Search results for "Solutions"

On a Robin (p,q)-equation with a logistic reaction

2019

We consider a nonlinear nonhomogeneous Robin equation driven by the sum of a \(p\)-Laplacian and of a \(q\)-Laplacian (\((p,q)\)-equation) plus an indefinite potential term and a parametric reaction of logistic type (superdiffusive case). We prove a bifurcation-type result describing the changes in the set of positive solutions as the parameter \(\lambda \gt 0\) varies. Also, we show that for every admissible parameter \(\lambda \gt 0\), the problem admits a smallest positive solution.

Pancreatic islets from non-heart beating donor pig: Two-layer preservation method in an in vitro porcine model

2011

Purpose Pancreata from non-heart beating donors could represent an unlimited source of islets if their cell viability can be efficiently preserved during the time necessary to process the organs by the use of a better solution of preservation compared to the classic University of Wisconsin solution. The aim of this study was to determine whether it is possible to obtain functioning “alive islets” from non-heart-beating donors by comparing, on a porcine model, the classic “UW ice-store” method with a two-layer cold storage method (TLM) using oxygenated Perfluorocarbons (PFC) and UW. Methods Whole pancreata were harvested from 20 NHBDs female pigs with similar characteristics and preserved fo…

Ischemic type biliary lesions in histidine-tryptophan-ketoglutarate (HTK) preserved liver grafts.

2006

Ischemic type biliary lesions lead to considerable morbidity following orthotopic liver transplantation. The exact pathogenesis is unknown. One major hypothesis is that insufficient perfusion of the arterial vessels of the biliary tree, especially under perfusion with the high viscous University of Wisconsin solution, might be responsible for ischemic type biliary lesions. Due to low viscosity, HTK solution is reported to have a lower incidence of biliary complications. However, there is no data concerning ischemic type biliary lesions in HTK preserved livers. In this paper we report our results after orthotopic liver transplantation with special regard to ischemic type biliary lesions in …

pH stability of ophthalmic solutions.

2004

Background In this study, we evaluated the pH value of 17 ophthalmic solutions, and we investigated whether the pH of these solutions changed over time after the bottle was opened. Methods Fifteen bottles of each type of solution were chosen at random from different production lots. A 0.05-ml increment was taken from each bottle and was measured daily using a micropH 2002 Crison pH-meter over a period of 30 days. Results The results revealed differences between the pH values of the solutions; nine solutions presented pH values within ocular comfort range and eight solutions presented pH values between 3.5 and 6.4. Ten solutions presented non-statistically significant variations over time ( …

Macular edema: Miscellaneous.

2010

International audience; Abstract. This article provides the reader with practical information to be applied to the various remaining causes of macular edema. Some macular edemas linked to ocular diseases like radiotherapy after ocular melanomas remained of poor functional prognosis due to the primary disease. On the contrary, macular edemas occurring after retinal detachment or after some systemic or local treatment use are often temporary. Macular edema associated with epiretinal membranes or vitreomacular traction is the main cause of poor functional recovery. However, the delay to observe a significant improvement of vision after surgery should be long, as usually observed in tractional …

Letter regarding article titled ‘Microembolism during foam sclerotherapy of varicose veins’ in the New England Journal of Medicine

2008

Myocardial Protection by Retrograde Cardioplegic Perfusion in the Presence of Acute Coronary Artery Obstruction: An Experimental Study

1992

To investigate retrograde delivery of cardioplegic solutions as a means of enhancing myocardial protection in the presence of coronary artery occlusion, a two-part experimental model was devised. In part 1 (in vitro) the possibility of retroperfusing the entire myocardium during acute occlusion of the left anterior descending artery (LAD) was assessed. In part 2 (in vivo) acute LAD occlusion was performed in dogs, and during 2 hours of aortic cross-clamping crystalline cardioplegic solution was infused at 20-minute intervals. In group I the infusion was antegrade, via the aortic root, and in group II it was retrograde, via the coronary sinus. Thereafter the LAD snare was released and the do…

Hypoosmolar conditions reduce extracellular volume fraction and enhance epileptiform activity in the CA3 region of the immature rat hippocampus

2006

The osmolarity of the extracellular space (ECS) compartment is an important factor determining the excitability of neuronal tissue. In the adult hippocampus an important role of osmolarity and ECS diffusion parameters on the susceptibility to epileptic events is well established, but the influence of hypo- and hyperosmolar conditions on the immature hippocampus remains elusive. To investigate the influence of osmolarity on epileptiform activity, extracellular field potentials were recorded in the CA3 region of hippocampal slices of immature (postnatal days 4-7) Wistar rats. The ECS diffusion parameters were determined by the real-time tetramethylammonium (TMA+) iontophoretic method with ion…

Dynamic in vitro dehydration patterns of unworn and worn silicone hydrogel contact lenses.

2008

Purpose: To evaluate the effect of wear on dynamic in vitro dehydration of silicone hydrogel (Si-Hi) contact lens (CL) using a previously described gravimetric procedure. Methods: Five different silicone hydrogel (Si-Hi) contact lenses (CL) were evaluated after being worn by patients under daily wear conditions for 15 days to 1 month. Lenses were conditioned and disinfected with a multipurpose solution after each day of wear. Lenses were left to dehydrate in an analytical balance under controlled conditions of temperature and relative humidity and the results compared with data from new lens samples of the same power and material. Several quantitative parameters were obtained and compared b…

The influence of Ca2+ antagonists on the ciliary activity of the guinea pig trachea.

1990

The ciliary activity of the guinea pig tracheal respiratory epithelium was measured using a photoelectric device. Fourteen animals were administered 75 mg diltiazem/kg body weight 2 days, 1 day and 4 h prior to the investigation. Thirteen animals served as controls. In the pretreated group, the mean ciliary stroke frequency (13.4 +/- 3.0 Hz) was significantly lower (P = 0.02) than in the control group (16.6 +/- 3.7 Hz). The application of aerosolized 0.3 mmol/l nifedipine solution on the tracheal preparations of the control animals also significantly reduced the stroke frequency (P = 0.02). The ciliary activity never dropped beyond a frequency of about 8 Hz. The most probable interpretation…