Temporal scaling properties and spatial synchronization of spontaneous blood oxygenation level-dependent (BOLD) signal fluctuations in rat sensorimotor network at different levels of isoflurane anesthesia.

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

authors： Jochimsen TH,Newbould RD,Skare ST,Clayton DB,Albers GW,Moseley ME,Bammer R

更新日期：2007-06-01 00:00:00

abstract：:The signal decay with increasing b-factor at fixed echo time from brain tissue in vivo has been measured using a line scan Stejskal-Tanner spin echo diffusion approach in eight healthy adult volunteers. The use of a 175 ms echo time and maximum gradient strengths of 10 mT/m allowed 64 b-factors to be sampled, ranging ...

journal_title：NMR in biomedicine

authors： Mulkern RV,Gudbjartsson H,Westin CF,Zengingonul HP,Gartner W,Guttmann CR,Robertson RL,Kyriakos W,Schwartz R,Holtzman D,Jolesz FA,Maier SE

更新日期：1999-02-01 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：: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：:Quantitative susceptibility mapping (QSM) is a recently developed MRI technique that provides a quantitative measure of tissue magnetic susceptibility. To compute tissue magnetic susceptibilities based on gradient echoes, QSM requires reliable unwrapping of the measured phase images and removal of contributions caused...

journal_title：NMR in biomedicine

authors： Li W,Avram AV,Wu B,Xiao X,Liu C

更新日期：2014-02-01 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

authors： Gottschalk M,Lamalle L,Segebarth C

更新日期：2008-06-01 00:00:00

abstract：:Acute kidney injury (AKI) in mice caused by sustained ischemia followed by reperfusion is associated with acute tubular necrosis and renal dysfunctional blood flow. Although the principal role of the kidney is the maintenance of acid-base balance, current imaging approaches are unable to assess this important paramete...

journal_title：NMR in biomedicine

authors： Longo DL,Cutrin JC,Michelotti F,Irrera P,Aime S

更新日期：2017-07-01 00:00:00

abstract：:High-energy phosphate metabolism, which allows the synthesis and regeneration of adenosine triphosphate (ATP), is a vital process for neuronal survival and activity. In particular, creatine kinase (CK) serves as an energy reservoir for the rapid buffering of ATP levels. Altered CK enzyme activity, reflecting compromis...

journal_title：NMR in biomedicine

authors： Jeong EK,Sung YH,Kim SE,Zuo C,Shi X,Mellon EA,Renshaw PF

更新日期：2011-08-01 00:00:00

abstract：:Bone contains a significant fraction of water that is not detectable with ordinary Cartesian imaging sequences. The advent of ultra-short echo-time (UTE) methods has allowed the recovery of this submillisecond T(2)* water. In this work, we have developed a new three-dimensional hybrid-radial ultra-short echo-time (3D ...

journal_title：NMR in biomedicine

authors： Rad HS,Lam SC,Magland JF,Ong H,Li C,Song HK,Love J,Wehrli FW

更新日期：2011-08-01 00:00:00

abstract：:Studies of cholesteryl ester transfer protein (CETP) function in lipoprotein mixtures pose many difficulties by conventional biochemical methods. For instance, studies on the effects of CETP on the composition of apolipoprotein B containing lipoproteins (very low and low density lipoproteins) in lipoprotein mixtures a...

journal_title：NMR in biomedicine

authors： Korhonen A,Ala-Korpela M,Liinamaa MJ,Jokisaari J,Kesäniemi YA,Savolainen MJ

更新日期：1997-10-01 00:00:00

abstract：:Chronic pain is a major problem for the individual and for society. Despite a range of drugs being available to treat chronic pain, only inadequate pain relief can be achieved for many patients. There is therefore a need for the development of new analgesic compounds. The assessment of pain depends to date entirely on...

journal_title：NMR in biomedicine

authors： Schweinhardt P,Bountra C,Tracey I

更新日期：2006-10-01 00:00:00

abstract：:Phosphorus-31 magnetic resonance spectroscopy ((31)P-MRS) has gained much interest in schizophrenia research in recent years since it allows the non-invasive measurement of high-energy phosphates and phospholipids in vivo. However, until now only differences in metabolite concentrations between certain brain areas of ...

journal_title：NMR in biomedicine

authors： Riehemann S,Volz HP,Wenda B,Hübner G,Rössger G,Rzanny R,Sauer H

更新日期：1999-12-01 00:00:00

abstract：:An outline is presented of metabolite-specific in vivo NMR spectroscopy (particularly in brain). It reviews from a physical spectroscopist's perspective, the need for and the methods of observation of, individual metabolite resonances. ...

journal_title：NMR in biomedicine

authors： Allen PS,Thompson RB,Wilman AH

更新日期：1997-12-01 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

authors： Katscher U,Börnert P

更新日期：2006-05-01 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

authors： Chou MC,Huang TY,Chung HW,Hsieh TJ,Chang HC,Chen CY

更新日期：2013-12-01 00:00:00

abstract：:Brain activation studies in humans have shown the dynamic nature of neuronal N-acetylaspartate (NAA) and N-acetylaspartylglutamate (NAAG) based on changes in their MRS signals in response to stimulation. These studies demonstrated that upon visual stimulation there was a focal increase in cerebral blood flow (CBF) and...

