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1.
AJNR Am J Neuroradiol ; 38(7): 1362-1367, 2017 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-28473340

RESUMEN

BACKGROUND AND PURPOSE: General anesthesia during endovascular treatment of acute ischemic stroke may have an adverse effect on outcome compared with conscious sedation. The aim of this study was to examine the impact of the type of anesthesia on the outcome of patients with acute ischemic stroke treated with the Solitaire stent retriever, accounting for confounding factors. MATERIALS AND METHODS: Four-hundred one patients with consecutive acute anterior circulation stroke treated with a Solitaire stent retriever were included in this prospective analysis. Outcome was assessed after 3 months by the modified Rankin Scale. RESULTS: One-hundred thirty-five patients (31%) underwent endovascular treatment with conscious sedation, and 266 patients (69%), with general anesthesia. Patients under general anesthesia had higher NIHSS scores on admission (17 versus 13, P < .001) and more internal carotid artery occlusions (44.6% versus 14.8%, P < .001) than patients under conscious sedation. Other baseline characteristics such as time from symptom onset to the start of endovascular treatment did not differ. Favorable outcome (mRS 0-2) was more frequent with conscious sedation (47.4% versus 32%; OR, 0.773; 95% CI, 0.646-0.925; P = .002) in univariable but not multivariable logistic regression analysis (P = .629). Mortality did not differ (P = .077). Independent predictors of outcome were age (OR, 0.95; 95% CI, 0.933-0.969; P < .001), NIHSS score (OR, 0.894; 95% CI, 0.855-0.933; P < .001), time from symptom onset to the start of endovascular treatment (OR, 0.998; 95% CI, 0.996-0.999; P = .011), diabetes mellitus (OR, 0.544; 95% CI, 0.305-0.927; P = .04), and symptomatic intracerebral hemorrhage (OR, 0.109; 95% CI, 0.028-0.428; P = .002). CONCLUSIONS: In this single-center study, the anesthetic management during stent retriever thrombectomy with general anesthesia or conscious sedation had no impact on the outcome of patients with large-vessel occlusion in the anterior circulation.


Asunto(s)
Anestesia General , Isquemia Encefálica/cirugía , Sedación Consciente , Remoción de Dispositivos/métodos , Procedimientos Endovasculares/métodos , Stents , Accidente Cerebrovascular/cirugía , Anciano , Anciano de 80 o más Años , Remoción de Dispositivos/efectos adversos , Femenino , Humanos , Complicaciones Intraoperatorias/epidemiología , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Complicaciones Posoperatorias/epidemiología , Estudios Prospectivos , Trombectomía/efectos adversos , Tomografía Computarizada por Rayos X , Resultado del Tratamiento
2.
Nanotechnology ; 19(18): 185709, 2008 May 07.
Artículo en Inglés | MEDLINE | ID: mdl-21825705

RESUMEN

Photoinduced second harmonic generation (SHG) in Au nanoparticle-deposited ZnO nanocrystallite (NC) films was explored by applying bicolor coherent treatment of a Nd-YAG laser with wavelength 1.06 µm and its SHG. We have established that coexistence of the ZnO and Au nanoparticles gives a substantially larger SHG output with respect to pure ZnO NC deposited on the glass substrate. It was established that the value of the second order susceptibility is about 23 pm V(-1). Better nonlinear optical susceptibilities were obtained during phototreatment at temperatures near 30-35 °C for the Au doped samples. The samples without gold NCs are temperature independent. Generally an increasing temperature leads to a decrease of the optical SHG.

