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1.
Heliyon ; 10(3): e25280, 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38322895

RESUMO

Background: Extrathyroidal extension (ETE) in papillary thyroid carcinoma (PTC) can be divided into two categories based on different degrees of invasion: microscopic ETE (micro-ETE) and macroscopic ETE (macro-ETE). At present, there is a consensus that macro-ETE significantly affects PTC prognosis, while the prognostic significance of micro-ETE remains controversial. Methods: The clinicopathological and follow-up data for PTC patients who underwent surgical treatment at the Hangzhou First People's Hospital between 2015 and 2018 were retrospectively analyzed. According to the degree of ETE, patients were divided into three groups: non-ETE, micro-ETE and macro-ETE. Cox regression analysis was performed to evaluate the effect of ETE on recurrence-free survival (RFS). The propensity score matching (PSM) method was used to reduce the interference of confounding factors, and Kaplan-Meier curves were utilized to compare the RFS. Results: Both micro- and macro-ETE were associated with some aggressive tumor features, including tumor size, multifocality, and lymph node metastasis. Univariate and multivariate Cox regression analyses showed that macro-ETE was an independent risk factor for recurrence, while micro-ETE was not associated with recurrence. The K-M curves showed that RFS for micro-ETE and non-ETE were not statistically different before and after PSM, while RFS for macro-ETE was significantly shorter than that for non-ETE. Conclusion: The presence of micro-ETE in PTC did not affect prognosis of patients, suggesting that its treatment should be consistent with the treatment for intrathyroidal tumors. The surgical method and the necessity for radioiodine therapy should be carefully evaluated to reduce overtreatment.

2.
Angew Chem Int Ed Engl ; 61(48): e202211626, 2022 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-36181671

RESUMO

Single-crystalline Ni-rich cathode (SC-NCM) has attracted increasing interest owing to its greater capacity retention in advanced solid-state lithium batteries (SSLBs), while suffers from severe interfacial instability during cycling. Here, via atomic layer deposition, Li3 PO4 is introduced to coat SC-NCM (L-NCM), to suppress undesired side reaction and enhance interfacial stability. The dynamic degradation and surface regulation of SC-NCM are investigated inside a working SSLB by in situ atomic force microscopy (AFM). We directly observe the uneven cathode electrolyte interphase (CEI) and surface defects on pristine SC-NCM particle. Remarkably, the formed amorphous LiF-rich CEI on L-NCM maintains its initial structure upon cycling, and thus endows the battery with improved cycling stability and excellent rate capability. Such on-site tracking provides deep insights into surface mechanism and structure-reactivity correlation of SC-NCM, and thus benefits the optimizations of SSLBs.

3.
Front Endocrinol (Lausanne) ; 13: 974755, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36004348

RESUMO

Background: Accurate evaluation of the risk of papillary thyroid microcarcinoma (PTMC) is the key to treatment. However, the maximum diameter (MD), which is currently used in various staging systems, may not truly reflect the aggressiveness of multifocal tumors. Methods: Clinical and pathological data for 1001 patients with papillary thyroid carcinoma who underwent surgery at the Hangzhou First People's Hospital were retrospectively analyzed. First, the relationship between total tumor diameter (TTD) and clinicopathological features in multifocal PTMC was explored. Then, patients were divided into subgroups according to the TTD. The baseline was consistent after using the propensity score matching method, and the differences between groups were compared. In addition, the effectiveness of TTD and MD in evaluating central lymph node metastasis (CLNM) was analyzed and compared. Results: TTD is associated with a range of clinicopathological features, including lymph node metastasis, extrathyroidal extension, and risk stratification. Assuming the same MD and number of foci, the invasiveness of multifocal PTMC with TTD >1 cm was significantly higher than that with TTD <1 cm, and even higher than unifocal non-PTMC. Moreover, the efficiency of TTD in predicting CLNM was also significantly higher than that of MD. Conclusion: For multifocal PTMC, TTD is a more realistic indicator of tumor biological characteristics than MD. The aggressiveness of PTMC with TTD >1 cm was significantly enhanced, and surgical treatment should be actively sought in such cases.


Assuntos
Neoplasias da Glândula Tireoide , Carcinoma Papilar , Humanos , Metástase Linfática , Pontuação de Propensão , Estudos Retrospectivos , Neoplasias da Glândula Tireoide/patologia , Neoplasias da Glândula Tireoide/cirurgia
4.
Chem Commun (Camb) ; 58(57): 7920-7923, 2022 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-35758402

RESUMO

An artificial "salt-in-polymer" SEI, composed of poly-(1,3-dioxolane) and high-modulus fluorinated products generated from the in situ decomposition of Li salts, was constructed on the surface of Li-MSiOx particles. This LiF-rich SEI helps to maintain the structural integrity of Li-MSiOx particles and improves the Li storage reversibility of the Li-MSiOx anode.

