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1.
Rev. otorrinolaringol. cir. cabeza cuello ; 83(3): 263-266, 2023. graf
Article Dans Espagnol | LILACS | ID: biblio-1522104

Résumé

La terapia de rehabilitación vestibular es el tratamiento con mayor evidencia en la recuperación para la mayoría de los trastornos de equilibrio. En los casos que presentan una alteración estable del procesamiento central del equilibrio, o mixta, es decir, acompañada de una alteración a nivel del sistema nervioso periférico, la terapia de rehabilitación vestibular no se excluye como tratamiento. No obstante, los progresos suelen ser limitados y requieren de una mayor cantidad de sesiones. En este trabajo analizaremos un caso mixto, un paciente con síndrome de núcleo fastigial y el vértigo posicional paroxístico benigno (VPPB), desde la pesquisa y evaluación hasta el tratamiento y alta, en el Hospital Clínico Universidad de Chile.


Vestibular rehabilitation therapy is the treatment with the greatest evidence of recovery for most balance disorders. In the cases that have a loss of central balance processing, or mixed, that is, stable accompanied by a disorder of the peripheral nervous system the vestibular rehabilitation therapy is not excluded as a treatment; however, progress is usually limited and requires a greater number of sessions. In this work we will analyse a mixed case, a patient with nucleus fastigial syndrome and a benign paroxysmal positional vertigo, from the investigation and evaluation to the treatment and discharge, at the Hospital Clínico Universidad de Chile.


Sujets)
Humains , Mâle , Adulte , Maladies vestibulaires/rééducation et réadaptation , Réflexe vestibulo-oculaire , Vertige/rééducation et réadaptation , Sensation vertigineuse/rééducation et réadaptation , Équilibre postural
2.
Chinese Journal of Medical Instrumentation ; (6): 34-37, 2022.
Article Dans Chinois | WPRIM | ID: wpr-928853

Résumé

A biphasic hyperbaric injector based on BLDC is designed for alternate and mixed injection of contrast medium and normal saline in the process of contrast medium injection in hospital. The driver hardware and algorithm are optimized especially for high-pressure and high-speed injection requirements. The interface APP is designed with parameter-input and real-time pressure-plotting of injector's ports as two main functions. The whole device can realize the preset function and has high stability after testing.


Sujets)
Produits de contraste , Injections
4.
Journal of China Pharmaceutical University ; (6): 433-440, 2018.
Article Dans Chinois | WPRIM | ID: wpr-811741

Résumé

@#A sandwiched electrochemical immunoassay based on the AuNPs@GSH-CdTe as a signal label, which formed by GSH-CdTe QDs and AuNPs, with dual signal amplified by reduced graphene oxide and AuNPs was proposed for the sensitive detection of prostate specific antigen(PSA). Through a sandwich immunoreaction, the target PSA and AuNPs@GSH-CdTe labeled Ab1 were captured to rGO/AuNPs-Ab2 surface. After the HNO3-dissolution step, square wave stripping voltammetry(SWSV)analysis of the captured CdTe QDs was used to quantify the concentration of PSA. In this system, AuNPs possessedlarge specific surface and good biocompatibility, which could effectively expand the amount of antigen and GSH-CdTe QDs loading and signals amplifying, while rGO played a synergistic amplification role due to its large specific surface. The proposed method showed good linearity ranging from 0. 5 to 200 ng/mL with the detection limits of 5. 0 pg/mL. It also showed excellent selectivity, good reproducibility, satisfactory stability. In addition, the method was successfully applied to the determination of real samples. The result was satisfactory and the recovery could fall in 98. 20%- 106. 2%, which represented a novel approach for versatile detection of tumor markers.

5.
Journal of Pharmaceutical Analysis ; (6): 55-59, 2018.
Article Dans Chinois | WPRIM | ID: wpr-700353

Résumé

For the first time, sulfanilamide (SFD) was determined in otologic solution, human urine and serum by electroanalytical techniques on glassy carbon electrode (GCE). The cyclic voltammetry (CV) experiments showed an irreversible oxidation peak at +1.06 V in 0.1 mol/L BRBS (pH = 2.0) at 50 mV/s. Different vol-tammetric scan rates (from 10 to 250 mV/s) suggested that the oxidation of SFD on the GCE was a diffusion-controlled process. Square-wave voltammetry (SWV) method under optimized conditions showed a linear response to SFD from 5.0 to 74.7μmol/L (R = 0.999) with detection and quantification limits of 0.92 and 3.10μmol/L, respectively. The developed SWV method showed better results for detection limit and linear range than the chronoamperometry method. It has been successfully applied to determine SFD concentration in pharmaceutical formulation, human urine and serum samples with recovery close to 100%.

