392 results on '"Magnetic resonance study"'
Search Results
52. Diagnostic accuracy of diffusion tensor imaging in differentiating malignant from benign compressed vertebrae
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Fatma Mohamed Sherif and Ahmed Abdel Khalek Abdel Razek
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Adult ,Male ,Diagnostic accuracy ,030218 nuclear medicine & medical imaging ,Diagnosis, Differential ,03 medical and health sciences ,0302 clinical medicine ,Fractional anisotropy ,Magnetic resonance study ,Medicine ,Humans ,Radiology, Nuclear Medicine and imaging ,Neuroradiology ,Aged ,Spinal Neoplasms ,business.industry ,Middle Aged ,Mr imaging ,Diffusion Tensor Imaging ,Anisotropy ,Female ,Spinal Diseases ,Neurology (clinical) ,Cardiology and Cardiovascular Medicine ,business ,Nuclear medicine ,030217 neurology & neurosurgery ,Diffusion MRI - Abstract
To study diagnostic accuracy of diffusion tensor imaging (DTI) in differentiating malignant from benign compressed vertebrae. This study was done on 43 patients with compressed vertebrae on conventional magnetic resonance study that underwent DTI. The mean diffusivity (MD) and fractional anisotropy (FA) of malignant (n = 24) and benign (n = 19) compressed vertebrae were calculated by two readers. There was a significantly lower (P = 0.001) MD of both readers between malignant (0.74 ± 0.2 and 0.78 ± 0.2 × 10−3 mm2/s) and benign (1.67 + 0.3 and 1.63 ± 0.3 × 10−3 mm2/s) compressed vertebrae. The FA of malignant compressed vertebrae of both readers (0.55 ± 0.2 and 0.52 ± 0.1) was significantly higher (P = 0.001) than that of benign (0.26 ± 0.1 and 0.28 ± 0.1) compressed vertebrae. There was excellent inter-reader agreement between both readers using MD (K = 0.91) and FA (K = 0.86). The thresholds of MD and FA used for differentiating malignant from benign compressed vertebrae of both readers were 1.15 and 1.16 × 10−3 mm2/s and 0.37 and 0.34 with area under the curve (AUC) of 0.98, 0.96, 0.93, and 0.92 and diagnostic accuracy of 95.3%, 88.4%, 90.1%, and 86.0% respectively. Combined MD and FA revealed AUC of 0.99 and 0.97 and diagnostic accuracy of 95.3% and 93.0% by both readers respectively. DTI is a non-invasive technique providing accurate imaging parameters that can be used for differentiating malignant from benign compressed vertebrae.
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- 2019
53. Aortic regurgitation is common in hypertrophic cardiomyopathy: An echocardiography and cardiovascular magnetic resonance study
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Yong Jiang, Minjie Lu, Andrew E. Arai, Jun-Qiang Lei, Sirajuddin Arlene, Gang Yin, Shihua Zhao, Chen Cui, Zheng Zhang, Weichun Wu, Zixian Chen, and Shunlin Guo
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Male ,medicine.medical_specialty ,Heart Ventricles ,Aortic Valve Insufficiency ,macromolecular substances ,Regurgitation (circulation) ,030218 nuclear medicine & medical imaging ,Ventricular Outflow Obstruction ,03 medical and health sciences ,0302 clinical medicine ,Internal medicine ,medicine ,Magnetic resonance study ,Humans ,Radiology, Nuclear Medicine and imaging ,In patient ,cardiovascular diseases ,Interventricular septum ,Retrospective Studies ,medicine.diagnostic_test ,business.industry ,Hypertrophic cardiomyopathy ,Magnetic resonance imaging ,General Medicine ,Cardiomyopathy, Hypertrophic ,Middle Aged ,medicine.disease ,Comorbidity ,Magnetic Resonance Imaging ,medicine.anatomical_structure ,Echocardiography ,030220 oncology & carcinogenesis ,Aortic Valve ,cardiovascular system ,Cardiology ,Female ,Cardiac magnetic resonance ,business - Abstract
To investigate the incidence, mechanism, and risk factors of aortic regurgitation (AR) in patients with hypertrophic cardiomyopathy (HCM) by using echocardiography and cardiac magnetic resonance (CMR).105 HCM patients, 52 hypertension (HTN) patients and 50 healthy controls (HC) were retrospectively recruited. HCM patients were divided into 38 with AR (HCMAR) subject and 67 without AR. The subaortic complex, D1 (the largest distance of the interventricular septum that protruded into the LVOT) and D3 (the LVOT effective width) were assessed and compared between the two groups of HCM patients.AR was more common in HCM than in HTN and HC (36 %, 17 %, and 10 %, respectively, P = 0.001). HCM patients with AR were older (58 ± 11 vs. 45 ± 16 years, P0.001) and had a higher incidence of hypertension (55 % vs. 33 %, P = 0.03). D1 was greater (13.5 ± 4.4 vs. 10.6 ± 4.0 mm, P = 0.001), and D3 was shorter in the HCMAR group (10.2 ± 5.3 vs. 13.7 ± 5.9 mm, P = 0.003). Anterior mitral leaflet length and left atrial diameter were greater in HCMAR group (all P0.05). On multivariable logistic regression analysis, the independent risk factors of AR in HCM patients were LVOTO and age.This study demonstrated that AR is a common comorbidity of HCM, especially in patients with LVOTO. LVOTO and age were independent risk factors of AR in HCM patient.
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- 2019
54. Cerebrovascular Lesions in Mixed Neurodegenerative Dementia: A Neuropathological and Magnetic Resonance Study
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Didier Leys, Claude-Alain Maurage, Vincent Deramecourt, Régis Bordet, Florent Auger, Florence Pasquier, Nicolas Durieux, Jacques De Reuck, and Charlotte Cordonnier
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Lewy Body Disease ,Male ,0301 basic medicine ,Pathology ,medicine.medical_specialty ,Mri studies ,03 medical and health sciences ,0302 clinical medicine ,Alzheimer Disease ,mental disorders ,Magnetic resonance study ,Humans ,Medicine ,Aged ,Cerebrovascular pathology ,Aged, 80 and over ,business.industry ,Brain ,Middle Aged ,medicine.disease ,Magnetic Resonance Imaging ,nervous system diseases ,Cerebrovascular Disorders ,030104 developmental biology ,Neurology ,Mixed dementia ,Dementia ,Female ,Neurology (clinical) ,Lewy body pathology ,Cerebral amyloid angiopathy ,Neurodegenerative dementia ,business ,Lewy body disease ,030217 neurology & neurosurgery - Abstract
Background: In elderly brains of demented patients, Alzheimer and Lewy body pathology (LBP) are frequently associated. Cortical microinfarcts (CoMIs) are more observed in Lewy body disease, even in the absence of cerebral amyloid angiopathy (CAA). The present neuropathological and 7.0-tesla MRI studies investigate whether CoMIs are also more frequent in mixed neurodegenerative dementia syndromes. Summary: Both examinations revealed that CoMIs are increased to different degrees in mixed dementia syndromes according to the severity of the LBP. They were mainly associated with a trend of older age and arterial hypertension in the patients with the most severe LBP. Messages: The increased number of CoMIs in mixed dementia syndromes with LBP is mainly due to the associated cerebrovascular pathology, even in the absence of CAA.
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- 2017
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55. Magnetic Resonance Study of the Spin-1/2 Quantum Magnet BaAg2Cu[VO4]2
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Angela Möller, Anja U. B. Wolter, Bernd Büchner, Hans-Joachim Grafe, Yulia Krupskaya, Markus Schäpers, Evgeniya Vavilova, and Vladislav Kataev
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Materials science ,Condensed matter physics ,02 engineering and technology ,021001 nanoscience & nanotechnology ,01 natural sciences ,Spin chain ,Magnet ,0103 physical sciences ,Magnetic resonance study ,Physical and Theoretical Chemistry ,010306 general physics ,0210 nano-technology ,Quantum ,Spin-½ - Abstract
BaAg2Cu[VO4]2 contains Cu(II) S=1/2 ions on a distorted two-dimensional triangular lattice interconnected via non-magnetic [VO4] entities. DFT band structure calculations, quantum Monte-Carlo simulations, and high-field magnetization measurements show that the magnetism of this compound is determined by a superposition of ferromagnetic (FM) and antiferromagnetic (AFM) uniform spin-1/2 chains with nearest neighbor exchange couplings of J FM=−19 K and J AFM=9.5 K (A. Tsirlin, A. Möller, B. Lorenz, Y. Skourski, H. Rosner, Phys. Rev. B 85 (2012) 014401). Here we report the study of BaAg2Cu[VO4]2 by high-field/frequency electron spin resonance (HF-ESR) and nuclear magnetic resonance (NMR) spectroscopies, which probe the local magnetic properties. In the HF-ESR measurements, we observe an anisotropic ESR spectrum typical for the Cu(II) ions and determine the g-tensor, g ||=2.38 and g ⊥=2.06. Moreover, we see a substantial change in the spectral shape of the ESR lines at low temperatures indicating the presence of short range magnetic correlations. The analysis of the low-temperature ESR spectra shows that its peculiar structure is due to the development of the anisotropic internal fields corresponding to FM and AFM correlations in the respective Cu spin chains. In the NMR spectra the signals from 51V nuclei in the two types of chains were identified. The analysis of the temperature evolution of these signals strongly supports the ESR findings on the occurrence of two types of Cu chains. Altogether, the HF-ESR and NMR results confirm theoretical predictions of the superposition of FM and AFM Cu(II) spin-1/2 chains in the studied material.
