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热老化对聚偏氟乙烯结构与性能的影响 预览
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作者 李震 卢青针 +3 位作者 尹原超 阎军 岳前进 张晶 《高分子材料科学与工程》 EI CAS CSCD 北大核心 2019年第6期40-44,共5页
采用X射线衍射、傅里叶变换红外光谱、差示扫描量热及力学拉伸等多尺度表征手段研究在130℃高温热老化不同时间(0~60d)对聚偏氟乙烯结构和性能的影响。结果表明,在热老化初期,相当于对样品退火处理,退火处理促进了聚偏氟乙烯非晶相至晶... 采用X射线衍射、傅里叶变换红外光谱、差示扫描量热及力学拉伸等多尺度表征手段研究在130℃高温热老化不同时间(0~60d)对聚偏氟乙烯结构和性能的影响。结果表明,在热老化初期,相当于对样品退火处理,退火处理促进了聚偏氟乙烯非晶相至晶相的转变,样品的结晶完善程度和结晶度明显提高,熔融温度向高温偏移,拉伸强度随之提高,但断裂伸长率下降;随着热老化实验进行,高温诱导结晶区域遭到破坏,样品的结晶度下降,熔融温度略有降低,拉伸强度及断裂伸长率均下降,但在整个热老化过程中,聚偏氟乙烯的晶体结构均得以保留。 展开更多
关键词 聚偏氟乙烯 热老化 结晶结构 力学性能
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高性能可充式锂硒电池多孔分散碳球/硒复合物的合成与表征 预览
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作者 颜军 刘维芳 +2 位作者 陈诚 赵陈浩 刘开宇 《中国有色金属学报:英文版》 SCIE EI CAS CSCD 2018年第9期1819-1827,共9页
为了探索锂硒电池中负载硒的合适材料,以间苯二酚?甲醛树脂作前驱体通过熔融?分散法制备多孔分散碳球/硒复合物。首先,通过将间苯二酚?甲醛树脂碳化,随后用氢氧化钾活化制备得到多孔分散碳球。对3种含有不同质量比的多孔碳球/硒复合物... 为了探索锂硒电池中负载硒的合适材料,以间苯二酚?甲醛树脂作前驱体通过熔融?分散法制备多孔分散碳球/硒复合物。首先,通过将间苯二酚?甲醛树脂碳化,随后用氢氧化钾活化制备得到多孔分散碳球。对3种含有不同质量比的多孔碳球/硒复合物样品进行XRD、拉曼光谱、扫描电镜、BET比表面积法和元素图谱测试。结果表明,硒在复合物样品中含量的不同会形成不同的内部结构,硒在多孔分散碳球/硒复合物中的最佳含量为50%,这种复合物电极在0.2C的电流密度下经过100次循环表现出643.9 mA·h/g的高比容量。 展开更多
关键词 锂硒电池 正极材料 碳球 溶胶凝胶法
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酒精中毒对交通事故重型颅脑外伤患者炎症反应和预后的影响 预览
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作者 严峻 文静 +2 位作者 罗大卿 龚坚 莫立根 《中国现代医学杂志》 2018年第33期57-63,共7页
目的探讨血清酒精浓度(BAC)对交通事故重型颅脑外伤患者炎症反应和预后结果的影响。方法采用前瞻性研究选取2012年1月—2016年12月收治的92例交通事故重型颅脑外伤患者,根据酒精浓度将患者分为BAC阳性组(40例,BAC>0.5‰)和BAC阴性组... 目的探讨血清酒精浓度(BAC)对交通事故重型颅脑外伤患者炎症反应和预后结果的影响。方法采用前瞻性研究选取2012年1月—2016年12月收治的92例交通事故重型颅脑外伤患者,根据酒精浓度将患者分为BAC阳性组(40例,BAC>0.5‰)和BAC阴性组[52例,BAC<0.5‰,将伤情严重程度评分(ISS)≥16和简略受伤标准(AIS)头部AIS≥3的患者纳入该研究]。患者入急诊科采集血标本检测BAC、白细胞介素6(IL-6)、肿瘤坏死因子α(TNF-α)、C反应蛋白(CRP)及白细胞计数水平,收集患者在急诊室或院前急救时的临床资料和生存情况,根据两组不同指标进行统计学分析。结果两组ISS评分和格拉斯哥评分(GCS)比较,差异无统计学意义(P>0.05);BAC阳性组IL-6、TNF-α、CRP及白细胞计数低于BAC阴性组(P<0.05);BAC阳性组收缩压、心率及体温均低于BAC阴性组,而呼吸频率高于BAC阴性组(P<0.05);BAC阳性组输浓缩红细胞较少(P<0.05);两组住院时间比较差异无统计学意义(P>0.05)。两组颅脑外伤的并发症包括单器官衰竭、多器官衰竭及全身炎症反应综合征(SIRS)、脓肿、肺炎和急性呼吸窘迫综合征(ARDS)比较,差异无统计学意义(P>0.05)。结论创伤性脑损伤(TBI)患者中BAC阳性与IL-6、TNF-α、CRP及白细胞计数的下降有相关性,酒精可能对TBI患者单核细胞等免疫细胞具有抑制炎症因子分泌的作用。 展开更多
关键词 创伤性脑损伤 血液酒精浓度 格拉斯哥评分 炎症因子
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HOXD3在乳腺癌细胞干性和化疗耐药性中的作用及机制研究 预览
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作者 何艳霞 闫俊 +3 位作者 李洪滨 张清媛 程绍强 张悦 《中国肿瘤临床》 CSCD 北大核心 2018年第12期614-619,共6页
目的:探讨HOXD3表达对乳腺癌细胞干性的影响,并研究HOXD3表达与乳腺癌细胞化疗耐药的关系。方法:收集2006年1月至2008年12月哈尔滨医科大学附属肿瘤医院87例乳腺癌患者组织标本。采用免疫组织化学染色法检测乳腺癌细胞和组织中HOXD3表... 目的:探讨HOXD3表达对乳腺癌细胞干性的影响,并研究HOXD3表达与乳腺癌细胞化疗耐药的关系。方法:收集2006年1月至2008年12月哈尔滨医科大学附属肿瘤医院87例乳腺癌患者组织标本。采用免疫组织化学染色法检测乳腺癌细胞和组织中HOXD3表达;采用RT-PCR、Western blot和免疫荧光染色法检测HOXD3在顺铂或阿霉素耐药细胞系MDA-MB-231和MDA-MB-435中的表达水平,分析HOXD3过表达对乳腺癌细胞系MDA-MB-231和MDA-MB-435的干细胞生物标志物表达水平的影响;采用MTT法和集落形成实验分析HOXD3在乳腺癌细胞化疗耐药中的作用。