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渗透氢对BCC金属裂纹扩展行为的影响

原子与分子物理学报 2025年第4期42卷 45-52页

作者：朱云蝶赵可可张吉鼎江晓禹西南交通大学力学与航空航天学院成都611756

在氢环境下,氢原子会吸附在金属材料表面.随着时间推移,氢原子会渗透进入金属内部占据空隙位置.氢原子的聚集会导致应力集中,最终进一步影响材料的力学行为.本文通过分子动力学方法研究氢在裂纹尖端行为的力学响应.研究结果表明,裂纹尖... 详细信息

在氢环境下,氢原子会吸附在金属材料表面.随着时间推移,氢原子会渗透进入金属内部占据空隙位置.氢原子的聚集会导致应力集中,最终进一步影响材料的力学行为.本文通过分子动力学方法研究氢在裂纹尖端行为的力学响应.研究结果表明,裂纹尖端吸附的氢降低了原子间的键合力,导致局部应力集中所需的临界外加载荷减小;使得材料在较低的断裂强度条件下发生破坏,并在很大程度上促进了裂纹的扩展.模拟观察到在外加载荷下吸附氢在裂纹尖端的渗透过程,氢原子会聚集在高应力区域,造成材料塑性降低.另外,渗透进材料的氢原子数目会随着计算时间的增加达到一个最大临界值.当施加应变增大,裂纹尖端渗透氢原子数最大临界值和达到临界值的时间会增加.

关键词：分子动力学裂纹扩展氢渗透塑性损失

Phosphatidylinositol 3-kinase/Akt pathway regulates hepatic stellate cell apoptosis

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World Journal of Gastroenterology 2008年第33期14卷 5186-5191页

作者： Yan Wang xiao-yu jiang Li Liu Hui-Qing jiang Department of Gastroenterology The Second Hospital of Hebei Medical University The Hebei Institute of Gastroenterology Shijiazhuang 050000 Hebei Province China Hebei Medical University Shijiazhuang 050017 Hebei Province China

AIM: To investigate the role of phosphatidylinositol 3-kinase (PI 3-K)/Akt signaling pathway in the balance of HSC activation and apoptosis in rat hepatic stellate cells (HSC). METHODS: An activated HSC cell line was used in this study. LY 294002, the PI 3-K/Akt signal pathway block-er was used to investigate the molecular events on apoptosis in HSC and to interpret the role of this path-way in HSC apoptosis. Immunocytochemistry, Western blot and reverse transcription polymerase chain reac-tion (RT-PCR) analysis were applied to detect the ex-pression of PI 3-K, and simultaneously phosphorylated-Akt (p-Akt) and total-Akt were determined by Western blot. The HSC apoptosis was examined by annexin-V/ propidium iodide double-labelled flow cytometry and transmission electron microscopy. RESULTS: The apoptosis rates in LY 294002 (30.82% ± 2.90%) and LY 294002 + PDGF-BB (28.16% ± 2.58%) groups were signif icantly increased compared with those of control (9.02% ± 1.81%) and PDGF-BB (4.35% ± 1.18%). PDGF-BB augmented PI 3-K and p-Akt expres-sion. LY 294002 signif icantly reduced the contents of PI 3-K and p-Akt. mRNA transcription evaluated by RT-PCR showed similar tendencies as protein expression. CONCLUSION: Inhibition of PI 3-K/Akt signaling path-way induces apoptosis in HSC.

关键词： Hepatic fibrosis Hepatic stellate cells Phosphatidylinositol 3-kinase Akt Cell apoptosis

Prostaglandin F_(2α)synthase promotes oxaliplatin resistance in colorectal cancer through prostaglandin F_(2α)-dependent and F_(2α)-independent mechanism

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World Journal of Gastroenterology 2023年第39期29卷 5452-5470页

作者： Yi-Jun Wang xiao-Li Xie Hong-Qun Liu Hui Tian xiao-yu jiang Jiu-Na Zhang Sheng-Xiong Chen Ting Liu Shu-Ling Wang Xue Zhou xiao-Xu Jin Shi-Mao Liu Hui-Qing jiang Department of Gastroenterology The Second Hospital of Hebei Medical UniversityShijiazhuang 050000Hebei ProvinceChina Liver Unit University of CalgaryCalgary T1W0K6Canada Department of Gastroenterology The Affiliated Hospital of Hebei Engineering UniversityHandan 056000Hebei ProvinceChina Department of Hepatobiliary Surgery The Second Hospital of Hebei Medical UniversityShijiazhuang 050000Hebei ProvinceChina Department of Gastroenterology The First Hospital of Hebei Medical UniversityShijiazhuang 050000Hebei ProvinceChina Department of Gastroenterology Hebei Youfu HospitalShijiazhuang 050000Hebei ProvinceChina

