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1.
Beilstein J Nanotechnol ; 15: 719-732, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38919168

RESUMEN

A TiO2/graphene quantum dots composite (TiO2/GQDs) obtained by in situ synthesis of GQDs, derived from coffee grounds, and peroxo titanium complexes was used as electrode modifier in the simultaneous electrochemical determination of uric acid and hypoxanthine. The TiO2/GQDs material was characterized by photoluminescence, X-ray diffraction, Raman spectroscopy, high-resolution transmission electron microscopy, and energy-dispersive X-ray mapping. The TiO2/GQDs-GCE exhibits better electrochemical activity for uric acid and hypoxanthine than GQDs/GCE or TiO2/GCE in differential pulse voltammetry (DPV) measurements. Under optimized conditions, the calibration plots were linear in the range from 1.00 to 15.26 µM for both uric acid and hypoxanthine. The limits of detection of this method were 0.58 and 0.68 µM for uric acid and hypoxanthine, respectively. The proposed DPV method was employed to determine uric acid and hypoxanthine in urine samples with acceptable recovery rates.

2.
RSC Adv ; 13(36): 25007-25017, 2023 Aug 21.
Artículo en Inglés | MEDLINE | ID: mdl-37614787

RESUMEN

The electronic, magnetic, optical and elastic properties of nanomaterials are governed partially by the crystallite size and crystal defects. Here, the crystalline size of hexagonal La1-xSrxMnO3 (x = 0.3) nanoparticles was determined using various methods. Single-phase La0.7Sr0.3MnO3 nanopowders were produced after 10 h of milling in a commercial high-energy SPEX 8000D shaker mill, and then they were heated at 700 °C and 800 °C to study the effect of calcined temperature on the crystallization of nanoparticles. The modified Scherrer, Williamson-Hall, size-strain, and Halder-Wagner methods were used to determine the crystallite sizes and the elastic properties, such as intrinsic strain, stress, and energy density, from the X-ray diffraction peak broadening analysis. The obtained results were then compared with one another. The difference in crystallite sizes calculated from the different methods was due to the different techniques.

3.
Pediatr Surg Int ; 39(1): 123, 2023 Feb 14.
Artículo en Inglés | MEDLINE | ID: mdl-36787049

RESUMEN

PURPOSE: Congenital tracheal stenosis is a rare but dangerous disease. Reconstructive tracheal surgery is a life-saving treatment but also a challenging procedure. This study aims to evaluate the outcomes of tracheal reconstruction surgery. METHODS: A prospective cohort study was conducted with all the records of congenital tracheal stenosis which had been managed by tracheal reconstruction surgery at Children's Hospital 2 Ho Chi Minh City from August 2013 to August 2022. RESULTS: Sixty-seven cases, who underwent slide tracheoplasty, were included in our study. Mean age was 7.6 months (25 days - 8 years). Common congenital-associated lesion was left pulmonary artery sling, accounting for 65.7% of cases. Bronchial stenosis was found in 22.4% patients. Emergency surgery was performed in eight cases. The survival rate in this review was 86.6%. Nine patients died in which four of nine cases (44.4%) were emergency surgery. The recurrent stenosis rate was 8.9%, only two cases needed reoperation in which one died and one recovered uneventfully. The outcomes of surgery were good in 53 cases (79.1%). CONCLUSION: Tracheal reconstruction surgery with slide tracheoplasty technique is safe and versatile technique which is feasible in every case of congenital tracheal stenosis. Mortality was associated with severe cases which required emergency surgery.


Asunto(s)
Tráquea , Niño , Humanos , Lactante , Constricción Patológica/cirugía , Estudios Prospectivos , Resultado del Tratamiento , Estudios Retrospectivos , Tráquea/cirugía
4.
PLoS One ; 17(8): e0272423, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35913921

RESUMEN

In this paper, we propose a secure system for performing deep learning with distributed trainers connected to a central parameter server. Our system has the following two distinct features: (1) the distributed trainers can detect malicious activities in the server; (2) the distributed trainers can perform both vertical and horizontal neural network training. In the experiments, we apply our system to medical data including magnetic resonance and X-ray images and obtain approximate or even better area-under-the-curve scores when compared to the existing scores.