结果:乳腺癌组织中HOXD3 m RNA相对表达量显著高于癌旁正常组织,乳腺癌细胞系MDA-MB-231、MDA-MB-435和MCF-7的HOXD3 m RNA相对表达量均高于正常乳腺上皮细胞系MCF-10A(均P〈0.05)。顺铂或阿霉素耐药的细胞系MDA-MB-231和MDA-MB-435的半抑制浓度(half maximal inhibi-tory concentration,IC50)分别为(20.82±0.05)μmol/L和(19.69±0.47)μmol/L,或(32.26±0.23)mmol/L和(26.08±0.55)mmol/L,均高于对应原始细胞系(均P〈0.05);耐药倍数分别为2.47和3.10倍,或1.86和2.08倍。HOXD3过表达MDA-MB-231、MDA-MB-435的肿瘤球体数目、干细胞生物标志物的表达水平均明显增加(均P〈0.05)。结论:HOXD3过表达对乳腺癌细胞干性的维持及化疗耐药性的发生发挥重要的作用,为制定针对肿瘤干细胞的分子靶向治疗提供理论参考。 展开更多
关键词 HOXD3 乳腺癌 肿瘤干细胞 耐药 整合素Β3
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Effects of micro-alloying and production process on precipitation behaviors and mechanical properties of HRB600
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作者 Hong-bo Pan Meng-jiao Zhang +4 位作者 Wei-ming Liu Jun Yan Hui-ting Wang Chang-sheng Xie Zhan Guo 《钢铁研究学报:英文版》 SCIE EI CAS CSCD 2017年第5期536-543,共8页
Effects of micro-alloying elements and production process on microstructure,mechanical properties and precipitates of 600 MPa grade rebars were studied by using pilot test,metallographic observation,tensile test,therm... Effects of micro-alloying elements and production process on microstructure,mechanical properties and precipitates of 600 MPa grade rebars were studied by using pilot test,metallographic observation,tensile test,thermodynamic calculation and transmission electron microscopy. The results show that the tested steels are composed of ferrite and pearlite,in which the content range of pearlite is 33%-45%. For vanadium microalloyed steel,interphase precipitation strengthening effect of V can be promoted and the yield strength of tested steels can be increased with increasing V content and decreasing finishing rolling temperature. The temperature of terminated cooling should be more than 700 °C when the water cooling is used. When niobium is added to the steel,more coarse( Nb,V) C,N precipitates are generated at high temperature,so that the solid solubility of precipitated phases of vanadium is reduced and the precipitation strengthening effect of vanadium is weakened. 展开更多
Iodized salt consumption and iodine deficiency status in China: a cross-sectional study 预览
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作者 Lijun Fan Xiaohui Su +8 位作者 Hongmei Shen Peng Liu Fangang Meng Jun Yan Zhenglong Lei Shubin Zhang Yunyou Gu Shoujun Liu Dianjun Sun 《全球健康杂志(英文)》 2017年第2期23-37,共15页
Objective:To monitor iodized salt consumption and evaluate iodine deficiency status in 2014 in China.Materials and Methods:In 2014,a nationwide cross-sectional survey was conducted in 31 provinces (in this study,provi... Objective:To monitor iodized salt consumption and evaluate iodine deficiency status in 2014 in China.Materials and Methods:In 2014,a nationwide cross-sectional survey was conducted in 31 provinces (in this study,provinces,autonomous regions and municipalities in Mainland China