Search results for "Random Allocation"
showing 10 items of 182 documents
Lovastatin attenuates ionizing radiation-induced normal tissue damage in vivo.
2009
Abstract Background and purpose HMG-CoA-reductase inhibitors (statins) are widely used lipid-lowering drugs. Moreover, they have pleiotropic effects on cellular stress responses, proliferation and apoptosis in vitro . Here, we investigated whether lovastatin attenuates acute and subchronic ionizing radiation-induced normal tissue toxicity in vivo . Materials and methods Four hours to 24h after total body irradiation (6Gy) of Balb/c mice, acute pro-inflammatory and pro-fibrotic responses were analyzed. To comprise subchronic radiation toxicity, mice were irradiated twice with 2.5Gy and analyses were performed 3weeks after the first radiation treatment. Molecular markers of inflammation and f…
Influence of inspiration to expiration ratio on cyclic recruitment and derecruitment of atelectasis in a saline lavage model of acute respiratory dis…
2015
OBJECTIVE Cyclic recruitment and derecruitment of atelectasis can occur during mechanical ventilation, especially in injured lungs. Experimentally, cyclic recruitment and derecruitment can be quantified by respiration-dependent changes in PaO2 (ΔPaO2), reflecting the varying intrapulmonary shunt fraction within the respiratory cycle. This study investigated the effect of inspiration to expiration ratio upon ΔPaO2 and Horowitz index. DESIGN Prospective randomized study. SETTING Laboratory investigation. SUBJECTS Piglets, average weight 30 ± 2 kg. INTERVENTIONS At respiratory rate 6 breaths/min, end-inspiratory pressure (Pendinsp) 40 cm H2O, positive end-expiratory pressure 5 cm H2O, and FIO2…
Systemic PaO2 oscillations cause mild brain injury in a pig model
2016
OBJECTIVE: Systemic PaO2 oscillations occur during cyclic recruitment and derecruitment of atelectasis in acute respiratory failure and might harm brain tissue integrity. DESIGN: Controlled animal study. SETTING: University research laboratory. SUBJECTS: Adult anesthetized pigs. INTERVENTIONS: Pigs were randomized to a control group (anesthesia and extracorporeal circulation for 20 hr with constant PaO2, n = 10) or an oscillation group (anesthesia and extracorporeal circulation for 20 hr with artificial PaO2 oscillations [3 cycles min⁻¹], n = 10). Five additional animals served as native group (n = 5). MEASUREMENTS AND MAIN RESULTS: Outcome following exposure to artificial PaO2 oscillations…
Prevalence of nocturnal asthma in a general population sample: determinants and effect of aging.
2000
Nocturnal asthma (NA) is important because of clinical and prognostic implications. Previous data on prevalence may be overestimated, because they are derived from selected series. Observations on monitoring of peak expiratory flow in elderly asthmatics suggested that prevalence of NA may increase with age. This study was designed to estimate the prevalence of NA-related symptoms in a sample drawn from a general population and evaluate the role of aging. Subjects (1,100, mean age 41.9, SD 22.8 years) were randomly selected from the lists of seven general practitioners. A questionnaire on nighttime and morning NA-associated symptoms was used and frequency of occurrence was rated as never, so…
Effect of beclomethasone dipropionate on the bronchial responsiveness to propranolol in asthmatics.
1990
The effect of four weeks of treatment with beclomethasone dipropionate (BDP, 500 micrograms twice daily) on the bronchial responsiveness to propranolol was examined in 16 patients with mild asthma in a placebo-controlled, double-blind crossover study. Propranolol was inhaled in doubling concentrations and the results were expressed as the cumulative dose producing a 20 percent fall in FEV1 (PC20). After four weeks of treatment with BDP, the mean FEV1 increased from 82.0 percent predicted to 88.1 percent predicted. The difference was significant (p less than 0.001). Treatment with BDP did not significantly change the responsiveness to propranolol, the geometric mean PC20 being 3.17 mg/ml bef…
Evaluation of routing policies using an interval-valued TOPSIS approach for the allocation rules
2021
Abstract The success of warehouse management in a supply chain widely depends on an efficient and effective retrieve of customer orders, which is known as the picking process. This paper investigates various routing policies of pickers under two different allocation methods of items in a warehouse of fixed layout, and evaluates their performance in terms of the resulting travel distance by means of a simulation approach. The allocation strategies taken into account are the random storage and a multi-criteria approach, called Interval-Value TOPSIS (IV-T), which is expressively proposed in this paper as a new way to solve the storage allocation problem of items in a warehouse. Because of the …
Polimorfismos en el gen de la apolipoproteína E y riesgo de hipercolesterolemia: un estudio de casos y controles en una población laboral de Valencia
2000
Fundamento El gen de la apolipoproteina E (apoE) presenta tres variantes comunes (alelos ɛ2, ɛ3, ɛ4), cuya frecuencia alelica y asociacion con los lipidos plasmaticos varia segun las poblaciones. Nuestro objetivo fue estimar la asociacion entre estas variantes geneticas y el riesgo de hipercolesterolemia en la poblacion mediterranea espanola. Pacientes y metodo Se ha realizado un estudio de casos y controles en una poblacion laboral de Valencia. Se identificaron 330 casos (148 varones y 182 mujeres) con hipercolesterolemia moderada (colesterol total > 200 mg/dl o con tratamiento hipolipemiante) y un intervalo de edad entre 20–60 anos. Se seleccionaron 330 controles normocolesterolemicos apa…
Depletion of cytosolic GSH decreases the ATP levels and viability of synaptosomes from aged mice but not from young mice
1995
The effect of glutathione depletion on the viability of freshly isolated synaptosomes from whole brain was investigated in young and aged mice. Aging did not influence the GSH and ATP levels and the viability of these synaptosomes. However depletion of glutathione caused by the cytosolic glutathione inhibitor diethyl maleate (1 mM) resulted in a significant decline, after 60 min of incubation, in ATP levels and viability in the synaptosomes from aged mice but not in those from young mice. When synaptosomes were incubated in the presence of the mitochondrial glutathione inhibitor ethacrynic acid (0.2 mM) there was a similar decline in glutathione, ATP levels and synaptosomal viability, both …
Sample size in cluster-randomized trials with time to event as the primary endpoint
2011
In cluster-randomized trials, groups of individuals (clusters) are randomized to the treatments or interventions to be compared. In many of those trials, the primary objective is to compare the time for an event to occur between randomized groups, and the shared frailty model well fits clustered time-to-event data. Members of the same cluster tend to be more similar than members of different clusters, causing correlations. As correlations affect the power of a trial to detect intervention effects, the clustered design has to be considered in planning the sample size. In this publication, we derive a sample size formula for clustered time-to-event data with constant marginal baseline hazards…
Alteration of anion gap during almost total plasma replacement with synthetic colloids in piglets
2000
In ten piglets (body weight 8.2-11.6 kg), acid base, electrolyte and anion gap changes were investigated during almost total plasma replacement with hydroxyethyl starch (HES) and modified fluid gelatin (GEL) in saline solution using a cell saver autotransfusion technique. During the study, there were only moderate acid base changes, but marked disturbances in anion balance. At study end, the mean chloride concentration was significantly higher (mmol/l: normal values 97-108, HES 116 +/- 1.5, GEL 108 +/- 1.1, p0.01) and the mean anion gap was significantly lower in the HES group in comparison to the GEL group (mmol/l: normal values 5-14, HES 3 +/- 1.7, GEL 11.9 +/- 0.9, p0.01). It is conclude…