5.
Front Endocrinol (Lausanne) ; 12: 741289, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34867784

RESUMO

Purpose: Development and validation of a nomogram for the prediction of lateral lymph node metastasis (LLNM) in medullary thyroid carcinoma (MTC). Methods: We retrospectively reviewed the clinical features of patients with MTC in the Surveillance, Epidemiology, and End Results (SEER) database between 2010 and 2017 and in our Department of Surgical Oncology, Hangzhou First People's Hospital between 2009 and 2019. The log-rank test was used to compare the difference in the Kaplan-Meier (K-M) curves in recurrence and survival. The nomogram was developed to predict the risk of LLNM in MTC patients. The prediction efficiency of the predictive model was assessed by area under the curve (AUC) and concordance index (C-index) and calibration curves. Decision curve analysis (DCA) was performed to determine the clinic value of the predictive model. Result: A total of 714 patients in the SEER database and 35 patients in our department were enrolled in our study. Patients with LLNM had worse recurrence rate and cancer-specific survival (CSS) compared with patients without LLNM. Five clinical characteristics including sex, tumor size, multifocality, extrathyroidal extension, and distant metastasis were identified to be associated with LLNM in MTC patients, which were used to develop a nomogram. Our prediction model had satisfied discrimination with a C-index of 0.825, supported by both training set and internal testing set with a C-index of 0.825, and 0.816, respectively. DCA was further made to evaluate the clinical utility of this nomogram for predicting LLNM. Conclusions: Male sex, tumor size >38mm, multifocality, extrathyroidal extension, and distant metastasis in MTC patients were significant risk factors for predicting LLNM.


Assuntos
Carcinoma Neuroendócrino/patologia , Metástase Linfática/diagnóstico , Neoplasias da Glândula Tireoide/patologia , Adulto , Idoso , Área Sob a Curva , Feminino , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia , Valor Preditivo dos Testes , Prognóstico , Estudos Retrospectivos , Fatores de Risco , Programa de SEER , Caracteres Sexuais , Análise de Sobrevida
6.
Front Endocrinol (Lausanne) ; 12: 759049, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34803921

RESUMO

Purpose: To investigate the prognostic significance of extranodal extension (ENE) in papillary thyroid cancer (PTC). Methods: Seven hundred forty-three PTC patients were enrolled in the study from January 2014 to December 2017. The patients were dichotomized according to the presence of ENE. Logistic analysis was used to compare differences between the two groups. Kaplan-Meier (K-M) curve and propensity score matching (PSM) analyses were used for recurrence-free survival (RFS) comparisons. Cox regression was performed to analyze the effects of ENE on RFS in PTC. Results: Thirty-four patients (4.58%) had ENE. Univariate analysis showed that age, tumor size, extrathyroidal extension, and nodal stage were associated with ENE. Further logistic regression analysis showed that age, extrathyroidal extension, and nodal stage remained statistically significant. Evaluation of K-M curves showed a statistically significant difference between the two groups before and after PSM. Cox regression showed that tumor size and ENE were independent risk factors for RFS. Conclusions: Age ≥55 years, extrathyroidal extension, and lateral cervical lymph node metastasis were identified as independent risk factors for ENE. ENE is an independent prognostic factor in PTC.


Assuntos
Linfonodos/patologia , Câncer Papilífero da Tireoide/patologia , Neoplasias da Glândula Tireoide/patologia , China/epidemiologia , Feminino , Humanos , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Prognóstico , Pontuação de Propensão , Estudos Retrospectivos , Câncer Papilífero da Tireoide/diagnóstico , Câncer Papilífero da Tireoide/mortalidade , Neoplasias da Glândula Tireoide/diagnóstico , Neoplasias da Glândula Tireoide/mortalidade
7.
ACS Appl Mater Interfaces ; 13(21): 24916-24924, 2021 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-34027654

RESUMO

Microsized SiOx has been vigorously investigated as an advanced anode material for next-generation lithium-ion batteries. However, its practical application is seriously hampered by its huge volume variation during the repeated (de)lithiation process, which destroys the microparticle structure and results in rapid capacity fading. Herein, we propose the usage of trans-difluoroethylene carbonate (DFEC) as an electrolyte additive to maintain the structural integrity of microsized SiOx with a uniform carbon layer (SiOx@C). Compared with ethylene carbonate and fluoroethylene carbonate, DFEC has lower lowest unoccupied molecular orbital energy and higher reduction potential, which is easily reduced and promotes the in situ formation of a more stable LiF-rich solid electrolyte interphase (SEI) on the surface of anode materials. The LiF-rich SEI exhibits enhanced mechanical rigidity and ionic conductivity, thus enabling the microsized SiOx@C anodes' excellent lithium storage stability and high average Coulombic efficiency.