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- 2016
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56. Magnetic Resonance Study of p‐Type 3C SiC Microparticles
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Dariya Savchenko, Ján Lančok, Ekaterina N. Kalabukhova, Evgeniy Ubyivovk, Volodymyr O. Yukhymchuk, Evgenii Mokhov, M.A. Skoryk, and Bela Shanina
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Nuclear magnetic resonance ,Materials science ,chemistry ,law ,Jahn–Teller effect ,Magnetic resonance study ,chemistry.chemical_element ,Condensed Matter Physics ,Electron paramagnetic resonance ,Boron ,Electronic, Optical and Magnetic Materials ,law.invention - Published
- 2020
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57. Splenic Blood Flow Increases after Hypothermic Stimulus (Cold Pressor Test): A Perfusion Magnetic Resonance Study
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Cristian Borrazzo, Carlo Catalano, Angelica Bracci, Edoardo Rosato, Giulia Cundari, Giacomo Pambianchi, Nicola Galea, Iacopo Carbone, and Marco Francone
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Adult ,Male ,Article Subject ,Gadolinium ,Heart Ventricles ,splenic blood flow ,lcsh:Medicine ,chemistry.chemical_element ,Hemodynamics ,030204 cardiovascular system & hematology ,perfusion ,General Biochemistry, Genetics and Molecular Biology ,030218 nuclear medicine & medical imaging ,magnetic resonance ,03 medical and health sciences ,0302 clinical medicine ,Hypothermia, Induced ,Magnetic resonance study ,Medicine ,Humans ,General Immunology and Microbiology ,business.industry ,Myocardium ,lcsh:R ,Cold pressor test ,Myocardial Perfusion Imaging ,cold pressor test ,General Medicine ,Blood flow ,Hypothermia ,Middle Aged ,Cold Temperature ,Autonomic nervous system ,chemistry ,Regional Blood Flow ,Female ,medicine.symptom ,business ,Nuclear medicine ,Perfusion ,Magnetic Resonance Angiography ,Spleen ,Research Article - Abstract
The Cold Pressor Test (CPT) is a novel diagnostic strategy to noninvasively assess the myocardial microvascular endothelial-dependent function using perfusion magnetic resonance imaging (MRI). Spleen perfusion is modulated by a complex combination of several mechanisms involving the autonomic nervous system and vasoactive mediators release. In this context, the effects of cold temperature on splenic blood flow (SBF) still need to be clarified. Ten healthy subjects were studied by MRI. MRI protocol included the acquisition of GRE T1-weighted sequence (“first pass perfusion”) during gadolinium administration (0.1mmol/kg of Gd-DOTA at flow of 3.0 ml/s), at rest and after CPT. Myocardial blood flow (MBF) and SBF were measured by applying Fermi function deconvolution, using the blood pool input function sampled from the left ventricle cavity. MBF and SBF values after performing CPT were significantly higher than rest values (SBF at rest: 0.65 ± 0.15 ml/min/g Vs. SBF after CPT: 0.90 ± 0.14 ml/min/g, p
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- 2019
58. Optically detected magnetic resonance study of relaxation/emission processes in the nanoparticle-polymer composite
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G. Yu. Rudko, A. E. Raevskaya, A. O. Kovalchuk, Oleksandr Stroyuk, Jan Eric Stehr, V. I. Fediv, Weimin Chen, Volodymyr Dzhagan, Igor Vorona, and Irina Buyanova
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Solid-state chemistry ,Photoluminescence ,Materials science ,CdS nanoparticles ,optically detected magnetic resonance ,polymer ,Nanoparticle ,Materialkemi ,02 engineering and technology ,01 natural sciences ,composites ,0103 physical sciences ,Magnetic resonance study ,Materials Chemistry ,Electrical and Electronic Engineering ,010302 applied physics ,Nanocomposite ,Relaxation (NMR) ,Polymeric matrix ,021001 nanoscience & nanotechnology ,cds nanoparticles ,Atomic and Molecular Physics, and Optics ,lcsh:QC1-999 ,Electronic, Optical and Magnetic Materials ,Chemical engineering ,Polymer composites ,photoluminescence ,0210 nano-technology ,lcsh:Physics - Abstract
Two nanocomposites containing CdS nanoparticles in polymeric matrices were studied using the photoluminescence (PL) and optically detected magnetic resonance (ODMR) methods. Due to equal sizes of NPs in the composites (~5 nm) but different matrices – the oxygen-containing polymer PVA (polyvinyl alcohol) and oxygen-free polymer PEI (polyethyleneimine) – differences of nanocomposites properties are predominantly caused by different interfacial conditions. ODMR spectra have revealed five types of centers related to the PL emission – four centers involved in radiative recombination and one center related to non-radiative recombination processes. The oxygen-related interfacial center in CdS/PVA (LK1-center) and sulfur vacancy center in CdS/PEI (Vs-center) were identified.
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- 2019
59. Genetic variants of HIF1α are associated with right ventricular fibrotic load in repaired tetralogy of Fallot patients: a cardiovascular magnetic resonance study
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Mark A. Fogel, A. J. Agopian, Elizabeth Goldmuntz, Sharon Edman, Thanh T. Hoang, Laura Mercer-Rosa, Michael D. Swartz, Paulo Henrique Manso, Laura E. Mitchell, and Anshuman Sewda
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Gadolinium DTPA ,Male ,lcsh:Diseases of the circulatory (Cardiovascular) system ,Contrast Media ,030218 nuclear medicine & medical imaging ,0302 clinical medicine ,Risk Factors ,Fibrosis ,Magnetic resonance study ,HIF1α ,Tetralogy of Fallot ,Ejection fraction ,Ventricular Remodeling ,Radiological and Ultrasound Technology ,medicine.diagnostic_test ,Right ventricular end-diastolic volume ,3. Good health ,Phenotype ,Treatment Outcome ,Cardiology ,Female ,medicine.symptom ,Cardiology and Cardiovascular Medicine ,medicine.medical_specialty ,Magnetic Resonance Imaging, Cine ,POLIMORFISMO ,Polymorphism, Single Nucleotide ,03 medical and health sciences ,Predictive Value of Tests ,Internal medicine ,medicine ,Humans ,Genetic Predisposition to Disease ,Radiology, Nuclear Medicine and imaging ,Cardiac Surgical Procedures ,Retrospective Studies ,Angiology ,Cardiovascular magnetic resonance imaging ,business.industry ,Research ,Infant, Newborn ,Genetic variants ,Infant ,Right ventricular ejection fraction ,Magnetic resonance imaging ,Hypoxia (medical) ,Hypoxia-Inducible Factor 1, alpha Subunit ,medicine.disease ,lcsh:RC666-701 ,Ventricular Function, Right ,business - Abstract
Background Studies suggest that right ventricular (RV) fibrosis is associated with RV remodeling and long-term outcomes in patients with tetralogy of Fallot (TOF). Pre-operative hypoxia may increase expression of hypoxia inducible factor-1-alpha (HIF1α) and promote transforming growth factor β1 (TGFβ1)-mediated fibrosis. We hypothesized that there would be associations between: (1) RV fibrosis and RV function, (2) HIF1α variants and RV fibrosis, and (3) HIF1α variants and RV function among post-surgical TOF cases. Methods We retrospectively measured post-surgical fibrotic load (indexed volume and fibrotic score) from 237 TOF cases who had existing cardiovascular magnetic resonance imaging using late gadolinium enhancement (LGE), and indicators of RV remodeling (i.e., ejection fraction [RVEF] and end-diastolic volume indexed [RVEDVI]). Genetic data were available in 125 cases. Analyses were conducted using multivariable linear mixed-effects regression with a random intercept and multivariable generalized Poisson regression with a random intercept. Results Indexed fibrotic volume and fibrotic score significantly decreased RVEF by 1.6% (p = 0.04) and 0.9% (p = 0.03), respectively. Indexed fibrotic volume and score were not associated with RVEDVI. After adjusting for multiple comparisons, 6 of the 48 HIF1α polymorphisms (representing two unique signals) were associated with fibrotic score. None of the HIF1α polymorphisms were associated with indexed fibrotic volume, RVEDVI, or RVEF. Conclusion The association of some HIF1α polymorphisms and fibrotic score suggests that HIF1α may modulate the fibrotic response in TOF. Electronic supplementary material The online version of this article (10.1186/s12968-019-0555-2) contains supplementary material, which is available to authorized users.
