Search results for "Elastic"

showing 10 items of 2162 documents

Exercise stress CMR reveals reduced aortic distensibility and impaired right-ventricular adaptation to exercise in patients with repaired tetralogy o…

2018

International audience; The aim of our study was to evaluate the feasibility of exercise cardiac magnetic resonance (CMR) in patients with repaired tetralogy of Fallot (RTOF) and to assess right and left ventricular adaptation and aortic wall response to exercise in comparison with volunteers.Methods11 RTOF and 11 volunteers underwent prospective CMR at rest and during exercise. A supine bicycle ergometer was employed to reach twice the resting heart rate during continuous exercise, blood pressure and heart rate were recorded. Bi-ventricular parameters and aortic stiffness were assessed using accelerated cine sequences and flow-encoding CMR. A t-test was used to compare values between group…

MalePhysical-ExerciseVentricular Dysfunction RightBlood PressureVascular MedicineVentricular Dysfunction Left[SPI]Engineering Sciences [physics]Heart RateMedicine and Health SciencesPublic and Occupational HealthProspective StudiesCardiac OutputMaterialsAortaTreadmillQRHeartRegurgitationMagnetic Resonance ImagingSports SciencePulmonary Valve-ReplacementPhysical SciencesTetralogy of FallotMagnetscardiovascular systemMedicineFemale[SDV.IB]Life Sciences [q-bio]/BioengineeringAnatomyResearch ArticleAdultCardiac VentriclesScienceHeart VentriclesRestMaterials ScienceCardiologyStress PhysiologicalAscending AortaHumansSports and Exercise MedicineExerciseCardiac MriHemodynamicsBiology and Life SciencesStroke VolumePhysical ActivityElasticityPhysical FitnessCongenital Heart-DiseaseExercise TestCardiovascular AnatomyRate-Pressure ProductFeasibility StudiesBlood VesselsArterial Stiffness
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Comparison of neutron and X-ray scattering of dilute myoglobin solutions.

1975

Experimental results obtained by neutron scattering of dilute solutions of myoglobin are compared with those obtained by X-ray scattering. X-ray scattering remains the more powerful technique at wider angles above 0.3 A−1, where neutron experiments are less accurate because of low coherent scattering probability and high incoherent background. Neutron scattering is preferable at momentum transfers below 0.2 A−1; the conditions for applying the contrast variation method for the evaluation of the three basic scattering functions, which are due to shape and internal structure, equation (3), are ideally fulfilled in this region. Furthermore, neutrons allow observation of the hydrogen-deuterium …

MaleProtein ConformationAstrophysics::High Energy Astrophysical PhenomenaNeutron scatteringInelastic scatteringOpticsStructural BiologyMethodsAnimalsScattering RadiationMolecular BiologyPhysicsNeutronsQuasielastic scatteringScatteringbusiness.industryMyoglobinX-RaysWhalesDeuteriumSmall-angle neutron scatteringComputational physicsQuasielastic neutron scatteringScattering theoryBiological small-angle scatteringbusinessMathematicsJournal of molecular biology
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Compliance and Pulse Wave Velocity Assessed by MRI Detect Early Aortic Impairment in Young Patients With Mutation of the Smooth Muscle Myosin Heavy C…

2008

Purpose To evaluate aortic elasticity with MRI on young asymptomatic individuals with mutation of the smooth muscle myosin heavy chain in whom aortic enlargement is not present. Materials and Methods Aortic compliance, aortic distensibility, and pulse wave velocity (PWV) were semiautomatically measured from MRI in 8 asymptomatic subjects having a mutation of the MYH11 gene (M+) and 21 nonmutated relatives (M−) of similar age, sex, and blood pressure characteristics. Results Despite a similar aortic diameter in both groups, the aortic compliance and distensibility were significantly lower in M+ subjects compared with M− (0.84 ± 0.33 versus 2.03 ± 0.54 mm2/mmHg, 1.18 ± 0.62 10−3 versus 5.11 ±…