8.
ACS Appl Mater Interfaces ; 12(24): 27202-27209, 2020 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-32436378

RESUMO

Carbon-coated SiOx microparticles (SiOx/C) demonstrate attractive potential for anode use in high-energy-density lithium-ion batteries due to high capacity and proper cycling stability. However, the excessive irreversible consumption of Li ions during the initial cycling remains a serious challenge arising from the limited lithium in full cells. Here, we endow SiOx/C anode with high initial Coulombic efficiency using the chemical pre-lithiation strategy. The lithium silicate is uniformly pregenerated in SiOx/C microparticles, which could effectively counteract the irreversible consumption of Li ions and avoid the complicated pre-lithiation process. Moreover, this strategy guarantees the structural integrity and processability of anode materials because of the homogeneous Li-organic complex solution pre-lithiation and high-temperature calcination process. The obtained SiOx/C microparticles can be applied as anode materials by directly mixing with commercial graphite, which demonstrates proper specific capacity, high initial Coulombic efficiency, and excellent cycling performance. Furthermore, the pouch cells using LiNi0.8Co0.1Mn0.1O2 cathodes and the as-prepared anodes exhibit high energy density (301 Wh kg-1) and satisfactory cycling stability (93.3% capacity retention after 100 cycles).

9.
ACS Appl Mater Interfaces ; 10(43): 37023-37030, 2018 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-30299921

RESUMO

A novel covalent organic framework polymer material that bears conjugated anthraquinone and triazine units in its skeleton has been prepared via a facile one-pot condensation reaction and employed as an anode material for Li-ion batteries. The conjugated units consist of C═N groups, C═O groups, and benzene groups, which enable a 17-electron redox reaction with Li per repeating unit and bring a theoretical specific capacity of 1450 mA h g-1. The polymer also shows a large specific surface area and a hierarchically porous structure to trigger interfacial Li storage and contribute to an additional capacity. The highly conductive conjugated polymer skeleton enables fast electron transport to facilitate the Li storage. In this way, the polymer electrode shows a large specific capacity and favorable cycling and rate performance, making it an appealing anode choice for the next-generation high-energy batteries.

10.
ACS Appl Mater Interfaces ; 10(6): 5543-5550, 2018 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-29338167

RESUMO

In this work, nitrogen-doped LaNiO3 perovskite was prepared and studied, for the first time, as a bifunctional electrocatalyst for oxygen cathode in a rechargeable lithium-oxygen battery. N doping was found to significantly increase the Ni3+ contents and oxygen vacancies on the bulk surface of the perovskite, which helped to promote the oxygen reduction reaction and oxygen evolution reaction of the cathode and, therefore, enabled reversible Li2O2 formation and decomposition on the cathode surface. As a result, the oxygen cathodes loaded with N-doped LaNiO3 catalyst showed an improved electrochemical performance in terms of discharge capacity and cycling stability to promise practical Li-O2 batteries.

11.
ACS Appl Mater Interfaces ; 8(34): 22261-9, 2016 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-27502841

RESUMO

A highly conductive sulfur cathode is crucial for improving the kinetic performance of a Li-S battery. The encapsulation of sulfur in porous nanocarbons is expected to benefit the Li(+) migration, yet the e(-) conduction is still to be improved due to a low graphitization degree of a conventional carbon substrate, especially that pyrolyzed from carbohydrates or polymers. Aiming at facilitating the e(-) conduction in the cathode, here we propose to use ketjen black, a highly graphitized nanocarbon building block to form a conductive network for electrons in a biomass-derived, hierarchically porous carbon sponge by a easily scaled-up approach at a low cost. The specifically designed carbon host ensures a high loading and good retention of active sulfur, while also provides a faster electron transmission to benefit the lithiation/delithiation kinetics of sulfur. The sulfur cathode prepared from the carbon network shows excellent cycling and rate performance in a Li-S battery, rendering its practicality for emerging energy storage opportunities such as grids or automobiles.