6.
Chinese Journal of Analytical Chemistry ; (12): 446-453, 2018.
Article Dans Chinois | WPRIM | ID: wpr-692269

Résumé

A silver nanowires(AgNWs) flexible electrode was prepared using polydimethylsiloxane (PDMS) as the substrate and AgNWs as the conductive layer. It is easier to change the shapes and sizes of the flexible electrode due to its excellent stretchability and foldability. A square wave stripping voltammetry (SWSV) method for the detection of trace copper in water was established using the electrode as the working electrode.The characterization of AgNWs flexible electrode showed that the spread of AgNWs was uniform and the average resistance was 1.03 Ω. The data of electrochemical analysis showed that the properties of the electrode were superior to commercialized gold electrode and silver electrode. The effects of Bi3+concentration, supporting electrolyte,pH value, enrichment potential and enrichment time were determined and optimized. We achieved the sharpest and highest peak of the SWSV curves for the detection of Cu2+in the range of-0.3-0.3 V,which means the most sensitive detection, under the following conditions such as 0.5 mg/L Bi3+,0.1 mol/L support electrolyte tartaric acid-sodium tartrate solution (pH, 4.8), 0.6 V of enrichment potential, and 600 s of enrichment time. Under such conditions, the linear detection range of Cu2+concentration was from 0.001 mg/L to 0.100 mg/L and the detection limit was 9.27×10-5mg/L. The advantages of this detection method are fast speed,high sensitivity and wide detection range. Therefore,it can not only meet the requirements for the copper ion detection but also provide a new method or experimental basis for the detection of other metal ions in water. In addition, the AgNWs flexible electrode has great potential in detections under special circumstances or instantaneous detections due to its wonderful flexibility and biocompatibility.

7.
Chinese Journal of Analytical Chemistry ; (12): 1575-1583, 2016.
Article Dans Chinois | WPRIM | ID: wpr-504396

Résumé

A sumple electrochemucal sensor was constututed based on the glassy carbon electrode ( GCE ) surface modufued wuth nafuon-poly ( duallyldumethylammonuum chlorude ) functuonaluzed graphene sheets ( NA-PDDA-G) composute fulm and herrung sperm double-stranded DNA for durect detectuon of DNA damage un vutro and evaluatuon of the antuoxudant propertues of feruluc acud ( FA) and the aqueous extracts un Angeluca Sunensus (EAS). Scannung electron mucroscopy (SEM) was used to characteruze the morphologues of the fabrucated sensor, whule cycluc voltammetry ( CV ) and electrochemucal umpedance spectroscopy ( EIS ) were used to characteruze the electrochemucal performances of the modufued electrode. Ru ( NH3 ) 3+6 was used as an electroactuve unducator to monutor DNA damage unduced by hydroxyl raducal (?OH ) wuth square wave voltammetry ( SWV ) . The fabrucated sensor showed the greatest degree of DNA oxudatuon damage occurred under the condutuons of 30-mun uncubatuon un Fenton reagent contaunung 1. 0 mmol/L FeSO4 and 5. 0 mmol/L H2O2 at pH 7. 0. The antuoxudant actuvuty of extract un Angeluca Sunensus (EAS) was stronger than that of FA, whule they were all weaker than that of ascorbuc acud ( AA) . The proposed sensor not only exhubuted excellent stabuluty and reproducubuluty, but would be a sumple and novel method for assessment of antuoxudant propertues of meducunal herb components.

8.
Chinese Journal of Analytical Chemistry ; (12): 1395-1401, 2015.
Article Dans Chinois | WPRIM | ID: wpr-481841

Résumé

ZnO nanotubes were prepared via electrospinning the Zn ( AC ) 2-polyacrylonitrile-polyvinylpyrrolidone ( PAN-PVP) precursor, followed by thermal decomposition of the above polymers from the precursor fibers. SEM and XRD characterization confirmed that the as-prepared ZnO nanofibers presented the hollow nanotube form, which was composed of ZnO nanoparticles with the size of about 40 nm in wurtzite crystal structure. By mixing with graphene, the obtained ZnO-graphene composite modified glassy carbon electrode ( ZnO-RGO/GCE ) was successfully constructed by dip-coating, which was used for the determination of Pb2+in water. With the sensitive response of the ZnO-RGO/GC electrode to Pb2+in solution was demonstrated by square wave stripping voltammetry, the response pctential was at -0. 4V. Under the optimized conditions, a good linear relationship between peak current and Pb2+ concentration was obtained in the range of 2. 4×10-9-4. 8×10-7 mol/L (R=0. 9970) by 10 min preconcentration at -1. 0 V in 0. 1 mol/L HAc-NaAc buffer solution (pH=4. 6). The detection limit was 4. 8×10-10 mol/L (S/N>3). The ZnO-RGO/GC electrode had good stability. The practical analytical application of the ZnO-RGO modified electrode was assessed by the measurement of the actual water sample and the result was consistent with that obtained by ICP-MS.