MalePulsatile flow030204 cardiovascular system & hematology030218 nuclear medicine & medical imaging0302 clinical medicinemagnetic resonance imaginggeneticsPulse wave velocityComputingMilieux_MISCELLANEOUSmedicine.diagnostic_test[ INFO.INFO-IM ] Computer Science [cs]/Medical ImagingPrognosisPulsatile FlowAortic valve stenosiscardiovascular systemCardiologyElasticity Imaging TechniquesFemalemedicine.symptomAlgorithmsBlood Flow VelocityAdultmedicine.medical_specialtypulse wave velocityAortic Valve InsufficiencySensitivity and SpecificityAsymptomaticYoung Adult03 medical and health sciencesElastic Modulusmedicine.arteryInternal medicineImage Interpretation Computer-Assistedmedicine[INFO.INFO-IM]Computer Science [cs]/Medical ImagingHumansGenetic Predisposition to DiseaseRadiology Nuclear Medicine and imagingAortaMyosin Heavy ChainsReceiver operating characteristicbusiness.industryReproducibility of ResultsMagnetic resonance imagingAortic Valve StenosisImage Enhancementmedicine.diseaseaortaBlood pressureMutationelasticitybusiness
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Increased liver stiffness is associated with mortality in HIV/HCV coinfected subjects: The French nationwide ANRS CO13 HEPAVIH cohort study

2019

Background The association between liver stiffness measurements (LSM) and mortality has not been fully described. In particular the effect of LSM on all-cause mortality taking sustained virological response (SVR) into account needs further study. Methods HIV/HCV participants in the French nation-wide, prospective, multicenter ANRS CO13 HEPAVIH cohort, with ≥1 LSM by FibroScan (FS) and a detectable HCV RNA when the first valid FS was performed were included. Cox proportional hazards models with delayed entry were performed to determine factors associated with all-cause mortality. LSM and SVR were considered as time dependent covariates. Results 1,062 patients were included from 2005 to 2015 …

MaleRNA virusesSustained Virologic ResponseMetabolic disordersSocial SciencesHIV InfectionsHepacivirusmedicine.disease_causeGastroenterology0302 clinical medicineImmunodeficiency VirusesRisk FactorsPsychologyAlcohol consumptionProspective Studies030212 general & internal medicineProspective cohort studyPathology and laboratory medicineMultidisciplinaryDeath ratesCoinfectionHepatitis C virusMortality rateQHazard ratioRvirus diseasesHepatitis CMiddle AgedMedical microbiologyAddicts3. Good healthLiverDrug usersVirusesCohortElasticity Imaging TechniquesMedicineFemale030211 gastroenterology & hepatologyFrancePathogensResearch ArticleCohort studyAdultmedicine.medical_specialtyScienceHepatitis C virusLiver fibrosisAddictionGastroenterology and HepatologyAntiviral AgentsMicrobiology03 medical and health sciencesPopulation MetricsInternal medicineRetrovirusesmedicineHumansMortalityLiver diseasesProportional Hazards ModelsNutritionMedicine and health sciencesBiology and life sciencesFlavivirusesPopulation Biologybusiness.industryProportional hazards modelLentivirusOrganismsViral pathogensHIVHepatitis C Chronicmedicine.diseaseHepatitis virusesMicrobial pathogensDiet[SDV.SPEE] Life Sciences [q-bio]/Santé publique et épidémiologie[SDV.SPEE]Life Sciences [q-bio]/Santé publique et épidémiologiebusinessPLOS ONE
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Aortic Function's Adaptation in Response to Exercise-Induced Stress Assessing by 1.5T MRI : A Pilot Study in Healthy Volunteers

2015

AIM:Evaluation of the aortic "elastic reserve" might be a relevant marker to assess the risk of aortic event. Our aim was to compare regional aortic elasticity at rest and during supine bicycle exercise at 1.5 T MRI in healthy individuals. METHODS:Fifteen volunteers (8 men), with a mean age of 29 (23-41) years, completed the entire protocol. Images were acquired immediately following maximal exercise. Retrospective cine sequences were acquired to assess compliance, distensibility, maximum rates of systolic distension and diastolic recoil at four different locations: ascending aorta, proximal descending aorta, distal descending aorta and aorta above the coeliac trunk level. Segmental aortic …

