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1.
ACS Appl Mater Interfaces ; 11(5): 5240-5246, 2019 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-30633490

RESUMO

Three PbTiO3 nanostructures were synthesized using a one-step hydrothermal reaction with different TiO2 powders as Ti sources, and their gas-sensing properties were investigated. The sensor comprising PbTiO3 nanoplates (NPs) exhibited a high response (resistance ratio = 80.4) to 5 ppm ethanol at 300 °C and could detect trace concentrations of ethanol down to 100 ppb. Moreover, the sensor showed high ethanol selectivity and nearly the same sensing characteristics despite the wide range of humidity variation from 20 to 80% RH. The mechanism for humidity-independent gas sensing was elucidated using diffuse reflectance infrared Fourier transform spectra. PbTiO3 NPs are new and promising sensing materials that can be used for detecting ethanol in a highly sensitive and selective manner with negligible interference from ambient humidity.

2.
Cancer Commun (Lond) ; 38(1): 23, 2018 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-29764518

RESUMO

BACKGROUND: Few studies have shown nomograms that may predict disease-specific survival (DSS) probability after curative D2 gastrectomy for advanced gastric cancer (AGC), particularly among Chinese patients. This study sought to develop an elaborative nomogram that predicts long-term DSS for AGC in Chinese patients. METHODS: A retrospective study was conducted on 6753 AGC patients undergoing D2 gastrectomy between January 1, 2000 and December 31, 2012 from three large medical hospitals in China. We assigned patients from Sun Yat-sen University Cancer Center to the training set, and patients from the First Affiliated Hospital of China Medical University and Tianjin Medical University Cancer Hospital to two separate external validation sets. A multivariate survival analysis was performed using Cox proportional hazards regression model in a training set, and a nomogram was constructed. Harrell's C-index was used to evaluate discrimination and calibration plots were used to validate similarities between survival probabilities predicted by the nomogram model and actual survival rates in two validation sets. RESULTS: The multivariate Cox regression model identified age, tumor size, location, Lauren classification, lymphatic/venous invasion, depth of invasion, and metastatic lymph node ratio as covariates associated with survival. In the training set, the nomogram exhibited superior discrimination power compared with the 8th American Joint Committee on Cancer TNM classification (Harrell's C-index, 0.82 vs. 0.74; P < 0.001). In two validation sets, the nomogram's discrimination power was also excellent relative to TNM classification (C-index, 0.83 vs. 0.75 and 0.81 vs. 0.74, respectively; P < 0.001 for both). After calibration, the nomogram produced survival predictions that corresponded closely with actual survival rate. CONCLUSIONS: The established nomogram was able to predict 3-, 5-, and 10-year DSS probabilities for AGC patients. Validation revealed that this nomogram exhibited excellent discrimination and calibration capacity, suggesting its clinical utility.


Assuntos
Gastrectomia/métodos , Nomogramas , Avaliação de Resultados em Cuidados de Saúde/métodos , Neoplasias Gástricas/cirurgia , Idoso , Feminino , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Avaliação de Resultados em Cuidados de Saúde/estatística & dados numéricos , Modelos de Riscos Proporcionais , Estudos Retrospectivos , Neoplasias Gástricas/mortalidade , Taxa de Sobrevida
3.
Adv Mater ; 30(6)2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29265518

RESUMO

Despite tellurium being less abundant in the Earth's crust than gold, platinum, or rare-earth elements, the number of industrial applications of tellurium has rapidly increased in recent years. However, to date, many properties of tellurium and its associated compounds remain unknown. For example, formation mechanisms of many tellurium nanostructures synthesized so far have not yet been verified, and it is unclear why tellurium can readily transform to other compounds like silver telluride by simply mixing with solutions containing silver ions. This uncertainty appears to be due to previous misunderstandings about the tellurium structure. Here, a new approach to the tellurium structure via synthesized structures is proposed. It is found that the proposed approach applies not only to these structures but to all other tellurium nanostructures. Moreover, some unique tellurium nanostructures whose formation mechanism are, until now, unconfirmed can be explained.

4.
Cell Physiol Biochem ; 36(4): 1305-15, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26160442

RESUMO

BACKGROUND/AIMS: After myocardial infarction (MI), cardiac fibrosis greatly contributes to left ventricular remodeling and heart failure. The intermediate-conductance calcium-activated potassium Channel (KCa3.1) has been recently proposed as an attractive target of fibrosis. The present study aimed to detect the effects of KCa3.1 blockade on ventricular remodeling following MI and its potential mechanisms. METHODS: Myocardial expression of KCa3.1 was initially measured in a mouse MI model by Western blot and real time-polymerase chain reaction. Then after treatment with TRAM-34, a highly selective KCa3.1 blocker, heart function and fibrosis were evaluated by echocardiography, histology and immunohistochemistry. Furthermore, the role of KCa3.1 in neonatal mouse cardiac fibroblasts (CFs) stimulated by angiotensin II (Ang II) was tested. RESULTS: Myocardium expressed high level of KCa3.1 after MI. Pharmacological blockade of KCa3.1 channel improved heart function and reduced ventricular dilation and fibrosis. Besides, a lower prevalence of myofibroblasts was found in TRAM-34 treatment group. In vitro studies KCa3.1 was up regulated in CFs induced by Ang II and suppressed by its blocker.KCa3.1 pharmacological blockade attenuated CFs proliferation, differentiation and profibrogenic genes expression and may regulating through AKT and ERK1/2 pathways. CONCLUSION: Blockade of KCa3.1 is able to attenuate ventricular remodeling after MI through inhibiting the pro-fibrotic effects of CFs.


Assuntos
Ventrículos do Coração/efeitos dos fármacos , Coração/efeitos dos fármacos , Canais de Potássio Ativados por Cálcio de Condutância Intermediária/antagonistas & inibidores , Infarto do Miocárdio/tratamento farmacológico , Miocárdio/patologia , Pirazóis/uso terapêutico , Remodelação Ventricular/efeitos dos fármacos , Animais , Células Cultivadas , Colágeno/análise , Fibroblastos/efeitos dos fármacos , Fibroblastos/patologia , Fibrose , Ventrículos do Coração/patologia , Canais de Potássio Ativados por Cálcio de Condutância Intermediária/análise , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Infarto do Miocárdio/patologia , Miocárdio/metabolismo
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