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Polycarboxylate (PCE) is a high performance superplasticizer for modern concrete. With the high quality sand becoming precious, more and more low quality sands are used in concrete. However, low quality sands generally contain a relatively high content of montmorillonite (MMT), which could seriously reduce the efficiency of PCE. In order to develop PCE suitable for concrete with low quality sands, the absorption behavior on MMT of PCE with different side chains and acid/ether ratio was investigated. In order to explore the effect of MMT on PCE, two macromonomers were selected, isoprene glycol ether 400(TPEG400) and isoprene glycol ether 2400 (TPEG2400), to synthesize six long and short side chain comb-type PCEs with acid-ether ratios of 1.5:1, 2.5:1 and 3.5:1, respectively. The MMT tolerance mechanism of comb-type PCE in MMT-containing cement slurry was examined by FT-IR, DLS, TOC and other analysis. The PCE with long side chain is much easier to be inserted into the layered structure of MMT, resulting in intercalation absorption. The absorption amount of two kinds of side chain PCE on the MMT particles decreased as the acid ether ratio increases. PCE with long side chains showed shear-thickening properties in MMT-containing cement slurry, on the contrary, short side chains showed shear-thinning properties.
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Two pseudohalide thiocyanate ions (SCN(-) ) have been used to replace two iodides in CH3 NH3 PbI3 , and the resulting perovskite material was used as the active material in solar cells. In accelerated stability tests, the CH3 NH3 Pb(SCN)2 I perovskite films were shown to be superior to the conventional CH3 NH3 PbI3 films as no significant degradation was observed after the film had been exposed to air with a relative humidity of 95 % for over four hours, whereas CH3 NH3 PbI3 films degraded in less than 1.5â hours. Solar cells based on CH3 NH3 Pb(SCN)2 I thin films exhibited an efficiency of 8.3 %, which is comparable to that of CH3 NH3 PbI3 based cells fabricated in the same way.
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OBJECTIVE: To identify risk factors associated with overall survival (OS) for patients undergoing primary hepatic resection for metastatic colorectal cancer. METHODS: The clinical and pathological data were prospectively collected from 191 consecutive patients undergoing primary hepatic resection for colorectal liver metastases from January 2000 to August 2012. The survival curve was drawn by Kaplan-Meier method, and the survival rates were analyzed by Log-rank test. Parametric survival analysis was used to identify predictors of cancer-specific survival. RESULTS: The 5-year overall survival were 38.4% and median survival time was 33 months; 5-year disease-free survival were 23.6%, and the median disease-free survival time was 10.0 months. 5-years survival rate was significantly lower in patients with synchronal metastasis than in patients with heterochronia metastasis (27.4% vs. 51.8%, χ(2) = 6.527, P < 0.05). In overall survival, univariate analysis found 7 risk factors: gender (χ(2) = 5.219), N stage of the primary tumor (χ(2) = 5.591), bilobar metastases (χ(2) = 4.269), number of metastases ≥ 2 (χ(2) = 5.051), disease-free interval ≥ 6 months (χ(2) = 6.527), carcinoembyonic antigen level ≥ 30 µg/L (χ(2) = 4.454), and extrahepatic disease (χ(2) = 5.158). On multivariate analysis, 3 risk factors were found to be independent predictors of poor survival: N stage of the primary tumor (RR = 2.198, 95%CI: 1.146-4.216), disease-free interval ≥ 6 months (RR = 1.840, 95%CI: 1.139-2.973), carcinoembyonic antigen level ≥ 30 µg/L(RR = 1.854, 95%CI: 1.056-3.255). CONCLUSIONS: Resection of liver metastases provides good long-term cancer-specific survival benefit. N stage of the primary tumor, disease-free interval, carcinoembyonic antigen level are important prognostic factors for colorectal liver metastasis.