BACKGROUND Oxaliplatin(Oxa)is the first-line chemotherapy drug for colorectal cancer(CRC),and Oxa resistance is crucial for treatment *** F_(2α)synthase(PGF 2α)(PGFS),an enzyme that catalyzes the production of PGF_(2α),is involved in the proliferation and growth of a variety of ***,the role of PGFS in Oxa resistance in CRC remains *** To explore the role and related mechanisms of PGFS in mediating Oxa resistance in *** The PGFS expression level was examined in 37 pairs of CRC tissues and paracancerous tissues at both the mRNA and protein *** or knockdown of PGFS was performed in CRC cell lines with acquired Oxa resistance(HCT116-OxR and HCT8-OxR)and their parental cell lines(HCT116 and HCT8)to assess its influence on cell proliferation,chemoresistance,apoptosis,and DNA *** determination of the underlying mechanisms,CRC cells were examined for platinum-DNA adducts and reactive oxygen species(ROS)levels in the presence of a PGFS inhibitor or its *** Both the protein and mRNA levels of PGFS were increased in the 37 examined CRC tissues compared to the adjacent normal *** induced PGFS expression in the parental HCT116 and HCT8 cells in a dosedependent ***,overexpression of PGFS in parental CRC cells significantly attenuated Oxainduced proliferative suppression,apoptosis,and DNA *** contrast,knockdown of PGFS in Oxa-resistant HCT116 and HCT8 cells(HCT116-OxR and HCT8-OxR)accentuated the effect of Oxa treatment in vitro and in *** addition of the PGFS inhibitor indomethacin enhanced the cytotoxicity caused by *** with the PGFS-catalyzed product PGF_(2α)reversed the effect of PGFS knockdown on Oxa ***,PGFS inhibited the formation of platinum-DNA adducts in a PGF_(2α)-independent ***_(2α)exerts its protective effect against DNA damage by reducing ROS *** PGFS promotes resistance to Oxa in CRC via both PGF_(

关键词： Prostaglandin F_(2α)synthase Colorectal cancer Oxaliplatin Drug resistance DNA damage

Y-box binding protein 1 augments sorafenib resistance via the PI3K/Akt signaling pathway in hepatocellular carcinoma

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World Journal of Gastroenterology 2021年第28期27卷 4667-4686页

作者： Ting Liu xiao-Li Xie Xue Zhou Sheng-Xiong Chen Yi-Jun Wang Lin-Ping Shi Shu-Jia Chen Yong-Juan Wang Shu-Ling Wang Jiu-Na Zhang Shi-Ying Dou xiao-yu jiang Ruo-Lin Cui Hui-Qing jiang Department of Gastroenterology The Second Hospital of Hebei Medical UniversityShijiazhuang 050000Hebei ProvinceChina Department of Hepatobiliary Surgery The Second Hospital of Hebei Medical UniversityShijiazhuang 050000Hebei ProvinceChina Department of Gastroenterology Hebei General HospitalShijiazhuang 050000Hebei ProvinceChina Department of Gastroenterology Shijiazhuang People’s HospitalShijiazhuang 050000Hebei ProvinceChina Department of Infectious Diseases The Second Hospital of Hebei Medical UniversityShijiazhuang 050000Hebei ProvinceChina

BACKGROUND Sorafenib is the first-line treatment for patients with advanced hepatocellular carcinoma(HCC).Y-box binding protein 1(YB-1)is closely correlated with tumors and drug ***,the relationship between YB-1 and sorafenib resistance and the underlying mechanism in HCC remain *** To explore the role and related mechanisms of YB-1 in mediating sorafenib resistance in *** The protein expression levels of YB-1 were assessed in human HCC tissues and adjacent nontumor ***,we constructed YB-1 overexpression and knockdown hepatocarcinoma cell lines with lentiviruses and stimulated these cell lines with different concentrations of ***,we detected the proliferation and apoptosis in these cells by terminal deoxynucleotidyl transferase dUTP nick end labeling,flow cytometry and Western blotting *** also constructed a xenograft tumor model to explore the effect of YB-1 on the efficacy of sorafenib in ***,we studied and verified the specific molecular mechanism of YB-1 mediating sorafenib resistance in hepatoma cells by digital gene expression sequencing(DGE-seq).RESULTS YB-1 protein levels were found to be higher in HCC tissues than in corresponding nontumor ***-1 suppressed the effect of sorafenib on cell proliferation and ***,the efficacy of sorafenib in vivo was enhanced after YB-1 was knocked ***,KEGG pathway enrichment analysis of DGEseq demonstrated that the phosphoinositide-3-kinase(PI3K)/protein kinase B(Akt)signaling pathway was essential for the sorafenib resistance induced by ***,YB-1 interacted with two key proteins of the PI3K/Akt signaling pathway(Akt1 and PIK3R1)as shown by searching the BioGRID and HitPredict ***,YB-1 suppressed the inactivation of the PI3K/Akt signaling pathway induced by sorafenib,and the blockade of the PI3K/Akt signaling pathway by LY294002 mitigated YB-1-induced sorafenib *** Overall,we con