journal_title：NMR in biomedicine

authors： Baslow MH,Cain CK,Sears R,Wilson DA,Bachman A,Gerum S,Guilfoyle DN

更新日期：2016-12-01 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

authors： Bandettini PA,Wong EC,Jesmanowicz A,Hinks RS,Hyde JS

更新日期：1994-03-01 00:00:00

abstract：:The application of diffusion tensor imaging (DTI) to the evaluation of developing brain remains an area of active investigation. This review focuses on the changes in DTI parameters which accompany both brain maturation and injury. The two primary pieces of information available from DTI studies-water apparent diffusi...

journal_title：NMR in biomedicine

authors： Neil J,Miller J,Mukherjee P,Hüppi PS

更新日期：2002-11-01 00:00:00

abstract：:This study investigated the association between the total choline (tCho) concentration and the clinical characteristics and biomarker status of breast cancer. Sixty-two patients with breast cancer, 1.5  cm or larger in size on MR images, were studied. The tCho concentration was correlated with the MRI features, contra...

journal_title：NMR in biomedicine

authors： Chen JH,Mehta RS,Baek HM,Nie K,Liu H,Lin MQ,Yu HJ,Nalcioglu O,Su MY

更新日期：2011-04-01 00:00:00

abstract：:A study was undertaken to determine if the vascular characteristics measured by dynamic contrast-enhanced magnetic resonance imaging (primarily permeability surface area product and extracellular-extravascular tissue volume fraction) would be beneficial in explaining the inter-lesion metabolic heterogeneity displayed ...

journal_title：NMR in biomedicine

authors： Manton DJ,Lowry M,Rowland-Hill C,Crooks D,Mathew B,Turnbull LW

更新日期：2000-12-01 00:00:00

abstract：:The relaxation properties of water and metabolites were measured in rat brain following the occlusion of the middle cerebral artery (MCA) with localized 1H MRS. The PRESS sequence was employed to select volumes of 39 microL in the ischemic and the contralateral hemisphere. T1 and T2 relaxation times and peak intensiti...

journal_title：NMR in biomedicine

authors： van der Toorn A,Dijkhuizen RM,Tulleken CA,Nicolay K

更新日期：1995-09-01 00:00:00

abstract：:This paper compares two spectral processing methods for obtaining quantitative measures from in vivo prostate spectra, evaluates their effectiveness, and discusses the necessary modifications for accurate results. A frequency domain analysis (FDA) method based on peak integration was compared with a time domain fittin...

journal_title：NMR in biomedicine

authors： Pels P,Ozturk-Isik E,Swanson MG,Vanhamme L,Kurhanewicz J,Nelson SJ,Van Huffel S

更新日期：2006-04-01 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 measurements were performed on the N-acetyl aspartate (NAA) signal in in situ brains (in vivo and post-mortem) and on in vitro brain tissue at 37 degrees C using wide ranges of b-values (from 0 up to 4.5 x 10(6) s/cm2 and 35.8 x 10(6) s/cm2 for the in vivo and the in vitro cases, respectively). In vivo and i...

journal_title：NMR in biomedicine

authors： Assaf Y,Cohen Y

更新日期：1998-04-01 00:00:00

abstract：:A novel and fast time-domain quantitation algorithm--quantitation based on semi-parametric quantum estimation (QUEST)--invoking optimal prior knowledge is proposed and tested. This nonlinear least-squares algorithm fits a time-domain model function, made up from a basis set of quantum-mechanically simulated whole-meta...

journal_title：NMR in biomedicine

authors： Ratiney H,Sdika M,Coenradie Y,Cavassila S,van Ormondt D,Graveron-Demilly D

更新日期：2005-02-01 00:00:00

abstract：:The purpose of this study was to investigate the reliability of 3D isotropic MRI and quantitative multi-parametric MRI characterization on an orthotopic pancreatic head tumor model in rats. 3D isotropic T2 -weighted MRI was performed as a routine for tumor longitudinal follow-up and volume estimation. Common bile duct...

journal_title：NMR in biomedicine

authors： Yin T,Peeters R,Feng Y,Liu Y,Yu J,Dymarkowski S,Himmelreich U,Oyen R,Ni Y

更新日期：2017-02-01 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

authors： Kale SC,Chen XJ,Henkelman RM

更新日期：2009-06-01 00:00:00

abstract：:Exercise studies investigating the metabolic response of calf muscles using 31 P MRS are usually performed with a single knee angle. However, during natural movement, the distribution of workload between the main contributors to force, gastrocnemius and soleus is influenced by the knee angle. Hence, it is of interest ...

journal_title：NMR in biomedicine

authors： Niess F,Fiedler GB,Schmid AI,Laistler E,Frass-Kriegl R,Wolzt M,Moser E,Meyerspeer M

更新日期：2018-06-01 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

authors： Borga M,Thomas EL,Romu T,Rosander J,Fitzpatrick J,Dahlqvist Leinhard O,Bell JD

更新日期：2015-12-01 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