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World Journal of Gastroenterology 2016年第22期22卷 5293-5296页

作者： Min-Er Zhong Bei-Zhan Niu Wu-Yang Ji Bin Wu depart-ment of general surgery Peking Union Medical College Hospital

We report on a patient diagnosed with PeutzJeghers syndrome(PJS) with synchronous rectal cancer who was treated with laparoscopic restorative proctocolectomy with ileal pouch-anal anastomosis(IPAA). PJS is an autosomal dominant syndrome characterized by multiple hamartomatous polyps in the gastrointestinal tract, mucocutaneous pigmentation, and increased risks of gastrointestinal and nongastrointestinal cancer. This report presents a patient with a 20-year history of intermittent bloody stool, mucocutaneous pigmentation and a family history of PJS, which together led to a diagnosis of PJS. Moreover, colonoscopy and biopsy revealed the presence of multiple serried giant pedunculated polyps and rectal adenocarcinoma. Currently, few options exist for the therapeutic management of PJS with synchronous rectal cancer. For this case, we adopted an unconventional surgical strategy and ultimately performed laparoscopic restorative proctocolectomy with IPAA. This procedure is widely considered to be the first-line treatment option for patients with ulcerative colitis or familial adenomatous polyposis. However, there are no previous reports of treating PJS patients with laparoscopic IPAA. Since the operation, the patient has experienced no further episodes of gastrointestinal bleeding and has demonstrated satisfactory bowel control. Laparoscopic restorative proctocolectomy with IPAA may be a safe and effective treatment for patients with PJS with synchronous rectal cancer.

关键词： Peutz-Jeghers syndrome Laparoscopy Ileal pouch-anal anastomosis Restorative proctocolectomy Multiple polyps in gastrointestinal tract

Extreme drought triggers parallel shifts in wood anatomical and physiological traits in upper treeline of the Mediterranean Andes

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Ecological Processes 2024年第01期13卷 132-143页

作者： Luiz Santini Jr. Dylan Craven Daigard Ricardo Ortega Rodriguez Manolo Trindade Quintilhan Stephanie Gibson-Carpintero Cristina Aravena Torres Fidel A.Roig Ariel A.Mu?oz Alejandro Venegas-Gonzalez Hémera Centro de Observación de la Tierra Universidad Mayor GEMA Center for Genomics Ecology and Environment Universidad Mayor Data Observatory Foundation ANID Technology Center depart-ment of Forest Sciences ESALQ-University of Sao Paulo department of Plant Biology Institute of Biology University of Campinas Instituto de Geografía Universidad Nacional Autónoma de México (UNAM) Argentine Institute of Nivology Glaciology and Environmental Sciences(IANIGLA CONICET ) Institute of Geography Pontificia Universidad Católica de Valparaíso Instituto de Ciencias Agroalimentarias Animales y Ambientales (ICA3) Universidad de O'Higgins

Background Treeline ecotones of Mediterranean ecoregions have been affected by the increasing intensity and severity of droughts. Even though the effect of droughts on forest dynamics has been widely documented, knowledge is relatively scarce of how extreme climate episodes affect the hydraulic structure and, therefore, the phys-iology of woody plants. The Mediterranean Andes have experienced an uninterrupted period of drought since 2010, including an extremely dry year in 2019 with approximately 80% rainfall deficit. Here, we investigated shifts in wood anatomical and physiological traits of Kageneckia angustifolia, an endemic treeline species, in response to this drought *** We evaluated the xylem plasticity of three K. angustifolia populations across their natural distribution(31–35° SL) based on anatomical(vessel structure and distribution) and physiological(intrinsic water-use efficiency) variables in the tree rings. We focused on the period 2000–2020 that corresponds to before the megadrought(2000–2007),(ii) megadrought(2008–2018) and(iii) hyperdrought(2019–2020). The variables were annualized and analyzed by linear mixed-effects *** Our results provide insights to the anatomical and physiological mechanisms underlying the resilience of treeline forests to persistent droughts in central Chile. We found that the extreme drought in 2019–2020 triggered shifts in vessel size and frequency that increased hydraulic safety. These significant shifts in vessel traits occurred in parallel with a decrease in pit aperture area and an increase in water-use efficiency, further increasing the resilience of K. angustifolia to extreme drought *** Our results revealed coordinated shifts in vessel size and frequency and water-use efficiency in response to the megadrought, thereby reducing vulnerability to hydraulic failure. The apparent resilience of K. angustifolia to extreme droughts suggests that this adaptation to drought stress may incre

关键词： Dendro-anatomy Kageneckia angustifolia Xylem vulnerability Drought Climate change

Electrocrystallization nucleation and growth of NiFe alloys on brass substrate

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中国有色金属学会会刊：英文版 2005年第4期15卷 897-901页

作者：张昭 depart ment of Chemistry Zhejiang University

The electrocrystalliztion nucleation and growth process of Ni-Fe alloy was studied using cyclic voltammetry and chronoamperometry. The results show that, in the case of high deposition overpotential, the nucleation/growth process of Ni-Fe binary alloy is 3-D instantaneous, and the growth rate of the previously formed nuclei increases with overpotential. However, at low overpotential, no distinguished nucleation current can be ***, the discrepancy between the experimental non-dimensional variables(I/Im)2 and those calculated from the theoretical model was elucidated in the light of the molecular orbital theorem.

