Search results for "dynamic"

showing 10 items of 12329 documents

In Vitro Percutaneous Penetration of Acyclovir from Solvent Systems and Carbopol 971-P Hydrogels: Influence of Propylene Glycol

2005

The mechanism underlying propylene glycol (PG) effects on acyclovir (ACV) penetration through human epidermis were studied. Solvent systems and Carbopol gels containing increasing percentage of PG (from 0% to 70%, w/w) were used. Viscosity studies of both vehicles were carried out to characterise the influence of rheological behaviour. In solvent systems skin permeation values of ACV increase as the concentration of PG increase yielding a maximum enhancement ratio (ER = 10) for 70% PG. The release rate of ACV from gels was determined. Higuchi's model was used to estimate the apparent diffusion coefficient of the drug. These values show a decrease as the content of PG in the vehicle increase…

AdultSkin AbsorptionAcrylic ResinsAcyclovirPharmaceutical ScienceIn Vitro TechniquesAntiviral AgentsPolyvinyl alcoholDosage formPropanediolExcipientschemistry.chemical_compoundHumansOrganic chemistrySolubilityViscosityChemistryHydrogelsPenetration (firestop)Hydrogen-Ion ConcentrationMiddle AgedPermeationSolventSolubilityPropylene GlycolsSelf-healing hydrogelsSolventsThermodynamicsFemalePolyvinylsAlgorithmsNuclear chemistryJournal of Pharmaceutical Sciences
researchProduct

Mixed predictability and cross-validation to assess non-linear Granger causality in short cardiovascular variability series

2006

A method to evaluate the direction and strength of causal interactions in bivariate cardiovascular and cardiorespiratory series is presented. The method is based on quantifying self and mixed predictability of the two series using nearest-neighbour local linear approximation. It returns two causal coupling indexes measuring the relative improvement in predictability along direct and reverse directions, and a directionality index indicating the preferential direction of interaction. The method was implemented through a cross-validation approach that allowed quantification of directionality without constraining the embedding of the series, and fully exploited the available data to maximise th…

AdultStatistics as TopicBiomedical EngineeringInferenceBlood PressureHealth InformaticsBivariate analysisDirectionalityCross-validationGranger causalityHeart RateStatisticsEconometricsHumansComputer SimulationPredictabilityMathematicsSeries (mathematics)Models CardiovascularNonlinear systemNonlinear DynamicsData Interpretation StatisticalShort-term cardiovascular variabilityRespiratory MechanicsRegression AnalysisFemaleNon-linear predictionLinear approximationAlgorithmsBiomedizinische Technik/Biomedical Engineering
researchProduct

Beta-adrenergic blocking activity and haemodynamic effects in man of K� 1313, a new beta-adrenergic antagonist

1971

The beta-adrenergic blocking activity and haemodynamic effects of o-[2-hydroxy-3-(isopropylamino)-propoxy]-benzonitril (Ko 1313) have been studied in 22 patients. Antagonism of isoproterenol-induced tachycardia was used as a measure of the beta-adrenergic blocking activity. Ko 1313 1.0 mg had its maximum beta-adrenoceptor blocking effect 5–30 min after intravenous injection. Ko 1313 10.0 mg produced maximum betablockade 1–4 h after oral administration. 1.0 mg Ko 1313 injected intravenously had approximately the same beta-adrenergic blocking effect as 1.0 mg propranolol also given intravenously. After intravenous administration Ko 1313 was 3–4 times as potent as the same dose given orally. A…

AdultTachycardiamedicine.medical_specialtyCardiac outputAdolescentAdrenergic receptorCardiac VolumeAdrenergic beta-AntagonistsAdministration OralBlood Pressure1-PropanolPropranololPharmacologyElectrocardiographyHeart RateOral administrationInternal medicineNitrilesHeart ratemedicineHumansPharmacology (medical)Cardiac OutputPharmacologyBeta-adrenergic blocking agentPropylaminesbusiness.industryHemodynamicsIsoproterenolGeneral MedicineMiddle AgedAmino AlcoholsPropranololDose–response relationshipEndocrinologyInjections IntravenousSympatholyticsVascular Resistancemedicine.symptombusinessmedicine.drugEuropean Journal of Clinical Pharmacology
researchProduct

Time-Varying Surrogate Data to Assess Nonlinearity in Nonstationary Time Series: Application to Heart Rate Variability

