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1.
Inorg Chem ; 63(3): 1562-1574, 2024 Jan 22.
Artículo en Inglés | MEDLINE | ID: mdl-38197729

RESUMEN

Compared to the high-temperature hot injection (HI) technique, the room-temperature supersaturated recrystallization (SR) approach is more hopeful to realize the industrialized production of CsPbX3 (X = Cl, Br, and I) nanomaterials. However, accurate compositional control of the product is still difficult, and the role and underlying mechanism of antisolvents in the reprecipitation process remain unclear. Herein, CsPbBr3 particles and CsPbBr3/Cs4PbBr6 composites with certain proportions are synthesized using different antisolvents with the SR method. By adjustment of the polarity or functional group of antisolvents, it is found that the functional groups of antisolvents have a major impact on the composition of the products. Furthermore, the influential mechanism of different antisolvents on the compositions of products is investigated by combining electrostatic potential calculations and ultraviolet-visible absorption spectroscopy. It suggests that the interaction between functional groups of antisolvents and organic ligands influences the coordination status of the intermediate Pb-complex and further affects the separating rate of the Pb(II)-intermediate, leading to the formation of products with different compositions. A physicochemical mechanism is proposed to explain the formation of Cs4PbBr6 and CsPbBr3. This work deepens the understanding of the formation mechanism of all-inorganic metal halide perovskite-related materials based on the SR method and provides new routes to achieve their controllable preparation.

2.
Surg Innov ; 24(1): 29-34, 2017 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-27634477

RESUMEN

The study assessed the role of an activated carbon nanoparticle lymphatic tracer in reducing unintentional damage to the parathyroid glands during thyroidectomy for papillary thyroid non-microcarcinoma diagnosed intraoperatively by cryosections. A total of 103 patients with papillary thyroid non-microcarcinomas diagnosed by intraoperative cryosection were randomly assigned to receive routine radical thyroidectomy or radical thyroidectomy following administration of activated carbon nanoparticle lymphatic tracer to the contralateral thyroid, at the department of Thyroid Surgery, Sun Yat-sen Memorial Hospital (Guangzhou, China), between January 2012 and May 2013. The success of level VI lymphadenectomy and postoperative parathyroid function were compared. Administration of the activated carbon nanoparticle lymphatic tracer did not affect the frequency of recovered lymph nodes containing metastases; however, it did significantly reduce the incidence of permanent and transient hypoparathyroidism from 2 to 0 and 18 to 6, and reduced the mean recovery time for transient hypoparathyroidism from 57.0 days to 22.3 days. Administration of activated carbon nanoparticles to the contralateral thyroid after intraoperative cryosections did not contribute to lymphadenectomy for papillary thyroid non-microcarcinoma, but significantly protected parathyroid functions. This approach could decrease the morbidity of radical thyroidectomy and the occurrence of hypoparathyroidism.


Asunto(s)
Carbono , Carcinoma Papilar/cirugía , Hipoparatiroidismo/prevención & control , Nanopartículas , Neoplasias de la Tiroides/cirugía , Tiroidectomía/métodos , Adulto , Carcinoma Papilar/patología , Femenino , Humanos , Hipoparatiroidismo/etiología , Escisión del Ganglio Linfático , Ganglios Linfáticos/patología , Masculino , Persona de Mediana Edad , Glándulas Paratiroides , Neoplasias de la Tiroides/patología , Tiroidectomía/efectos adversos
3.
Nanotechnology ; 27(29): 295703, 2016 Jul 22.
Artículo en Inglés | MEDLINE | ID: mdl-27285480

RESUMEN

Bicrystalline α-Fe2O3 nanoblades (NBs) synthesized by thermal oxidation of iron foils were reduced in vacuum, to study the effect of reduction treatment on microstructural changes and photocatalytic properties. After the vacuum reduction, most bicrystalline α-Fe2O3 NBs transform into single-layered NBs, which contain more defects such as oxygen vacancies, perfect dislocations and dense pores. By comparing the photodegradation capability of non-reduced and reduced α-Fe2O3 NBs over model dye rhodamine B (RhB) in the presence of hydrogen peroxide, we find that vacuum-reduction induced microstructural defects can significantly enhance the photocatalytic efficiency. Even after 10 cycles, the reduced α-Fe2O3 NBs still show a very high photocatalytic activity. Our results demonstrate that defect engineering is a powerful tool to enhance the photocatalytic performance of nanomaterials.