Male[INFO.INFO-IM] Computer Science [cs]/Medical Imaginglcsh:MedicineAorta ThoracicPilot Projects030204 cardiovascular system & hematologyCardiovascular MedicineVascular Medicine030218 nuclear medicine & medical imagingDiagnostic Radiology0302 clinical medicineDiastole[SPI.MECA.BIOM] Engineering Sciences [physics]/Mechanics [physics.med-ph]/Biomechanics [physics.med-ph]Supine PositionMedicine and Health SciencesThoracic aortaPublic and Occupational Healthlcsh:SciencePulse wave velocityAortaMultidisciplinary[ INFO.INFO-IM ] Computer Science [cs]/Medical ImagingRadiology and Imaging[SPI.MECA.BIOM]Engineering Sciences [physics]/Mechanics [physics.med-ph]/Biomechanics [physics.med-ph]Adaptation PhysiologicalHealthy VolunteersSports Science[SDV.MHEP.CSC] Life Sciences [q-bio]/Human health and pathology/Cardiology and cardiovascular systemPulmonary imagingCardiovascular diseasesDescending aortaVentricular pressureCardiologycardiovascular systemBlood pressureFemaleAnatomyResearch ArticleAdultmedicine.medical_specialtySystoleImaging TechniquesHeart rateCardiologyPulse Wave AnalysisResearch and Analysis Methods03 medical and health sciencesVascular StiffnessMagnetic resonance imaging[SDV.MHEP.CSC]Life Sciences [q-bio]/Human health and pathology/Cardiology and cardiovascular systemStress PhysiologicalDiagnostic Medicinemedicine.arteryInternal medicineAscending aortamedicine[INFO.INFO-IM]Computer Science [cs]/Medical ImagingHumansSystoleExerciseAortabusiness.industrylcsh:RBiology and Life SciencesPhysical ActivityElasticityBlood pressurePhysical FitnessCardiovascular AnatomyBlood Vesselslcsh:QSports and exercise medicinebusiness
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The E-modulus of the oocyte is a non-destructive measure of zona pellucida hardening

2021

Reproduction 162(4), 259-266 (2021). doi:10.1530/REP-21-0122

Maleendocrine systemEmbryologyZonaModulusCleavage (embryo)Zona Pellucida GlycoproteinsMiceEndocrinologyHuman fertilizationmedicineAnimalsZona pellucidaElastic modulusZona Pellucidareproductive and urinary physiologybiologyurogenital systemChemistryResearchObstetrics and GynecologyCell Biologybiology.organism_classificationOocyteSpermatozoaSpermFetuin-Bmedicine.anatomical_structureReproductive Medicineembryonic structuresOocytesBiophysicsFemaleReproduction
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Anterior Segment Biometry and Their Correlation with Corneal Biomechanics in Caucasian Children.

2018

Purpose: To assess the relationship between the corneal biomechanical parameters and the anterior segment parameters in Caucasian children. Methods: This study included 293 eyes from 293 healthy children aged between 6 and 17 years. Corneal hysteresis (CH) and corneal resistance factor (CRF) were evaluated with the Ocular Response Analyzer, axial length (AL) with IOLMaster and the anterior segment with Pentacam. Anterior segment parameters obtained were the following: central corneal thickness (CCT), corneal volume (CV), anterior chamber depth (ACD), anterior chamber volume (ACV) and mean anterior and posterior keratometry. Two multiple linear regression models were constructed to assess th…

Malemedicine.medical_specialtyBiometrygenetic structuresAdolescentanterior ocular segmentWhite Peoplelaw.inventionCorneal hysteresisCorrelationCorneaCorneal biomechanics03 medical and health sciencesCellular and Molecular Neuroscience0302 clinical medicinechildrenlawAnterior Eye SegmentReference ValuesStatistical significanceOphthalmologyLinear regressionMedicineHumansChildIntraocular PressureKeratometerbusiness.industryBiomechanicsCorneal TopographyAxial lengtheye diseasesSensory SystemsElasticityOphthalmologyCross-Sectional Studies030221 ophthalmology & optometryFemalesense organsocular response analyzerbusiness030217 neurology & neurosurgeryCurrent eye research
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A Sequential Algorithm Combining ADAPT and Liver Stiffness Can Stage Metabolic-Associated Fatty Liver Disease in Hospital-Based and Primary Care Pati…