3.
J Biochem Biophys Methods ; 62(2): 153-62, 2005 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-15680285

RESUMEN

This paper deals with the evolution of concentration field at a single membrane system. Concentration field evolution is described by concentration effect of stable boundary layers, which originate in this system. The concentration effect of boundary layers (CBLE) is studied experimentally on the basis concentration profiles obtained from computer analysis of interferometric pictures of near-membrane regions. Besides experimental results, we also report theoretical investigations and numerical calculations of this effect for two models of membranes (an infinite thin wall and the wall of thickness l). Evolution of concentration field at different distances from membrane surface describes accurately the spatio-temporal structure of the concentration boundary layers (CBLs). Results have shown that their spatial structure is fully established and these layers develop diffusively.


Asunto(s)
Biofisica/métodos , Transporte Biológico , Difusión , Relación Dosis-Respuesta a Droga , Etanol/química , Procesamiento de Imagen Asistido por Computador , Interferometría , Rayos Láser , Membranas Artificiales , Modelos Estadísticos , Modelos Teóricos , Distribución Normal , Programas Informáticos , Termodinámica , Factores de Tiempo
4.
J Dermatolog Treat ; 15(6): 379-86, 2004 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-15764050

RESUMEN

AIM: The objective of our study was to determine which ultrasound power density (0.5 W/cm(2) or 1 W/cm(2)) is more effective at reducing the area and volume of leg ulceration. METHODS: A total of 65 patients with venous ulcers were randomly divided into three groups: A, B and C. In group A, 22 patients were treated with ultrasound rated at 1 W/cm(2) and with compressive therapy. In group B, 21 patients were treated with ultrasound rated at 0.5 W/cm(2) and with compressive therapy. In both groups the patients were treated with a pulsed wave of a duty cycle of 1/5 (impulse time=2 ms, pause time=8 ms) and frequency of 1 MHz. The 22 patients in group C (control group) were subjected to topical pharmacological treatment. RESULTS: We found a statistically significant reduction of the ulcer area, volume and linear dimensions in all three groups of patients. The ulcer area reduction rate was highest in group B. The volume reduction rate in group B was higher than in group A only. The rate of reduction of suppurate area was highest in group B. CONCLUSION: We have demonstrated that ultrasound rated at 0.5 W/cm(2) causes greater and faster changes in the healing process than ultrasound rated at 1 W/cm(2).


Asunto(s)
Terapia por Ultrasonido , Úlcera Varicosa/terapia , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Persona de Mediana Edad
5.
Gen Physiol Biophys ; 21(2): 115-46, 2002 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-12236542

RESUMEN

Results of an experimental study of volume osmotic flows in a single-membrane osmotic-diffusive cell, which contains a horizontal, microporous, symmetrical polymer membrane separating water and binary or ternary electrolyte solutions are presented. In the experimental set-up, water was placed on one side of the membrane. The opposite side of the membrane was exposed to binary or ternary solutions. As binary solutions, aqueous potassium chloride or ammonia solutions were used, whereas potassium chloride in 0.25 mol x l(-1) aqueous ammonia solution or ammonia in 0.1 mol x l(-1) aqueous potassium chloride solution were used as ternary solutions. Two (A and B) configurations of a single-membrane osmotic-diffusive cell in a gravitational field were studied. In configuration A, water was placed in a compartment above the membrane and the solution below the membrane. In configuration B the position of water and solution was reversed. Furthermore, the effect of amplification of volume osmotic flows of electrolyte solutions in the single-membrane osmotic-diffusive electrochemical cell was demonstrated. The thermodynamic models of the flux graviosmotic and amplification effects were developed, and the volume flux graviosmotic effect for configurations A and B of a single-membrane osmotic-diffusive cell was calculated. The results were interpreted within the conventional instability category, increasing the diffusion permeability coefficient value for the system: concentration boundary layer/membrane/concentration boundary layer.