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- 2019
60. Can We Discriminate Symptomatic Hip Patients From Asymptomatic Volunteers Based on Anatomic Predictors? A 3-Dimensional Magnetic Resonance Study on Cam, Pincer, and Spinopelvic Parameters
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Lennart Jans, Reto Sutter, Paulo Rego, António Caetano, Pedro Dantas, Olufemi R. Ayeni, J Guimarães Consciência, Rui Mateus Marques, Vasco V. Mascarenhas, University of Zurich, and Mascarenhas, Vasco V
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Adult ,Male ,Volunteers ,medicine.medical_specialty ,Physical Therapy, Sports Therapy and Rehabilitation ,610 Medicine & health ,Asymptomatic ,030218 nuclear medicine & medical imaging ,Cohort Studies ,03 medical and health sciences ,0302 clinical medicine ,2732 Orthopedics and Sports Medicine ,Imaging, Three-Dimensional ,medicine ,Magnetic resonance study ,Femoracetabular Impingement ,Humans ,Orthopedics and Sports Medicine ,Femur ,3612 Physical Therapy, Sports Therapy and Rehabilitation ,Pelvic Bones ,Femoroacetabular impingement ,030222 orthopedics ,High prevalence ,business.industry ,Acetabulum ,Middle Aged ,medicine.disease ,Magnetic Resonance Imaging ,Spine ,Logistic Models ,ROC Curve ,Reference values ,Area Under Curve ,Case-Control Studies ,10046 Balgrist University Hospital, Swiss Spinal Cord Injury Center ,Female ,Hip Joint ,Radiology ,medicine.symptom ,business - Abstract
Background:Given the high prevalence of patients with hip deformities and no ongoing hip dysfunction, understanding the anatomic factors predicting the symptomatic state is critical. One such variable is how the spinopelvic parameters (SPPs) may interplay with hip anatomic factors.Hypothesis/Purpose:SPPs and femoral- and acetabular-specific parameters may predict which patients will become symptomatic. The purpose was to determine which anatomic characteristics with specific cutoffs were associated with hip symptom development and how these parameters relate to each other.Study Design:Cohort study (Diagnosis); Level of evidence, 2.Methods:548 participants were designated either symptomatic patients (n = 176, scheduled for surgery with hip pain and/or functional limitation) or asymptomatic volunteers (n = 372, no pain) and underwent 3-dimensional magnetic resonance imaging. Multiple femoral (α angle, Ω angle, neck angle, torsion), acetabular (version, coverage), and spinopelvic (pelvic tilt, sacral slope [SS], pelvic incidence) parameters were measured semiautomatically. Normative values, optimal differentiating thresholds, and a logistic regression analysis were computed.Results:Symptomatic patients had larger cam deformities (defined by increased Ω angle and α angle), smaller acetabular coverage, and larger pelvic incidence and SS angles compared with the asymptomatic volunteers. Discriminant receiver operating characteristic analysis confirmed that radial 2-o’clock α angle (threshold 58°-60°, sensitivity 75%-60%, specificity 80%-84%; area under the curve [AUC] = 0.831), Ω angle (threshold 43°, sensitivity 72%, specificity 70%; AUC = 0.830), acetabular inclination (threshold 6°, sensitivity 65%, specificity 70%; AUC = 0.709), and SS (threshold 44°, sensitivity 72%, specificity 75%; AUC = 0.801) ( P < .005) were the best parameters to classify participants. When parameters were entered into a logistic regression, significant positive predictors for the symptomatic patients were achieved for SS, acetabular inclination, Ω angle, and α angle at 2-o’clock, correctly classifying 85% of cases (model sensitivity 72%, specificity 91%; AUC = 0.919).Conclusion:Complex dynamic interplay exists between the hip and SPPs. A cam deformity, acetabular undercoverage, and increased SPP angles are predictive of a hip symptomatic state. SPPs were significant to discriminate between participants and were important in combination with other hip deformities. Symptomatic patients can be effectively differentiated from asymptomatic volunteers based on predictive anatomic factors.
- Published
- 2018
61. Incremental Value of Left Atrial Geometric Remodeling in Predicting Late Atrial Fibrillation Recurrence After Pulmonary Vein Isolation: A Cardiovascular Magnetic Resonance Study
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Warren J. Manning, Derin Tugal, Shiro Nakamori, Reza Nezafat, and Long Ngo
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Male ,medicine.medical_specialty ,Time Factors ,Magnetic Resonance Imaging (MRI) ,Magnetic Resonance Imaging, Cine ,030204 cardiovascular system & hematology ,Pulmonary Artery ,Pulmonary vein ,Imaging ,03 medical and health sciences ,cardiovascular magnetic resonance ,0302 clinical medicine ,Left atrial ,Predictive Value of Tests ,Recurrence ,Internal medicine ,Late Recurrence ,Atrial Fibrillation ,left atrial sphericity index ,Magnetic resonance study ,medicine ,late recurrence ,Humans ,030212 general & internal medicine ,Heart Atria ,Postoperative Period ,pulmonary vein isolation ,Original Research ,business.industry ,Atrial fibrillation ,Atrial Remodeling ,Middle Aged ,medicine.disease ,Increased risk ,Treatment Outcome ,Cardiology ,Catheter Ablation ,Atrial Function, Left ,Female ,Cardiology and Cardiovascular Medicine ,business ,left atrial volume ,Follow-Up Studies - Abstract
Background Left atrial ( LA ) enlargement is a marker for increased risk of atrial fibrillation ( AF ). However, LA remodeling is a complex process that is poorly understood, and LA geometric remodeling may also be associated with the development of AF . We sought to determine whether LA spherical remodeling or its temporal change predict late AF recurrence after pulmonary vein isolation ( PVI ). Methods and Results Two hundred twenty‐seven consecutive patients scheduled for their first PVI for paroxysmal or persistent AF who underwent cardiovascular magnetic resonance before and within 6 months after PVI were retrospectively identified. The LA sphericity index was computed as the ratio of the measured LA maximum volume to the volume of a sphere with maximum LA length diameter. During mean follow‐up of 25 months, 88 patients (39%) experienced late recurrence of AF . Multivariable Cox regression analyses identified an increased pre‐ PVI LA sphericity index as an independent predictor of late AF recurrence (hazard ratio, 1.32; 95% confidence interval, 1.07–1.62, P =0.009). Patients in the highest LA sphericity index tertile were at highest risk of late recurrence (highest versus lowest: 59% versus 28%; P LA sphericity index to the LA minimum volume index and passive emptying fraction provided important incremental prognostic information for predicting late AF recurrence post PVI (categorical net reclassification improvement, 0.43; 95% confidence interval, 0.16–0.69, P =0.001). Conclusions The assessment of pre‐ PVI LA geometric remodeling provides incremental prognostic information regarding late AF recurrence and may be useful to identify those for whom PVI has reduced success or for whom more aggressive ablation or medications may be useful.