关键词： Y-box binding protein 1 Hepatocellular carcinoma Sorafenib Drug resistance Phosphoinositide-3-kinase/protein kinase B

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用于多文档文摘句排序的改进MO算法

华南理工大学学报（自然科学版） 2008年第9期36卷 43-47,70页

作者：蒋效宇樊孝忠陈康北京理工大学计算机科学技术学院北京100081

针对CO和MO文摘句排序算法的缺陷,提出了一种将局部主题间的内聚度与MO算法相结合进行文摘句排序的新方法.在统计局部主题间相对位置的基础上,建立它们之间的关系有向图并计算其内聚度;排序过程中每从有向图中输出一个顶点,便从剩余顶... 详细信息

针对CO和MO文摘句排序算法的缺陷,提出了一种将局部主题间的内聚度与MO算法相结合进行文摘句排序的新方法.在统计局部主题间相对位置的基础上,建立它们之间的关系有向图并计算其内聚度;排序过程中每从有向图中输出一个顶点,便从剩余顶点中查找与其具有最大内聚度的顶点,若该内聚度大于阈值,则将这两个顶点所代表的局部主题文摘句置于摘要中相邻的位置.实验结果表明,该算法排序生成的文摘更具连贯性和可读性.

关键词：人工智能多文档文摘局部主题句子排序

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轮轨接触表面有液态介质时的接触问题研究

工程力学 2005年第2期22卷 27-32页

作者：江晓禹金学松西南交通大学应用力学与工程系四川成都610031 西南交通大学牵引动力国家重点实验室四川成都610031

采用接触单元方法,结合初应力法,对于具有表面微观粗糙度和有液态介质存在于轮轨接触表面的弹塑性接触问题进行了研究,获得了轮轨表面接触压力分布、应力分布等结果。结果表明,它们都存在不同程度的峰值,且这些峰值比Hertzian 接触压力... 详细信息

采用接触单元方法,结合初应力法,对于具有表面微观粗糙度和有液态介质存在于轮轨接触表面的弹塑性接触问题进行了研究,获得了轮轨表面接触压力分布、应力分布等结果。结果表明,它们都存在不同程度的峰值,且这些峰值比Hertzian 接触压力大许多,这是由于有表面微观粗糙度的存在,接触过程中凸出的部分进入了接触,而凹下的部分还未进入接触所致。对于法向接触压力,总的来说弹性计算结果的峰值比弹塑性计算结果的峰值要大。而且轮轨接触表面无液态介质存在时的弹塑性计算结果的接触压力峰值比有液态介质存在下的弹塑性计算结果的峰值要大,这是由于接触表面有液态介质存在时,在凹下的部位液态介质不易自由流动和不可压缩特性,引起了液态介质承受了压力所致。

关键词：工程力学接触力学数值摸拟液态介质弹塑性

Clinical effects of applying a tourniquet in total knee arthroplasty on blood loss

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Chinese Medical Journal 2010年第21期123卷 3030-3033页

作者： ZHANG Fu-jiang xiao yu LIU Ya-bin TIAN Xu GAO Zhi-guo Department of Orthopaedics Tianjin Hospital Tianjin 300211China

Background Tourniquets used during total knee arthroplasty may lead to many complications. The aim of this study was to determine perioperative blood loss and its clinical relevance in total knee replacement surgery after applying a *** From June 2009 to October 2009, 60 consecutive patients who underwent routine total knee arthroplasty were randomly divided into two groups and were treated with or without a tourniquet （30 patients/group）. There were no significant differences in patient baseline characteristics between the two groups. We compared the two groups of patients in terms of intra- and postoperative bleeding, invisible or visible bleeding, and total blood *** None of the patients showed poor wound healing, lower extremity deep venous thrombosis or other complications. The amount of blood loss during surgery was lower in the tourniquet group than in the control group （P〈0.01）. However, postoperative visible bleeding （P 〈0.05） and occult bleeding （P 〈0.05） were significantly greater in the toumiquet group than in the control group. There was no significant difference in the total amount of blood loss between the two groups （P 〉0.05）.Conclusions Tourniquet can reduce bleeding during total knee replacement surgery, but is associated with greater visible and invisible blood loss.