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Neoplasias Colorrectales/patología , Neoplasias Hepáticas/cirugía , Hígado/cirugía , Adulto , Anciano , Anciano de 80 o más Años , Antígeno Carcinoembrionario/sangre , Supervivencia sin Enfermedad , Femenino , Estudios de Seguimiento , Humanos , Estimación de Kaplan-Meier , Neoplasias Hepáticas/secundario , Masculino , Persona de Mediana Edad , Pronóstico , Factores de Riesgo , Tasa de Supervivencia , Adulto JovenRESUMEN
Halide perovskite materials have attracted worldwide attention in the photovoltaic area due to the rapid improvement in efficiency, from less than 4% in 2009 to 26.1% in 2023 with only a nanometer lever photo-active layer. Meanwhile, this nova star found applications in many other areas, such as light emitting, sensor, etc. This review started with the fundamentals of physics and chemistry behind the excellent performance of halide perovskite materials for photovoltaic/light emitting and the methods for preparing them. Then, it described the basic principles for solar cells and light emitting devices. It summarized the strategies including nanotechnology to improve the performance and the application of halide perovskite materials in these two areas: from structure-property relation to how each component in the devices affects the overall performance. Moreover, this review listed the challenges for the future applications of halide perovskite materials.
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Hepatopancreatic necrosis disease (HPND) is a newly emerging disease in the Chinese mitten crab, Eriocheir sinensis, which has resulted in large economic losses. However, the underlying cause of this disease remains unclear. To better understand the pathogenesis and pathogenic mechanism of HPND, we compared the transcriptome differences of the hepatopancreas of E. sinensis with and without HPND. The analysis yielded > 30 million reads for each sample of three test (with HPND) and three control groups (without HPND). We observed 978 downregulated genes and 644 upregulated genes. Among the gene ontology categories "biological process," "cellular component," and "molecular function", the subcategories cellular process, single-organism process, biological regulation, metabolic process, cell part, organelle, organelle part, binding, and catalytic were enriched. Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis showed that "metabolism of xenobiotics by cytochrome P450," "drug metabolism-cytochrome P450," "chemical carcinogenesis," and "material metabolism" were the "five" most significantly enriched pathways in the hepatopancreas of E. sinensis with HPND. The results revealed that material metabolic abnormalities and drug effects from the external environment might be associated with HPND in the Chinese mitten crab. Considering the wide use of pyrethroids for pond cleaning in Xinghua city, we speculated that pyrethroids might cause HPND in the Chinese mitten crab. Our study provided useful information about the cause and pathogenetic mechanisms of HPND and could help to prevent this disease in production practice.
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Braquiuros/genética , Hepatopáncreas/metabolismo , Transcriptoma , Animales , Braquiuros/metabolismo , Sistema Enzimático del Citocromo P-450/genética , Sistema Enzimático del Citocromo P-450/metabolismo , Hepatopáncreas/efectos de los fármacos , Hepatopáncreas/patología , Necrosis , Xenobióticos/metabolismo , Xenobióticos/toxicidadRESUMEN
Binary transition metal oxides (BTMOs) have been explored as promising candidates in rechargeable lithium-ion battery (LIB) anodes due to their high specific capacity and environmental benignity. Herein, 2D ultrathin NiCo2O4 nanosheets vertically grown on a biomass-derived carbon fiber substrate (NCO NSs/BCFs) were obtained by a facile synthetic strategy. The BCF substrate has superior flexibility and mechanical strength and thus not only offers a good support to NCO NSs/BCFs composites, but also provides high-speed paths for electron transport. Furthermore, 2D NiCo2O4 nanosheets grown vertically present a large contact area between the electrode and the electrolyte, which shortens the ions/electrons transport distance. The nanosheets structure can effectively limit the volume change derived from Li+ insertion and extraction, thus improving the stability of the electrode material. Therefore, the synthesized self-supporting NCO NSs/BCFs electrode displays excellent electrochemical performance, such as a large reversible capacity of 1128 mA·h·g-1 after 80 cycles at a current density of 100 mA·g-1 and a good rate capability of 818.5 mA·h·g-1 at 1000 mA·g-1. Undoubtedly, the cheap biomass carbon source and facile synthesis strategy here described can be extended to other composite materials for high-performance energy-storage and conversion devices.
