Abstract:
:Net ATP production rates in exercising human muscle were calculated from 31P MRS kinetic data collected with 1-8 s time resolution. During the exercise, the muscle output was measured using a force transducer. Muscle output (force/unit volume) is then divided by the calculated net ATP used to estimate the ATP cost of force production. These measurements have been performed using an exercise protocol of isometric maximum voluntary contraction of the gastrocnemius/soleus muscle group. Results show that by the end of 30 s of exercise, total ATP production and ATP cost of force production had stabilized and remained constant (within the measurement errors) until the end of the 2-min period. The results also demonstrate that either the ATP cost of force production in the human gastrocnemius/soleus is lower in the first second than at any other time in the 2-min window which was investigated, or that the ATP production is being underestimated at the later time points. These data on ATP production rates, and the data relating to ATP cost of force production in muscle will aid in understanding the causes of muscle failure as well as the progression and treatment of muscle disease.
journal_name
NMR Biomedjournal_title
NMR in biomedicineauthors
Boska Mdoi
10.1002/nbm.1940040404subject
Has Abstractpub_date
1991-08-01 00:00:00pages
173-81issue
4eissn
0952-3480issn
1099-1492journal_volume
4pub_type
杂志文章abstract::Transmit efficiency specifies the amplitude of the magnetic resonance excitation field produced over a region of interest with respect to the radiofrequency (RF) power deposited in the sample. This metric is highly important at ultra-high field magnetic resonance imaging (≥7 T), where excitation inhomogeneities and el...
journal_title:NMR in biomedicine
pub_type: 杂志文章
doi:10.1002/nbm.4383
更新日期:2020-11-01 00:00:00
abstract::This paper describes the use of off-resonance saturation to further manipulate the blood oxygenation level dependent (BOLD) contrast of fMRI. A customized narrow bandwidth radiofrequency pulse, applied with a range of frequency offsets prior to selection of each slice, was designed and incorporated into a gradient ech...
journal_title:NMR in biomedicine
pub_type: 杂志文章
doi:10.1002/(sici)1099-1492(199706/08)10:4/5<208::aid-
更新日期:1997-06-01 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::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
pub_type: 杂志文章
doi:10.1002/nbm.3359
更新日期:2016-09-01 00:00:00
abstract::The significance of NMR water diffusion measurements performed at short diffusion times (< 10 ms) for brain tissue is examined. An apparent restriction to diffusion for both healthy and cytotoxically edematous tissue is shown: cytotoxic edema lengthens the diffusion time at which this phenomenon is visible. The dramat...
journal_title:NMR in biomedicine
pub_type: 杂志文章
doi:10.1002/nbm.1940070703
更新日期:1994-11-01 00:00:00
abstract::The physiological status of anesthetized rats greatly influences blood oxygenation level dependent (BOLD) functional magnetic resonance imaging (fMRI). Monitoring of physiological parameters, particularly partial pressure of carbon dioxide (pCO(2)) levels in the blood, is therefore an important part in the design and ...
journal_title:NMR in biomedicine
pub_type: 杂志文章
doi:10.1002/nbm.978
更新日期:2005-11-01 00:00:00
abstract::Spin-exchange NMR techniques enable the measurement of the rates of exchange of solutes between chemically or physically distinct sites in reactions taking place at chemical equilibrium. The time scale of the events that are able to be investigated lies in the neighbourhood of 1 s. The earliest studies in this area of...
journal_title:NMR in biomedicine
pub_type: 杂志文章,评审
doi:10.1002/nbm.1940030303
更新日期:1990-06-01 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::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 development of parallel imaging, parallel transmission describes the use of multiple RF transmit coils. Parallel transmission can be applied to improve RF excitation, in particular, multidimensional, spatially selective RF excitation. For instance, parallel transmission is able to shorten spatially selec...
journal_title:NMR in biomedicine
pub_type: 杂志文章,评审
doi:10.1002/nbm.1049
更新日期:2006-05-01 00:00:00
abstract::MRS provides a valuable tool for the non-invasive detection of brain γ-aminobutyric acid (GABA) in vivo. GABAergic dysfunction has been observed in the aging cerebellum. The study of cerebellar GABA changes is of considerable interest in understanding certain age-related motor disorders. However, little is known about...
journal_title:NMR in biomedicine
pub_type: 杂志文章
doi:10.1002/nbm.3381
更新日期:2015-10-01 00:00:00
abstract::One of the most commonly used methods for in vivo MRS detection of γ-aminobutyric acid (GABA) is the MEGA-point-resolved spectroscopy (MEGA-PRESS) technique. However, accurate quantification of GABA using MEGA-PRESS is complicated by spectral co-editing of macromolecular resonances. In this article, a new pulse sequen...
journal_title:NMR in biomedicine
pub_type: 杂志文章
doi:10.1002/nbm.1688
更新日期:2011-12-01 00:00:00
abstract::Polycystic kidney disease (PKD) is a life-threatening disease that leads to a grotesque enlargement of the kidney and significant loss of function. Several imaging studies with MRI have demonstrated that cyst size in polycystic kidneys can determine disease severity and progression. In the present study, we found that...