Asunto(s)
Amoníaco/química , Celulosa/análogos & derivados , Celulosa/química , Electrólitos/química , Membranas Artificiales , Modelos Químicos , Cloruro de Potasio/química , Simulación por Computador , Difusión , Electroquímica , Gravitación , Ósmosis , Presión Osmótica , Polímeros/química , Reproducibilidad de los Resultados , Reología/métodos , Sensibilidad y Especificidad , Soluciones , Termodinámica , Agua/química
6.
Polim Med ; 31(1-2): 45-52, 2001.
Artículo en Polaco | MEDLINE | ID: mdl-11712202

RESUMEN

In this paper the pressure gravidiffusive model equation in a single-membrane osmotic-diffusive cell is elaborated. In this cell the flat, microporous and symmetric polymeric membrane so-called Nephrophane positioned horizontally separated water and binary (aqueous glucose or aqueous ethanol) or ternary (glucose in 0.2 mol.l-1 aqueous ethanol or ethanol in 0.05 mol.l-1 aqueous glucose) non-electrolyte solutions. The calculations of pressure gravidiffusive effects for the configurations A and B of the single-membrane osmotic-diffusive cell were elaborated. In configuration A solution was placed in compartment below membrane and in configuration B--above membrane. The calculated result are interpreted in terms of the convective instability that increases the diffusive permeability coefficient of complex: concentration boundary layer/membrane/concentration boundary layer.


Asunto(s)
Membranas Artificiales , Modelos Biológicos , Soluciones/química , Membrana Celular/metabolismo , Difusión , Solución Hipertónica de Glucosa/química , Gravitación , Ósmosis , Permeabilidad , Polímeros , Presión , Agua/química
7.
Polim Med ; 31(3-4): 25-32, 2001.
Artículo en Polaco | MEDLINE | ID: mdl-11935936

RESUMEN

In this paper the results of study pressure graviosmotic effect for a double-membrane osmotic-diffusive cell, in which series of two (Ml and M(r)), microporous and symmetrical flat polymeric membranes (Nephrophane and Cellulose IMP-1) separate three compartments (l, m, r) containing the heterogeneous and binary (aqueous glucose or ethanol solutions) or ternary (glucose solutions in 0.75 mole.l-1 aqueous ethanol solution or ethanol solutions in 0.1 mole.l-1 aqueous glucose solution) non-ionic solutions. In this system the solution concentrations fulfill the condition Ckl > Ckm > Ckr. The inter-membrane compartment (m) consists of the infinitesimal layer of solution. The volume of compartment m and external compartment (l and r) fulfill the conditions Vm-->0 and Vl = Vr-->infinity respectively. The calculations of pressure graviosmotic effect for configurations A and B of the double-membrane osmotic-diffusive cell were elaborated. In configuration A solution was placed in compartment below membrane M(r) and water above membrane Ml. In configuration B solution was placed in compartment above membrane Ml and water below membrane Ml. These calculated results are interpreted in terms of the convective instability that increases the diffusive permeability coefficients of complexes: concentration boundary layers (membrane Ml or M(r)) concentration boundary layer.


Asunto(s)
Membranas Artificiales , Modelos Biológicos , Presión Osmótica , Soluciones/química , Difusión , Gravitación , Ósmosis , Permeabilidad , Polímeros , Propiedades de Superficie
8.
Polim Med ; 31(3-4): 33-41, 2001.
Artículo en Polaco | MEDLINE | ID: mdl-11935938

RESUMEN

In this paper the results of study flux gravidiffusive effect for a double-membrane osmotic-diffusive cell, in which series of two (Ml and M(r)), microporous and symmetrical flat polymeric membranes (Nephrophane and Cellulose IMP-1). These membranes separate three compartments (l, m, r) containing the heterogeneous and binary (aqueous glucose or ethanol solutions) or ternary (glucose solutions in 0.75 mole.l-1 aqueous ethanol solution or ethanol solutions in 0.1 mole.l-1 aqueous glucose solution) non-ionic solutions. The solution concentrations fulfil the condition Ckl > Ckm > Ckr. The inter-membrane compartment (m) consists of the infinitesimal layer of solution. The volume of compartment m and external compartment (l and r) fulfill the conditions Vm-->0 and Vl = Vr-->infinity respectively. The study of flux gravidiffusive effect for configurations A and B of the double-membrane osmotic-diffusive cell were elaborated. In configuration A solution was placed in compartment below membrane M(r) and water above membrane Ml. In configuration B solution was placed in compartment above membrane Ml and water below membrane Ml. These results are interpreted in terms of the convective instability that increases the diffusive permeability coefficients of complexes: concentration boundary layers/membrane Ml or M(r)/concentration boundary layer.


