With a fixed time to acquire a magnetic resonance (MR) image, time can be spent to acquire better spatial resolution with decrease in signal-to-noise ratio (SNR) or decreased resolution with increase in SNR. This resolution/SNR tradeoff at fixed time has been investigated by a visual rater study using images of ex viv...
journal_title:NMR in biomedicine
pub_type: 杂志文章
doi:10.1002/nbm.1359
更新日期:2009-06-01 00:00:00
abstract::Development and evaluation of new anticancer drugs are expedited when minimally invasive biomarkers of pharmacokinetic and pharmacodynamic behaviour are available. Gene-directed enzyme prodrug therapy (GDEPT) is a suicide gene therapy in which the anticancer drug is activated in the tumor by an exogenous enzyme previo...
journal_title:NMR in biomedicine
pub_type: 杂志文章
doi:10.1002/nbm.1375
更新日期:2009-06-01 00:00:00
abstract::Qualitative and quantitative (1) H NMR analysis of lipid extracts of gallbladder tissue in chronic cholecystitis (CC, benign) (n = 14), xanthogranulomatous cholecystitis (XGC, intermediate) (n = 9) and gallbladder cancer (GBC, malignant) (n = 8) was carried out to understand the mechanisms involved in the transformati...
journal_title:NMR in biomedicine
pub_type: 杂志文章
doi:10.1002/nbm.1594
更新日期:2011-05-01 00:00:00
abstract::The purpose of this study was to identify the optimal tracer kinetic model from T1 -weighted dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) data and evaluate whether parameters estimated from the optimal model predict tumor aggressiveness determined from histopathology in patients with papillary thyroi...
journal_title:NMR in biomedicine
pub_type: 杂志文章
doi:10.1002/nbm.4166
更新日期:2020-01-01 00:00:00
abstract:OBJECTIVES:Quantitative MRI (qMRI) of muscles is a promising tool to measure disease progression or to assess therapeutic effects in neuromuscular diseases. Longitudinal imaging studies are needed to show sensitivity of qMRI in detecting disease progression in spinal muscular atrophy (SMA). In this pilot study we there...
journal_title:NMR in biomedicine
pub_type: 杂志文章
doi:10.1002/nbm.4473
更新日期:2021-01-22 00:00:00
abstract:INTRODUCTION:Sarcoidosis is a systemic granulomatous disease affecting in particular the respiratory tract. Cardiac magnetic resonance (CMR), including a measurement of T1 relaxation time, could potentially detect early stadia of sarcoidosis of the heart. The study aims to assess T1 mapping in the detection of early ca...
journal_title:NMR in biomedicine
pub_type: 杂志文章
doi:10.1002/nbm.4388
更新日期:2020-11-01 00:00:00
abstract::Quantification of metabolites is a goal of many biomedical NMR studies. To obtain absolute measurements of metabolite concentrations is often both difficult and time-consuming. In this paper a method for determining metabolite concentrations directly is described and validated. It is applicable to studies of amphibian...
journal_title:NMR in biomedicine
pub_type: 杂志文章
doi:10.1002/nbm.1940050306
更新日期:1992-05-01 00:00:00
abstract::This study tests the hypothesis that brief periods of ischemia result in an increase in myocardial lipids during early reperfusion. We conducted 1H NMR spectroscopy to serially measure myocardial lipids before and after regional ischemia. Localized 1H NMR spectra (spatial resolution of 1.25 mm) were obtained using a o...
journal_title:NMR in biomedicine
pub_type: 杂志文章
doi:10.1002/nbm.1940080206
更新日期:1995-04-01 00:00:00
abstract::The present work aims to show the applicability of an analytical model for the optimisation of the STEAM sequence timing parameters for lactate detection at ultra high-field. The effects of the chemical shift displacement artefact on the J-modulated signal for a weakly-coupled spin system were considered in the three ...
journal_title:NMR in biomedicine
pub_type: 杂志文章
doi:10.1002/nbm.4440
更新日期:2020-11-02 00:00:00
abstract::Cerebrovascular reactivity (CVR) can give insight into the cerebrovascular function. CVR can be estimated by measuring a blood-oxygen-level-dependent (BOLD) response combined with breath-holding (BH). The reproducibility of this technique has been addressed and existing studies have focused on short-term reproducibili...
journal_title:NMR in biomedicine
pub_type: 杂志文章
doi:10.1002/nbm.4195
更新日期:2020-03-01 00:00:00
abstract::The goal of this study was to validate metabolite quantification at short TE, with particular focus on how to best account for the macromolecular signal contribution. A robust, short-TE PRESS protocol is presented, which allows reliable quantification, in vivo, of metabolite signals at 3 T in human brain. Water suppre...
journal_title:NMR in biomedicine
pub_type: 杂志文章
doi:10.1002/nbm.1219
更新日期:2008-06-01 00:00:00
abstract::The aim of this study was to acquire the transient MRI signal of hyperpolarized tracers and their metabolites efficiently, for which specialized imaging sequences are required. In this work, a multi-echo balanced steady-state free precession (me-bSSFP) sequence with Iterative Decomposition with Echo Asymmetry and Leas...
journal_title:NMR in biomedicine
pub_type: 杂志文章
doi:10.1002/nbm.4291
更新日期:2020-06-01 00:00:00
abstract::Following the impetus of early clinical and experimental investigations, in vivo and in vitro MRS studies of tumours pointed in the eighties to the possible significance of signals arising from phospholipid (PL) precursors and catabolites as novel biochemical indicators of in vivo tumour progression and response to th...