12.
ACS Appl Mater Interfaces ; 6(11): 8789-95, 2014 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-24764111

RESUMO

To exploit the high energy density of lithium-sulfur batteries, porous carbon materials have been widely used as the host materials of the S cathode. Current studies about carbon hosts are more frequently focused on the design of carbon structures rather than modification of its properties. In this study, we use boron-doped porous carbon materials as the host material of the S cathode to get an insightful investigation of the effect of B dopant on the S/C cathode. Powder electronic conductivity shows that the B-doped carbon materials exhibit higher conductivity than the pure analogous porous carbon. Moreover, by X-ray photoelectron spectroscopy, we prove that doping with B leads to a positively polarized surface of carbon substrates and allows chemisorption of S and its polysulfides. Thus, the B-doped carbons can ensure a more stable S/C cathode with satisfactory conductivity, which is demonstrated by the electrochemical performance evaluation. The S/B-doped carbon cathode was found to deliver much higher initial capacity (1300 mA h g(-1) at 0.25 C), improved cyclic stability, and rate capability when compared with the cathode based on pure porous carbon. Electrochemical impedance spectra also indicate the low resistance of the S/B-doped C cathode and the chemisorption of polysulfide anions because of the presence of B. These features of B doping can play the positive role in the electrochemical performance of S cathodes and help to build better Li-S batteries.

13.
ACS Appl Mater Interfaces ; 4(9): 4858-63, 2012 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-22931115

RESUMO

Graphene-wrapped lithium-excess layered hybrid materials (Li(2)MnO(3)·LiMO(2), M = Mn, Ni, Co, hereafter abbreviated as LMNCO) have been synthesized and investigated as cathode materials for lithium-ion batteries. Cyclic voltammetry measurement shows a significant reduction of the reaction overpotential in benefit of the graphene conducting framework. The electrochemical impedance spectroscopy results reveal that the graphene can greatly reduce the cell resistance, especially the charge transfer resistance. Our investigation demonstrates that the graphene conducting framework can efficiently alleviate the polarization of pristine LMNCO material leading to an outstanding enhancement in cell performance and cycling stability. The superior electrochemical properties support the fine hybrid structure design by enwrapping active materials in graphene nanosheets for high-capacity and high-rate cathode materials.


Assuntos
Fontes de Energia Elétrica , Grafite/química , Lítio/química , Técnicas Eletroquímicas , Eletrodos , Óxidos/química
14.
J Am Chem Soc ; 134(5): 2512-5, 2012 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-22260540

RESUMO

Germanium is a promising high-capacity anode material for lithium ion batteries, but it usually exhibits poor cycling stability because of its huge volume variation during the lithium uptake and release process. A double protection strategy to improve the electrode performance of Ge through the use of Ge@C core-shell nanostructures and reduced graphene oxide (RGO) networks has been developed. The as-synthesized Ge@C/RGO nanocomposite showed excellent cycling performance and rate capability in comparison with Ge@C nanoparticles when used as an anode material for Li ion batteries, which can be attributed to the electronically conductive and elastic RGO networks in addition to the carbon shells and small particle sizes of Ge. The strategy is simple yet very effective, and because of its versatility, it may be extended to other high-capacity electrode materials with large volume variations and low electrical conductivities.


Assuntos
Carbono/química , Germânio/química , Grafite/química , Nanopartículas/química , Eletrodos , Tamanho da Partícula , Propriedades de Superfície
15.
Phys Chem Chem Phys ; 14(8): 2934-9, 2012 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-22274568

RESUMO

An electronically conducting 3D network of reduced graphene oxide (RGO) was introduced into LiNi(1/3)Mn(1/3)Co(1/3)O(2) (LNMC) cathode material in a special nano/micro hierarchical structure. The rate test and cycling measurement showed that the hierarchical networks remarkably improve the high rate performance of LNMC electrode for lithium-ion batteries. The effect of RGO conducting networks on kinetic property was investigated by electrochemical impedance spectroscopy (EIS) and potentiostatic intermittent titration (PITT). The EIS results reveal that the RGO network greatly decreases the resistance of lithium batteries, especially the charge transfer resistance which can be attributed to the significantly improved conducting networks. The enhancement of apparent diffusion coefficient by the RGO conducting networks is shown by PITT. The power performance was found to be limited by the electrical conduction in the two-phase region, which can be greatly facilitated by the hierarchical RGO network together with carbon black. The as-obtained LNMC/RGO cathode exhibits an outstanding electrochemical property supporting the design idea of electronically conducting 3D networks for the high-energy and high-power lithium-ion batteries.

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