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1.
Gastrointest Endosc ; 99(6): 989-997, 2024 06.
Artigo em Inglês | MEDLINE | ID: mdl-38101583

RESUMO

BACKGROUND AND AIMS: Hypoxemia is one of the most common adverse events during colonoscopy, particularly among patients who are diagnosed with obstructive sleep apnea (OSA) or are overweight. Consequently, the objective of this study was to evaluate the effectiveness of bilevel positive airway pressure (BPAP) ventilation for patients with high-risk hypoxemia during colonoscopy with sedation. METHODS: In this trial, 127 patients who met the eligibility criteria were randomly assigned to the BPAP oxygen group and nasal cannula (NC) group. The primary endpoint was the incidence of hypoxemia. RESULTS: Compared with the use of NC, BPAP ventilation exhibited a significant reduction in the incidence of hypoxemia, decreasing it from 23.8% to 6.3% (absolute risk difference, 17.5%; 95% confidence interval, 5.4-29.6; P = .006). Importantly, BPAP ventilation prevented the occurrence of severe hypoxemia (9.5% vs 0%; absolute risk difference, 9.5%; 95% confidence interval, 2.3-16.7; P = .035). In addition, the BPAP group required fewer airway interventions (P < .05). CONCLUSIONS: In individuals with OSA or overweight status, the use of BPAP ventilation during colonoscopy significantly reduced the incidence of hypoxemia. (Clinical trial registration number: ChiCTR2300073193.).


Assuntos
Colonoscopia , Hipóxia , Apneia Obstrutiva do Sono , Humanos , Colonoscopia/métodos , Colonoscopia/efeitos adversos , Masculino , Feminino , Pessoa de Meia-Idade , Hipóxia/etiologia , Estudos Prospectivos , Apneia Obstrutiva do Sono/terapia , Idoso , Sedação Consciente/efeitos adversos , Sedação Consciente/métodos , Sobrepeso/complicações , Respiração com Pressão Positiva/métodos , Cânula , Adulto
2.
Small ; 17(1): e2006624, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33284516

RESUMO

The performances of catalysts are highly dependent on their crystallinities. It is a significant challenge to successively manipulate the crystallinities of noble metal nanocatalysts due to the strong metallic bonds, especially under ambient conditions. Herein, a post-crystallization approach is developed for successive control of the crystallinity of Pd nanosheets via selective oxidation etching of the amorphous domains. This strategy can be extended to crystallize other Pd and Ru nanomaterials. By carefully modulating the crystallinity of Pd nanosheets, the time for the complete conversion of 4-nitrostyrene via hydrogenation is reduced by 20 times. Also, crystallization can turn the selectivity of the products and improve the stability of Pd nanosheets. These findings may advance the crystal engineering of metal nanomaterials for wide applications.

3.
Animals (Basel) ; 14(9)2024 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-38731297

RESUMO

To explore the impacts of multiple environmental stressors on animal communities in aquatic ecosystems, we selected protozoa-a highly sensitive group of organisms-to assess the effect of environmental change. To conduct this simulation we conducted a three-factor, outdoor, mesocosm experiment from March to November 2021. Changes in the community structure and functional group composition of protozoan communities under the separate and combined effects of these three environmental stressors were investigated by warming and the addition of nitrogen, phosphorus, and pesticides. The results were as follows: (1) Both eutrophication and pesticides had a considerable promotional effect on the abundance and biomass of protozoa; the effect of warming was not considerable. When warming was combined with eutrophication and pesticides, there was a synergistic effect and antagonistic effect, respectively. (2) Eutrophication promoted α diversity of protozoa and affected their species richness and dominant species composition; the combination of warming and pesticides remarkably reduced the α diversity of protozoa. (3) Warming, eutrophication, and pesticides were important factors affecting the functional groups of protozoa. Interaction among different environmental factors could complicate changes in the aquatic ecological environment and its protozoan communities. Indeed, in the context of climate change, it might be more difficult to predict future trends in the protozoan community. Therefore, our results provide a scientific basis for the protection and restoration of shallow lake ecosystems; they also offer valuable insights in predicting changes in shallow lakes.