Asunto(s)
Aprendizaje Profundo , Computadores , Imagen por Resonancia Magnética/métodos , Redes Neurales de la Computación
5.
N Engl J Med ; 374(2): 124-34, 2016 Jan 14.
Artículo en Inglés | MEDLINE | ID: mdl-26760084

RESUMEN

BACKGROUND: Tuberculous meningitis is often lethal. Early antituberculosis treatment and adjunctive treatment with glucocorticoids improve survival, but nearly one third of patients with the condition still die. We hypothesized that intensified antituberculosis treatment would enhance the killing of intracerebral Mycobacterium tuberculosis organisms and decrease the rate of death among patients. METHODS: We performed a randomized, double-blind, placebo-controlled trial involving human immunodeficiency virus (HIV)-infected adults and HIV-uninfected adults with a clinical diagnosis of tuberculous meningitis who were admitted to one of two Vietnamese hospitals. We compared a standard, 9-month antituberculosis regimen (which included 10 mg of rifampin per kilogram of body weight per day) with an intensified regimen that included higher-dose rifampin (15 mg per kilogram per day) and levofloxacin (20 mg per kilogram per day) for the first 8 weeks of treatment. The primary outcome was death by 9 months after randomization. RESULTS: A total of 817 patients (349 of whom were HIV-infected) were enrolled; 409 were randomly assigned to receive the standard regimen, and 408 were assigned to receive intensified treatment. During the 9 months of follow-up, 113 patients in the intensified-treatment group and 114 patients in the standard-treatment group died (hazard ratio, 0.94; 95% confidence interval, 0.73 to 1.22; P=0.66). There was no evidence of a significant differential effect of intensified treatment in the overall population or in any of the subgroups, with the possible exception of patients infected with isoniazid-resistant M. tuberculosis. There were also no significant differences in secondary outcomes between the treatment groups. The overall number of adverse events leading to treatment interruption did not differ significantly between the treatment groups (64 events in the standard-treatment group and 95 events in the intensified-treatment group, P=0.08). CONCLUSIONS: Intensified antituberculosis treatment was not associated with a higher rate of survival among patients with tuberculous meningitis than standard treatment. (Funded by the Wellcome Trust and the Li Ka Shing Foundation; Current Controlled Trials number, ISRCTN61649292.).


Asunto(s)
Infecciones Oportunistas Relacionadas con el SIDA/tratamiento farmacológico , Antituberculosos/administración & dosificación , Levofloxacino/administración & dosificación , Rifampin/administración & dosificación , Tuberculosis Meníngea/tratamiento farmacológico , Adulto , Antituberculosos/efectos adversos , Método Doble Ciego , Farmacorresistencia Bacteriana , Quimioterapia Combinada , Femenino , Infecciones por VIH/complicaciones , Humanos , Estimación de Kaplan-Meier , Levofloxacino/efectos adversos , Masculino , Persona de Mediana Edad , Mycobacterium tuberculosis/efectos de los fármacos , Modelos de Riesgos Proporcionales , Rifampin/efectos adversos , Tuberculosis Meníngea/complicaciones , Tuberculosis Meníngea/mortalidad
6.
Food Nutr Bull ; 36(4): 441-54, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26578534

RESUMEN

BACKGROUND: In 2005, more than 90% of Vietnamese households were using adequately iodized salt, and urinary iodine concentration among women of reproductive age was in the optimal range. However, household coverage declined thereafter to 45% in 2011, and urinary iodine concentration levels indicated inadequate iodine intake. OBJECTIVE: To review the strengths and weaknesses of the Vietnamese universal salt iodization program from its inception to the current day and to discuss why achievements made by 2005 were not sustained. METHODS: Qualitative review of program documents and semistructured interviews with national stakeholders. RESULTS: National legislation for mandatory salt iodization was revoked in 2005, and the political importance of the program was downgraded with consequential effects on budget, staff, and authority. CONCLUSIONS: The Vietnamese salt iodization program, as it was initially designed and implemented, was unsustainable, as salt iodization was not practiced as an industry norm but as a government-funded activity. An effective and sustainable salt iodization program needs to be reestablished for the long-term elimination of iodine deficiency, building upon lessons learned from the past and programs in neighboring countries. The new program will need to include mandatory legislation, including salt for food processing; industry responsibility for the cost of fortificant; government commitment for enforcement through routine food control systems and monitoring of iodine status through existing health/nutrition assessments; and intersectoral collaboration and management of the program. Many of the lessons would apply equally to universal salt iodization programs in other countries and indeed to food fortification programs in general.