2020

INTRODUCTION Metabolic-associated fatty liver disease is common, with fibrosis the major determinant of adverse outcomes. Population-based screening tools with high diagnostic accuracy for the staging of fibrosis are lacking. METHODS Three independent cohorts, 2 with both liver biopsy and liver stiffness measurements (LSMs, n = 254 and 65) and a population sample (n = 713), were studied. The performance of a recently developed noninvasive algorithm (ADAPT [age, diabetes, PRO-C3 and platelets panel]) as well as aspartate aminotransferase-to-platelet ratio index, fibrosis-4, nonalcoholic fatty liver disease fibrosis score, and LSM was used to stage patients for significant (≥F2) and advanced …

Malemedicine.medical_specialtyBiopsyPopulationGastroenterology03 medical and health sciences0302 clinical medicineFibrosisNon-alcoholic Fatty Liver DiseasePredictive Value of TestsDiabetes mellitusInternal medicineNonalcoholic fatty liver diseasemedicineDiabetes MellitusHumansAspartate Aminotransferaseseducationeducation.field_of_studyHepatologymedicine.diagnostic_testReceiver operating characteristicbusiness.industryPlatelet CountFatty liverGastroenterologyAge FactorsOdds ratioMiddle Agedmedicine.diseaseCollagen Type III030220 oncology & carcinogenesisLiver biopsyElasticity Imaging Techniques030211 gastroenterology & hepatologyFemalebusinessAlgorithmsBiomarkersThe American journal of gastroenterology
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The treatment of venous leg ulcers: a new therapeutic use of iloprost

2007

Background: We conducted a study using an intravenous (i.v.) infusion of iloprost in the treatment of venous ulcers to verify whether the association of i.v. iloprost + local therapy + elastic compression has a favorable effect when compared with traditional treatment with local therapy and elastic compression. Study Design: We evaluated the effects of iloprost in 98 consecutive patients with noncomplicated venous ulcers of lower limbs subdivided into 2 groups: the first group (48 patients) received iloprost in saline solution for 3 weeks and the second group (50 patients) received a venous infusion of a saline solution. The patients were examined at baseline time 0 (first visit) and then a…

Malemedicine.medical_specialtyElastic compressionmedicine.medical_treatmentIschemiaPlacebo groupDrug Administration Schedulelaw.inventionRandomized controlled triallawmedicineHumansSingle-Blind MethodIloprostInfusions IntravenousVeinSalineDose-Response Relationship Drugbusiness.industryvenous ulcersiloprostLeg UlcerSignificant differenceMiddle Agedmedicine.diseaseCombined Modality TherapySurgeryTreatment Outcomemedicine.anatomical_structureDebridementAnesthesiaAnti-Infective Agents LocalFemaleSurgeryVENOUS LEG ULCERS ILOPROSTbusinessPlatelet Aggregation InhibitorsStockings CompressionIloprostmedicine.drug
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Relationship among Corneal Biomechanics, Refractive Error, and Axial Length

2014

Purpose To evaluate the relationship between different ocular and corneal biomechanical parameters in emmetropic and ametropic healthy white children. Methods This study included 293 eyes of 293 healthy Spanish children (135 boys and 158 girls), ranging in age from 6 to 17 years. Subjects were divided according to the refractive error: control (emmetropia, 99 children), myopia (100 children), and hyperopia (94 children) groups. In all cases, corneal hysteresis (CH) and corneal resistance factor (CRF) were evaluated with the Ocular Response Analyzer system. Axial length (AL) and mean corneal power were also measured by partial coherence interferometry (IOLMaster), and central corneal thickne…

Malemedicine.medical_specialtyRefractive errorIntraocular pressureocular parametersAdolescentgenetic structuresAnterior ChamberVisual AcuityEmmetropiaCorneachildrenOphthalmologyHumansMedicinerefractive errorChildIntraocular PressureDioptreÓpticabusiness.industryBiomechanicsHigh myopiaAxial lengthElastic TissueRefractive Errorsmedicine.diseaseeye diseasesBiomechanical PhenomenaAxial Length EyeOphthalmologyCross-Sectional Studiesagecorneal biomechanical propertiesRegression AnalysisOptometryFemaleMultiple linear regression analysissense organsbusinessTomography Optical CoherenceOptometryOptometry and Vision Science
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