2009

We propose a method to extend to time-varying (TV) systems the procedure for generating typical surrogate time series, in order to test the presence of nonlinear dynamics in potentially nonstationary signals. The method is based on fitting a TV autoregressive (AR) model to the original series and then regressing the model coefficients with random replacements of the model residuals to generate TV AR surrogate series. The proposed surrogate series were used in combination with a TV sample entropy (SE) discriminating statistic to assess nonlinearity in both simulated and experimental time series, in comparison with traditional time-invariant (TIV) surrogates combined with the TIV SE discrimin…

AdultTime FactorsComputer scienceRestBiomedical EngineeringSurrogate dataHeart RateStatisticsHumansHeart rate variabilityEntropy (information theory)Computer SimulationNonstationarityEntropy (energy dispersal)Time seriesEntropy (arrow of time)StatisticModels StatisticalEntropy (statistical thermodynamics)RespirationNonlinear dynamicModels CardiovascularComplexitySample entropyNonlinear systemNonlinear DynamicsAutoregressive modelSettore ING-INF/06 - Bioingegneria Elettronica E InformaticaSurrogate dataTime-varying (TV) autoregressive (AR) modelHeart rate variability (HRV)AlgorithmsEntropy (order and disorder)IEEE Transactions on Biomedical Engineering
researchProduct

Cervical carcinoma: standard and pharmacokinetic analysis of time-intensity curves for assessment of tumor angiogenesis and patient survival

1999

Since detailed knowledge regarding the pathophysiological properties—which in turn are responsible for differences in contrast enhancement—remain fairly undetermined, it was the aim of this study (i) to examine the association of standard and pharmacokinetic analysis of time-intensity curves in dynamic MRI with histomorphological markers of tumor angiogenesis (microvessel density [MVD]; vascular endothelial growth factor [VEGF]) and (ii) to determine the ultimate value of a histomorphological and a dynamic MRI approach by correlation of those data with disease outcome in patients with primary cancer of the uterine cervix. Pharmacokinetic parameters (amplitude A, exchange rate constantk 21) …

AdultVascular Endothelial Growth Factor APathologymedicine.medical_specialtyTime FactorsBiophysicsUterine Cervical NeoplasmsEndothelial Growth Factorschemistry.chemical_compoundText miningPharmacokineticsBiomarkers TumormedicineHumansRadiology Nuclear Medicine and imagingSurvival analysisCervical cancerLymphokinesNeovascularization PathologicRadiological and Ultrasound TechnologyVascular Endothelial Growth Factorsbusiness.industryMicrocirculationGold standard (test)Middle Agedmedicine.diseaseMagnetic Resonance ImagingPathophysiologySurvival RateVascular endothelial growth factorchemistryDynamic contrast-enhanced MRIFemaleNuclear medicinebusinessMagnetic Resonance Materials in Physics, Biology and Medicine
researchProduct

A first-in-human study of PDC31 (prostaglandin F2  receptor inhibitor) in primary dysmenorrhea

2014

What is the safe and pharmacodynamically active dose range for PDC31 (prostaglandin F2α receptor inhibitor) in patients with primary dysmenorrhea (PD)?The 1 mg/kg/h dose of PDC31 appears to be safe and potentially effective in reducing intrauterine pressure (IUP) and pain associated with excessive uterine contractility when given as a 3-h infusion in patients with PD.PDC31 has previously been shown to reduce the duration and strength of PGF2α-induced contractions in human uterine myometrial strip models and to delay delivery in animal models of preterm labor.This was a prospective, multi-center, dose-escalating first-in-human Phase I study conducted from March 2011 to June 2012. A total of …

AdultVisual analogue scaleUterusPlaceboDrug Administration ScheduleUterine contractionYoung AdultDysmenorrheaPharmacokineticsInfusion ProceduremedicineHumansProspective StudiesAdverse effectDose-Response Relationship Drugbusiness.industryRehabilitationObstetrics and GynecologyTreatment Outcomemedicine.anatomical_structureReproductive MedicineAnesthesiaPharmacodynamicsFemalemedicine.symptomPeptidesbusinessHuman Reproduction
researchProduct

In Patients with Grade I and II Ankle Sprains, Dynamic Taping Seems to Be Helpful during Certain Tasks, Exercises and Tests in Selected Phases of the…

2022

We aimed to investigate changes in postural stability on a stable surface after the application of dynamic tape for patients with inversion ankle sprains. This study enrolled 30 patients (age 25.5 ± 8.0 years) with grade I and II ankle sprains, which occurred 7–21 days before enrolment. Postural stability (balance, coordination, feedback) was assessed before and after the application of dynamic tape using a stabilographic platform. Three 32-s exercises were performed on the stabilographic platform, one with eyes open, one with eyes closed and one with visual feedback. After the application of dynamic tape, an improvement was observed in terms of the mean radius of sway (4.2 &pl…