Asunto(s)
Membranas Artificiales , Modelos Biológicos , Presión Osmótica , Soluciones/química , Difusión , Etanol/química , Solución Hipertónica de Glucosa/química , Gravitación , Ósmosis , Permeabilidad , Polímeros , Propiedades de Superficie
9.
Polim Med ; 31(3-4): 42-51, 2001.
Artículo en Polaco | MEDLINE | ID: mdl-11935939

RESUMEN

In this paper the results of study flux graviosmotic effect for a double-membrane system, in which two (Ml and M(r)), microporous and symmetrical flat polymeric membranes (Nephrophane and Cellulose IMP-1) separate three compartments (l, m, r) containing the heterogeneous and binary (aqueous glucose or ethanol solutions) or ternary (glucose solutions in 0.75 mole.l-1 aqueous ethanol solution or ethanol solutions in 0.1 mol.l-1 aqueous glucose solution) non-ionic solutions. In this system the solution concentrations fulfill the condition Ckl > Ckm > Ckr. The inter-membrane compartment (m) consists of the infinitesimal layer of solution. The volume of compartment m and external compartment (l and r) fulfill the conditions Vm-->0 and Vl = Vr-->infinity respectively. The calculations of flux graviosmotic effect for configurations A and B of the double-membrane osmotic-diffusive cell were elaborated. In configuration A solution was placed in compartment below membrane M(r) and water above membrane Ml. In configuration B solution was placed in compartment above membrane Ml and water below membrane Ml. These calculated results are interpreted in terms of the convective instability that increases the diffusive permeability coefficients of complexes: concentration boundary layers/membrane Ml or M(r)/concentration boundary layer.


Asunto(s)
Membranas Artificiales , Modelos Biológicos , Presión Osmótica , Soluciones/química , Difusión , Etanol/química , Solución Hipertónica de Glucosa/química , Gravitación , Ósmosis , Permeabilidad , Polímeros , Propiedades de Superficie
10.
Polim Med ; 30(1-2): 21-44, 2000.
Artículo en Inglés | MEDLINE | ID: mdl-11064886

RESUMEN

Results of experimental study of volume flux in one-membrane system were presented. This system contains horizontal, microporous and symmetrical flat polymeric membrane (Nephrophan), which separate water and electrolyte solution. As binary solutions, aqueous ammonia solutions, which density is lower than water density, were used. As ternary solutions the ammonia with KC1 (0.1 or 0.2 mole.l-1) in aqueous solution were used. The density of ternary solutions was lower, higher or the same as water density. Two configurations of membrane system (A and B) in gravitational field were studied. In configuration A, water was in compartment over the membrane and the solution was under the membrane. In configuration B the succession was reverse. The thermodynamic model of flux graviosmotic effect was elaborated, and the calculations of this effect were performed for A and B configurations of one membrane system. The experimental results are interpreted in terms of gravitational instability that reduces concentration boundary layer dimensions and increases the diffusion permeability coefficient value of the complex: boundary layer/membrane/boundary layer.


Asunto(s)
Electrólitos/química , Gravitación , Membranas Artificiales , Modelos Biológicos , Ósmosis , Polímeros , Amoníaco/química , Membrana Celular/metabolismo , Difusión , Electrólitos/metabolismo , Permeabilidad , Cloruro de Potasio/química , Reología , Soluciones/química , Soluciones/metabolismo , Termodinámica
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