4.
Phys Chem Chem Phys ; 18(40): 27967-27975, 2016 Oct 12.
Artículo en Inglés | MEDLINE | ID: mdl-27711427

RESUMEN

The photocatalytic mechanism of a Cu2O/CuO hybrid system is disclosed in detail by density functional theory (DFT) calculations. The synergistic relationship of the two counterparts is confirmed by hydrogen peroxide (H2O2) formation on the CuO nanowires and dissociation on the Cu2O nanoparticles; this enables the system to self-sufficiently produce hydroxyl radicals, which is highly efficient in the photocatalytic degradation of methyl orange. The exposed surfaces are found to be crucial in the cooperative photocatalytic system, especially the Cu2O(111) surface, in the dissociation of H2O2. The distinct positions of the conduction band minimum and valence band maximum for CuO and Cu2O and synergic surface reactions enable the effective utilization of the electrons and holes generated by visible-light irradiation. Our results will contribute to a greater understanding of the specific mechanism of photodegradation catalyzed by Cu2O/CuO heterostructures, which may lead to promising directions in structure optimization for photocatalysts with high photocatalytic efficiency.

5.
Phys Chem Chem Phys ; 16(33): 17487-92, 2014 Sep 07.
Artículo en Inglés | MEDLINE | ID: mdl-25019491

RESUMEN

Novel hybrid nanocomposites of Cu2O nanoparticles (NPs) partially embedded in CuO nanowires (NWs) were produced by simple thermal reduction of CuO NWs in a vacuum. It is found that most Cu2O NPs adopt two regular shapes, one being cubic and the other being octahedral. The shape selection of the Cu2O nanocrystals is governed by the orientation relationship between Cu2O NPs and CuO NWs. The formation of such hierarchical hybrid nanostructures is induced by the topotactic reduction of CuO NWs. Compared with pure CuO NWs, the polyhedral Cu2O NP-CuO NW hierarchical hybrid nanostructures exhibit enhanced ability to photodegrade methyl orange under visible light, which is attributed to the synergic effects of CuO NWs and Cu2O NPs.

6.
Behav Sci (Basel) ; 14(6)2024 Jun 18.
Artículo en Inglés | MEDLINE | ID: mdl-38920837

RESUMEN

Reward has been shown to influence selective attention, yet previous research has primarily focused on rewards associated with specific locations or features, with limited investigation into the impact of a reward object on object-based attention (OBA). Therefore, it remains unclear whether objects previously associated with rewards affect OBA. To address this issue, we conducted two experiments using a paradigm that combined a reward training phase with a modified two-rectangle paradigm. The results indicate that a reward object modulates both space-based attention (SBA) and OBA. When cues appear on a reward object, the effects of both SBA and OBA are amplified compared to when cues appear on a no-reward object. This finding supports the value-driven attentional capture (VDAC) theory, which suggests that a reward object gain enhanced saliency to capture attention, thereby providing a theoretical support for the treatment of conditions such as drug addiction.

7.
Cancer Commun (Lond) ; 43(11): 1229-1243, 2023 11.
Artículo en Inglés | MEDLINE | ID: mdl-37743572

RESUMEN

OBJECTIVE: Adopting a healthy lifestyle, including regular physical activity, is widely believed to decrease cancer risk. This study aimed to quantitatively establish the dose-response relationships between total physical activity and the risk of breast, colon, lung, gastric, and liver cancers. METHODS: A systematic review and dose-response analysis were conducted using PubMed and Embase from January 1, 1980 to March 20, 2023. Prospective cohort studies that examined the association between physical activity and the risks of any of the 5 outcomes were included. The search was confined to publications in the English language with a specific focus on human studies. Physical activity is standardized by using the data from US National Health and Nutrition Examination Surveys (NHANES) and the Global Burden of Disease 2019 database. RESULTS: A total of 98 studies, involving a combined population of 16,418,361 individuals, were included in the analysis. Among the included studies, 57 focused on breast cancer, 17 on lung cancer, 23 on colon cancer, 5 on gastric cancer, and 7 on liver cancer. Overall, elevated levels of physical activity exhibited an inverse correlation with the risk of cancer. The dose-response curve for lung cancer exhibited a non-linear pattern, with the greatest benefit risk reduction observed at 13,200 MET-minutes/week of physical activity, resulting in a 14.7% reduction in risk (relative risk 0.853, uncertainty interval 0.798 to 0.912) compared to the inactive population. In contrast, the dose-response curves for colon, gastric, breast, and liver cancers showed linear associations, indicating that heightened levels of total physical activity were consistently associated with reduced cancer risks. However, the increase in physical activity yielded a smaller risk reduction for colon and gastric cancers compared to breast and liver cancers. Compared to individuals with insufficient activity (total activity level < 600 MET-minutes/week), individuals with high levels of activity (≥ 8,000 MET-minutes/week) experienced a 10.3% (0.897, 0.860 to 0.934) risk reduction for breast cancer; 5.9% (0.941, 0.884 to 1.001) for lung cancer; 7.1% (0.929, 0.909 to 0.949) for colon cancer; 5.1% (0.949, 0.908 to 0.992) for gastric cancer; 17.1% (0.829, 0.760 to 0.903) for liver cancer. CONCLUSIONS: This study demonstrated a significant inverse relationship between total physical activity and the risk of breast, gastric, liver, colon, and lung cancers.