Asunto(s)
Alimentos Fortificados/historia , Programas de Gobierno/historia , Yodo/historia , Evaluación de Programas y Proyectos de Salud , Cloruro de Sodio Dietético/historia , Femenino , Historia del Siglo XX , Historia del Siglo XXI , Humanos , Yodo/administración & dosificación , Yodo/deficiencia , Yodo/orina , Legislación Alimentaria/historia , Salud Pública , Cloruro de Sodio Dietético/administración & dosificación , Vietnam
7.
J Nanosci Nanotechnol ; 11(3): 2726-9, 2011 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-21449463

RESUMEN

In this study, we successfully synthesized monodisperse magnetite nanoparticles (NPs) (Fe3O4) by sonochemical method using mono (ethylene glycol) (MEG) as a modifier of the reaction environment and found that MEG could be a good candidate to prevent oxidation and toxicity in sonochemical synthesis. The microstructure and size distribution of the Fe3O4 NPs were characterized by X-ray diffraction (XRD) and transmission electron microscopy (TEM) respectively. It revealed that the NPs prepared by MEG assisted sonochemical method show a smaller average size and better monodispersity compared to conventional sonochemical method. Due the the reduced average size and uniform size distribution nature of the NPs, it also showed good superparamagnetic properties with very low coercivity less than 0.5 Oe.


Asunto(s)
Coloides/química , Cristalización/métodos , Glicol de Etileno/química , Glicol de Etileno/efectos de la radiación , Magnetismo , Nanopartículas de Magnetita/química , Nanopartículas de Magnetita/efectos de la radiación , Sonicación/métodos , Titanio/química , Sustancias Macromoleculares/química , Sustancias Macromoleculares/efectos de la radiación , Nanopartículas de Magnetita/ultraestructura , Ensayo de Materiales , Conformación Molecular/efectos de la radiación , Tamaño de la Partícula , Propiedades de Superficie/efectos de la radiación
8.
Chemistry ; 16(10): 3090-6, 2010 Mar 08.
Artículo en Inglés | MEDLINE | ID: mdl-20119993

RESUMEN

Chiral bis(oxazolinylphenyl)amines proved to be efficient auxiliary ligands for iron and cobalt catalysts with high activity for asymmetric hydrosilylation of ketones and asymmetric conjugate hydrosilylation of enones.

9.
Emerg Infect Dis ; 12(12): 1841-7, 2006 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-17326934

RESUMEN

To evaluate risk factors for human infection with influenza A subtype H5N1, we performed a matched case-control study in Vietnam. We enrolled 28 case-patients who had laboratory-confirmed H5N1 infection during 2004 and 106 age-, sex-, and location-matched control-respondents. Data were analyzed by matched-pair analysis and multivariate conditional logistic regression. Factors that were independently associated with H5N1 infection were preparing sick or dead poultry for consumption < or =7 days before illness onset (matched odds ratio [OR] 8.99, 95% confidence interval [CI] 0.98-81.99, p = 0.05), having sick or dead poultry in the household < or =7 days before illness onset (matched OR 4.94, 95% CI 1.21-20.20, p = 0.03), and lack of an indoor water source (matched OR 6.46, 95% CI 1.20-34.81, p = 0.03). Factors not significantly associated with infection were raising healthy poultry, preparing healthy poultry for consumption, and exposure to persons with an acute respiratory illness.


Asunto(s)
Subtipo H5N1 del Virus de la Influenza A/crecimiento & desarrollo , Gripe Humana/virología , Adolescente , Adulto , Animales , Estudios de Casos y Controles , Niño , Preescolar , Femenino , Humanos , Lactante , Gripe Humana/epidemiología , Gripe Humana/transmisión , Modelos Logísticos , Masculino , Aves de Corral , Enfermedades de las Aves de Corral/virología , Factores de Riesgo , Encuestas y Cuestionarios , Vietnam/epidemiología , Zoonosis/transmisión , Zoonosis/virología
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