Search results for " Variation"

showing 10 items of 1712 documents

Effect of probe contact pressure on the photoplethysmographic assessment of conduit artery stiffness

2013

Currently, photoplethysmography (PPG) is a frequently studied optical blood pulsation detection tech- nique among biophotonic and biomedical researchers due to the fact that it shows high potential for estimating the arterial stiffness (AS). The extraction of diagnostically useful information requires standardized measurement pro- cedure with good repeatability. However, the effects of a crucially important factor—the optimal contact pressure (CP) of the probe—are often ignored. Also, CP values are not reported to evaluate those effects. It is hypothesized that AS estimated from PPG pulse wave 2nd derivative parameter b∕a is strongly inconsistent when recorded at nonoptimal probe CP. Our pi…

AdultMalemedicine.medical_specialtyMaterials scienceOptical PhenomenaCoefficient of variationBiomedical EngineeringBlood PressureDerivativePulse Wave AnalysisSignalBiomaterialsYoung AdultVascular StiffnessPhotoplethysmogramPressuremedicineHumansPulse wavePhotoplethysmographyBlood VolumePulse (signal processing)Optical DevicesRepeatabilityAtomic and Molecular Physics and OpticsElectronic Optical and Magnetic MaterialsSurgeryTransducerFemaleBiomedical engineeringJournal of Biomedical Optics
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Associations between intracranial pressure, intraocular pressure and mean arterial pressure in patients with traumatic and non-traumatic brain injuri…

2008

Introduction: Anatomical proximity of the eye and the intracranial space is a fact but the existence of physiological and pathophysiological relationships between them is elusive. The objective of this study was to explore anatomical and pathophysiological interactions between the eye and the intracranial space and to assess clinical utility of intraocular pressure measurement in estimation of intracranial pressure in patients with brain injuries and to discover how haemodynamic instability could influence these interactions. Controversy surrounds the recent literature concerning this problem and the consensus has not been achieved. Materials and methods: We evaluated the correlation betwee…

AdultMalemedicine.medical_specialtyMean arterial pressureIntraocular pressuregenetic structuresAdolescentIntracranial PressurePopulationBlood PressureStatistics NonparametricCentral nervous system diseaseTonometry OcularYoung AdultmedicineHumansProspective StudiesComaeducationIntraocular PressureGeneral Environmental ScienceIntracranial pressureAgedObserver Variationeducation.field_of_studybusiness.industryMiddle Agedmedicine.diseaseeye diseasesBlood pressureAnesthesiaBrain InjuriesOrthopedic surgeryGeneral Earth and Planetary SciencesIntracranial pressure monitoringFemalebusinessInjury
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Pancreatic cancer detection with magnetic resonance cholangiopancreatography and endoscopic retrograde cholangiopancreatography: a prospective contro…

2000

Summary Background Magnetic resonance cholangiopancreatography (MRCP) is a non-invasive and increasingly used procedure in cases involving biliary and pancreatic diseases. However, the accuracy of MRCP in differential diagnosis between pancreatic cancer and chronic pancreatitis has never been documented in a large prospective controlled study. Methods 124 patients were recruited for the study, selected from 141 consecutive patients with an average age of 55 years (range 19–80) who presented to our department between February, 1996, and January, 1998, with a strong clinical suspicion of pancreatic cancer. MRCP images were interpreted by a radiologist and a gastroenterologist who were unaware…

AdultMalemedicine.medical_specialtyPancreatic diseaseBiopsySensitivity and SpecificityGastroenterologyPredictive Value of TestsPancreatic cancerInternal medicineBiopsymedicineHumansProspective StudiesAgedAged 80 and overCholangiopancreatography Endoscopic RetrogradeCommon Bile DuctObserver VariationMagnetic resonance cholangiopancreatographyEndoscopic retrograde cholangiopancreatographymedicine.diagnostic_testbusiness.industryBiopsy NeedleCarcinomaPancreatic DuctsGeneral MedicineMiddle Agedmedicine.diseaseMagnetic Resonance ImagingPancreatic Neoplasmsmedicine.anatomical_structurePancreatitisChronic DiseaseFeasibility StudiesPancreatitisFemaleRadiologyDifferential diagnosisPancreasbusinessFollow-Up StudiesThe Lancet
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Diurnal Variation in Maximal and Submaximal Strength, Power and Neural Activation of Leg Extensors in Men: Multiple Sampling Across Two Consecutive D…

2007

This study aimed to compare day-to-day repeatability of diurnal variation in strength and power. Thirty-two men were measured at four time points (07 : 00 - 08 : 00, 12 : 00 - 13 : 00, 17 : 00 - 18 : 00, and 20 : 30 - 21 : 30 h) throughout two consecutive days (day 1 and day 2). Power during loaded squat jumps, torque and EMG during maximal (MVC) and submaximal (MVC40) voluntary isometric knee extension contractions were measured. The EMG/torque ratio during MVC and MVC40 was calculated to evaluate neuromuscular efficiency. A significant time-of-day effect with repeatable diurnal patterns was found in power. In MVC, a significant time-of-day effect was present on day 2, whereas day 1 showed…