Asunto(s)
Neoplasias de la Mama , Neoplasias del Colon , Neoplasias Hepáticas , Neoplasias Pulmonares , Neoplasias Gástricas , Humanos , Femenino , Estudios Prospectivos , Carga Global de Enfermedades , Encuestas Nutricionales , Ejercicio Físico , Neoplasias de la Mama/epidemiología , Neoplasias del Colon/epidemiología , Medición de Riesgo , Neoplasias Hepáticas/epidemiología , Neoplasias Hepáticas/prevención & control
8.
ACS Appl Mater Interfaces ; 13(37): 44777-44785, 2021 Sep 22.
Artículo en Inglés | MEDLINE | ID: mdl-34496569

RESUMEN

All-inorganic metal halide perovskites have attracted considerable attention due to their high application potentials in optoelectronics, photonics, and energy conversion. Herein, two-dimensional (2D) CsPbBr3 nanosheets with a thickness of about 3 nm have been synthesized through a simple chemical process based on a hot-injection technique. The lateral dimension of CsPbBr3 nanosheets ranges from 11 to 110 nm, which can be tuned by adjusting the ratio of short ligands (octanoic acid and octylamine) over long ligands (oleic acid and oleylamine). The nanosheets result from the self-assembly of CsPbBr3 nanocubes with an edge length of about 3 nm, which possess the same crystal orientation. In addition, an amorphous region of about 1 nm in width is found between adjacent nanocubes. To investigate both the structure and the growth mechanism of these nanosheets, microstructural characterizations at the atomic scale are conducted, combined with X-ray diffraction analysis, 1H nuclear magnetic resonance (1H NMR) measurement, and density functional theory (DFT) calculation, aiming to determine the configuration of different ligands adsorbed onto CsPbBr3. Our results suggest that the adjacent nanocubes are mainly connected together by short ligands and inclined long ligands. On the basis of the DFT calculation results, a relationship is derived for the volume ratio of short ligands over long ligands and the lateral dimensions of CsPbBr3 nanosheets. Moreover, a physicochemical mechanism is proposed to explain the 2D growth of CsPbBr3 nanosheets. Such a finding provides new insights regarding the well-ordered self-arrangement of CsPbBr3 nanomaterials, as well as new routes to synthesize 2D CsPbX3 (X = Cl and I) nanosheets of suitable dimensions for specific and large-scale applications.