关键词： blood loss total knee arthroplasty tourniquet

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精细化工废水提标升级改造工程实例

现代化工 2019年第10期39卷 182-185页

作者：江晓宇九江天赐高新材料有限公司江西九江332500

以某精细化工企业废水处理工程为例,介绍了'物化-混凝-厌氧氧化-水解酸化-两级接触氧化—MBR生化处理工艺'处理精细化工废水的工程应用案例,对工程设计及运行经验方面进行分析总结;设计处理水量为600 m3/d,运行结果表明,综合污水CODCr、... 详细信息

以某精细化工企业废水处理工程为例,介绍了'物化-混凝-厌氧氧化-水解酸化-两级接触氧化—MBR生化处理工艺'处理精细化工废水的工程应用案例,对工程设计及运行经验方面进行分析总结;设计处理水量为600 m3/d,运行结果表明,综合污水CODCr、NH3-N、SS的去除率分别达到97. 8%、79. 2%、90. 6%。出水口各项指标均可满足GB 8978—1996《污水综合排放标准》中的一级排放标准。

关键词：厌氧水解酸化接触氧化 MBR

Fibroblast growth factor-4 and hepatocyte growth factor induce differentiation of human umbilical cord blood-derived mesenchymal stem cells into hepatocytes

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World Journal of Gastroenterology 2005年第47期11卷 7461-7465页

作者： Xin-Qin Kang Wei-Jin Zang Li-Jun Bao Dong-Ling Li Tu-Sheng Song xiao-Li Xu xiao-jiang yu Department of Genetics and Molecular Biology Mcclical School of Xi'an Jiaotong UniversityXi'an 710061 Shaanxi Province China Department of Pharmacology Key Laboratory of Environment and Genes Related to Diseases of Ministry of Education School of Medicine Xi'an Jiaotong University Xi'an 710061 Shaanxi Province China Department of Obstetrics and Gynecology First Hospital of Xi'an Jiaotong University Xi'an 710061 Shaanxi Province China

AIM： To investigate the differentiation of human umbilical cord blood （HUCB）-derived mesenchymal stem cells （MSCs） into hepatocytes by induction of fibroblast growth factor-4 （FGF-4） and hepatocyte growth factor （HGF）, and to find a new source of cell types for therapies of hepatic diseases. METHODS： MSCs were isolated by combining gradient density centrifugation with plastic adherence. When HUCB-derived MSCs reached 70% confluence, they were cultured in Iscove modified Dulbecco medium （IMDM） supplemented with 10 mL/L FBS, 20 ng/mL HGF and 10 ng/mL FGF-4. The medium was changed every 4 d and stored for albumin, alpha-fetoprotein （AFP） and urea assay. Expression of CK-18 was detected by immunocytochemistry. Glycogen storage in hepatocytes was determined by PAS staining. RESULTS： By combining gradient density centrifugation with plastic adherence, we could isolate MSCs from 25.6% of human umbilical cord blood. When MSCs were cultured with FGF-4 and HGF, approximately 63.6% of cells became small, round and epithelioid on d 28 by morphology. Compared with the control, the level of AFP increased significantly from d 12 to 18.20：1=1.16 μg/L （t = 2.884, P〈0.05） in MSCs cultured with FGF-4 and HGF, and was higher （54.28±3.11 μg/L） on d 28 （t = 13.493, P〈0.01）. Albumin increased significantly on d 16 （t = 6.68, P〈0.01） to 1.02±0.15 μg/mL, and to 3.63±0.30 μg/mL on d 28 （t = 11.748, P〈0.01）. Urea （4.72±1.03 μmol/L） was detected on d 20 （t = 4.272, P〈0.01）, and continued to increase to 10.28±1.06　μmol/L on d 28 （t = 9.276, P〈0.01）. Cells expressed CK-18 on d 16. Glycogen storage was observed on d 24. CONCLUSION： HUCB-derived MSCs can differentiate into hepatocytes by induction of F-GF-4 and HGF. HUCB derived MSCs are a new source of cell types for cell transplantation therapy of hepatic diseases.

关键词： Mesenchymal stem cell Differentiation Hepatocyte