were named as provinces).Probability proportional to size sampling method was adopted to recruit children ages 8-10 and pregnant women.47,467 children's and 18,994 pregnant women's urine samples were collected and 47,706 children's thyroid volumes were examined.Iodine content in salt was determined with 46,900 edible salt samples from children's households;urinary iodine concentration (UIC) was tested from children and pregnant women's urine samples;thyroid volume of children was assessed by ultrasound.Results:The national coverage rate of iodized salt and consumption rate of qualified iodized salt were 96.3% and 91.5%,respectively.Median iodine content in iodized salt was 25.2 mg/kg.In 22 of 31 provinces,the provincial coverage rates of iodized salt were over 95%.And consumption rates of qualified iodized salt were more than 90% in 21 provinces.In this study,the national median urinary iodine concentration (MUIC) of children in China was 197.9 μg/L.At the provincial level,MUIC of children in 19 provinces was 100-199 μg/L,which in 12 provinces was 200-299 μg/L.The national MUIC of pregnant women in 2014 was 154.6 μg/L,slightly higher than the lower limit of the WHO criteria for adequate (150-249 μg/L).At the provincial level,MUIC of pregnant women in 18 provinces was 100-149 μg/L,which in 13 provinces was 150-249 μg/L.The national prevalence of goiter among children in 2014 was 2.6%,of which only Shandong province (5.6%) exceeded the national standard (5%).Conclusions:In China,iodine deficiency disorders (IDD) has been eliminated since 2005.And in 2014,the IDD-free status still remained. 展开更多
关键词 iodized SALT median urinary IODINE concentration prevalence of GOITER IODINE deficiency disorders the seventh national survey the coverage RATE of iodized SALT CONSUMPTION RATE of QUALIFIED iodized SALT
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酰胺类杂环烯酮缩胺的合成
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作者 罗大云 崔时胜 +2 位作者 胡兴梅 林军 严胜骄 《有机化学》 SCIE CAS CSCD 北大核心 2017年第1期166-175,共10页
建立了以杂环烯酮缩胺(HKAs)为原料,用芳基异氰酸酯为酰化剂,实现杂环烯酮缩胺选择性酰化.通过该区域选择性反应简洁、快速地合成了一系具有潜在药理活性的酰胺类杂环烯酮缩胺化合物的方法.该方法以六元或七元环杂环烯酮缩胺1~2与芳... 建立了以杂环烯酮缩胺(HKAs)为原料,用芳基异氰酸酯为酰化剂,实现杂环烯酮缩胺选择性酰化.通过该区域选择性反应简洁、快速地合成了一系具有潜在药理活性的酰胺类杂环烯酮缩胺化合物的方法.该方法以六元或七元环杂环烯酮缩胺1~2与芳基异氰酸酯4在1,4-二氧六环溶剂中室温下合成杂环烯酮缩胺α-碳选择性酰基化产物5~6,产率90%~98%;而五元环杂环烯酮缩胺3与芳基异氰酸酯4在1,4-二氧六环溶剂中碳酸铯催化室温下合成杂环烯酮缩胺选择性氮酰基化产物7,产率78%~93%. 展开更多
关键词 杂环烯酮缩胺 异氰酸酯 区域选择性 酰化反应
一步法合成异喹啉酮类化合物 被引量:1
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作者 王保取 孔令斌 +2 位作者 罗琴 林军 严胜骄 《有机化学》 CSCD 北大核心 2017年第11期2972-2977,共6页
建立了一步法简洁、高效合成异喹啉酮类化合物的方法.该方法是利用硝基取代的邻氟苯甲酸甲酯1与杂环烯酮缩胺(HKAs,2)在1,4-二氧六环溶剂中Cs_2CO_3催化下,加热回流反应.从而实现一步合成异喹啉酮类化合物3.该方法具有合成原料易得、... 建立了一步法简洁、高效合成异喹啉酮类化合物的方法.该方法是利用硝基取代的邻氟苯甲酸甲酯1与杂环烯酮缩胺(HKAs,2)在1,4-二氧六环溶剂中Cs_2CO_3催化下,加热回流反应.从而实现一步合成异喹啉酮类化合物3.该方法具有合成原料易得、操作简单、路线简洁等特点. 展开更多
关键词 环境友好 原子经济 杂环烯酮缩胺 异喹啉酮
茚酮并吡咯类化合物的绿色合成 被引量:1