AdultMalemedicine.medical_specialtyPhysical Therapy Sports Therapy and RehabilitationSquatElectromyographyIsometric exerciseBody TemperatureAnimal scienceIsometric ContractionmedicineHumansOrthopedics and Sports MedicineMuscle StrengthCircadian rhythmMuscle SkeletalMotor Neuronsmedicine.diagnostic_testMuscle fatigueElectromyographybusiness.industryDiurnal temperature variationRepeatabilityCircadian RhythmPower (physics)Surgerybody regionsLower ExtremityTorqueMuscle FatiguebusinessInternational Journal of Sports Medicine
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Polymorphisms in the SCD1 gene are associated with indices of stearoyl CoA desaturase activity and obesity: a prospective study.

2013

Scope The serum fatty acid (FA) composition is influenced by dietary fat and the endogenous production of FAs. Stearoyl CoA desaturase 1 (SCD1) is the rate-limiting enzyme catalyzing the synthesis of MUFAs from saturated FAs. Variations in SCD1 activity have been associated with obesity, diabetes, or inflammation. We evaluated the associations between genetic variation of the SCD1 gene, SCD1 activity, intake of oil, and obesity in a population-based prospective study in southern Spain. Methods and results We collected phenotypic, metabolic, nutritional, and genetic information. The type of dietary fat was assessed from samples of cooking oil taken from the participants’ kitchens and analyze…

AdultMalemedicine.medical_specialtyPopulationSingle-nucleotide polymorphismBiologyPolymorphism Single NucleotideInternal medicineGenetic variationmedicineHumansPlant OilsGenetic Predisposition to DiseaseCookingObesityProspective StudieseducationOlive OilPhospholipidschemistry.chemical_classificationeducation.field_of_studyFatty acidMiddle Agedmedicine.diseaseObesityDietary FatsEnzyme assayStearoyl-CoA DesaturaseEndocrinologyBiochemistrychemistryHaplotypesSpainbiology.proteinlipids (amino acids peptides and proteins)Stearoyl-CoA desaturase-1Stearoyl-CoA DesaturaseFood ScienceBiotechnologyMolecular nutritionfood research
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Differential associations of cognitive insight components with pretreatment characteristics in first-episode psychosis

2014

An increasing number of studies have focused on cognitive insight (i.e. awareness of one's own thinking) in psychotic disorders. However, little is known about the premorbid and pretreatment correlates of cognitive insight in the early course of psychosis. One hundred and three patients experiencing first-episode psychosis (FEP) were assessed shortly after treatment initiation for cognitive insight. Pretreatment and baseline clinical, functional and neurocognitive characteristics were examined. The self-reflectiveness dimension of cognitive insight was independently associated with clinical insight and executive functioning, whereas self-certainty was associated with premorbid IQ, premorbid…

AdultMalemedicine.medical_specialtyPsychosisMetacognitionNeuropsychological TestsExecutive FunctionYoung AdultCognitionmedicineHumansYoung adultPsychiatryBiological PsychiatryCognitionAwarenessmedicine.diseaseExplained variationSelf ConceptPsychiatry and Mental healthCross-Sectional StudiesPsychotic DisordersSchizophreniaFemaleVerbal memoryPsychologySocial AdjustmentNeurocognitiveClinical psychologyPsychiatry Research
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Impact of Baseline and Induced Dyspnea on the Quality of Life of Patients With COPD

2008

Objective Dyspnea is the main symptom of chronic obstructive pulmonary disease (COPD) and as such is an important determinant of health-related quality of life. It is, however, weakly correlated to severity of obstruction and there is little information available on how it exercises its effect on health-related quality of life. The aims of this study were to identify the determinants of baseline dyspnea and to ascertain how that factor influences the health-related quality of life of patients with COPD. Patients and methods A total of 101 patients with COPD were studied. Tests included full lung function assessment, the bronchial provocation test (n=70), and the 6-minute walk test. The foll…

AdultMalemedicine.medical_specialtyPulmonary Disease Chronic ObstructiveQuality of lifeInternal medicinemedicineHumansIn patientProspective StudiesBaseline (configuration management)Depression (differential diagnoses)AgedAged 80 and overCOPDbusiness.industryGeneral MedicineMiddle AgedExplained variationmedicine.diseaserespiratory tract diseasesDyspneaBronchial provocationQuality of LifePhysical therapyAnxietyFemalemedicine.symptombusinessArchivos de Bronconeumología ((English Edition))
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Inter- and intrarater reliability of two proprioception tests using clinical applicable measurement tools in subjects with and without knee osteoarth…