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- 2018
62. Progressive left ventricular dysfunction and myocardial fibrosis in Duchenne and Becker muscular dystrophy: a longitudinal cardiovascular magnetic resonance study
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Kazuhiro Koyanagawa, Atsuhito Takeda, Noriko Oyama-Manabe, Yoichi M. Ito, Toshihisa Anzai, Hirokuni Yamazawa, Tadao Aikawa, and Masanao Naya
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Duchenne muscular dystrophy ,Male ,medicine.medical_specialty ,Adolescent ,Magnetic Resonance Imaging, Cine ,Angiotensin-Converting Enzyme Inhibitors ,030204 cardiovascular system & hematology ,Late gadolinium enhancement ,Ventricular Function, Left ,Mixed-effects model ,03 medical and health sciences ,Ventricular Dysfunction, Left ,Young Adult ,0302 clinical medicine ,Interquartile range ,Internal medicine ,medicine ,Magnetic resonance study ,Humans ,cardiovascular diseases ,Longitudinal Studies ,Muscular dystrophy ,Child ,Retrospective Studies ,Cardiovascular magnetic resonance imaging ,Ejection fraction ,medicine.diagnostic_test ,business.industry ,Myocardium ,Magnetic resonance imaging ,medicine.disease ,Fibrosis ,Confidence interval ,Muscular Dystrophy, Duchenne ,030228 respiratory system ,Becker muscular dystrophy ,Angiotensin-converting enzyme inhibitor ,Pediatrics, Perinatology and Child Health ,cardiovascular system ,Cardiology ,Disease Progression ,Myocardial fibrosis ,Female ,Cardiology and Cardiovascular Medicine ,business ,circulatory and respiratory physiology - Abstract
This study examined the progression of left ventricular dysfunction and myocardial fibrosis in patients with Duchenne muscular dystrophy (DMD) or Becker muscular dystrophy (BMD) to evaluate the effects of angiotensin-converting enzyme inhibitor (ACEI). Ninety-eight cardiovascular magnetic resonance (CMR) studies in 34 consecutive patients with DMD (n = 21) or BMD (n = 13) were retrospectively reviewed. Left ventricular ejection fraction (LVEF) and the extent of myocardial late gadolinium enhancement (LGE) were semiautomatically quantified. During the study period, five patients had already been treated with ACEI at the first CMR; five were started on ACEI at LVEF ≥ 55% and 10 at LVEF
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- 2018
63. Impact of the cone operation on left ventricular size, function, and dyssynchrony in Ebstein anomaly: a cardiovascular magnetic resonance study
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Jonathan Rhodes, David M. Harrild, Sitaram M. Emani, Andrew J. Powell, Abba Mejia-Spiegeler, Linyuan Jing, Brandon K. Fornwalt, and Rebecca S. Beroukhim
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Male ,lcsh:Diseases of the circulatory (Cardiovascular) system ,Time Factors ,030204 cardiovascular system & hematology ,Ventricular Function, Left ,030218 nuclear medicine & medical imaging ,Strain ,Ventricular Dysfunction, Left ,0302 clinical medicine ,Magnetic resonance study ,Child ,Ejection fraction ,Tricuspid valve ,Radiological and Ultrasound Technology ,medicine.diagnostic_test ,Left ventricular size ,Stroke volume ,medicine.anatomical_structure ,Treatment Outcome ,Child, Preschool ,Cardiology ,Female ,Tricuspid Valve ,Cardiology and Cardiovascular Medicine ,Adult ,medicine.medical_specialty ,Adolescent ,Heart Ventricles ,Magnetic Resonance Imaging, Cine ,03 medical and health sciences ,Young Adult ,Predictive Value of Tests ,Internal medicine ,Cone operation ,medicine ,Humans ,Radiology, Nuclear Medicine and imaging ,Ebstein anomaly ,Cardiac Surgical Procedures ,Angiology ,Retrospective Studies ,business.industry ,Research ,Magnetic resonance imaging ,Recovery of Function ,Myocardial Contraction ,Dyssynchrony ,EBSTEIN ANOMALY ,lcsh:RC666-701 ,Ventricular Function, Right ,Cardiovascular magnetic resonance ,business - Abstract
Background In addition to tricuspid regurgitation (TR) and right ventricular (RV) enlargement, patients with Ebstein anomaly are at risk for left ventricular (LV) dysfunction and dyssynchrony. We studied the impact of the cone tricuspid valve reconstruction operation on LV size, function, and dyssynchrony. Methods All Ebstein anomaly patients who had both pre- and postoperative cardiovascular magnetic resonance (CMR) studies were retrospectively identified. From cine images, RV and LV volumes and ejection fractions (EF) were calculated, and LV circumferential and longitudinal strain were measured by feature tracking. To quantify LV dyssynchrony, temporal offsets (TOs) were computed among segmental circumferential strain versus time curves using cross-correlation analysis and patient-specific reference curves. An LV dyssynchrony index was calculated as the standard deviation of the TOs. Results Twenty patients (65% female) were included with a median age at cone operation of 16 years, and a median time between pre- and postoperative CMR of 2.8 years. Postoperatively, there was a decline in the TR fraction (56 ± 19% vs. 5 ± 4%, p
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- 2018
64. A Magnetic Resonance Study and Demonstration of the Spectrum of Diverse Aetiologies for Trigeminal Neuralgia
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Seena Cheppala Rajan, Saveetha Veeraiyan, Adipudi Renuka, Aslam Malik, and Anita Soundarapandian
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microvascular decompression ,neurovascular compression ,business.industry ,Clinical Biochemistry ,lcsh:R ,lcsh:Medicine ,General Medicine ,medicine.disease ,Nuclear magnetic resonance ,Trigeminal neuralgia ,herpetic neuralgia ,Magnetic resonance study ,Medicine ,business ,trigeminal pontine sign - Abstract
Introduction: Intractable hemifacial pain or twitching can be an incapacitating disorder caused by trigeminal neuralgia. The aetiologies for trigeminal neuralgia are numerous and the most frequent cause is a neurovascular compression. However, there are other less common aetiologies which need to be assessed. Magnetic Resonance Imaging (MRI) with dedicated cranial nerve sequences remains the modality of choice in diagnosing and establishing a cause for this condition. Aim: This study aims in showing that all trigeminal neuralgias are not secondary to neurovascular compression and other unusual causes needs to be looked for and assessed during an MRI examination. Materials and Methods: This was a cross-sectional observational study conducted at the Saveetha Medical College and Hospital, Chennai, India (from September 2015 to August 2017). This study included 70 patients presenting with clinical symptoms of unilateral trigeminal neuralgia. The MRI was done using a 1.5 Tesla, Philips multiva system. A high resolution 3D T2 DRIVE or 3D bFFE cranial nerve sequences were performed in addition to the routine Magnetic Resonance (MR) sequences. Patients with known dental issues which could cause the pain, and patients with intracranial tumours were excluded from the study. Results: Out of the 70 patients, we found that the majority (53) had a neurovascular compression, which ranged from a simple indentation by a tortuous Superior Cerebellar Artery (SCA) to full blown vertebrobasilar dolichoectasia. Out of the remaining cases, six were found to be secondary to benign intracranial hypertension with prominent Meckel’s caves. There were two cases who had an unusual finding of “Trigeminal pontine sign”, which were post infective (postherpetic being the most probable cause). Conclusion: By tailoring the MRI protocol in present study, and based on the clinical presentation, we can conclude that in most cases of clinically diagnosed trigeminal neuralgia, it could be possible to demonstrate a probable cause and consequently aid the clinician for appropriate management, and to select only the deserving cases for microvascular decompression.
- Published
- 2018
65. Functional Magnetic Resonance Study of Non-conventional Morphological Brains: malnourished rats
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Richard L. Martin, R. Godinez, F. Vazquez, O. Marrufo, Alfredo O. Rodriguez, and S. E. Solis-Najera
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Brain activation ,Trigeminal nerve ,medicine.diagnostic_test ,fmri ,Biomedical Engineering ,food and beverages ,Magnetic resonance imaging ,malnutrition ,Biology ,magnetic resonance ,birdcage coil ,Nuclear magnetic resonance ,nervous system ,Control and Systems Engineering ,brain activation ,QA1-939 ,medicine ,Magnetic resonance study ,trigeminal nerve ,Instrumentation ,Birdcage coil ,Mathematics - Abstract
Malnutrition during brain development can cause serious problems that can be irreversible. Dysfunctional patterns of brain activity can be detected with functional MRI. We used BOLD functional Magnetic Resonance Imaging (fMRI) to investigate region differences of brain activity between control and malnourished rats. The food-competition method was applied to a rat model to induce malnutrition during lactation. A 7T magnet was used to detect changes of the BOLD signal associated with changes in brain activity caused by the trigeminal nerve stimulation in malnourished and control rats. Major neuronal activation was observed in malnourished rats in several brain regions, including cerebellum, somatosensory cortex, hippocampus, and hypothalamus. Statistical analysis of the BOLD signals from various brain areas revealed significant differences in somatosensory cortex between the control and experimental groups, as well as a significant difference between the cerebellum and other structures in the experimental group. This study, particularly in malnourished rats, demonstrates increased BOLD activation in the cerebellum.
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- 2015
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66. Magnetic resonance study of co-modified (Co,N)-TiO2 nanocomposites
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Grzegorz Zolnierkiewicz, Antoni W. Morawski, Janusz Typek, Niko Guskos, Aleksander Guskos, D. Dolat, Paweł Berczyński, C. J. Aidinis, and Sylwia Mozia
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Nuclear and High Energy Physics ,Nanocomposite ,titanium dioxide ,Science ,Condensed Matter Physics ,Ferromagnetic resonance ,Condensed Matter::Materials Science ,chemistry.chemical_compound ,ferromagnetic resonance ,Nuclear Energy and Engineering ,Chemical engineering ,chemistry ,nanocomposites ,Titanium dioxide ,Magnetic resonance study ,Condensed Matter::Strongly Correlated Electrons ,Safety, Risk, Reliability and Quality ,Waste Management and Disposal ,Instrumentation - Abstract
Three nCo,N-TiO2 nanocomposites (where cobalt concentration index n = 1, 5 and 10 wt %) were prepared and investigated by magnetic resonance spectroscopy at room temperature. Ferromagnetic resonance (FMR) lines of magnetic cobalt agglomerated nanoparticle were dominant in all registered spectra. The relaxation processes and magnetic anisotropy of the investigated spin system essentially depended on the concentration of cobalt ions. It is suggested that the samples contained two magnetic types of sublattices forming a strongly correlated spin system. It is suggested that the existence of strongly correlated magnetic system has an essential influence of the photocatalytic properties of the studied nanocomposites.
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- 2015
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67. A multinuclear magnetic resonance study of fluoro derivatives of hydroxybenzaldehydes
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Rosa M. Claramunt, Carla I. Nieto, José Elguero, Dionisia Sanz, and Ibon Alkorta
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Chemistry ,Magnetic resonance study ,General Materials Science ,General Chemistry ,Medicinal chemistry - Abstract
This work has been supported by the Spanish Ministerio de Ciencia e Innovacion (CTQ2010-16122), the Ministerio de Economia y Competitividad (CTQ2012-35513-C02-02, CTQ2014-56833-R), and the Comunidad Autonoma de Madrid (S2013/MIT-2841, Fotocarbon). Computer, storage, and other resources from the CTI (CSIC) are gratefully acknowledged. One of us (C. I. Nieto) is indebted to UNED for a predoctoral fellowship (FPI ‘Grupos de Investigacion’ UNED).
