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1.
Trials ; 24(1): 67, 2023 Jan 29.
Artículo en Inglés | MEDLINE | ID: mdl-36710355

RESUMEN

BACKGROUND: The double-lumen tube (DLT) is an essential equipment for thoracic anesthesia and the precise position of DLT placement is particularly important for anesthesia and surgery. However, the incidence of DLT malposition remains high and it leads to lung isolation failure and hypoxemia during one-lung ventilation. This trial aims to explore the clinical application and efficacy of intubation in the lateral position under general anesthesia induction to reduce the incidence of DLT malposition in patients undergoing unilateral video-assisted thoracic surgery (VATS). METHODS: In this prospective, single-center, parallel group, randomized, controlled trial, we will recruit 108 patients, aged 18-80 years, scheduled for elective unilateral VATS with DLT intubation under general anesthesia, and they will be randomly assigned to two groups: a lateral DLT intubation group (group L) and a conventional supine DLT intubation group (group C). The left-sided DLT will be used to intubate in patients of both groups. The position of DLT will be confirmed and adjusted by using the fiberoptic bronchoscopy (FOB). The primary outcome is the incidence of DLT malposition observed via the FOB, and the secondary outcomes include the time of intubation, the frequency and duration of re-adjustments of DLT placement under FOB, whether to re-intubate, intraoperative vital signs, and postoperative recovery. DISCUSSION: Accurate DLT positioning is crucially important for thoracic surgery, but the incidence of DLT malposition is still high in the present clinical practice of thoracic anesthesia. This trial aims to investigate whether lateral DLT intubation can reduce the incidence of DLT malposition, with more stable intraoperative vital signs and less postoperative complications. TRIAL REGISTRATION: The study protocol was registered at Chinese Clinical Trial Registry ( http://www.chictr.org.cn ) with registration number: ChiCTR2200060794 on June 11, 2022.


Asunto(s)
Intubación Intratraqueal , Cirugía Torácica Asistida por Video , Humanos , Anestesia General , Broncoscopía , Estudios Prospectivos , Ensayos Clínicos Controlados Aleatorios como Asunto , Cirugía Torácica Asistida por Video/efectos adversos , Cirugía Torácica Asistida por Video/métodos , Adolescente , Adulto Joven , Adulto , Persona de Mediana Edad , Anciano , Anciano de 80 o más Años
2.
Nanoscale ; 13(2): 810-818, 2021 Jan 21.
Artículo en Inglés | MEDLINE | ID: mdl-33351010

RESUMEN

Exploring highly effective and low-cost non-noble metal-based electrocatalysts for oxygen evolution reaction (OER) is critical for renewable energy conversion and metal-air batteries. Herein, a novel and high-efficient OER catalyst was reported with nitrogen-doped oxide/sulfide heterostructures (named N-NiCo2S4/CoO microsphere). The N-NiCo2S4/CoO microsphere was synthesized by annealing NiCo-BTC MOF to a multi-layered hollow structure of NiCo2O4 microspheres, followed by the direct vulcanization in the presence of NH4HCO3, resulting in an oxide/sulfide heterojunction. Benefiting from the nitrogen doping, the abundant multi-layered hollow heterostructure and the interfaces between multiple components, the N-NiCo2S4/CoO microsphere exhibited excellent OER activity with a low overpotential of 227 mV at 10 mA cm-2. The Zn-air battery based on the N-NiCo2S4/CoO + Pt/C catalyst displayed excellent cycling stability after 900 cycles at a large current density of 5 mA cm-2, where the commercial RuO2 + Pt/C-based battery exhibited a big drop after only 30 cycles, suggesting its great application prospects as power source devices.

3.
ChemSusChem ; 13(19): 5239-5247, 2020 Oct 07.
Artículo en Inglés | MEDLINE | ID: mdl-32667734

RESUMEN

A rational design is reported of Fe-doped cobalt telluride nanoparticles encapsulated in nitrogen-doped carbon nanotube frameworks (Fe-Co1.11 Te2 @NCNTF) by tellurization of Fe-etched ZIF-67 under a mixed H2 /Ar atmosphere. Fe-doping was able to effectively modulate the electronic structure of Co1.11 Te2 , increase the reaction activity, and further improve the electrochemical performance. The optimized electrocatalyst exhibited superior hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) performances in an alkaline electrolyte with low overpotentials of 107 and 297 mV with a current density of 10 mA cm-2 , in contrast to the undoped Co1.11 Te2 @NCNTF (165 and 360 mV, respectively). The overall water splitting performance only required a voltage of 1.61 V to drive a current density of 10 mA cm-2 . Density function theory (DFT) calculations indicated that the Fe-doping not only afforded abundant exposed active sites but also decreased the hydrogen binding free energy. This work provided a feasible way to study non-precious-metal catalysts for an efficient overall water splitting.