9.
Chinese Journal of Analytical Chemistry ; (12): 985-990, 2014.
Article Dans Chinois | WPRIM | ID: wpr-452472

Résumé

ZnO nanoparticle-containing carbon composite nanofiber ( ZnO-CNF ) was prepared by the electrospinning of the ZnCl2-PAN precursor, followed by preoxidation and carbonization. The ZnO nanoparticles were uniformly distributed on the surface of the carbon nanofiber with the size of 20-30 nm, confirmed by scanning electron microscopy ( SEM ) . The wettability of the ZnO-CNF was studied by water contact angle test. With Nafion as an additive, the ZnO-CNF modified electrode was successfully constructed by dip-coating. The surface morphology and electrochemical properties of the modified electrode were investigated by SEM and cyclic voltammetry. There was a sensitive response of the ZnO-CNF modified electrode on Pb ions in solution, demonstrated by square wave stripping voltammetry. Under the optimized conditions, a good linear relationship between peak current and Pb2+concentration was obtained in the range of 2. 4×10-10-2. 4×10-7 mol/L (R=0. 998) by 10 min preconcentration at -1. 0 V in 0. 1 mol/L NaAc buffer solution (pH=4. 6). The detection limit was 4. 8×10-11 mol/L. The practical analytical application of the ZnO-CNF modified electrode was assessed by the measurement of the actual water sample and the result was consistent with that obtained by ICP-MS.

10.
Chinese Critical Care Medicine ; (12): 722-725, 2014.
Article Dans Chinois | WPRIM | ID: wpr-459017

Résumé

Objective To observe the method of mechanical ventilation in the chest compressions during cardiopulmonary resuscitation (CPR),and to explore the influence of the flow pattern selection of square-wave and decelerating-wave on airway pressure of patients. Methods A prospective self-pairing study was conducted. Forty patients undergoing CPR admitted to Department of Emergency of Lishui City Central Hospital from January 2011 to February 2013 were enrolled. Using Respironics Eisprit ventilator,the working mode and parameters of ventilator were set reasonably according to previous research,while the chest compressions was performed in a stable state by the same doctor,. Each patient received different flow,waves,including square-wave and decelerating-wave,and the highest peak airway pressure was recorded as a pair of data when the time-pressure and time-flow waveform were frozen. Two pairs of data by different doctors were collected in each patient. Eighty pairs of data from 40 patients were collected for statistical analysis by paired t test. Results The highest peak airway pressure of decelerating-wave was (38.15± 5.99)cmH2O (1 cmH2O=0.098 kPa),which was (5.71±1.98)cmH2O lower than that of square wave 〔(43.86± 6.68)cmH2O〕with significantly statistical difference(t=22.010,P=0.000). 73.75%patients undergoing square wave with peak airway pressure over 40 cmH2O were found,but only 45.00% patients were found in decelerating-wave. Conclusion Because decelerating-wave used in mechanical ventilation during CPR can obviously reduce the peak airway pressure,the occurrence of barotrauma,and the probability of triggering high pressure ventilator alarm,and improve the compliance of ventilator,so decelerating-wave is more reasonable than square-wave.

11.
Psychol. neurosci. (Impr.) ; 6(2): 165-178, jul.-dez. 2013. ilus
Article Dans Anglais | LILACS | ID: lil-699233

Résumé

In this study, the on- and off-responses elicited by luminance square wave and sawtooth stimuli at different temporal frequencies and contrasts are described quantitatively. Adding on- and off-responses reveals response asymmetries. Full-field stimuli were produced using a Ganzfeld bowl with arrays of light-emitting diodes (LEDs) as light sources. ERG responses were recorded from six normal subjects. The amplitudes and implicit times of components of the on- and off-responses and the additions were analyzed. The amplitudes of the on-, off- and addition components elicited by square wave stimuli did not depend on temporal frequency with the exception of the late negative components, which decreased with increasing temporal frequency up to 4 Hz. The amplitudes of all components elicited by sawtooth stimuli, except the P-on, decreased with increasing temporal frequency. The amplitude of all components elicited by square wave and sawtooth stimuli were positively correlated with stimulus contrast. The implicit times of the on-components to square wave stimuli and all response components to sawtooth stimuli decreased with increasing temporal frequency. Contrast had an effect on the implicit times of the N-on, P-on, P-off and P-add components elicited by square wave stimuli and the N-on, P-on, P-add and LN-on components elicited by sawtooth stimuli. The asymmetries between on- and off-responses can possibly be used to reveal inner retinal contributions and may therefore be interesting in detecting glaucomatous changes...