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- 2015
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68. Nuclear Science
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Shafer, Wade H. and Shafer, Wade H., editor
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- 1994
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69. Safety of dorsal wrist arthroscopy portals: A magnetic resonance study
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Luigi Cazzato, Umile Giuseppe Longo, Riccardo Del Vescovo, Vincenzo Denaro, Mattia Loppini, Bruno Beomonte Zobel, and Nicola Maffulli
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Adult ,Male ,Wrist Joint ,01 natural sciences ,030218 nuclear medicine & medical imaging ,010104 statistics & probability ,03 medical and health sciences ,Arthroscopy ,0302 clinical medicine ,Dorsal portals ,Dorsal ulnar nerve ,Radial vascular bundle ,Superficial radial nerve ,Ulnar vascular bundle ,Wrist arthroscopy ,Surgery ,Peripheral Nerve Injuries ,medicine ,Magnetic resonance study ,Humans ,0101 mathematics ,Ulnar nerve ,Radial nerve ,medicine.diagnostic_test ,business.industry ,Magnetic resonance imaging ,Anatomy ,Neurovascular bundle ,Magnetic Resonance Imaging ,Female ,Dorsal wrist ,business - Abstract
In wrist arthroscopy, the standard dorsal portals are the most commonly used. However, their placement can be associated with injuries to the neurovascular structures of the radiocarpal joint. The present study assessed and compared the distance of commonly used dorsal portals to radial and ulnar neurovascular structures. Forty patients (20 males, 20 females) were evaluated with T1-weighted spin-echo (SE) magnetic resonance (MR) sequences. We measured the distance between 1-2 and 3-4 portals and radial vascular bundle and the nearest branch of the superficial branch of radial nerve (SBRN). We also measured the distance between 4 and 5, 6/U and 6/R and ulnar vascular bundle and the nearest branch of the dorsal ulnar nerve (DUN). The median age of patients was 39 years (95% IC 36.97-43.32 years). The 3-4 portal was farther away from the vascular structure than the 1-2 portal (P 0.0001), 4-5 portal (P = 0.008), 6/R (P 0.0001), and 6/U portals (P 0.0001). Moreover, the 3-4 portal was farther away from the nerve branch than the 1-2 portal (P 0.0001), 4-5 portal (P 0.0001), 6/R (P 0.0001), and 6/U portals (P 0.0001). No statistical significant differences were found between the two genders. The 3-4 and 4-5 portals are the farthest away from the neurovascular structures, and likely reduce the risk to damage these structures. On the other hand, the 1-2 and 6/U portals likely increase the risk of neurovascular damage, because of their proximity to neurovascular structures.Diagnostic study; Level III.
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- 2018
70. Physical Principles of Magnetic Resonance and Magnetic Resonance Angiography
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Fridon Todua and Dudana Gachechiladze
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Materials science ,Nuclear magnetic resonance ,medicine.diagnostic_test ,media_common.quotation_subject ,medicine ,Magnetic resonance study ,Contrast (vision) ,Magnetic resonance imaging ,Magnetic resonance angiography ,media_common - Abstract
In 1950–1960 nuclear magnetic resonance was the most acceptable method of study of configuration of chemical structure of substances and reactive processes. In 1973 Lauterbach performed the first magnetic resonance study. Since 1983, the development of magnetic resonance equipment and its software later gave a possibility to the investigators to receive a high contrast image of 1 mm slice within several seconds.
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- 2018
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71. Effects of Catching Method, Rigor Status at Processing, and Pre-salting Methods on the Water Distribution and Characteristics of Heavily Salted Atlantic Cod (Gadus morhua) Muscle: A Multi-parametric Magnetic Resonance Study
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Ásbjörn Jónsson, Magnea G. Karlsdóttir, Amidou Traore, Sigurjón Arason, María Gudjónsdóttir, Faculty of Food Science and Nutrition, University of Iceland, Qualité des Produits Animaux (QuaPA), Institut National de la Recherche Agronomique (INRA), Value Chain, Processing and Aquaculture, and Matis Ohf Food Safety Environm & Genet
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imagerie par résonance magnétique ,heavily salted cod (bacalao) ,Multi parametric ,biology ,Chemistry ,Physicochemical properties ,[SDV]Life Sciences [q-bio] ,résonance magnétique nucléaire ,Salting ,salting method ,rigor status ,catching method ,biology.organism_classification ,NMR ,salting ,Fishery ,nuclear magnetic resonance ,Oceanography ,salage ,propriété physicochimique ,Magnetic resonance study ,Gadus ,Atlantic cod ,capture ,MRI - Abstract
The distribution and characteristics of water in the muscle of various commercially available Icelandic heavily salted Atlantic cod products were analyzed with proton magnetic resonance methods. The products varied in choice of catching method, in pre- or post-rigor processing, flattening or filleting cut, and pre-salting technique (brine injection with salt with/without polyphosphates, brining and pickling) and choice of brine-injection instruments.All products had heterogeneous water distributions, but the level of heterogeneity was dependent on the handling during processing. Brine injection led to salt-induced swelling, which effect remained after the kench dry salting step. Double brine injection induced needle traces in the muscle, even after kench salting. Relaxation time analysis indicated that pickle salted products had the highest degree of protein denaturation in the muscle amongst the analyzed pre-salting methods. The multi-parametric analysis indicated how powerful the MR methods are for process and product characterization and optimization.
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- 2018
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72. P4502Risk factors for the development of heart failure in hypertrophic cardiomyopathy: a cardiovascular magnetic resonance study
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E. Di Pietro, Dudley J. Pennell, Rory O'Hanlon, Vieira, Gajen Kanaganayagam, B. Wong, S Prasad, Frances M. Mitchell, Alphonsus C. Liew, A. Ali, Claire E. Raphael, Vassilis Vassiliou, K. Sun, and Simon Newsome
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medicine.medical_specialty ,business.industry ,Internal medicine ,Heart failure ,Hypertrophic cardiomyopathy ,medicine ,Magnetic resonance study ,Cardiology ,Cardiology and Cardiovascular Medicine ,medicine.disease ,business - Published
- 2017
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73. Paramagnetic Ce3+ optical emitters in garnets: Optically detected magnetic resonance study and evidence of Gd-Ce cross-relaxation effects
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N. G. Romanov, Herfried Wieczorek, Pavel G. Baranov, A. G. Badalyan, D. O. Tolmachev, A. G. Petrosyan, A. S. Gurin, G. R. Asatryan, C. Ronda, and Yu. A. Uspenskaya
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Paramagnetism ,Materials science ,Nuclear magnetic resonance ,0103 physical sciences ,Magnetic resonance study ,02 engineering and technology ,021001 nanoscience & nanotechnology ,010306 general physics ,0210 nano-technology ,01 natural sciences ,Cross relaxation - Published
- 2017
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74. Vinylsilylferrocenes and Ethynyl(vinyl)silylferrocenes. Synthesis, Multinuclear Magnetic Resonance Study and DFT Calculations
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Elena V. Klimkina and Bernd Wrackmeyer
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Coupling constant ,Chemistry ,Magnetic resonance study ,General Chemistry ,Photochemistry - Abstract
Ferrocenylsilanes with various functions at silicon (chlorine, vinyl, ethynyl) were prepared and studied by multinuclear magnetic resonance methods (1H, 13C, 29Si NMR spectroscopy). The gasphase geometries of the silanes were optimized by calculations at the B3LYP=6-311+G(d,p) level of theory, and NMR parameters (chemical shifts δ13C, δ29Si, spin-spin coupling constants) were calculated at the same level of theory.