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It was reported that the main obstacle of Li2ZrO3 as high-temperature CO2 absorbents is the very slow CO2 sorption kinetics, which are ascribed to the gradual formation of compact zirconia and carbonate shells along with inner unreacted lithium zirconate cores; accordingly, the "sticky" Li+ and O2- ions have to travel a long distance through the solid shells by diffusion. We report here that three-dimensional interconnected nanoporous Li2ZrO3 exhibiting ultrafast kinetics is promising for CO2 sorption. Specifically, nanoporous Li2ZrO3 (LZ-NP) exhibited a rapid sorption rate of 10.28 wt %/min with an uptake of 27 wt % of CO2. Typically, the k1 values of LZ-NP (kinetic parameters extracted from sorption kinetics) were nearly 1 order of magnitude higher than the previously reported conventional Li2ZrO3 reaction systems. Its sorption capacity of 25 wt % within â¼4 min is 2 orders of magnitude faster than those obtained using spherical Li2ZrO3 powders. Furthermore, nanoporous Li2ZrO3 exhibited good stability over 60 absorption-desorption cycles, showing its potential for practical CO2 capture applications. CO2 adsorption isotherms for Li2ZrO3 absorbents were successfully modeled using a double-exponential equation at various CO2 partial pressures.
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The technique of pancreatic duct stenting during pancreatic anastomosis can markedly reduce the incidence of postoperative pancreatic fistula (PF) after pancreaticoduodenectomy (PD). The method of drainage includes using either an external or an internal stent; the meta-analysis result shows us that there were no differences in the rates of postoperative complications between PD using internal stents and PD using external stents; internal stents may be more favorable during postoperative management of drainage tube. What is more, internal stents could reduce the digestive fluid loss and benefit the digestive function.
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Conductos Pancreáticos/cirugía , Fístula Pancreática/fisiopatología , Pancreaticoduodenectomía/efectos adversos , Stents , Anastomosis Quirúrgica/métodos , Drenaje , Humanos , Páncreas/fisiopatología , Páncreas/cirugía , Pancreatectomía/métodos , Conductos Pancreáticos/fisiopatología , Fístula Pancreática/cirugía , Complicaciones Posoperatorias , Resultado del TratamientoRESUMEN
The results of this meta-analysis show that DPPHR should be established as first-line treatment because of lower level of severe early postoperative complications, maintenance of endocrine pancreatic functions, shortening of postoperative hospitalization time, and increase of quality of life compared to pancreaticoduodenectomy.
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Duodeno/cirugía , Páncreas/cirugía , Pancreaticoduodenectomía , Pancreatitis Crónica/cirugía , Duodeno/fisiopatología , Humanos , Páncreas/fisiopatología , Pancreatitis Crónica/fisiopatología , Periodo Posoperatorio , Calidad de VidaRESUMEN
To date, because of their rarity, the clinicopathological features and surgical outcomes of small bowel adenocarcinomas (SBAs) have been insufficiently explored. We evaluated the clinicopathological features and long-term outcomes of patients who underwent surgery for SBA.This retrospective study (from 1999 to 2016) examined patients with SBA treated surgically at the China National Cancer Center/Cancer Hospital. Clinicopathological features, preoperative evaluation, surgical treatment, and outcome parameters were reviewed and analyzed.Among the 241 patients studied, pancreaticoduodenectomies were performed in 51.0%, partial resection in 24.5%, palliative bypass surgery in 23.7%, and abdominal exploration in 0.8% of the patients. Majority of the patients were diagnosed at an advanced disease stage, and the duodenum was the most common tumor site. Postoperative complications occurred in 44.4% of the patients. Median overall and progression-free survival rates were 22.0 and 13.0 months, respectively. The 5-year overall and progression-free survival rates for patients with duodenal adenocarcinoma were 30.2% and 21.7%, respectively. Duodenal adenocarcinomas, lymph node metastases, distant metastases, poor differentiation, and lymphovascular invasion were associated with poor overall survival outcomes. The 3 factors associated with progression-free survival were the degree of differentiation, lymph node metastases, and distant metastases.Surgery remains the mainstay of treatment for SBA. A poor prognosis could be owing to the site, metastasis, differentiation, and lymphovascular invasion; however, the prognosis may improve through early diagnosis and operation.