关键词： NiFe合金电镀工艺黄铜伏安法沉积作用

Effects of surface modification on electrochemical performance of MnO_2

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中国有色金属学会会刊：英文版 2005年第4期15卷 944-948页

作者：刘立清王建明范玉凯王国光张鉴清 depart ment of Chemistry Zhejiang University

The MnO2 samples coated with Ca（OH）2 were prepared by a liquid-phase surface treatment method. The physical properties of the samples were examined by SEM, EDAX and chemical analysis, and their electrochemical performances were investigated by means of galvanostatic charge-discharge, cyclic voltammetry and electrochemical impedance spectroscopy （EIS）. The SEM results show that the samples coated with Ca（OH）2 display a porous surface structure. The electrochemical experiments indicate that the surface modification decreases the polarization of MnO2 electrodes and improves their discharge potentials and discharge capacities.

关键词： MnO2 SEM 电化学光谱学化学电源

ZrB_2/Al_2O_3 composite powders prepared by self-propagating high-temperature synthesis

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中国有色金属学会会刊：英文版 2005年第4期15卷 851-854页

作者：于志强杨振国 depart ment of Material Science Fudan University

Self-propagating high-temperature synthesis（SHS） method was used to synthesize ZrB2/Al2O3 composite powders from B2O3-ZrO2-Al system. X-ray diffractometry（XRD） and scanning electron microscopy（SEM） analyses show the presence of ZrB2 and Al2O3 as the primary phases in the composite powders, while the presence of a very small amount of ZrO2 is thought to be unreacted zirconium oxide. Transmission electron microscopy（TEM） and high resolution electron microscopy（HREM） observations of microstructure of the composite powders indicate that the interfaces of ZrB2/Al2O3 bond well without any interfacial reaction products. It is proposed that the good interfacial bonding of composite powders results from the ZrB2 particles crystallizing and growing on the Al2O3 particles surface with surface defects acting as nucleation centers.

关键词： ZrB2/Al2O3 复合材料高温条件合成方法微结构

Synthesis and high-temperature performance of Ti substituted α-Ni(OH)_2

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中国有色金属学会会刊：英文版 2005年第4期15卷 823-827页

作者：刘宏兵向兰金涌 depart ment of Chemical Engineering Tsinghua University

Ti substituted α-Ni（OH）2（c=2.121nm, a =0.307nm） with perfect high-temperature performance was prepared by the co-precipitation method. The effects of Ti addition on the structure and the electrochemical properties were investigated. The results indicate that the substitution of Ti for Ni leads to the conversion of β-Ni（OH）2 to α-Ni（OH）2 and the increase of the inter layer distance along c-axis from 0.464nm to 0.707nm. Infrared study reveals that more anions（SO2-4 and CO2-3 ions） and H2O exist in the Ti substituted α-Ni（OH）2. The discharge capacity of the Ti substituted α-Ni（OH）2 is 210mA·h/g at 20℃ and reaches up to 270mA·h/g at 80℃ owing to the inhibition of the oxygen evolution at high temperature.

关键词： α-Ni(OH)2 钛合成工艺高温条件蓄电池

Histological analysis of human pancreatic carcinoma following irreversible electroporation in a nude mouse model

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World Journal of Gastrointestinal Oncology 2018年第12期10卷 476-486页

作者： Jun-Jun Su Kai Xu Peng-Fei Wang Hao-Yun Zhang Yong-Liang Chen Division of Gastroenterological surgery Depart-ment of SurgeryShanxi Provincial People’s Hospital department of Hepatobiliary surgery Chinese People’s Liberation Army General Hospital

AIM To determine changes in the morphology and function of pancreatic cancer cells after irreversible electroporation(IRE) treatment, and to explore the clinical significance of IRE treatment for pancreatic cancer providing an experimental basis for the clinical application of IRE treatment. METHODS IRE was carried out in an athymic nude mouse model of pancreatic carcinoma generated with human pancreatic cancer cells 1. In therapy groups, IRE electrodes were inserted with 90 pulses per second at 800 V/cm applied to ablate the targeted tumor tissues. Histological assessment of the affected tissue was performed by hematoxylin and eosin staining(HE). Quantification of cell proliferation and apoptosis was performed by evaluating Ki67 and caspase-3 levels, respectively. Flow cytometry was used to assess cell apoptosis. Ultrasound imaging was carried out to evaluate IRE treatment results. Pathological correlation studies showed IRE is effective for the targeted ablation of pancreatic tumors in an orthotopic mouse *** IRE was efficacious in removing tumors in the orthotopic mouse model. The IRE-ablated zone displays characteristics of nude mouse models at different time-points as assessed by hematoxylin and eosin staining. Immunohistochemical analysis of samples from the pancreatic cancer models showed significantly enhanced caspase-3 cleavage and Ki67. Flow cytometry data corroborated the above findings that apoptosis in tumor cells was observed immediately on the first postoperative day, and with time the middle and late stages of apoptosis were observed. For ultrasound imaging studies, the IRE ablation zone became a hyperechoic area due to increasing inflammatory and immunologic cellular contents. CONCLUSION IRE is a promising new approach for pancreatic cancer, with many potential advantages over conventional ablation techniques.