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- 2014
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75. Anatomy of the zona orbicularis of the hip: a magnetic resonance study
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Richard E. Field, Francesc Malagelada, Giles H. Stafford, Samuel J. Barke, and Rene Tayar
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Adult ,Male ,medicine.medical_specialty ,Adolescent ,Pathology and Forensic Medicine ,Young Adult ,Synovial folds ,Femoral head ,medicine ,Magnetic resonance study ,Humans ,Synovial fluid ,Radiology, Nuclear Medicine and imaging ,Aged ,Retrospective Studies ,Femoral neck ,medicine.diagnostic_test ,business.industry ,Magnetic resonance imaging ,Anatomy ,Middle Aged ,Magnetic Resonance Imaging ,medicine.anatomical_structure ,Zona orbicularis ,Orthopedic surgery ,Female ,Hip Joint ,Surgery ,business - Abstract
This study aimed at describing the anatomy of the zona orbicularis (ZO), based on magnetic resonance arthrography (MRA) and magnetic resonance imaging (MRI) scans and to assess the presence of synovial folds in relation to the ZO. A retrospective review was performed using consecutive hip and pelvic MRA and MRI examinations from our institution. We identified 25 normal scans of each variety. Patients were scanned in a neutral hip position and 3D FIESTA sequence images were included in a number of cases. Using electronic callipers, measurements were obtained of the ZO thickness and of the location of the ZO with respect of the femoral head and neck. On MRA, the ZO appeared as a horseshoe in 18/25 patients, being absent anteriorly. On MRI the ZO was less consistent and absent in 12/25 posteriorly, in 8/25 inferiorly and in 2/25 anteriorly. Where present, the ZO usually coincided with the boundary of femoral head sphericity and the narrowest point of the isthmus of the femoral neck. The medial synovial fold was identified in all MRA studies (25/25). The ZO of the hip is most consistently identified when the joint is distended and in approximately 75 % of cases appears as a horseshoe-shaped structure. Superiorly, the ZO is aligned perpendicular to the long axis of the femoral neck. The ZO twists from postero-lateral to antero-medial as it moves inferiorly. Our findings are consistent with the hypothesis that the ZO functions as a ring that resists femoral head distraction and contributes to dynamic circulation of synovial fluid.
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- 2014
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76. Revisiting the End-Diastolic Forward Flow (Restrictive Physiology) in Tetralogy of Fallot
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Jack Rychik, Laura Mercer-Rosa, Stephen M. Paridon, Elizabeth Goldmuntz, Wei Yang, and Mark A. Fogel
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0301 basic medicine ,Contraction (grammar) ,business.industry ,Diastole ,Physiology ,macromolecular substances ,Forward flow ,030204 cardiovascular system & hematology ,medicine.disease ,Main Pulmonary Artery ,03 medical and health sciences ,030104 developmental biology ,0302 clinical medicine ,cardiovascular system ,Magnetic resonance study ,Medicine ,Radiology, Nuclear Medicine and imaging ,In patient ,cardiovascular diseases ,Cardiology and Cardiovascular Medicine ,business ,Tetralogy of Fallot - Abstract
Antegrade end-diastolic flow in the main pulmonary artery with atrial contraction (ADF) is observed in patients with repaired tetralogy of Fallot (TOF) and is thought to represent restrictive right ventricular (RV) physiology. We sought to investigate the association of ADF with pulmonary
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- 2018
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77. Magnetic resonance study of lightly boron-doped diamond
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N. Froumin, Alexander M. Panich, Alexander I. Shames, Shaul D. Goren, and Olga Shenderova
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Biomaterials ,Boron doped diamond ,Materials science ,Polymers and Plastics ,law ,Metals and Alloys ,Analytical chemistry ,Magnetic resonance study ,Electron paramagnetic resonance ,Surfaces, Coatings and Films ,Electronic, Optical and Magnetic Materials ,law.invention - Published
- 2019
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78. Effects of gaze direction, head orientation and valence of facial expression on amygdala activity
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Andreas Sauer, Thomas Straube, Wolfgang H. R. Miltner, and Martin Mothes-Lasch
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Male ,Dorsum ,Cognitive Neuroscience ,media_common.quotation_subject ,Emotions ,Experimental and Cognitive Psychology ,Fixation, Ocular ,Neuropsychological Tests ,Amygdala ,Young Adult ,Orientation ,Perception ,medicine ,Magnetic resonance study ,Humans ,Attention ,Valence (psychology) ,media_common ,Facial expression ,Original Articles ,General Medicine ,Stimulus Ambiguity ,Magnetic Resonance Imaging ,Gaze ,Facial Expression ,medicine.anatomical_structure ,Pattern Recognition, Visual ,Social Perception ,Female ,Psychology ,Neuroscience ,Photic Stimulation ,Cognitive psychology - Abstract
There is increasing evidence for a role of the amygdala in processing gaze direction and emotional relevance of faces. In this event-related functional magnetic resonance study we investigated amygdala responses while we orthogonally manipulated head direction, gaze direction and facial expression (angry, happy and neutral). This allowed us to investigate effects of stimulus ambiguity, low-level factors and non-emotional factors on amygdala activation. Averted vs direct gaze induced increased activation in the right dorsal amygdala regardless of facial expression and head orientation. Furthermore, valence effects were found in the ventral amygdala and strongly dependent on head orientation. We observed enhanced activation to angry and neutral vs happy faces for observer-directed faces in the left ventral amygdala while the averted head condition reversed this pattern resulting in increased activation to happy as compared to angry and neutral faces. These results suggest that gaze direction drives specifically dorsal amygdala activation regardless of facial expression, low-level perceptual factors or stimulus ambiguity. The role of the amygdala is thus not restricted to the detection of potential threat, but has a more general role in attention processes. Furthermore, valence effects are associated with activation of the ventral amygdala and strongly influenced by non-emotional factors.
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- 2013
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79. Magnetic Resonance Study of a PbWO4:Ce Single Crystal Doped with Ce Paramagnetic Ions
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Tae Ho Yeom and Ae Ran Lim
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Paramagnetism ,Materials science ,Condensed matter physics ,Doping ,Magnetic resonance study ,Spin–lattice relaxation ,General Physics and Astronomy ,Single crystal ,Ion - Published
- 2013
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80. Magnetic Resonance Studies of Graphite Lamellar Compounds
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Lauginie, P., Conard, J., Estrada, H., Guerard, D., El Makhini, M., Lagrance, P., Fuzelier, M., Furdin, G., Vasse, R., Fraissard, Jacques P., editor, and Resing, Henry A., editor
- Published
- 1980
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81. Kinetic and Magnetic Resonance Studies on Amine Oxidases
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Knowles, P. F., Lowe, D. J., Peters, J., Thorneley, R. N. F., Yadav, K. D. S., Bertini, I., editor, Drago, R. S., editor, and Luchinat, C., editor
- Published
- 1983
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82. A Magnetic Resonance Study of Native and Modified Illinois Coal
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Duliba, Edward P., Clarkson, R. B., Petrakis, Leonidas, editor, and Fraissard, Jacques P., editor
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- 1984
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83. A 13C Magnetic Resonance Study of Embryonic Chick Aorta
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Torchia, D. A., Sullivan, C. E., Sandberg, Lawrence B., editor, Gray, William R., editor, and Franzblau, Carl, editor
- Published
- 1977
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84. 0.35-T Proton Nuclear Magnetic Resonance Imaging of the Central Nervous System: Clinical Review of 2909 Patients
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Roosen, N., Lins, E., Schirmer, M., Freiwald, M., Stork, W., Gahlen, D., Bock, W. J., Walter, Wendelin, editor, Brandt, Mathias, editor, Klinger, Margareta, editor, and Brock, Mario, editor
- Published
- 1988
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85. Magnetic Resonance Study of Metallic Polyacetylene
- Author
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Bernier, P., Rachdi, F., El Khodary, A., Audenaert, M., Schweizer, R. J., Cardona, Manuel, editor, Fulde, Peter, editor, Queisser, Hans-Joachim, editor, Kuzmany, Hans, editor, Mehring, Michael, editor, and Roth, Siegmar, editor
- Published
- 1985
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86. Appendix
- Author
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Govil, Girjesh, Hosur, Ramakrishna V., Diehl, Peter, editor, Fluck, Ekkehard, editor, Kosfeld, Robert, editor, Govil, Girjesh, and Hosur, Ramakrishna V.
