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1.
AJNR Am J Neuroradiol ; 38(7): 1362-1367, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28473340

RESUMO

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.


Assuntos
Anestesia Geral , Isquemia Encefálica/cirurgia , Sedação Consciente , Remoção de Dispositivo/métodos , Procedimentos Endovasculares/métodos , Stents , Acidente Vascular Cerebral/cirurgia , Idoso , Idoso de 80 Anos ou mais , Remoção de Dispositivo/efeitos adversos , Feminino , Humanos , Complicações Intraoperatórias/epidemiologia , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/epidemiologia , Estudos Prospectivos , Trombectomia/efeitos adversos , Tomografia Computadorizada por Raios X , Resultado do Tratamento
2.
Nanotechnology ; 19(18): 185709, 2008 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-21825705

RESUMO

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.
Artigo em Inglês | MEDLINE | ID: mdl-15680285

RESUMO

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.


Assuntos
Biofísica/métodos , Transporte Biológico , Difusão , Relação Dose-Resposta a Droga , Etanol/química , Processamento de Imagem Assistida por Computador , Interferometria , Lasers , Membranas Artificiais , Modelos Estatísticos , Modelos Teóricos , Distribuição Normal , Software , Termodinâmica , Fatores de Tempo
4.
J Dermatolog Treat ; 15(6): 379-86, 2004 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-15764050

RESUMO

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).


Assuntos
Terapia por Ultrassom , Úlcera Varicosa/terapia , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
5.
Gen Physiol Biophys ; 21(2): 115-46, 2002 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-12236542

RESUMO

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.


Assuntos
Amônia/química , Celulose/análogos & derivados , Celulose/química , Eletrólitos/química , Membranas Artificiais , Modelos Químicos , Cloreto de Potássio/química , Simulação por Computador , Difusão , Eletroquímica , Gravitação , Osmose , Pressão Osmótica , Polímeros/química , Reprodutibilidade dos Testes , Reologia/métodos , Sensibilidade e Especificidade , Soluções , Termodinâmica , Água/química
6.
Polim Med ; 31(1-2): 45-52, 2001.
Artigo em Polonês | MEDLINE | ID: mdl-11712202

RESUMO

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.


Assuntos
Membranas Artificiais , Modelos Biológicos , Soluções/química , Membrana Celular/metabolismo , Difusão , Solução Hipertônica de Glucose/química , Gravitação , Osmose , Permeabilidade , Polímeros , Pressão , Água/química
7.
Polim Med ; 31(3-4): 25-32, 2001.
Artigo em Polonês | MEDLINE | ID: mdl-11935936

RESUMO

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.


Assuntos
Membranas Artificiais , Modelos Biológicos , Pressão Osmótica , Soluções/química , Difusão , Gravitação , Osmose , Permeabilidade , Polímeros , Propriedades de Superfície
8.
Polim Med ; 31(3-4): 33-41, 2001.
Artigo em Polonês | MEDLINE | ID: mdl-11935938

RESUMO

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.


Assuntos
Membranas Artificiais , Modelos Biológicos , Pressão Osmótica , Soluções/química , Difusão , Etanol/química , Solução Hipertônica de Glucose/química , Gravitação , Osmose , Permeabilidade , Polímeros , Propriedades de Superfície
9.
Polim Med ; 31(3-4): 42-51, 2001.
Artigo em Polonês | MEDLINE | ID: mdl-11935939

RESUMO

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.


Assuntos
Membranas Artificiais , Modelos Biológicos , Pressão Osmótica , Soluções/química , Difusão , Etanol/química , Solução Hipertônica de Glucose/química , Gravitação , Osmose , Permeabilidade , Polímeros , Propriedades de Superfície
10.
Polim Med ; 30(1-2): 21-44, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-11064886

RESUMO

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.