Sujets)
Humains , Adulte , Adulte d'âge moyen , Électrorétinographie , Stimulation lumineuse
12.
Braz. j. pharm. sci ; 48(4): 639-649, Oct.-Dec. 2012. ilus, tab
Article Dans Anglais | LILACS | ID: lil-665860

Résumé

A carbon composite electrode modified with copper (II) phosphate immobilized in a polyester resin (Cu3(PO4)2-Poly) for the determination of rutin in pharmaceutical samples by square-wave voltammetry is described herein. The modified electrode allows the determination of rutin at a potential (0.20 V vs. Ag/AgCl (3.0 mol L-1 KCl)) lower than that observed at an unmodified electrode. The peak current was found to be linear to the rutin concentration in the range from 9.9 × 10-8 to 2.5 × 10-6 mol L-1, with a detection limit of 1.2×10-8 mol L-1. The response of the electrode was stable, with no variation in baseline levels within several hours of continuous operation. The surface morphology of the modified electrode was characterized by scanning electron microscopy (SEM) and energy dispersive X-ray (EDX) system. The results obtained are precise and accurate. In addition, these results are in agreement with those obtained by the chromatographic method at a 95% confidence level.


Descreve-se um eletrodo de carbono modificado com fosfato de cobre (II) imobilizado em uma resina de poliéster (Cu3(PO4)2-Poly) para a determinação de rutina em amostras farmacêuticas por voltametria de onda quadrada. O eletrodo modificado permite a determinação de rutina em potencial (0.20 V vs Ag / AgCl (3,0 mol L-1 KCl)) menor que o observado em um eletrodo não modificado. Verificou-se que a corrente de pico foi linear com a concentração de rutina na faixa de 9,9 × 10-8 a 2,5 × 10-6 mol L-1, com um limite de detecção de 1,2 × 10-8 mol L¹. A resposta do eletrodo foi estável, sem variação significativa dentro de várias horas de operação contínua. A morfologia da superfície do eletrodo modificado foi caracterizada por microscopia eletrônica de varredura (MEV) e pelo sistema de energia dispersiva de raios-X (EDX). Os resultados obtidos foram precisos e exatos. Ademais, estes resultados estão de acordo com aqueles obtidos pelo método cromatográfico a um nível de confiança de 95%.


Sujets)
Rutoside/analyse , Chimie pharmaceutique/classification , Électrodes/classification , Microscopie électronique à balayage
13.
Article Dans Anglais | IMSEAR | ID: sea-164218

Résumé

Erythromycin A (EA) is now one of antibiotics limited in seafood products in general and in giant freshwater prawns (Macrobrachium rosenbergii) and tilapia (Oreochromis niloticus) in particular while exporting to the US, EU, Japan, Canada. There are many methods used for analyzing this antibiotic in these aqua species such as ELISA, HPLC, LC-MS/MS, GC-MS, etc. A new sensitive analytical approach for determination of erythromycin A using stripping square wave voltammetry at the slowly dropping mercury electrode was primarily developed and validated to quantify this antibiotic with simple and short time analysis, not too pure analytical solutions, not high price equipments. Electrochemical signals were measured at potential wave -1430 mV. The optimal experimental parameters for the method were: supporting electrolyte ammonium acetate 0.1 M, pH 8.0, the solvents for dissolving erythromycin standard: acetonitril, Vstart = -400 mV, Vstop = -1700 mV, Vstep = 6 mV, Vpulse = 40 mV, Tdrop = 5000 ms , Velctrolise = -1100 mV, Telectrolyse = 5 s. The method showed high recovery (85.07 ÷ 96.50 %), high sensitivity (lower limit of detection, LoD = 0.57 μg kg-1 in giant prawn and LoD = 0.52 μg kg-1 in tilapia) and high precision (RSD 0.91 ÷ 2.1 %) as well as excellent linearity (r2 adjusted ≥ 0.99999).