- Published
- 1982
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87. Neuroradiological Evaluation of AIDS Patients: A Prospective Study
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Livian, S., Scotti, G., Pieralli, S., Triulzi, F., Viscani, A., Righi, G., Majno, M., Lazzarin, A., Castagna, A., and Nadjmi, Maschallah, editor
- Published
- 1989
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88. Magnetic-Resonance Approaches to Transition-State Structure
- Author
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Mildvan, Albert S., Gandour, Richard D., editor, and Schowen, Richard L., editor
- Published
- 1978
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89. Magnetic Resonance Studies of Metal Cation Transport Across Biological Membranes: Use Of Paramagnetic Lanthanide Ions
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Balschi, James A., Cirillo, Vincent P., leNoble, William J., Pike, Martin M., Schreiber, Everett C., Jr., Simon, Sanford R., Springer, Charles S., Jr., McCarthy, Gregory J., editor, Silber, Herbert B., editor, Rhyne, James J., editor, and Kalina, Faye M., editor
- Published
- 1982
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90. Continuous measurement of aortic dimensions in Turner syndrome:a cardiovascular magnetic resonance study
- Author
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Steffen Ringgaard, William Stoddard, Christian Trolle, Dhananjay Radhakrishnan Subramaniam, Philippe Backeljauw, Iris Gutmark-Little, Ephraim Gutmark, Kristian H. Mortensen, Goutham Mylavarapu, and Claus Højbjerg Gravholt
- Subjects
Continuous measurement ,Time Factors ,Aorta, Thoracic ,030204 cardiovascular system & hematology ,Severity of Illness Index ,030218 nuclear medicine & medical imaging ,Automation ,0302 clinical medicine ,Maximum diameter ,Turner syndrome ,Magnetic resonance study ,Thoracic aorta ,Whole Body Imaging ,Aorta ,Observer Variation ,Medicine(all) ,Radiological and Ultrasound Technology ,medicine.diagnostic_test ,Middle Aged ,Magnetic Resonance Imaging ,Cardiology ,Disease Progression ,Female ,Centerlines ,Euclidean distance ,Cardiology and Cardiovascular Medicine ,Dilatation, Pathologic ,Adult ,medicine.medical_specialty ,03 medical and health sciences ,Imaging, Three-Dimensional ,Predictive Value of Tests ,medicine.artery ,Internal medicine ,Image Interpretation, Computer-Assisted ,medicine ,Journal Article ,Humans ,Radiology, Nuclear Medicine and imaging ,Angiology ,Aortic Aneurysm, Thoracic ,business.industry ,Research ,Continuous measures ,Reproducibility of Results ,Magnetic resonance imaging ,medicine.disease ,Iterative closest point ,Aortic Dissection ,Case-Control Studies ,Cardiovascular magnetic resonance ,business - Abstract
BACKGROUND: Severity of thoracic aortic disease in Turner syndrome (TS) patients is currently described through measures of aorta size and geometry at discrete locations. The objective of this study is to develop an improved measurement tool that quantifies changes in size and geometry over time, continuously along the length of the thoracic aorta.METHODS: Cardiovascular magnetic resonance (CMR) scans for 15 TS patients [41 ± 9 years (mean age ± standard deviation (SD))] were acquired over a 10-year period and compared with ten healthy gender and age-matched controls. Three-dimensional aortic geometries were reconstructed, smoothed and clipped, which was followed by identification of centerlines and planes normal to the centerlines. Geometric variables, including maximum diameter and cross-sectional area, were evaluated continuously along the thoracic aorta. Distance maps were computed for TS and compared to the corresponding maps for controls, to highlight any asymmetry and dimensional differences between diseased and normal aortae. Furthermore, a registration scheme was proposed to estimate localized changes in aorta geometry between visits. The estimated maximum diameter from the continuous method was then compared with corresponding manual measurements at 7 discrete locations for each visit and for changes between visits.RESULTS: Manual measures at the seven positions and the corresponding continuous measurements of maximum diameter for all visits considered, correlated highly (R-value = 0.77, P CONCLUSIONS: An automated methodology is presented that enables rapid and precise three-dimensional measurement of thoracic aortic geometry, which can serve as an improved tool to define disease severity and monitor disease progression.TRIAL REGISTRATION: ClinicalTrials.gov Identifier - NCT01678274 . Registered - 08.30.2012.
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- 2017
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91. Diffusion imaging-based subdivision of the human hypothalamus: a magnetic resonance study with clinical implications
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Thomas R. Knösche, Friederike Petzold, Alfred Anwander, Harald E. Möller, Stephanie Schindler, Stefan Geyer, Peter Schönknecht, Robert Turner, and Ulrich Hegerl
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Adult ,Male ,Hypothalamus ,Biology ,computer.software_genre ,Brain mapping ,Functional Laterality ,Young Adult ,Imaging, Three-Dimensional ,Voxel ,Physiology (medical) ,Healthy volunteers ,medicine ,Magnetic resonance study ,Humans ,Pharmacology (medical) ,Biological Psychiatry ,Brain Mapping ,medicine.diagnostic_test ,Magnetic resonance imaging ,General Medicine ,Anatomy ,medicine.disease ,Healthy Volunteers ,Psychiatry and Mental health ,Diffusion imaging ,Diffusion Magnetic Resonance Imaging ,Female ,Neurology (clinical) ,Neuroscience ,computer ,Narcolepsy - Abstract
The hypothalamus and its subdivisions are involved in many neuropsychiatric conditions such as affective disorders, schizophrenia, or narcolepsy, but parcellations of hypothalamic subnuclei have hitherto been feasible only with histological techniques in postmortem brains. In an attempt to map subdivisions of the hypothalamus in vivo, we analyzed the directionality information from high-resolution diffusion-weighted magnetic resonance images of healthy volunteers. We acquired T1-weighted and diffusion-weighted scans in ten healthy subjects at 3 T. In the T1-weighted images, we manually delineated an individual mask of the hypothalamus in each subject and computed in the co-registered diffusion-weighted images the similarity of the principal diffusion direction for each pair of mask voxels. By clustering the similarity matrix into three regions with a k-means algorithm, we obtained an anatomically coherent arrangement of subdivisions across hemispheres and subjects. In each hypothalamus mask, we found an anterior region with dorsoventral principal diffusion direction, a posteromedial region with rostro-caudal direction, and a lateral region with mediolateral direction. A comparative analysis with microstructural hypothalamus parcellations from the literature reveals that each of these regions corresponds to a specific group of hypothalamic subnuclei as defined in postmortem brains. This is to our best knowledge the first in vivo study that attempts a delineation of hypothalamic subdivisions by clustering diffusion-weighted magnetic resonance imaging data. When applied in a larger sample of neuropsychiatric patients, a structural analysis of hypothalamic subnuclei should contribute to a better understanding of the pathogenesis of neuropsychiatric conditions such as affective disorders.
- Published
- 2013
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92. Abbreviations of Special Terms for Presentation/Paper Titles in Magnetic Resonance Study
- Author
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Masanori Komi and Junji Shiraishi
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Research Report ,Magnetic Resonance Spectroscopy ,business.industry ,Computer science ,media_common.quotation_subject ,Speech recognition ,General Medicine ,computer.software_genre ,Spelling ,Presentation ,Magnetic resonance study ,Abbreviations as Topic ,Artificial intelligence ,business ,computer ,Reference standards ,Natural language processing ,media_common - Abstract
PURPOSE A large number of abbreviations have been created for various special terms, and used in magnetic resonance (MR) study. However, the use of these abbreviations in the paper title has been restricted by the majority of societies and journals. In this study, we investigated the use of various abbreviations for special terms in MR study in order to clarify which abbreviation could be used in the paper title without spelling. MATERIALS AND METHODS We used two journals, Magnetic Resonance in Medicine (MRM) and Journal of Magnetic Resonance Imaging (JMRI) published by the International Society for Magnetic Resonance in Medicine (ISMRM), which has been considered to be the most advanced society for MR study in the world, as the reference standard for use of the abbreviations. RESULTS Except for some basic abbreviations and specific abbreviations that were used on a long-term basis, the majority of abbreviations were used in the paper title with its full spelling in order to ensure generality. CONCLUSION It is preferable that abbreviations not be used in the title of the or title of the paper.