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Adenocarcinoma/fisiopatología , Adenocarcinoma/cirugía , Neoplasias Intestinales/fisiopatología , Neoplasias Intestinales/cirugía , Adenocarcinoma/diagnóstico , Adulto , Anciano , Procedimientos Quirúrgicos del Sistema Digestivo , Supervivencia sin Enfermedad , Femenino , Humanos , Neoplasias Intestinales/diagnóstico , Intestino Delgado , Estimación de Kaplan-Meier , Metástasis Linfática , Masculino , Persona de Mediana Edad , Análisis Multivariante , Estudios Retrospectivos , Resultado del Tratamiento , Adulto JovenRESUMEN
RATIONALE: Perivascular epithelial cell tumors (PEComas) of the pancreas are rare mesenchymal tumors and, to our knowledge, only 20 cases have been reported to date. PATIENT CONCERNS: We report a 43-year-old female who presented with upper abdominal pain for 1 year. She underwent an exploratory laparotomy at a local hospital, which failed to resect the tumor. Five months later, she came to the Chinese National Cancer Center for surgery. Preoperative imaging revealed an 11.5-cm-sized mass located in the head of the pancreas. At the microscopic level, the tumor was composed of epithelioid and spindle cells possessing clear to focally granular eosinophilic cytoplasm, which grew in a nested and alveolar pattern around blood vessels. The tumor cells showed immunoreactivity for human melanoma black 45 (HMB-45), but did not express epithelial or endocrine markers. DIAGNOSES: Pancreatic PEComa. INTERVENTIONS: Pancreaticoduodenectomy, partial hepatectomy, and vascular replacement were performed. After the surgery, the patient received 4 cycles of chemotherapy. OUTCOMES: The patient is free of recurrence and metastasis 1.5 years after surgical resection. LESSONS: PEComa should be recognized as a preoperative differential diagnosis of pancreatic tumors. For treatment, removal of the tumor should be attempted, and in the case of tumors with malignant tendencies, the addition of chemotherapy should be considered.
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Neoplasias Pancreáticas/diagnóstico , Neoplasias de Células Epitelioides Perivasculares/diagnóstico , Adulto , Diagnóstico Diferencial , Femenino , Humanos , Páncreas/diagnóstico por imagen , Páncreas/efectos de los fármacos , Páncreas/patología , Páncreas/cirugía , Neoplasias Pancreáticas/tratamiento farmacológico , Neoplasias Pancreáticas/cirugía , Neoplasias de Células Epitelioides Perivasculares/tratamiento farmacológico , Neoplasias de Células Epitelioides Perivasculares/cirugíaRESUMEN
OBJECTIVE: We aimed to compare the two most commonly used pancreatico-jejunostomy reconstruction techniques-duct-to-mucosa and invagination. METHODS: Databases, including MEDLINE, EMBASE, Cochrane Library, and several clinical trial registration centers were searched. Randomized controlled trials that compared duct-to-mucosa and invagination pancreaticojejunostomy techniques after pancreaticoduodenectomy were included and analyzed. RESULTS: In total, seven RCTs were included, involving 850 patients. The difference in postoperative pancreatic fistula rate between the duct-to-mucosa and invagination pancreaticojejunostomy was not significant (RR = 1.03, 95% CI = 0.76-1.39, P = 0.86). There was no significant difference in clinically relevant postoperative pancreatic fistula between the two groups (RR = 0.78, 95% CI = 0.15-3.96, P = 0.77). The overall morbidity, overall mortality, delayed gastric emptying, intra-abdominal collection, reoperation rate, and length of hospital stay between the two groups were not significantly different. Sensitivity analysis showed that the meta-analysis was stable. Further, no significant publication bias was seen. CONCLUSIONS: Duct-to-mucosa and invagination pancreaticojejunostomy techniques after pancreaticoduodenectomy were comparable in terms of postoperative pancreatic fistula incidence and other parameters.