4.
Int J Pharm ; 538(1-2): 65-78, 2018 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-29341908

RESUMEN

Au-methotrexate (Au-MTX) conjugates induced by sugar molecules were produced by a simple, one-pot, hydrothermal growth method. Herein, the Au(III)-MTX complexes were used as the precursors to form Au-MTX conjugates. Addition of different types of sugar molecules with abundant hydroxyl groups resulted in the formation of Au-MTX conjugates featuring distinct characteristics that could be explained by the diverse capping mechanisms of sugar molecules. That is, the instant-capping mechanism of glucose favored the generation of peanut-like Au-MTX conjugates with high colloidal stability while the post-capping mechanism of dextran and sucrose resulted in the production of Au-MTX conjugates featuring excellent near-infrared (NIR) optical properties with a long-wavelength plasmon resonance near 630-760 nm. Moreover, in vitro bioassays showed that cancer cell viabilities upon incubation with free MTX, Au-MTX conjugates doped with glucose, dextran and sucrose for 48 h were 74.6%, 55.0%, 62.0%, and 63.1%, respectively. Glucose-doped Au-MTX conjugates exhibited a higher anticancer activity than those doped with dextran and sucrose, therefore potentially presenting a promising treatment platform for anticancer therapy. Based on the present study, this work may provide the first example of using biocompatible sugars as regulating agents to effectively guide the shape and assembly behavior of Au-MTX conjugates. Potentially, the synergistic strategy of drug molecules and sugar molecules may offer the possibility to create more gold-based nanocarriers with new shapes and beneficial features for advanced anticancer therapy.


Asunto(s)
Antimetabolitos Antineoplásicos/administración & dosificación , Sistemas de Liberación de Medicamentos , Oro/química , Metotrexato/administración & dosificación , Antimetabolitos Antineoplásicos/química , Antimetabolitos Antineoplásicos/farmacología , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Química Farmacéutica/métodos , Dextranos/química , Portadores de Fármacos/química , Glucosa/química , Humanos , Metotrexato/química , Metotrexato/farmacología , Sacarosa/química , Resonancia por Plasmón de Superficie , Factores de Tiempo
5.
Sci Rep ; 6: 32402, 2016 08 30.
Artículo en Inglés | MEDLINE | ID: mdl-27573057

RESUMEN

Elaborate architectural manipulation of nanohybrids with multi-components into controllable 3D hierarchical structures is of great significance for both fundamental scientific interest and realization of various functionalities, yet remains a great challenge because different materials with distinct physical/chemical properties could hardly be incorporated simultaneously into the synthesis process. Here, we develop a novel one-pot cyanogel-bridged synthetic approach for the generation of 3D flower-like metal/Prussian blue analogue nanohybrids, namely PdCo/Pd-hexacyanocobaltate for the first time. The judicious introduction of polyethylene glycol (PEG) and the formation of cyanogel are prerequisite for the successful fabrication of such fascinating hierarchical nanostructures. Due to the unique 3D hierarchical structure and the synergistic effect between hybrid components, the as-prepared hybrid nanoflowers exhibit a remarkable catalytic activity and durability toward the reduction of Rhodamine B (RhB) by NaBH4. We expect that the obtained hybrid nanoflowers may hold great promises in water remediation field and beyond. Furthermore, the facile synthetic strategy presented here for synthesizing functional hybrid materials can be extendable for the synthesis of various functional hybrid nanomaterials owing to its versatility and feasibility.

6.
Sci Rep ; 5: 13703, 2015 Sep 02.
Artículo en Inglés | MEDLINE | ID: mdl-26329555

RESUMEN

Polyhedral noble-metal nanocrystals have received much attention and wide applications as electrical and optical devices as well as catalysts. In this work, a straightforward and effective hydrothermal route for the controllable synthesis of the high-quality Pd-Ag alloy polyhedrons with uniform size is presented. The morphology, composition and structure of the Pd-Ag alloy polyhedrons are fully characterized by the various physical techniques, demonstrating the Pd-Ag alloy polyhedrons are highly alloying. The formation/growth mechanisms of the Pd-Ag alloy polyhedrons are explored and discussed based on the experimental observations and discussions. As a preliminary electrochemical application, the Pd-Ag alloy polyhedrons are applied in the formic acid oxidation reaction, which shows higher electrocatalytic activity and stability than commercially available Pd black due to the "synergistic effects" between Pd and Ag atoms.