14.
Korean Journal of Medical Physics ; : 73-80, 2007.
Article Dans Anglais | WPRIM | ID: wpr-107967

Résumé

Fruitful findings have been produced from five out of sixty cells which were obtained from each 63 individual Aplisia caught at the Jeju coast. Spiking patterns of three out of five cells, such as relaxation oscillator, bursting within a short time of the inter-burst interval, chaotic bursting, period doubling sequences, bursting with long trains of action potentials separated by short silent periods, regular repeated beating or elliptic bursting, and silent states had been changed in order as the temperature was lowered to 10 degrees C from 32 degrees C. In the intervals of every about 40 minutes repeated ups and downs of temperature produced similar firing patterns at the allowable temperature ranges. The other two cells showed difference from these. The amplitudes of the action potentials of the two cells will not be highly decreased in 24 hours. Average spike frequencies, the inter-burst interval, peak to peak spike amplitude of action potentials, minimum potential values are compared and analyzed by using the computer programme. The spike frequencies according to temperature show the distribution of bell type, with maximal spike frequencies at intermediate temperatures and minimal ones at either end. The most common pattern consist of high spike frequency during falling and low one during rising temperatures.


Sujets)
Potentiels d'action , Aplysia , Incendies , Fruit , Température élevée , Relaxation
15.
Chinese Medical Equipment Journal ; (6)2004.
Article Dans Chinois | WPRIM | ID: wpr-587099

Résumé

Firstly,this article analyzes the requirement of the standard voltage for the ECG & EEG verification instrument.Then it analyzes the feasibility of measurement using 34401A multimeter and provides the test method.This method is proved to be exact and reliable by experiment.

16.
Korean Journal of Nuclear Medicine ; : 336-343, 2000.
Article Dans Coréen | WPRIM | ID: wpr-84485

Résumé

PURPOSE: Thallous-201 chloride produced at Korea Cancer Center Hospital(KCCH) is used in detecting cardiovascular disease and cancer. Thallium impurity can cause emesis, catharsis and nausea, so the presence of thallium and other metal impurities should be determined. According to USP and KP, their amounts must be less than 2 ppm in thallium and 5 ppm in total. In this study, the detection method of trace amounts of metal impurities in [201Tl]TlCl injection with polarography was optimized without environmental contamination. MATERALS AND METHODS: For the detection of metal impurities, Osteryoung Square Wave Stripping Voltammetry method was used in Bio-Analytical System (BAS) 50W polarograph. The voltammetry was composed of Dropping Mercury Electrode (DME) as a working electrode, Ag/AgCl as a reference electrode and Pt wire as a counter electrode. Square wave stripping method, which makes use of formation and deformation of amalgam, was adopted to determine the metal impurities, and pH 7 phosphate buffer was used as supporting electrolyte. RESULTS: T1, Cu and Pb in thallous-201 chloride solution were detected by scanning from 300 mV to -800 mV. Calibration curves were made by using TlNO3, CuSO4 and Pb(NO3)2 as standard solutions. Tl was confirmed at -450 mV peak potential and Cu at -50 mV. Less than 2 ppm of Tl and Cu was detected and Pb was not detected in KCCH-produced thallous-201 chloride injection. CONCLUSION: Detection limit of thallium and copper is approximately 50 ppb with this method. As a result of this experiment, thallium and other metal impurities in thallous-201 chloride injection, produced at Korea Cancer Center Hospital, are in the regulation of USP and KP. Polarograph could be applied for the determination of metal impurities in the quality control of radiopharmaceuticals conveniently without environmental contamination.


Sujets)
Calibrage , Maladies cardiovasculaires , Catharsis , Cuivre , Électrodes , Concentration en ions d'hydrogène , Corée , Limite de détection , Métaux lourds , Nausée , Polarographie , Contrôle de qualité , Radiopharmaceutiques , Thallium , Vomissement
17.
Chinese Traditional Patent Medicine ; (12)1992.
Article Dans Chinois | WPRIM | ID: wpr-577298

Résumé

AIM:A voltammetric method was developed for the determination of salvianolic acid B using a carbon nanotube paste electrode.And the separation process of salvianolic acid B was detected. METHODS: In Britton-Robinson buffer solution of pH(1.81),the square wave stripping voltammetric method was used to determine salvianolic acid B. RESULTS: The proposed method was verified by an established HPLC method,and it was applied to determining salvianolic acid B in eluent of eluting extracts of Radix salvia Miltiorrhiza from SP-207 colunm with ethanol solution,and the results were satisfied. CONCLUSION: A new method for determining salvianolic acid B was developed,and the proposed method would be used as an on-line quality control method for detecting of salvianolic acid B in eluting extracts of Radix salvia Miltiorrhiza in the future.

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