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Enfermedades Pancreáticas/complicaciones , Pancreaticoduodenectomía/efectos adversos , Pancreatoyeyunostomía , Complicaciones Posoperatorias/diagnóstico , Complicaciones Posoperatorias/cirugía , Humanos , Tiempo de Internación , Oportunidad Relativa , Enfermedades Pancreáticas/cirugía , Pancreaticoduodenectomía/métodos , Pancreatoyeyunostomía/métodos , Complicaciones Posoperatorias/mortalidad , Sesgo de Publicación , Tasa de Supervivencia , Resultado del TratamientoRESUMEN
RATIONALE: Sarcomatoid carcinoma is an extremely rare lesion in the common bile duct (CBD). PATIENT CONCERNS: We present a case of sarcomatoid carcinoma of the distal CBD in a 51-year-old woman who presented with jaundice and abdominal pain. Whipple's operation was performed successfully. Microscopically, the tumor was a poorly differentiated carcinoma containing a component of sarcoma-like differentiation. The tumor cells displayed spindle-shaped nuclei with occasional mitotic figures. Cytokeratin (CK) 7, CK19, CK18, and pan-CK (AE1/AE3) staining was positive on immunohistochemistry. Vimentin and carcinoembryonic antigen (CEA) staining were also positive. DIAGNOSES: Sarcomatoid carcinoma of the distal CBD. INTERVENTIONS: The patient received three cycles of chemotherapy after surgery. OUTCOMES: The patient has experienced no adverse events in the 3 years post-surgery. LESSONS: We present here a case report of sarcomatoid carcinoma of the distal CBD. The patient received chemotherapy after surgery, and was event-free for 3 years post-surgery, suggesting a relatively better prognosis, despite the infiltrative pattern of the tumor.
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Carcinoma/patología , Neoplasias del Conducto Colédoco/patología , Conducto Colédoco/patología , Carcinoma/diagnóstico por imagen , Carcinoma/cirugía , Neoplasias del Conducto Colédoco/diagnóstico por imagen , Neoplasias del Conducto Colédoco/cirugía , Endosonografía , Femenino , Humanos , Persona de Mediana Edad , Tomografía Computarizada por Rayos XRESUMEN
The effects of alcohol drinking and smoking on pancreatic ductal adenocarcinoma (PDAC) mortality are contradictory. Individuals who were diagnosed as PDAC and hospitalized at the China National Cancer Center between January 1999 and January 2016 were identified and included in the study. Ultimately, 1783 consecutive patients were included in the study. Patients were categorized as never, ex-drinkers/smokers or current drinkers/smokers. Hazard ratios (HRs) of all-cause mortality and 95% confidence intervals (CIs) were estimated using Cox proportional hazards models. Compared with never drinkers, the HRs were 1.25 for ever drinkers, 1.24 for current drinkers, and 1.33 for ex-drinkers (trend P = 0.031). Heavy drinking and smoking period of 30 or more years were positive prognostic factors for PDAC. For different smoking and alcohol drinking status, only subjects who are both current smokers and current drinkers (HR, 1.45; 95% CI, 1.03-2.05) were associated with reduced survival after PDAC compared to those who were never smokers and never drinkers. Patients who are alcohol drinkers and long-term smokers before diagnosis have a significantly higher risk of PDAC mortality. Compared to those who neither smoker nor drink, only patients who both smokers and drinkers were associated with reduced survival from PDAC.