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- 2013
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93. Letter by Heidbuchel et al Regarding Article, 'Right and Left Ventricular Function and Mass in Male Elite Master Athletes: A Controlled Contrast-Enhanced Cardiovascular Magnetic Resonance Study'
- Author
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Hein Heidbuchel, Andre La Gerche, and Guido Claessen
- Subjects
medicine.medical_specialty ,medicine.diagnostic_test ,biology ,Ventricular function ,Athletes ,business.industry ,Contrast (statistics) ,Magnetic resonance imaging ,030229 sport sciences ,030204 cardiovascular system & hematology ,biology.organism_classification ,03 medical and health sciences ,0302 clinical medicine ,Physiology (medical) ,medicine ,Physical therapy ,Magnetic resonance study ,Human medicine ,Cardiology and Cardiovascular Medicine ,business - Abstract
We were delighted to read the article by Bohm et al1 addressing the potential deleterious impact of exercise on right ventricular (RV) function. This field definitely needs further study. The work was carried out by a renowned group. However, we were surprised by their conclusion “that the hypothesis of an exercise-induced ARVC needs to be questioned,”1 not only because the small study is underpowered but mainly because the conclusion is not supported by the findings. The authors summed up 4 criteria by which to test the hypothesis. The first concerned the ratio of left ventricular end-diastolic volume/right ventricular end-diastolic volume (LVEDV/RVEDV). This test is indirect at best, only …
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- 2016
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94. Response by Bohm et al to Letter Regarding Article, 'Right and Left Ventricular Function and Mass in Male Elite Master Athletes: A Controlled Contrast-Enhanced Cardiovascular Magnetic Resonance Study'
- Author
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Wilfried Kindermann, Tim De Meyer, Jürgen Scharhag, and Philipp Bohm
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Male ,medicine.medical_specialty ,Longitudinal study ,Magnetic Resonance Spectroscopy ,Heart Ventricles ,030204 cardiovascular system & hematology ,Ventricular Function, Left ,Right ventricular cardiomyopathy ,03 medical and health sciences ,0302 clinical medicine ,Physiology (medical) ,Internal medicine ,medicine ,Magnetic resonance study ,Humans ,biology ,medicine.diagnostic_test ,Ventricular function ,Athletes ,business.industry ,Magnetic resonance imaging ,030229 sport sciences ,biology.organism_classification ,Control subjects ,Magnetic Resonance Imaging ,Surgery ,Cohort ,Ventricular Function, Right ,cardiovascular system ,Cardiology ,Cardiology and Cardiovascular Medicine ,business ,Sports - Abstract
We agree with Heidbuchel and colleagues that our findings do not clearly refute the concept of exercise-induced right ventricular (RV) damage because no prospective longitudinal study has been performed so far. However, our finding of marked RV remodeling without functional RV impairment or scarring challenges the notion of an exercise-induced arrhythmogenic right ventricular cardiomyopathy. First, we studied an exclusive cohort of world-class master endurance athletes with a training history of 29±8 years. Such athletes are not as easily available as ambitious recreational athletes, who would not demonstrate an extensive cardiac remodeling as our studied athletes. Our athletes demonstrated clear structural exercise-induced cardiac remodeling with a mild RV chamber size predominance of about 6% (left ventricular end-diastolic volume/right ventricular end-diastolic volume ratio
- Published
- 2016
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95. Brain sexual differentiation and effects of cross-sex hormone treatment in transgenders: A resting-state functional magnetic resonance study
- Author
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Sarah M. Burke, Peggy T. Cohen-Kettenis, Nienke M. Nota, Baudewijntje P.C. Kreukels, Cornelis B. Lambalk, Remi S. Soleman, Martin den Heijer, Dick J. Veltman, Internal medicine, MOVE Research Institute, EMGO - Lifestyle, overweight and diabetes, Obstetrics and gynaecology, ICaR - Ischemia and repair, NCA - Brain mechanisms in health and disease, Amsterdam Neuroscience - Cellular & Molecular Mechanisms, and Medical psychology
- Subjects
medicine.medical_specialty ,Sexual differentiation ,Resting state fMRI ,biology ,Endocrine and Autonomic Systems ,business.industry ,Endocrinology, Diabetes and Metabolism ,Psychiatry and Mental health ,Endocrinology ,Sex hormone-binding globulin ,Internal medicine ,Magnetic resonance study ,medicine ,biology.protein ,business ,Biological Psychiatry - Published
- 2016
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96. Publisher's Note: Optically enabled magnetic resonance study ofAs75andSb121inSi28[Phys. Rev. B92, 195203 (2015)]
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Helge Riemann, Michael Szech, Jeff Z. Salvail, Mike L. W. Thewalt, Phillip Dluhy, Hans-Joachim Pohl, K. J. Morse, Julian Huber, K. Saeedi, Nikolai V. Abrosimov, and Peter B. Becker
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Materials science ,Condensed matter physics ,Magnetic resonance study - Published
- 2016
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97. Insight into hypertrophied hearts: a cardiovascular magnetic resonance study of papillary muscle mass and T1 mapping
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Charlotte Manisty, Derralynn Hughes, Gabriella Captur, Sabrina Nordin, Rebecca Kozor, Shanat Baig, James C. Moon, Gemma A. Figtree, Stuart M. Grieve, Silvia Castelletti, Stefania Rosmini, Thomas A. Treibel, Richard P. Steeds, and Marianna Fontana
- Subjects
Adult ,Male ,medicine.medical_specialty ,Magnetic Resonance Imaging, Cine ,030204 cardiovascular system & hematology ,Left ventricular hypertrophy ,Sensitivity and Specificity ,Severity of Illness Index ,030218 nuclear medicine & medical imaging ,Muscle hypertrophy ,03 medical and health sciences ,0302 clinical medicine ,Internal medicine ,medicine ,Magnetic resonance study ,Humans ,Radiology, Nuclear Medicine and imaging ,cardiovascular diseases ,Papillary muscle ,Aged ,Retrospective Studies ,Observer Variation ,Analysis of Variance ,medicine.diagnostic_test ,business.industry ,Hypertrophic cardiomyopathy ,Magnetic resonance imaging ,General Medicine ,Middle Aged ,Papillary Muscles ,medicine.disease ,Prognosis ,Fabry disease ,United Kingdom ,Radiographic Image Enhancement ,Stenosis ,medicine.anatomical_structure ,Case-Control Studies ,Cardiology ,Fabry Disease ,Female ,Hypertrophy, Left Ventricular ,Cardiology and Cardiovascular Medicine ,business - Abstract
Aims Left ventricular papillary muscles (LVPM) can appear disproportionately hypertrophied, particularly in Fabry disease (FD) where storage appears detectable by cardiovascular magnetic resonance (CMR) T1 mapping. The aim of the study was to measure LVPM mass in heart diseases with left ventricular hypertrophy (LVH) and to gain insight into the mechanisms of LVPM hypertrophy in FD. Methods and results Four hundred and seventy-eight cases were retrospectively recruited: 125 FD, 85 hypertrophic cardiomyopathy (HCM), 67 amyloid, 82 aortic stenosis (AS), 40 hypertension, 79 controls. LVPM contribution to LVM was manually contoured on CMR short axis cines. T1 values (septal, LVPM) were measured using ShMOLLI sequences in FD and controls. LVPM contribution to LVM was highest in LVH+ve FD and significantly increased compared to all other LVH+ve groups (FD 13 ± 3%, HCM 10 ± 3%, amyloid 8 ± 2%, AS 7 ± 3%, hypertension 7 ± 2%, controls 7 ± 1%; P < 0.001). LVH+ve HCM also had significantly increased LVPM. In LVH−ve cohorts, only FD had significantly increased LVPM (11 ± 3%; P < 0.001). In FD there was concordant septal and LVPM T1. LVH+ve FD: when septal T1 was low, LVPM T1 was low in 90%. LVH−ve FD: when septal T1 was normal, LVPM T1 was normal in 70% (indicating no detectable storage); when septal T1 was low, 75% had low LVPM T1 (indicating storage). LVPM hypertrophy was similar between the low and normal septal T1 groups (11 ± 3% vs. 10 ± 3%, P = 0.08). Conclusion Disproportionate hypertrophy of LVPMs in LVH+ve hearts occurred in FD and HCM. This phenomenon also occurred in LVH−ve FD. Low T1 was not always present in FD LVPM hypertrophy, implying additional mechanisms activating hypertrophy signalling pathways.
- Published
- 2016
98. Magnetic Resonance Studies of Membranes and Lipids
- Author
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Metcalfe, J. C., Wallach, Donald F. Hölzl, editor, and Fischer, Herbert, editor
- Published
- 1971
- Full Text
- View/download PDF
99. Functional magnetic resonance study of deliberate deception
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Alexander Korotkov, Svyatoslav Medvedev, and M. V. Kireev
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medicine.medical_specialty ,genetic structures ,medicine.diagnostic_test ,Physiology ,media_common.quotation_subject ,Magnetic resonance imaging ,Audiology ,Deception ,behavioral disciplines and activities ,Developmental psychology ,Functional brain ,Physiology (medical) ,Healthy volunteers ,medicine ,Magnetic resonance study ,Bold fmri ,Imaging technique ,Psychology ,Functional magnetic resonance imaging ,media_common - Abstract
The goal of the study was analysis of the cerebral mechanisms of deliberate deception. The eventrelated functional magnetic resonance (ER fMRI) imaging technique was used to assess the changes in the functional brain activity by means of recording the blood oxygen level-dependent (BOLD) signal. Twelve right-handed healthy volunteers aged 19–44 years participated in the study. The BOLD images were obtained during three experimental trials: deliberate deception, manipulative honest and control truthful trials (catch trials). The deliberate deception and manipulative honest actions were characterized by a BOLD signal increase in the anterior cingulate (Brodmann’s area (BA) 32), frontal (BAs 9/10, 6), and parietal (BA 40) cortices as compared with a truthful response. Comparison of the ER fMRI data with the results of earlier studies where event-related potentials (ERPs) were recorded under similar conditions indicates the involvement of the brain mechanism of error detection in deliberate deception.
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- 2012
- Full Text
- View/download PDF
100. Magnetic resonance study of arsenic bonding sites in ternary chalcogenide glasses
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Salima Mehdiyeva, Eldar Mammadov, P. C. Taylor, D. Bobela, and A. Reyes
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inorganic chemicals ,Chemistry ,Inorganic chemistry ,chemistry.chemical_element ,General Chemistry ,Condensed Matter Physics ,Nmr data ,Ternary chalcogenide ,Crystallography ,Atom ,Materials Chemistry ,Magnetic resonance study ,Electric field gradient ,Arsenic - Abstract
75 As NQR and high-field NMR experiments have been performed on Ge x As y Se 1− x − y glasses. Evolution of As bonding structure from arsenic sites with axially symmetric distribution of the electric field gradient (EFG) to highly asymmetric As surroundings has been revealed. Arsenic atoms form pyramidal structural units in Ge 2 As 2 Se 7 with no evidence of significant concentration of homopolar bonds. In Ge 2 As 2 Se 5 most of arsenic atoms form structural units with two As–As bonds per atom and asymmetric EFG distribution. Arsenic bondings become more complicated in Ge 0.33 As 0.12 Se 0.55 where all arsenic sites are highly distorted. The combination of NQR and NMR data provide valuable information on arsenic bonding dynamics in these glasses.
- Published
- 2011
- Full Text
- View/download PDF
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