关键词： Irreversible electroporation Pancreatic carcinoma Pathological evaluation Transplantation model Nude mouse

Identification and analysis based on genetic algorithm for proton exchange membrane fuel cell stack

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Journal of Central South University of Technology 2006年第4期13卷 428-431页

作者：李曦曹广益朱新坚卫东 depart ment of Control Science and Engineering Huazhong University of Science and Technolgy depart ment of Automation Shanghai Jiaotong University

The temperature of proton exchange membrane fuel cell stack and the stoichiometric oxygen in cathode have relationship with the performance and life span of fuel cells closely. The thermal coefficients were taken as important factors affecting the temperature distribution of fuel cells and components. According to the experimental analysis, when the stoichiometric oxygen in cathode is greater than or equal to 1.8, the stack voltage loss is the least. A novel genetic algorithm was developed to identify and optimize the variables in dynamic thermal model of proton exchange membrane fuel cell stack, making the outputs of temperature model approximate to the actual temperature, and ensuring that the maximal error is less than 1 ℃. At the same time, the optimum region of stoichiometric oxygen is obtained, which is in the range of 1.8-2.2 and accords with the experimental analysis results. The simulation and experimental results show the effectiveness of the proposed algorithm.

关键词： proton exchange membrane fuel cell genetic algorithm temperature thermal coefficient stoichiometric oxygen

Giant abdominal osteosarcoma causing intestinal obstruction treated with resection and adjuvant chemotherapy

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World Journal of Gastrointestinal surgery 2017年第2期9卷 68-72页

作者： Alexandros Diamantis Grigorios Christodoulidis Dionysia Vasdeki Foteini Karasavvidou Evangelos Margonis Konstantinos Tepetes depart-ment of general surgery University Hospital of Larisa Division of Anatomic Pathology Univer-sity Hospital of Larisa

Extraskeletal osteosarcoma(ESOS)is an uncommon tumor that accounts for 1% of all soft tissue sarcomas and 4% of all osteosarcomas. Its presentation may be atypical,while pain has been described as the most common symptom. Radiological findings include a large mass in the soft-tissues with massive calcifications,but no attachment to the adjacent bone or periosteum. We present the case of a 73-year-old gentle man who presented with a palpable,tender abdominal mass and symptoms of bowel obstruction. Computer tomography images revealed a large space-occupying heterogeneous,hyper dense soft tissue mass involving the small intestine. Explorative laparotomy revealed a large mass in the upper mesenteric root of the small intestine,measuring 22 cm × 12 cm × 10 cm in close proximity with the cecum,which was the cause of the bowel obstruction. Pathology confirmed the diagnosis of an ESOS. ESOS is an uncommon malignant soft tissue tumor with poor prognosis and a 5-year survival rate of less than 37%. Regional recurrence and distant metastasis to lungs,regional lymph nodes and liver can occur within the first three years of diagnosis in a high rate(45% and 65% respectively). Wide surgical resection of the mass followed by adjuvant chemotherapy or radiotherapy has been the treatment of choice.

关键词： Osteosarcoma Sarcoma Extraskeletal Intestinal obstruction Abdominal mass Soft tissue

Extracapsular invasion as a risk factor for disease recurrence in colorectal cancer

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World Journal of Gastroenterology 2011年第15期17卷 2003-2006页

作者： Takaaki Fujii Yuichi Tabe Reina Yajima Satoru Yamaguchi Soichi Tsutsumi Takayuki Asao Hiroyuki Kuwano depart ment of general Surgical Science Graduate School of Medicine Gunma University Gunma 371-8511 Japan

AIM: To evaluate the presence of extracapsular invasion (ECI) in positive nodes as a predictor of disease recurrence disease in colorectal cancer. METHODS: Two hundred and twenty-eight consecutive patients who underwent colorectal resection were identified for inclusion in this study, of which 46 had positive lymph nodes. Among 46 cases with stage Ⅲcolorectal cancer, 16 had ECI at positive nodes and 8 had disease recurrence. The clinical and pathological features of these cases were reviewed. RESULTS: In the univariate analysis, the number of positive lymph nodes and depth of tumor invasion were significantly associated with the presence of ECI at positive nodes. Multivariate analysis demonstrated that only ECI was a predictor of recurrence. The recurrence-free interval differed significantly among patients with ECI at positive ***: Our results suggest that ECI at metastatic nodes can identify which cases are at high risk of short-term disease recurrence in colorectal cancer.

关键词： Extracapsular invasion Lymph node Metastasis Colorectal cancer Risk factor Adjuvant therapy