journal_title:NMR in biomedicine
pub_type: 杂志文章
doi:10.1002/nbm.3281
更新日期:2015-05-01 00:00:00
abstract::133Cs NMR is a valuable tool for non-invasively probing biological systems. As a congener of potassium, it accumulates in the intracellular space, primarily through the action of the Na+-K+ pump (ATPase). In addition, it is possible to resolve the MR signal of 133Cs in different tissue compartments on the basis of che...
journal_title:NMR in biomedicine
pub_type: 杂志文章,评审
doi:10.1002/nbm.909
更新日期:2005-04-01 00:00:00
abstract::Several obstacles usually confound a straightforward perfusion analysis using dynamic-susceptibility contrast-based magnetic resonance imaging (DSC-MRI). In this work, it became possible to eliminate some of these sources of error by combining a multiple gradient-echo technique with parallel imaging (PI): first, the l...
journal_title:NMR in biomedicine
pub_type: 杂志文章
doi:10.1002/nbm.1107
更新日期:2007-06-01 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
pub_type: 临床试验,杂志文章
doi:10.1002/nbm.916
更新日期:2005-02-01 00:00:00
abstract::The possibility of quantifying the superimposed signal of glutamate and glutamine (Glx) and its components by ¹H magnetic resonance spectroscopy (MRS) in the spinal cord is an exciting challenge with important clinical applications in neurological conditions. The spinal cord is a particularly difficult region of inter...
journal_title:NMR in biomedicine
pub_type: 杂志文章
doi:10.1002/nbm.2867
更新日期:2013-03-01 00:00:00
abstract::Cross-talk between adipose tissue and liver is disturbed in the metabolic syndrome. Moreover, the relative fatty acid composition of adipose and liver fat is poorly characterized. Long-TE (1)H MRS can determine the unsaturation and polyunsaturation of adipose tissue. The aim of this study was to use long-TE (1)H MRS t...
journal_title:NMR in biomedicine
pub_type: 杂志文章
doi:10.1002/nbm.1580
更新日期:2011-04-01 00:00:00
abstract::Magnetic resonance imaging (MRI) in pregnancy is commonly undertaken in the left lateral tilt (LLT) position to prevent inferior vena cava (IVC) compression and supine hypotensive events, although this may be suboptimal for image quality. The supine position may also have an adverse effect on fetal well-being. The spi...
journal_title:NMR in biomedicine
pub_type: 杂志文章
doi:10.1002/nbm.4475
更新日期:2021-01-21 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::13C MRS was installed on a clinical scanner at 1.5 T in order to facilitate integrated MR examinations of human brain disorders. Using a simplified protocol, (1-(13)C) glucose and/or (1-(13)C) acetate were administered orally or by intravenous infusion. (13)C spectra of diagnostic quality were acquired in more than 10...
journal_title:NMR in biomedicine
pub_type: 杂志文章,评审
doi:10.1002/nbm.852
更新日期:2003-10-01 00:00:00
abstract::This review assesses the progress of NMR in the field of hemorheology, i.e., the assessment of the mechanical and physical characteristics of flowing blood. The review deals with the intrinsic rheological properties of the red cell and its constituents (membrane, cytoplasm), which are dominant in the microcirculation,...
journal_title:NMR in biomedicine
pub_type: 杂志文章,评审
doi:10.1002/nbm.1940020102
更新日期:1989-06-01 00:00:00
abstract::Human tumor and skeletal muscle tissue was studied by means of in vivo 1H, 31P, and 13C MRS. The examinations were performed with a 1.5 T whole-body MR scanner equipped with a second RF system. Localized 1H and broadband proton-decoupled 31P and 13C MR spectra were obtained in measurement times of 5, 10 and 33 min, re...
journal_title:NMR in biomedicine
pub_type: 杂志文章
doi:10.1002/nbm.1940050402
更新日期:1992-07-01 00:00:00
abstract::The sodium-calcium exchanger (NCX) is one of the transporters contributing to the control of intracellular calcium (Ca(2+)) concentration by normally mediating net Ca(2+) efflux. However, the reverse mode of the NCX can cause intracellular Ca(2+) concentration overload, which exacerbates the myocardial tissue injury r...
journal_title:NMR in biomedicine
pub_type: 杂志文章
doi:10.1002/nbm.1414
更新日期:2009-10-01 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
pub_type: 杂志文章
doi:10.1002/nbm.4370
更新日期:2020-10-01 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
pub_type: 杂志文章
doi:10.1002/nbm.4243
更新日期:2020-03-01 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::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::Metabolomic studies by NMR spectroscopy are increasingly employed for a variety of biomedical applications. A very standardized 1D proton NMR protocol is generally employed for data acquisition, associated with multivariate statistical tests. Even if targeted approaches have been proposed to quantify metabolites from ...
journal_title:NMR in biomedicine
pub_type: 杂志文章
doi:10.1002/nbm.1816
更新日期:2012-08-01 00:00:00
abstract::This review highlights various magnetic resonance image (MRI) segmentation algorithms that employ pattern recognition. The procedures are grouped into two categories: low- to intermediate-level, and high-level image processing. The former consists of grey level histogram analysis, texture definition, edge identificati...
journal_title:NMR in biomedicine
pub_type: 杂志文章,评审
doi:10.1002/(sici)1099-1492(199806/08)11:4/5<157::aid-
更新日期:1998-06-01 00:00:00