Assuntos
Eletrólitos/química , Gravitação , Membranas Artificiais , Modelos Biológicos , Osmose , Polímeros , Amônia/química , Membrana Celular/metabolismo , Difusão , Eletrólitos/metabolismo , Permeabilidade , Cloreto de Potássio/química , Reologia , Soluções/química , Soluções/metabolismo , Termodinâmica
11.
J Biol Phys ; 26(2): 149-70, 2000 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23345718

RESUMO

In this paper the classification ofthe gravitational effects in a passive transmembranetransport is presented. Among these effects there arethe flux and force gravitational effects (fluxgraviosmotic effect, osmotic pressure graviosmoticeffect, flux gravidiffusive effect, osmotic pressuregravidiffusive effect, voltage gravielectric effectand current gravielectric effect). The volume fluxgraviosmotic and solute flux gravidiffusive effectsmodel equations for a single-membrane system areelaborated. These models for binary and ternarynon-electrolyte solutions have been verified using anexperimental data volume and solute fluxes forosmotic-diffusion cell with horizontally mountedmembrane. In the experimental set-up, water was placedon one side of the membrane. The opposite side of themembrane was exposed to binary or ternary solutions ofdensities greater than that of water (aqueous glucoseor glucose-0.2 mole/l aqueous ethanol) and binary andternary solutions of densities larger than that ofwater (aqueous ethanol or ethanol-0.05 mole/l aqueousglucose). These experimental results are interpretedin terms of the convective instability that increasesthe diffusive permeability coefficient of junction:boundary layer/membrane/boundary layer.

12.
J Biol Phys ; 26(3): 235-54, 2000 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23345724

RESUMO

The solute flows were studied in a double-membrane osmotic-diffusive cell, in which two membranes mounted in horizontal planes separate three compartments (l,m,r) containing the non-homogeneous, non-electrolytic binary and ternary solutions. The volume of inter-membrane compartment (m), which is the infinitesimally layer of solution, and volume of external compartments (l and r) fulfill the conditions V(m)→ 0 and V(l) =V(r)→ ∞, respectively. In an initial moment, the solution concentrations satisfy the condition (C(o) (s))(l) < (C(o) (s))(m) >(C(o) (s))(r). The double-membrane osmotic-diffusive cell is composed of two complexes: boundary layer/membrane/boundary layer, mounted in horizontal planes. In the cell, solute flux was measured as a function of concentration and gravitational configuration. The linear dependencies of the solute flux on concentration difference in binary solutions and nonlinear - in ternary solutions were obtained. It was shown that the double-membrane osmotic-diffusive cell has rectifying and amplifying properties of solute flows.

13.
J Biol Phys ; 25(4): 289-308, 1999 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23345704

RESUMO

Non-equilibrium thermodynamic model equations for non-ionic and heterogeneous n-component solution transport in a m-membrane system are presented. This model is based on two equations. The first one describes the volume transport of the solution and the second the transport of the solute. Definitions of the hydraulic permeability, reflection and diffusive permeability coefficients of the m-membrane system and relations between the coefficients of the m-membrane system and the respective membranes of the system are also given. The validity of this model for binary and ternary solutions was verified, using a double-membrane cell with a horizontally mounted membrane. In the cell, volume and solute fluxes were measured as a function of concentration and gravitational configuration.

14.
Polim Med ; 28(3-4): 3-10, 1998.
Artigo em Polonês | MEDLINE | ID: mdl-10093152

RESUMO

In order to determine of the osmotic-diffusive properties of membranous dressing Bioprocess, which is a microfibrous network of homogeneous cellulose produced in biosynthesis by Acetobacter, the hydraulic permeability (Lp), reflection (sigma) and diffusive permeability (omega) coefficients were measured. The values of these coefficients showed that this membrane possess a low selectivity. This amount it easy permeable for solvent (water) as well as for solutions (aqueous solutions of glucose, sucrose, ethanol, NaCl or KCl). Thus, it attend a demands make for polymeric materials used in therapy of scald and ulceration.


Assuntos
Materiais Biocompatíveis , Celulose , Teste de Materiais , Membranas Artificiais , Curativos Oclusivos , Acetobacter/metabolismo , Celulose/biossíntese , Difusão , Etanol/química , Osmose , Permeabilidade , Polímeros , Soluções/química , Água/química
15.
Polim Med ; 28(3-4): 11-22, 1998.
Artigo em Polonês | MEDLINE | ID: mdl-10093153

RESUMO

A method of determination critical value of concentration Rayleigh Number ((Rci)lim.) in isothermal membrane transport processes of three component non-electrolyte solutions was worked out. The method based on the derived in the paper equation, which include membrane transport coefficients (hydraulic permeability, reflection and diffusive permeability coefficients), solution parameters (viscosity coefficient, density and diffusion coefficient in solution). In order to experimental verification of these method the transport coefficients of symmetric flat polymeric membrane, parameters of solutions and diffusive flux for glucose solution in 0.2 mole/l aqueous ethanol solution were determined. Experiments were carried out by osmotic-diffusive single-membrane double-cell system. One cell in all experiments was filled with pure water while the other with the examined solutions. The experimental critical value of concentration Rayleigh Number (RCi)lim. = 1799 is comparable with theoretical critical value of thermal Rayleigh Number (TT)lim. = 1707.