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作者 罗大云 胡兴梅 +2 位作者 资全兴 林军 严胜骄 《有机化学》 CSCD 北大核心 2017年第12期3204-3212,共9页
建立合成茚酮并吡咯类化合物的绿色合成方法,该方法以N-烷基-1-(甲巯基)-2-硝基乙烯胺(1)和水合茚三酮(2)为原料,在乙醇溶剂中无催化剂条件下,加热反应一步法简洁、快速地合成了一系列茚酮并吡咯类化合物.收率91%~98%.该方法具有... 建立合成茚酮并吡咯类化合物的绿色合成方法,该方法以N-烷基-1-(甲巯基)-2-硝基乙烯胺(1)和水合茚三酮(2)为原料,在乙醇溶剂中无催化剂条件下,加热反应一步法简洁、快速地合成了一系列茚酮并吡咯类化合物.收率91%~98%.该方法具有原料易得,操作简单,路线简洁等特点. 展开更多
关键词 N-烷基1-(甲巯基)-2-硝基乙烯 茚三酮 茚酮 吡咯 绿色合成
Clinical study of quality of life of traumatic brain injury patients after decompressive craniectomy and related influencing factors
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作者 Roodrajeetsing Gopaul Zongdang Wei +2 位作者 Jun Yan Fanyong Gong Shaowen Xiao 《中华神经外科杂志(英文)》 2016年第4期201-210,共10页
Intracranial foreign body through the sagittal sinus: case report and review of literature
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作者 Roodrajeetsing Gopaul Wen Shao Xiao +1 位作者 Jun Yan Dang Zong Wei 《中华神经外科杂志(英文)》 2016年第3期共8页
Intraoperative rupture of blood blister-like aneurysm: a case report and review of literature
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作者 Roodrajeetsing Gopaul Wen Shao Xiao +1 位作者 Jun Yan Dang Zong Wei 《中华神经外科杂志(英文)》 2016年第1期共6页
Downregulation of myosin Ⅵ reduced cell growth and increased apoptosis in human colorectal cancer
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作者 Weiqiang You Gewen Tan +5 位作者 Nengquan Sheng Jianfeng Gong Jun Yan Di Chen Huizhen Zhang Zhigang Wang 《生物化学与生物物理学报:英文版》 SCIE CAS CSCD 2016年第5期430-436,共7页
Colorectal 癌症(CRC ) 是世界范围的第三最通常诊断的癌症,与在最后十年稳定地增加的死亡。肌浆球蛋白 VI (MYO6 ) 表示被发现在人的癌房间类型的一些类型被提高,建议它可以是为诊断和后续的敏感 biomarker。在这研究,我们首先使用... Colorectal 癌症(CRC ) 是世界范围的第三最通常诊断的癌症,与在最后十年稳定地增加的死亡。肌浆球蛋白 VI (MYO6 ) 表示被发现在人的癌房间类型的一些类型被提高,建议它可以是为诊断和后续的敏感 biomarker。在这研究,我们首先使用了 Oncomine 数据库在 CRC 纸巾探索 MYO6 的表示,然后构造了指向 MYO6 基因的 RNA 干扰的 plasmid。在指向 MYO6 进 SW1116 房间的 lentivirus 的 transfection 以后,房间生存能力和增长与 3-(4,5-Dimethylthiazol-2-yl ) 被测量 -2,5-diphenyltetrazolium 溴化物和殖民地形成试金。房间周期分发是由流动 cytometry 的 assayed, apoptosis 被 Annexin V 评估。MYO6 表示被量的即时聚合酶链反应和西方的污点分析检测。MYO6 mRNA 是在用公共 Oncomine microarray 数据集的数据采矿的 CRC 纸巾的 upregulated,这被发现。MYO6 的弄空显著地禁止了房间增长和殖民地形成。另外, MYO6 击倒稍微在 G0/G1 阶段逮捕了房间周期,但是显著地随 apoptotic 房间的增加增加了房间的 sub-G1 阶段的比例。这些结果建议 MYO6 可以支持房间生长并且可以为 CRC 的 anticancer 治疗被用作一个潜在的目标。 展开更多
关键词 细胞凋亡 细胞生长 结肠癌 肌球蛋白 ANNEXIN 结直肠癌 聚合酶链反应 细胞周期阻滞
Immunotherapy in human colorectal cancer: challenges and prospective 预览
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作者 Xuan Sun Jian Suo Jun Yan 《世界胃肠病学杂志:英文版》 SCIE CAS 2016年第28期6362-6372,共11页