4.
Langmuir ; 28(1): 736-40, 2012 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-22074032

RESUMO

Microemulsions are often used in the synthesis of nanoparticles in solution. In this work, we put forward the concept of a "hard microemulsion", which is based on the differential partitioning of water and ethanol solvent molecules inside functional polymer matrices. When the mixture of water and organic solvent enters the functional polymer, the liquid molecules should partition to different regions. Water should concentrate in the microdomains rich in hydrophilic functional groups, forming water-enriched cores, whereas organic solvents should localize near the alkyl polymer skeleton, forming organic liquid enriched outer layers. From a macroscopic view, the swollen polymer matrix is divided into numerous "microdroplets", resembling frozen water-in-oil microemulsions. We define such a structure as a "hard microemulsion". The water-enriched microdroplets may act as templates for synthesizing inorganic nanoparticles. We demonstrate the utility of hard microemulsions for the controllable synthesis of silver and platinum nanoparticles inside different macroreticular functional polymers.

5.
Nutrients ; 14(19)2022 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-36235805

RESUMO

Objective: To explore the effects of breastfeeding during the first four months of life on thinness, overweight, and obesity and to analyze the influential factors in children aged three to six years in eastern China. Methods: This study was designed as a retrospective cohort study, and the Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) guidelines were followed. A total of 8053 subjects were included in this secondary analysis of data from the 2015 "Physical Fitness Surveillance data of Jiangsu, China". The subjects were classified into three groups on the basis of feeding patterns: breastfeeding, mixed feeding, and formula feeding. The International Obesity Task Force (IOTF) definitions of BMI were used to define thinness, overweight, and obesity. Multivariate logistic regression models and subgroup analysis were used to assess the association between feeding patterns and childhood thinness, overweight, obesity, and overweight/obesity, adjusted for potential confounders (sex, age grade, area, region/economy, gestational age, birthweight, childbearing age, mother's education, and caretaker). Results: The prevalence of breastfeeding was 63.8%, and the prevalence of thinness, overweight, obesity, and overweight/obesity reached 2.7%, 11.2%, 4.7%, and 15.9%, respectively. Breastfeeding participants had a lower risk of overweight and overweight/obesity with adjusted ORs of 0.652 (95% CI: 0.533, 0.797; p < 0.001) and 0.721 (95% CI: 0.602, 0.862; p < 0.001), respectively; however, there was no difference in thinness and obesity (both p > 0.05) compared with formula feeding. There was no statistical difference between mixed and formula feeding, in terms of thinness, overweight, obesity, or overweight/obesity (all p > 0.05). Subgroup analysis showed that breastfeeding for three years, preterm, and a childbearing age of 25−29 years had higher adjusted ORs for thinness, and in 5−6 years, urban areas, southern/developed economy regions, post-mature, childbearing age ≥ 25 years, and other caretakers had higher and invalid breastfeeding-adjusted ORs (all p > 0.05 except overweight in the urban grade) for both overweight and overweight/obesity. Conclusions: Breastfeeding during the first four months was not associated with the thinness of children aged 3−6 years in eastern China, and the protective effect of breastfeeding against overweight or overweight/obesity could be confirmed. However, the effects of breastfeeding on thinness, overweight, and obesity may change or become invalid in some subgroups, suggesting that there may be potential interactions between feeding patterns and influential factors.


Assuntos
Obesidade Infantil , Magreza , Criança , Feminino , Humanos , Recém-Nascido , Índice de Massa Corporal , Aleitamento Materno , China/epidemiologia , Eletrólitos , Sobrepeso/epidemiologia , Obesidade Infantil/epidemiologia , Obesidade Infantil/etiologia , Obesidade Infantil/prevenção & controle , Aptidão Física , Prevalência , Estudos Retrospectivos , Magreza/epidemiologia
6.
Zhongguo Zhong Yao Za Zhi ; 35(6): 799-802, 2010 Mar.
Artigo em Zh | MEDLINE | ID: mdl-20545213

RESUMO

For exploration on the academic thought on processing of Chinese herbal medicine the basic theory and methods, textual research of the scientific of Zhang Zhongiing on processing of Chinese herbal medicine was summarized, and the historical significance on academic thought of Zhang Zhongjing on processing of Chinese herbal medicine was analyzed. Regarded Zhang Zhongjing is the ancestor of processing of Chinese herbal medicine to lay the theoretical foundation on processing of Chinese herbal medicine for later.


Assuntos
Medicamentos de Ervas Chinesas/farmacologia , Pesquisas sobre Atenção à Saúde , Saúde Holística , Medicina Tradicional Chinesa/métodos , Aceitação pelo Paciente de Cuidados de Saúde/estatística & dados numéricos , Povo Asiático , Conservação dos Recursos Naturais , Medicina Herbária/métodos , Humanos , Fitoterapia
7.
Chem Commun (Camb) ; 53(97): 13019-13022, 2017 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-29164192

RESUMO

Hierarchically porous N and S co-doped carbon was prepared by using 2,5-dihydroxy-1,4-benzoquinone as the carbon source, thiourea as the N and S source, and SiO2 particles as the template. Using the material as the catalyst, oxidative coupling of silanes with alcohols was conducted for the first time under metal-free conditions.