Assuntos
Membranas Artificiais , Modelos Biológicos , Polímeros , Soluções/química , Difusão , Modelos Estatísticos , Permeabilidade
16.
Polim Med ; 28(3-4): 23-35, 1998.
Artigo em Polonês | MEDLINE | ID: mdl-10093154

RESUMO

In this paper the classification of the gravitational effects in a passive transmembrane transport is presented. Among these effects there are the flux (flux graviosmotic effect, flux gravidiffusive, current gravielectric effect) and force (pressure graviosmotic effect, pressure gravidiffusive effect, voltage gravielectric effect) gravitational effects. The pressure graviosmotic effect model equation in a single-membrane system is elaborated. In this system the flat, microporous and symmetric polymeric membrane (Nephrophan) positioned horizontally separated water and binary (aqueous glucose) or ternary (glucose-0.2 mole/l) aqueous ethanol) non-electrolyte solutions. The calculations of pressure graviosmotic effects for two (A and B) configurations of the single-membrane system were elaborated. In configuration A solution was placed in compartment below membrane and in configuration B--above membrane. These calculated results are interpreted in terms of the convective instability that increases the diffusive permeability coefficient of complex: boundary layer/membrane/boundary layer.


Assuntos
Membranas Artificiais , Modelos Biológicos , Polímeros , Soluções/química , Difusão , Gravitação , Teste de Materiais , Permeabilidade , Pressão
17.
J Biol Phys ; 24(1): 59-78, 1998 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23345669

RESUMO

The volume flows model equation for a double-membrane system, in which two membranes separate three compartments (l,m,r) containing the heterogeneous, non-ionic n-component solutions is elaborated. In this system the solution concentrations fulfill the condition Clk > Cmk > Crk. The inter-membrane compartment (m) consists of the infinitesimal layer of solution. The volume of compartment m and external compartments (l and r) fulfill the conditions Vm→ 0 and Vl =Vr→∞ respectively. The linear dependences of the volume flux on concentration differences in binary solutions and nonlinear - in ternary solutions, were obtained. This model for binary and ternary non-electrolyte solutions is discussed. It is shown, that the double-membrane system has rectifying and amplifying properties for osmotic transport and mechanical pressure.

18.
J Biol Phys ; 23(4): 239-50, 1997 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23345665

RESUMO

This paper presents the physical interpretation of phenomenologicalcoefficients of transmembrane transport for single and neutral membrane andmulticomponent non-ionic solutions. In the framework of this model theexpressions linking the permeability parameters of the membrane(L(p), σ, ω(ik)) with friction coefficients(f(ik)) for n-component, binary and ternary solutions and themethod of calculation of friction coefficients for binary and ternarynon-electrolytes are also presented.

19.
Biophys Chem ; 44(3): 139-42, 1992 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-1420944

RESUMO

The Spiegler-Kedem-Katchalsky frictional model equations of the transmembrane transport for systems containing n-component, non-ionic solutions is presented. The frictional interpretation of the phenomenological coefficients of membrane and the expressions connecting the practical coefficients (Lp, sigma i, omega ij) with frictional coefficients (fij) are presented.


Assuntos
Membranas/metabolismo , Modelos Biológicos , Transporte Biológico , Matemática , Soluções
20.
Biophys Chem ; 38(3): 189-99, 1990 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17056440

RESUMO

The gravielectric effect model equation for a single-membrane system was elaborated. This model for binary and ternary ionic solutions was verified using a cell with a horizontally mounted membrane. In this cell, the membrane and transition potentials were measured as a function of gravitational configuration. In these experiments, a 0.001 M aqueous solution of sodium chloride was placed on one side of the membrane. The opposite side of the membrane was exposed to either aqueous sodium chloride solutions, with densities greater than that of 0.001 M aqueous NaCl, or ethanol/NaCl/water solutions. On the basis of the experimental results, the influence of constrained release and the gravielectric effect were established. These experimental findings are interpreted in terms of a convective gravitational instability that reduces boundary layer dimensions and increases the permeability coefficient of the complex system: boundary layer/membrane/boundary layer. A concentration-gradient Rayleigh number is used in a mathematical model for gravitationally sensitive membrane potential.

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