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Consumo de Bebidas Alcohólicas , Carcinoma Ductal Pancreático/mortalidad , Neoplasias Pancreáticas/mortalidad , Fumar , Adulto , Anciano , Anciano de 80 o más Años , Consumo de Bebidas Alcohólicas/efectos adversos , Carcinoma Ductal Pancreático/diagnóstico , Carcinoma Ductal Pancreático/epidemiología , Femenino , Humanos , Estimación de Kaplan-Meier , Masculino , Persona de Mediana Edad , Neoplasias Pancreáticas/diagnóstico , Neoplasias Pancreáticas/epidemiología , Vigilancia en Salud Pública , Estudios Retrospectivos , Fumar/efectos adversosRESUMEN
BACKGROUND: Small bowel tumors are relatively rare. Accumulation of data regarding their clinical presentation, pathologic features, prognostic factors, treatment modalities, and outcome has been an issue. We summarize the clinicopathologic features and evaluate the long-term outcome of patients with small bowel tumors who underwent surgery. METHODS: This is a retrospective study of medical records of 456 patients with small bowel tumors treated surgically at a Cancer Hospital between 1999 and 2016. RESULTS: The study included 275 males (60.3%) and 181 females (39.7%). Small bowel tumors were difficult to diagnose because of non-specific symptoms. The most common symptoms were alimentary symptoms (56.8%) and abdominal pain (37.3%). Final histopathology revealed 241 adenocarcinomas (52.9%), 153 gastrointestinal stromal tumors (GISTs; 33.6%), 16 neuroendocrine tumors (NETs; 3.5%), and 46 other types of tumors (10.1%). The 456 surgeries performed included 153 pancreaticoduodenectomies, 241 limited duodenum resections, 60 palliative bypass surgeries, and 2 abdominal explorations. The 5-year overall survival and progression-free survival rates for patients with small bowel tumor were 57.2% and 44.6%, respectively. Adenocarcinomas resulted in the worst overall survival compared to GISTs or NETs, and tumors with duodenal location resulted in a worse survival compared to those with non-duodenal location. CONCLUSION: Surgery is the mainstay of treatment for small bowel tumors. Adenocarcinomas and duodenal involvement seem to contribute to poor outcomes.
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Neoplasias Intestinales/cirugía , Intestino Delgado/cirugía , Adenocarcinoma/cirugía , Adulto , Anciano , Supervivencia sin Enfermedad , Femenino , Tumores del Estroma Gastrointestinal/cirugía , Humanos , Neoplasias Intestinales/mortalidad , Neoplasias Intestinales/patología , Masculino , Persona de Mediana Edad , Tumores Neuroendocrinos/cirugía , Estudios RetrospectivosRESUMEN
Halide perovskites have recently been investigated for various solution-processed optoelectronic devices. The majority of studies have focused on using intrinsic halide perovskites, and the intentional incoporation of dopants has not been well explored. In this work, we discovered that small alkali ions, including lithium and sodium ions, could be electrochemically intercalated into a variety of halide and pseudohalide perovskites. The ion intercalation caused a lattice expansion of the perovskite crystals and resulted in an n-type doping of the perovskites. Such electrochemical doping improved the conductivity and changed the color of the perovskites, leading to an electrochromism with more than 40% reduction of transmittance in the 450-850 nm wavelength range. The doped perovskites exhibited improved electron injection efficiency into the pristine perovskite crystals, resulting in bright light-emitting diodes with a low turn-on voltage.