journal_title:NMR in biomedicine
pub_type: 杂志文章,评审
doi:10.1002/(sici)1099-1492(199911)12:7<413::aid-nbm58
更新日期:1999-11-01 00:00:00
abstract::The purpose of the present study was to characterize the metabolic profile of the visual cortex in streptozotocin-induced Type 1 diabetic rats by means of in vivo proton MRS. Several metabolite concentration ratios in the visual cortex were calculated. In addition, postmortem histologic analyses for retinal ganglion c...
journal_title:NMR in biomedicine
pub_type: 杂志文章
doi:10.1002/nbm.3783
更新日期:2017-11-01 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
pub_type: 杂志文章
doi:10.1002/nbm.1734
更新日期:2012-02-01 00:00:00
abstract::Hyperpolarised (HP) (13)C NMR allows enzymatic activity to be probed in real time in live biological systems. The use of in vitro models gives excellent control of the cellular environment, crucial in the understanding of enzyme kinetics. The increased conversion of pyruvate to lactate in cancer cells has been well st...
journal_title:NMR in biomedicine
pub_type: 杂志文章
doi:10.1002/nbm.3341
更新日期:2015-08-01 00:00:00
abstract::It is generally accepted that tumour microcirculation, blood flow, oxygen and nutrient supply, tissue pH distribution, and the bioenergetic status--factors which are usually closely linked and which define the so-called metabolic microenvironment--can markedly influence the therapeutic response of malignant tumours to...
journal_title:NMR in biomedicine
pub_type: 杂志文章,评审
doi:10.1002/nbm.1940050505
更新日期:1992-09-01 00:00:00
abstract::Traditional methods of measuring magnetization in magnetic fluid samples, such as vibrating sample magnetometry (VSM), are typically limited to maximum field strengths of about 1 T. This work demonstrates the ability of MRI to measure the magnetization associated with two commercial MRI contrast agents at 3 T by compa...
journal_title:NMR in biomedicine
pub_type: 杂志文章
doi:10.1002/nbm.1412
更新日期:2009-10-01 00:00:00
abstract::Central obesity is the hallmark of a number of non-inheritable disorders. The advent of imaging techniques such as MRI has allowed for a fast and accurate assessment of body fat content and distribution. However, image analysis continues to be one of the major obstacles to the use of MRI in large-scale studies. In thi...
journal_title:NMR in biomedicine
pub_type: 杂志文章
doi:10.1002/nbm.3432
更新日期:2015-12-01 00:00:00
abstract::Chemical exchange saturation transfer (CEST) imaging of amine protons exchanging at intermediate rates and whose chemical shift is around 2 ppm may provide a means of mapping creatine. However, the quantification of this effect may be compromised by the influence of overlapping CEST signals from fast-exchanging amines...
journal_title:NMR in biomedicine
pub_type: 杂志文章
doi:10.1002/nbm.3756
更新日期:2017-10-01 00:00:00
abstract::The elimination of so-called background fields is an essential step in phase MRI and quantitative susceptibility mapping (QSM). Background fields, which are caused by sources outside the region of interest (ROI), are often one to two orders of magnitude stronger than tissue-related field variations from within the ROI...
journal_title:NMR in biomedicine
pub_type: 杂志文章,评审
doi:10.1002/nbm.3604
更新日期:2017-04-01 00:00:00
abstract::The current study aims to evaluate the feasibility of creatine (Cr) chemical exchange saturation transfer (CEST)-weighted MRI at 7 T in the human brain by optimizing the saturation pulse parameters and computing contrast using a Z-spectral fitting approach. The Cr-weighted (Cr-w) CEST contrast was computed from phanto...
journal_title:NMR in biomedicine
pub_type: 杂志文章
doi:10.1002/nbm.4176
更新日期:2019-12-01 00:00:00
abstract::In this study we aimed to assess the effects of continuous formalin fixation on diffusion and relaxation metrics of the ex vivo porcine heart at 7 T. Magnetic resonance imaging was performed on eight piglet hearts using a 7 T whole body system. Hearts were measured fresh within 3 hours of cardiac arrest followed by im...
journal_title:NMR in biomedicine
pub_type: 杂志文章
doi:10.1002/nbm.4298
更新日期:2020-07-01 00:00:00
abstract::Increased pulmonary lactate production is correlated with severity of lung injury and outcome in acute respiratory distress syndrome (ARDS) patients. This study was conducted to investigate the relative contributions of inflammation and hypoxia to the lung's metabolic shift to glycolysis in an experimental animal mode...
journal_title:NMR in biomedicine
pub_type: 杂志文章
doi:10.1002/nbm.4380
更新日期:2020-11-01 00:00:00
abstract::In this study, Blood Oxygenation Level Dependent (BOLD) contrast in the detection of human brain activation was compared between spin-echo and gradient-echo echo-planar sequences at 1.5 T. Time course series of spin-echo and gradient-echo images containing the primary motor cortex were collected during rest (no finger...
journal_title:NMR in biomedicine
pub_type: 杂志文章
doi:10.1002/nbm.1940070104
更新日期:1994-03-01 00:00:00
abstract::Cerebral ischemia provokes tissue damage by two major patho-physiological mechanisms. Direct cell necrosis is induced by diminished access of neurons and glia to essential nutrients such as glucose and oxygen leading to energy failure. A second factor of cellular loss is related to the activation of immune-competent c...
journal_title:NMR in biomedicine
pub_type: 杂志文章
doi:10.1002/nbm.770
更新日期:2002-06-01 00:00:00