2017

Abstract Background The therapeutic value of proprioceptive-based exercises in knee osteoarthritis (KOA) management warrants investigation of proprioceptive testing methods easily accessible in clinical practice. Objective To estimate inter- and intrarater reliability of the knee joint position sense (KJPS) test and knee force sense (KFS) test in subjects with and without KOA. Design Cross-sectional test-retest design. Method Two blinded raters performed independently repeated measures of the KJPS and KFS test, using an analogue inclinometer and handheld dynamometer, respectively, in eight KOA patients (12 symptomatic knees) and 26 healthy controls (52 asymptomatic knees). Intraclass correl…

AdultMalemedicine.medical_specialtyRange of Motion Articular/physiologyIntraclass correlationPhysical Therapy Sports Therapy and RehabilitationOsteoarthritisMuscle Strength DynamometerKnee Joint03 medical and health sciencesDisability Evaluation0302 clinical medicinePhysical medicine and rehabilitationReference ValuesmedicineHumans030212 general & internal medicineRange of Motion ArticularReliability (statistics)Aged030203 arthritis & rheumatologyObserver VariationOsteoarthritis Knee/diagnosisbusiness.industryRepeated measures designIntra-rater reliabilityMiddle AgedOsteoarthritis Kneemedicine.diseaseProprioceptionKnee painStandard errorCross-Sectional StudiesPhysical therapyFemaleHuman medicinemedicine.symptombusinessProprioception/physiologyMusculoskeletal sciencepractice
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Left ventricular ejection fraction calculation from automatically selected and processed diastolic and systolic frames in short-axis cine-MRI

2005

International audience; Abstract: The calculation of the left ventricular ejection fraction (LVEF) is dependent upon the accurate measurement of diastolic and systolic left ventricular volumes. Although breath-hold cine magnetic resonance imaging (MRI) allows coverage of the whole cardiac cycle with an excellent time resolution, many authors rely on the visual selection of diastolic and the systolic short-axis slices in order to reduce the postprocessing time. An automatic method was developed to detect the endocardial contour on each image, allowing an automatic selection of the systolic frame. The calculated ejection fraction was compared with radionuclide ventriculography (RNV). Sixty-fi…

AdultMalemedicine.medical_specialtyShort axisHeart diseaseSystoleHeart VentriclesDiastoleMyocardial InfarctionMagnetic Resonance Imaging CineImage processingRadionuclide ventriculography030204 cardiovascular system & hematologyVentricular Function Left030218 nuclear medicine & medical imaging03 medical and health sciencesElectrocardiography0302 clinical medicineDiastoleInternal medicine[INFO.INFO-IM]Computer Science [cs]/Medical ImagingmedicineHumansmagnetic resonance imagingRadiology Nuclear Medicine and imagingRadionuclide VentriculographyAgedObserver VariationEjection fractionRadiological and Ultrasound Technologymedicine.diagnostic_testCardiac cycle[ INFO.INFO-IM ] Computer Science [cs]/Medical Imagingbusiness.industryMagnetic resonance imagingStroke Volumeleft ventricular ejection fractionMiddle Agedmedicine.diseaseimage processingCardiologyFemaleEndothelium Vascularfuzzy logicCardiology and Cardiovascular MedicinebusinessNuclear medicine
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Evoked potential study in facio-scapulo-humeral muscular dystrophy.

1997

Nerve conduction velocities (NCVs), somatosensory (SEPs) and auditory evoked potentials (BAEPs) were recorded in 9 patients with facio-scapulo-humeral dystrophy (FSHD) and in 20 age-matched controls. In FSHD patients a significant increase of the nerve distal sensory latencies and of the absolute SEP latencies revealed a subclinical involvement of the afferent sensory pathways, as well as the abnormal slowing of the later components of the BAEPs, pointed to a central auditory dysfunction. Moreover all patients underwent brain MRI that showed the presence of white matter hyperintense lesions in 4 of them (44%). No correlations were found between individual or total number of SEP and BAEP abn…

AdultMalemedicine.medical_specialtyShoulderNeural ConductionSensory systemSomatosensory systemSeverity of Illness IndexNerve conduction velocityMuscular DystrophiesWhite matterInternal medicineEvoked Potentials SomatosensorymedicineEvoked Potentials Auditory Brain StemHumansMuscular dystrophyAuditory Diseases CentralSubclinical infectionChi-Square DistributionDystrophyBrainGenetic VariationGeneral MedicineMiddle Agedmedicine.diseaseMagnetic Resonance ImagingMedian Nervemedicine.anatomical_structureNeurologySomatosensory evoked potentialCase-Control StudiesFaceCardiologyArmFemaleNeurology (clinical)Tibial NervePsychologyNeuroscienceActa neurologica Scandinavica
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