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AIM: To evaluate the association of body mass index (BMI) with the overall survival of pancreatic ductal adenocarcinoma (PDAC) patients. METHODS: A retrospective analysis of PDAC patients diagnosed in the National Cancer Center of China between January 1999 and December 2014 was performed. These patients were categorized into four BMI groups (< 18.5, 18.5-22.9, 23-27.4 and ≥ 27.5 kg/m2). χ2 tests for comparison of the proportions of categorical variables, and Student's t-test or Mann-Whitney test for continuous variables were employed. Survival analysis was performed with the Kaplan-Meyer method. Their HRs of mortality and 95%CIs were estimated using the Cox proportional hazards model. RESULTS: With a median age of 59.6 years (range: 22.5-84.6 years), in total 1783 PDAC patients were enrolled in this study. Their mean usual BMI was 24.19 ± 3.53 for the whole cohort. More than half of the patients (59.3%) experienced weight loss during the disease onset and progression. Compared with healthy-weight individuals, newly diagnosed patients who were overweight or obese had more severe weight loss during their disease onset and progression (P < 0.001). Individuals who were overweight or obese were associated with positive smoking history (P < 0.001). A significant difference in comorbidity of diabetes (P = 0.044) and coronary artery disease (P < 0.001) was identified between high BMI and normal-weight patients. After a median follow-up of 8 mo, the survival analysis showed no association between BMI and the overall survival (P = 0.90, n = 1783). When we stratified the whole cohort by pancreatic cancer stage, no statistically significant association between BMI and overall survival was found for resectable (P = 0.99, n = 217), unresectable locally advanced (P = 0.90, n = 316) and metastatic patients (P = 0.88, n = 1250), respectively. The results did not change when we used the BMI at diagnosis. CONCLUSION: Our results showed no significance of BMI for the overall survival of PDAC patients.
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Índice de Masa Corporal , Carcinoma Ductal Pancreático/mortalidad , Neoplasias Pancreáticas/mortalidad , Adulto , Anciano , Anciano de 80 o más Años , Carcinoma Ductal Pancreático/patología , China/epidemiología , Comorbilidad , Enfermedad de la Arteria Coronaria/epidemiología , Diabetes Mellitus/epidemiología , Progresión de la Enfermedad , Femenino , Estudios de Seguimiento , Humanos , Estimación de Kaplan-Meier , Masculino , Persona de Mediana Edad , Estadificación de Neoplasias , Sobrepeso/epidemiología , Neoplasias Pancreáticas/patología , Modelos de Riesgos Proporcionales , Estudios Retrospectivos , Factores de Riesgo , Delgadez/epidemiología , Adulto JovenRESUMEN
Pancreatic hamartoma is an extremely rare, non-neoplastic, mass-forming lesion that may be mistaken for malignancy, and the pre-operative diagnosis is particularly challenging. The published literature contains only 23 cases of pancreatic hamartoma. The majority of the cases reported patients with a single benign tumor-like disease that received a pancreatectomy. Immunohistochemical findings confirmed the diagnosis following surgery. The current study reports the case of a 53-year-old female who presented to the Department of Abdominal Surgery, Chinese Academy of Medical Sciences, Cancer Hospital (Beijing, China), due to abdominal pain. Abdominal magnetic resonance imaging revealed a 22×14-mm mass in the head of the pancreas. The patient was pre-operatively diagnosed with a pancreatic space-occupying lesion, and subsequently underwent a pancreaticoduodenectomy. The post-operative course was uneventful. Histological examination of the resected lesion resulted in a diagnosis of pancreatic hamartoma. There were no signs of recurrence at 55 months post-surgery.
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Charge-carrier injection into an emissive semiconductor thin film can result in electroluminescence and is generally achieved by using a multilayer device structure, which requires an electron-injection layer (EIL) between the cathode and the emissive layer and a hole-injection layer (HIL) between the anode and the emissive layer. The recent advancement of halide perovskite semiconductors opens up a new path to electroluminescent devices with a greatly simplified device structure. We report cesium lead tribromide light-emitting diodes (LEDs) without the aid of an EIL or HIL. These so-called single-layer LEDs have exhibited a sub-band gap turn-on voltage. The devices obtained a brightness of 591â¯197 cdâ¯m-2 at 4.8 V, with an external quantum efficiency of 5.7% and a power efficiency of 14.1 lmâ¯W-1. Such an advancement demonstrates that very high efficiency of electron and hole injection can be obtained in perovskite LEDs even without using an EIL or HIL.