9.
Asia Pac J Clin Oncol ; 15(5): e167-e174, 2019 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-31111675

RESUMEN

BACKGROUND: Long-term (> 5 years) bladder cancer survivors represent a distinct subgroup of bladder cancer patients and information about the causes of death in this subgroup is limited. The aim of this study was to review the causes of death in long-term bladder cancer survivors. METHOD: The Surveillance, epidemiology and end results (SEER) database was used to analyze the causes of death of long-term bladder cancer survivors. Patients' characteristics and survival outcomes were reported for the entire cohort in our study. Kaplan-Meier analysis and Cox proportional hazard model for survival analysis. RESULTS: A total of 147 781 bladder cancer patients with >5 years survival were identified. This cohort included 81 843 patients surviving 5-10 years and 65 938 patients surviving >10 years. Among the patients who survived 5-10 years, 6.9% died because of primary bladder cancer, 11.0% due to cardiac disease and 7.7% due to nonmalignant pulmonary disease. Among patients surviving >10 years, 3.1% died because of primary bladder cancer, 8.6% due to cardiac disease and 5.8% due to nonmalignant pulmonary disease. On multivariate analysis, factors associated with longer cardiac disease-specific survival among long-term bladder cancer survivors include younger age at diagnosis(<40 years; vs. 40-69 years, P = 0.030 or >69 years, P < 0.001), married status (vs. single status, P < 0.001), white race (vs. African American race, P = 0.002), male (vs. female, P < 0.001), grade I (vs. grade III, P = 0.003 or grade IV, P < 0.001). CONCLUSION: The probability of death from primary bladder cancer is still important among various causes of death even 20 years after being diagnosed with bladder cancer. Furthermore, cardiopulmonary causes contributed to a considerable proportion of deaths in long-term bladder cancer survivors.


Asunto(s)
Supervivientes de Cáncer/estadística & datos numéricos , Causas de Muerte , Cardiopatías/mortalidad , Enfermedades Pulmonares/mortalidad , Neoplasias de la Vejiga Urinaria/mortalidad , Adulto , Anciano , China/epidemiología , Estudios de Cohortes , Femenino , Cardiopatías/etiología , Cardiopatías/patología , Humanos , Enfermedades Pulmonares/etiología , Enfermedades Pulmonares/patología , Masculino , Persona de Mediana Edad , Pronóstico , Programa de VERF , Tasa de Supervivencia , Neoplasias de la Vejiga Urinaria/complicaciones , Neoplasias de la Vejiga Urinaria/epidemiología
10.
Chin J Cancer ; 37(1): 3, 2018 01 26.
Artículo en Inglés | MEDLINE | ID: mdl-29370848

RESUMEN

BACKGROUND: Accurate evaluation of lymph node metastasis in bladder cancer (BCa) is important for disease staging, treatment selection, and prognosis prediction. In this study, we aimed to evaluate the diagnostic accuracy of computed tomography (CT) and magnetic resonance imaging (MRI) for metastatic lymph nodes in BCa and establish criteria of imaging diagnosis. METHODS: We retrospectively assessed the imaging characteristics of 191 BCa patients who underwent radical cystectomy. The data regarding size, shape, density, and diffusion of the lymph nodes on CT and/or MRI were obtained and analyzed using Kruskal-Wallis test and χ2 test. The optimal cutoff value for the size of metastatic node was determined using the receiver operating characteristic (ROC) curve analysis. RESULTS: A total of 184 out of 3317 resected lymph nodes were diagnosed as metastatic lymph nodes. Among 82 imaging-detectable lymph nodes, 51 were confirmed to be positive for metastasis. The detection rate of metastatic nodes increased along with more advanced tumor stage (P < 0.001). Once the ratio of short- to long-axis diameter ≤ 0.4 or fatty hilum was observed in lymph nodes on imaging, it indicated non-metastases. Besides, lymph nodes with spiculate or obscure margin or necrosis indicated metastases. Furthermore, the short diameter of 6.8 mm was the optimal threshold to diagnose metastatic lymph node, with the area under ROC curve of 0.815. CONCLUSIONS: The probability of metastatic nodes significantly increased with more advanced T stages. Once lymph nodes are detected on imaging, the characteristic signs should be paid attention to. The short diameter > 6.8 mm may indicate metastatic lymph nodes in BCa.


Asunto(s)
Imagen por Resonancia Magnética , Neoplasias Pélvicas/diagnóstico por imagen , Tomografía Computarizada por Rayos X , Neoplasias de la Vejiga Urinaria/diagnóstico por imagen , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Escisión del Ganglio Linfático , Ganglios Linfáticos/patología , Metástasis Linfática/diagnóstico por imagen , Metástasis Linfática/patología , Masculino , Persona de Mediana Edad , Estadificación de Neoplasias , Neoplasias Pélvicas/patología , Neoplasias Pélvicas/secundario , Neoplasias Pélvicas/cirugía , Pelvis/diagnóstico por imagen , Pelvis/patología , Neoplasias de la Vejiga Urinaria/patología , Neoplasias de la Vejiga Urinaria/cirugía
11.
Asia Pac J Clin Oncol ; 14(5): e332-e335, 2018 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-29767477