7.
Nature ; 520(7548): 518-21, 2015 Apr 23.
Artículo en Inglés | MEDLINE | ID: mdl-25822792

RESUMEN

Most molecular clouds are filamentary or elongated. For those forming low-mass stars (<8 solar masses), the competition between self-gravity and turbulent pressure along the dynamically dominant intercloud magnetic field (10 to 100 parsecs) shapes the clouds to be elongated either perpendicularly or parallel to the fields. A recent study also suggested that on the scales of 0.1 to 0.01 parsecs, such fields are dynamically important within cloud cores forming massive stars (>8 solar masses). But whether the core field morphologies are inherited from the intercloud medium or governed by cloud turbulence is unknown, as is the effect of magnetic fields on cloud fragmentation at scales of 10 to 0.1 parsecs. Here we report magnetic-field maps inferred from polarimetric observations of NGC 6334, a region forming massive stars, on the 100 to 0.01 parsec scale. NGC 6334 hosts young star-forming sites where fields are not severely affected by stellar feedback, and their directions do not change much over the entire scale range. This means that the fields are dynamically important. The ordered fields lead to a self-similar gas fragmentation: at all scales, there exist elongated gas structures nearly perpendicular to the fields. Many gas elongations have density peaks near the ends, which symmetrically pinch the fields. The field strength is proportional to the 0.4th power of the density, which is an indication of anisotropic gas contractions along the field. We conclude that magnetic fields have a crucial role in the fragmentation of NGC 6334.

8.
ACS Appl Mater Interfaces ; 6(24): 22790-5, 2014 Dec 24.
Artículo en Inglés | MEDLINE | ID: mdl-25469763

RESUMEN

Noble metallic nanocrystals (NMNCs) with highly branched morphologies are an exciting new class of nanomaterials because of their great potential application in catalysis, sensing, optics, and electronics originating from their unique structures. Herein, we report a facile water-based method to synthesize high-quality palladium (Pd) tetrapods with the assistance of arginine molecule, which is more economical and environmentally friendly than the previous reported carbon monoxide (CO)-assisted synthesis in the organic system. During the synthesis, arginine molecule plays an essential role in controlling the tetrapod-like morphology. The as-synthesized Pd tetrapods have a potential application in the formic acid (HCOOH)-induced reduction of highly toxic hexavalent chromium (Cr(VI)) owing to their improved catalytic performance for the HCOOH decomposition.

9.
Nature ; 514(7524): 600-2, 2014 Oct 30.
Artículo en Inglés | MEDLINE | ID: mdl-25355359

RESUMEN

The formation of planets around binary stars may be more difficult than around single stars. In a close binary star (with a separation of less than a hundred astronomical units), theory predicts the presence of circumstellar disks around each star, and an outer circumbinary disk surrounding a gravitationally cleared inner cavity around the stars. Given that the inner disks are depleted by accretion onto the stars on timescales of a few thousand years, any replenishing material must be transferred from the outer reservoir to fuel planet formation (which occurs on timescales of about one million years). Gas flowing through disk cavities has been detected in single star systems. A circumbinary disk was discovered around the young low-mass binary system GG Tau A (ref. 7), which has recently been shown to be a hierarchical triple system. It has one large inner disk around the single star, GG Tau Aa, and shows small amounts of shocked hydrogen gas residing within the central cavity, but other than a single weak detection, the distribution of cold gas in this cavity or in any other binary or multiple star system has not hitherto been determined. Here we report imaging of gas fragments emitting radiation characteristic of carbon monoxide within the GG Tau A cavity. From the kinematics we conclude that the flow appears capable of sustaining the inner disk (around GG Tau Aa) beyond the accretion lifetime, leaving time for planet formation to occur there. These results show the complexity of planet formation around multiple stars and confirm the general picture predicted by numerical simulations.

10.
Nanoscale ; 6(21): 12310-4, 2014 Nov 07.
Artículo en Inglés | MEDLINE | ID: mdl-25169420

RESUMEN

The high-quality Pt48Ag52 alloy nano-octahedra are synthesized via one-pot hydrothermal method. The catalytic growth of Ag(0) atoms on Pt nuclei and selective oxidative etching on the Ag(0) atoms contribute to the formation of alloy nano-octahedra. Pt48Ag52 alloy nano-octahedra show excellent electrocatalytic activity and durability for the methanol oxidation reaction (MOR).

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