AdultYoung Adultdynamic tape; ankle sprain; kinesiology taping; postural stability; rehabilitationAdolescentHealth Toxicology and MutagenesisSprains and StrainsPublic Health Environmental and Occupational HealthHumansAnkle InjuriesPostural BalanceAnkle JointExercise TherapyInternational Journal of Environmental Research and Public Health
researchProduct

Automatic Detection of Left Ventricular Contours from Cardiac Cine Magnetic Resonance Imaging Using Fuzzy Logic

1999

Gated cardiac cine magnetic resonance imaging provides accurate dynamic data of the left ventricular function. However, the manual extraction of important physiologic parameters such as myocardium wall thickness and left ventricular volumes is invariably time consuming and subjective. To reduce the variability and time constraints inherent in observer contour tracing, the authors developed an automatic left ventricle contour-detection method.The purpose was to apply fuzzy logic-based automatic contour detection to identification of endocardial and epicardial borders in short-axis magnetic resonance images. The automatic contouring was compared with manual tracing using the calculated ejecti…

Adultmedicine.diagnostic_testVentricular functionComputer scienceDynamic dataMyocardial InfarctionMagnetic Resonance Imaging CineStroke VolumeMagnetic resonance imagingGeneral MedicineMiddle AgedFuzzy logicManual extractionFuzzy LogicImage Processing Computer-Assistedcardiovascular systemmedicineHumansVentricular FunctionRadiology Nuclear Medicine and imagingcardiovascular diseasesWall thicknessAgedBiomedical engineeringInvestigative Radiology
researchProduct

Efficacy of short-term psychodynamic psychotherapy (STPP) with depressed breast cancer patients: results of a randomized controlled multicenter trial.

2014

BACKGROUND There is a lack of trials of psychodynamic treatments of depression in breast cancer patients. The purpose of this trial was to determine the efficacy of short-term psychodynamic psychotherapy (STPP) in non-metastatic breast cancer patients diagnosed with depression, one of the most frequent mental comorbidities of breast cancer. PATIENTS AND METHODS In a multicenter prospective trial, 157 breast cancer patients with comorbid depression were randomized to either individual STPP (intervention group, N=78) or 'treatment as usual' (control group, TAU, N=79). As our primary outcome measure, we hypothesized a higher rate of remission defined as no diagnosis of depression (Structured C…

Adultmedicine.medical_specialtyAdolescentBreast NeoplasmsHospital Anxiety and Depression ScaleYoung AdultBreast cancerQuality of lifeInternal medicineMulticenter trialmedicineHumansProspective StudiesPsychiatryDepression (differential diagnoses)AgedPsychodynamic psychotherapyIntention-to-treat analysisbusiness.industryDepressionHematologyMiddle Agedmedicine.diseaseComorbidityTreatment OutcomeOncologyQuality of LifeFemalebusinessPsychotherapy PsychodynamicAnnals of oncology : official journal of the European Society for Medical Oncology
researchProduct

Influence of early life risk factors and lifestyle on systemic vascular resistance in later adulthood : the cardiovascular risk in young Finns study

2021

Purpose: There are limited data available concerning the effects of lifetime risk factors and lifestyle on systemic hemodynamics, especially on systemic vascular resistance. The purpose of the study was to evaluate how lifetime cardiovascular risk factors (body mass index (BMI), high-density lipoprotein, low-density lipoprotein, triglycerides, systolic blood pressure, blood glucose) and lifestyle factors (vegetable consumption, fruit consumption, smoking and physical activity) predict systemic vascular resistance index (SVRI) and cardiac index (CI) assessed in adulthood. Materials and Methods: Our study cohort comprised 1635 subjects of the Cardiovascular Risk in Young Finns Study followed …

Adultmedicine.medical_specialtyAdolescentCardiac indexHemodynamicsBlood Pressure3121 Internal medicineBody Mass IndexYoung AdultRisk FactorsInternal medicineInternal MedicinemedicineHumansRisk factorChildLife StyleFinlandmedicine.diagnostic_testbusiness.industryGeneral Medicine3126 Surgery anesthesiology intensive care radiologyImpedance cardiographyBlood pressuremedicine.anatomical_structureCardiovascular DiseasesHeart Disease Risk FactorsCohortVascular resistanceFemaleVascular Resistance3111 BiomedicineCardiology and Cardiovascular MedicinebusinessBody mass index
researchProduct