RESUMEN

AIM: To explore the application of intraoperative neurological monitoring in residual thyroidectomy 5-15 days after thyroid cancer operation and the influence on postoperative serum thyroglobulin (Tg), recurrent laryngeal nerve and function of parathyroid glands. METHODS: Material of patients receiving thyroid surgery from January 2010 to December 2016 was retrospectively analyzed. Cases meeting with standards were enrolled for analysis and the patients were divided into neurological monitoring group and non-neurological monitoring group in line with the use of neurological monitoring during the operation. Recurrent laryngeal nerve-injured hoarseness, hypoparathyroidism and concentration of serum Tg before and after the surgery were collected and analyzed. RESULTS: Four-hundred and thirty-five patients met with standards, among which 227 from neurological monitoring group and 208 from non-neurological monitoring group. Temporary hoarseness rate of non-neurological monitoring group and neurological monitoring group was 8.67% and 2.2%. Permanent hoarseness rate of non-neurological monitoring group and neurological monitoring group was 1.92% and 0.44%. Temporary hypoparathyroidism rate of non-neurological monitoring group and neurological monitoring group was 18.75% and 7.48%. Permanent hypoparathyroidism rate of non-neurological monitoring group and neurological monitoring group was 1.92% and 0.88%. Average Tg concentration 1 month after the surgery in non-neurological monitoring group and neurological monitoring group was 2.82 and 1.37 ng/mL, respectively. Rate of average Tg concentration less than 1 ng/mL 1 month after the surgery in non-neurological monitoring group and neurological monitoring group was 45.06% and 67.4%. CONCLUSION: Intraoperative neurological monitoring can be adopted in residual thyroidectomy in postoperative 5-15 days after primary thyroid cancer surgery, as to reduce incidence rate of recurrent laryngeal nerve injury and hypoparathyroidism and to enhance thorough removal of thyroid tissues and cancer tissues.


Asunto(s)
Monitoreo Intraoperatorio , Complicaciones Posoperatorias , Neoplasias de la Tiroides/cirugía , Tiroidectomía/efectos adversos , Parálisis de los Pliegues Vocales/diagnóstico , Femenino , Humanos , Masculino , Persona de Mediana Edad , Periodo Posoperatorio , Pronóstico , Estudios Retrospectivos , Parálisis de los Pliegues Vocales/etiología
14.
Chin J Cancer ; 36(1): 75, 2017 Sep 12.
Artículo en Inglés | MEDLINE | ID: mdl-28899420

RESUMEN

BACKGROUND: Inflammation-based indexes have been used to predict survival and recurrence in cancer patients. Systemic immune-inflammation index (SII) was reported to be associated with prognosis in some malignant tumors. In the present study, we aimed to explore the association between SII and the prognosis of patients with gastric cancer. METHODS: We retrospectively analyzed data from 444 gastric cancer patients who underwent gastrectomy at the First Affiliated Hospital of Sun Yat-sen University between January 1994 and December 2005. Preoperative SII was calculated. The Chi square test or Fisher's exact test was used to determine the relationship between preoperative SII and clinicopathologic characteristics. Overall survival (OS) rates were estimated using the Kaplan-Meier method, and the effect of SII on OS was analyzed using the Cox proportional hazards model. Receiver operating characteristic (ROC) curves were used to compare the predictive ability of SII, NLR, and PLR. RESULTS: SII equal to or higher than 660 was significantly associated with old age, large tumor size, unfavorable Borrmann classification, advanced tumor invasion, lymph node metastasis, distant metastasis, advanced TNM stage, and high carcino-embryonic antigen level, high neutrophil-lymphocyte ratio, and high platelet-lymphocyte ratio (all P < 0.05). High SII was significantly associated with unfavorable prognosis (P < 0.001) and SII was an independent predictor for OS (P = 0.015). Subgroups analysis further showed significant associations between high SII and short OS in stage I, II, III subgroups (all P < 0.05). SII was superior to NLR and PLR for predicting OS in patients with gastric cancer. CONCLUSION: Preoperative SII level is an independent prognostic factor for OS in patients with gastric cancer.


Asunto(s)
Inflamación/inmunología , Neoplasias Gástricas/inmunología , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Persona de Mediana Edad , Pronóstico , Neoplasias Gástricas/patología , Adulto Joven
15.
Asia Pac J Oncol Nurs ; 8(6): 591-593, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34790841
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