8.
ChemSusChem ; 9(5): 478-84, 2016 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-26834034

RESUMO

Openly-structured g-C3 N4 microspheres (CNMS) are developed through a well-controlled strategy. These materials have unique features of open 3 D structure, ordered hierarchical porosity, and improved optical and electronic properties. Hydrogen evolution from water is performed under a 300 W Xe lamp with a cut-off filter (λ>420 nm) and Pt nanoparticles are used as the co-catalyst (3.0 wt%). The catalyst prepared at 600 °C (CNMS-600) has a hydrogen evolution rate (HER) of 392 µmol h(-1) (apparent quantum yield, AQY=6.3%) at 420 nm. This value is higher than that of g-C3 N4 nanosheets prepared through thermal oxidation, liquid exfoliation, or chemical exfoliation. The HER value is only 27 µmol h(-1) (AQY=0.43%) at 420 nm for bulk g-C3 N4 from melamine. The evolution of openly-structured CNMS was investigated by TEM, FTIR, and XRD. The improved optical and electronic properties were demonstrated through UV/Vis absorption spectra, valence-band X-ray photoelectron spectroscopy, photoluminescence spectroscopy, electron paramagnetic resonance spectroscopy, and electrochemical impedance spectroscopy.


Assuntos
Grafite/química , Hidrogênio/química , Nitrilas/química , Polímeros/química , Água/química , Catálise , Microscopia de Força Atômica , Microscopia Eletrônica de Varredura , Processos Fotoquímicos , Espectroscopia Fotoeletrônica , Espectrofotometria Ultravioleta
9.
Chem Commun (Camb) ; (17): 2238-40, 2005 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-15856108

RESUMO

Barium sulfate nanotubes perform excellently in supporting sulfates (Pt(SO4)2, HgSO4, Ce(SO4)2 and Pb(SO4)2) for low temperature catalytic conversion of methane to methanol under strongly acidic conditions in a conventional gas-phase reactor.


Assuntos
Sulfato de Bário/química , Chumbo/química , Compostos de Mercúrio/química , Metano/química , Metanol/síntese química , Sulfatos/química , Catálise , Cério/química , Metanol/química , Nanotubos/química , Tamanho da Partícula , Compostos de Platina/química , Temperatura
10.
ChemSusChem ; 7(1): 202-9, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24194497

RESUMO

Levulinic acid is an important platform molecule from biomass-based renewable resources. A sustainable manufacturing process for this chemical and its derivatives is the enabling factor to harness the renewable resource. An integrated catalytic process to directly convert furfural to levulinate ester was developed based on a bifunctional catalyst of Pt nanoparticles supported on a ZrNb binary phosphate solid acid. The hydrogenation of furfural and the following alcoholysis of furfuryl alcohol were performed over this catalyst in a one-pot conversion model. Mesoporous ZrNb binary phosphate was synthesized by a sol-gel method and had a high surface area of 170.1 m(2) g(-1) and a large average pore size of around 8.0 nm. Pt nanoparticles remained in a monodisperse state on the support, and the reaction over Pt/ZrNbPO4 (Pt loading: 2.0 wt%; Zr/Nb, 1:1) gave a very high selectivity to levulinate derivatives (91% in total). The sustainability of this conversion was greatly improved by the process intensification based on the new catalyst, mild reaction conditions, cost abatement in separation and purification, and utilization of green reagents and solvents.


Assuntos
Furaldeído/química , Ácidos Levulínicos/química , Catálise , Ésteres , Nanopartículas Metálicas/química , Nanopartículas Metálicas/ultraestrutura , Microscopia Eletrônica de Transmissão , Nióbio/química , Fosfatos/química , Platina/química , Zircônio/química
12.
J Colloid Interface Sci ; 328(2): 257-62, 2008 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-18922541

RESUMO

The main purpose of this paper is to report the direct removal of trace ionic iodide (I(-)) from acetic acid through porous carbon spheres (PCS) derived from the carbonization of poly(vinylidene chloride). The surface morphology and pore size distribution of the PCS are distinct from activated carbon (AC); thus they possess the peculiar performance of removing ionic iodide from acetic acid. The easy reach of micropores in the PCS was different from that of AC, but similar to that of activated carbon fiber (ACF). The iodide removal process has a strong relation with temperature, which is a typical feature of physical adsorption. The ionic iodide content in acetic acid used in the adsorption experiment was at the parts per billion level, and the factors influencing the adsorption are discussed in detail.

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