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1.
Obes Surg ; 34(6): 2186-2197, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38684584

RESUMEN

As bariatric surgeries (BS) increase, more incidental findings are liable to be discovered. Incidental gastric gastrointestinal stromal tumors (GISTs) during BS can be found in around 0.7% of the cases. In this article, we have performed a systematic review of the literature and added our data to those of the review to review a conceptual treatment strategy to both improve patient outcomes and decrease the risk of overall cancer. With the rise of new bariatric techniques, we have proposed a new classification to BS to enhance our description of the treatment strategy.


Asunto(s)
Cirugía Bariátrica , Tumores del Estroma Gastrointestinal , Hallazgos Incidentales , Obesidad Mórbida , Neoplasias Gástricas , Humanos , Tumores del Estroma Gastrointestinal/cirugía , Cirugía Bariátrica/métodos , Neoplasias Gástricas/cirugía , Obesidad Mórbida/cirugía , Femenino , Masculino , Persona de Mediana Edad , Adulto
2.
Nanoscale Res Lett ; 14(1): 143, 2019 Apr 24.
Artículo en Inglés | MEDLINE | ID: mdl-31016416

RESUMEN

We present a synthesis of large-area single-layer graphene on copper substrate using a refined cooking palm oil, a natural single carbon source, by a home-made spray injector-assisted chemical vapor deposition system. The effects of the distance between spray nozzle and substrate, and growth temperature are studied. From Raman mapping analysis, shorter distance of 1 cm and temperature of around 950 °C lead to the growth of large-area single-layer graphene with a coverage up to 97% of the measured area size of 6400 µm2. The crystallinity of the grown single layer graphene is relatively good due to high distribution percentage of FWHM values of 2D band that is below 30 cm-1. However, the defect concentration is relatively high, and it suggests that a flash-cooling technique needs to be introduced.

3.
The Egyptian Journal of Hospital Medicine ; 76(7): 1687-2002, 2019. tab
Artículo en Inglés | AIM (África) | ID: biblio-1272768

RESUMEN

Background: Autism Spectrum Disorder (ASD) is a behaviorally defined complex neurodevelopmental syndrome. ASD is one of the most common child psychiatric disorders. Despite the long history of research on ASD, no much is known yet about the exact biological causes and how the disorder can be effectively treated. Objective: To study clinical effect of repetitive Transcranial Magnetic Stimulation (rTMS) on a sample of children with autism spectrum disorder. Patients and Methods: the sample consisted of 30 children. Their ages ranged from 4 to 10 years old. After being diagnosed clinically according to DSM-5 through a designed semi-structured interview and through application of childhood autistic rating scale CARS and assessment of the degree of clinical severity of autism spectrum disorders according to DSM-5. Results: The results of the study after the completion of 12 sessions of rTMS, there was a significant difference and improvement in the severity of the clinical symptoms for ASD except for the level of activity and listening response and use of the body by comparing the severity of symptoms before and after rTMS. Comparing results before and after rTMS by the level of clinical severity of autism according to DSM-5; at the level of severity in social communication, the improvement was statistically significant (p-value 0.001). At the level of severity in restricted and repetitive behaviors the improvement was statistically highly significant (p-value <0.001). Conclusion: this study concluded that rTMS over left dorso-lateral prefrontal cortex may be safe and effective way of providing a relief of ASD symptoms


Asunto(s)
Trastorno del Espectro Autista , Estimulación Transcraneal de Corriente Directa
4.
Nanoscale Res Lett ; 11(1): 246, 2016 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-27173675

RESUMEN

We demonstrate a systematic computational analysis of the measured optical and charge transport properties of the spray pyrolysis-grown ZnO nanostructures, i.e. nanosphere clusters (NSCs), nanorods (NRs) and nanowires (NWs) for the first time. The calculated absorbance spectra based on the time-dependent density functional theory (TD-DFT) shows very close similarity with the measured behaviours under UV light. The atomic models and energy level diagrams for the grown nanostructures were developed and discussed to explain the structural defects and band gap. The induced stresses in the lattices of ZnO NSCs that formed during the pyrolysis process seem to cause the narrowing of the gap between the energy levels. ZnO NWs and NRs show homogeneous distribution of the LUMO and HOMO orbitals all over the entire heterostructure. Such distribution contributes to the reduction of the band gap down to 2.8 eV, which has been confirmed to be in a good agreement with the experimental results. ZnO NWs and NRs exhibited better emission behaviours under the UV excitation as compared to ZnO NSCs and thin film as their visible range emissions are strongly quenched. Based on the electrochemical impedance measurement, the electrical models and electrostatic potential maps were developed to calculate the electron lifetime and to explain the mobility or diffusion behaviours in the grown nanostructure, respectively.

5.
Nanoscale Res Lett ; 10(1): 452, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26608535

RESUMEN

The evolution of zinc oxide nanostructures grown on graphene by alcohol-assisted ultrasonic spray pyrolysis was investigated. The evolution of structures is strongly depended on pyrolysis parameters, i.e., precursor molarity, precursor flow rate, precursor injection/deposition time, and substrate temperature. Field-effect scanning electron microscope analysis, energy dispersive X-ray spectroscopy, X-ray diffraction, and transmission electron microscopy were used to investigate the properties of the synthesized nanostructures and to provide evidence for the structural changes according to the changes in the pyrolysis parameters. The optimum parameters to achieve maximum density and well-defined hexagonally shaped nanorods were a precursor molarity of 0.2 M, an injection flow rate of 6 ml/min, an injection time of 10 min, and a substrate temperature of 250-355 °C. Based on the experimental results, the response surface methodology (RSM) was used to model and optimize the independent pyrolysis parameters using the Box-Behnken design. Here, the responses, i.e., the nanostructure density, size, and shape factor, are evaluated. All of the computations were performed using the Design-Expert software package. Analysis of variance (ANOVA) was used to evaluate the results of the model and to determine the significant values for the independent pyrolysis parameters. The evolution of zinc oxide (ZnO) structures are well explained by the developed modelling which confirms that RSM is a reliable tool for the modelling and optimization of the pyrolysis parameters and prediction of nanostructure sizes and shapes.

6.
Nanoscale Res Lett ; 10(1): 1008, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26198282

RESUMEN

The dissociation of zinc ions (Zn(2+)) from vapor-phase zinc acetylacetonate, Zn(C5H7O2)2, or Zn(acac)2 and its adsorption onto graphene oxide via atomic layer deposition (ALD) were studied using a quantum mechanics approach. Density functional theory (DFT) was used to obtain an approximate solution to the Schrödinger equation. The graphene oxide cluster model was used to represent the surface of the graphene film after pre-oxidation. In this study, the geometries of reactants, transition states, and products were optimized using the B3LYB/6-31G** level of theory or higher. Furthermore, the relative energies of the various intermediates and products in the gas-phase radical mechanism were calculated at the B3LYP/6-311++G** and MP2/6-311 + G(2df,2p) levels of theory. Additionally, a molecular orbital (MO) analysis was performed for the products of the decomposition of the Zn(acac)2 complex to investigate the dissociation of Zn(2+) and the subsequent adsorption of H atoms on the C5H7O2 cluster to form acetylacetonate enol. The reaction energies were calculated, and the reaction mechanism was accordingly proposed. A simulation of infrared (IR) properties was performed using the same approach to support the proposed mechanism via a complete explanation of bond forming and breaking during each reaction step.

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