Human colorectal cancer(CRC) is the third most commonly diagnosed malignancies and the prognosis for patients with recurrent or metastatic disease is extremely poor. Although new chemotherapeutic regimen improves surv... Human colorectal cancer(CRC) is the third most commonly diagnosed malignancies and the prognosis for patients with recurrent or metastatic disease is extremely poor. Although new chemotherapeutic regimen improves survival rates, therapy with better efficacy and less adverse effects is drastically needed. Immunotherapy has been investigated in human CRC for decades with limited success. However, recent developments of immunotherapy, particularly immune checkpoint inhibitor therapy, have achieved promising clinical benefits in many types of cancer and revived the hope for utilizing such therapy in human CRC. In this review, we will discuss important immunological landscape within the CRC microenvironment and introduce immunoscore system to better describe immunophenotyping in CRC. We will also discuss different immunotherapeutic approaches currently utilized in different phases of clinical trials. Some of those completed or ongoing trials are summarized. Finally, we provide a brief prospective on the future human CRC immunotherapy. 展开更多
关键词 IMMUNOTHERAPY Human COLORECTAL cancer ADOPTIVE cell THERAPY Immune CHECKPOINT inhibitor THERAPY Immu
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Midterm outcome after repair of tetralogy of fallot with absent pulmonary valve 预览
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作者 Enshi Wang Jun Yan +1 位作者 Shoujun Li Hao Zhang 《中国循环杂志》 CSCD 北大核心 2016年第z1期共2页
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Stark-Broadened Profiles of the Spectral Line Pα in He Ⅱ Ions
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作者 段斌 Muhammad Abbas Bari +2 位作者 吴泽清 颜君 王建国 《中国物理快报:英文版》 SCIE CAS CSCD 2016年第3期24-27,共4页
We report a systematic method to perform calculations of spectral line broadening parameters in plasmas.This method is applied to calculate Stark-broadening line profiles of Pα(n=4→n = 3) transitions under certain s... We report a systematic method to perform calculations of spectral line broadening parameters in plasmas.This method is applied to calculate Stark-broadening line profiles of Pα(n=4→n = 3) transitions under certain specific plasma conditions,by treating this case as an example.In the framework of the fully relativistic Dirac Rmatrix theory,we calculate the electron-impact broadening operators,which are assumed to be diagonal matrix to simplify the situation.The electric microfield distribution function is calculated by retaining Hooper's formalism.The dipole matrix elements and atomic structure parameters used in these calculations have been obtained from atomic structure GRASP code.Based on this required data,we calculate the Stark-broadened line profiles of the Paschen spectral lines in He Ⅱ ions in a systematic manner.Overall,there is a very good agreement between our calculated Stark-broadened line profiles and other line broadening numerical simulation codes(SimU and MELS).Our reported spectral line-broadening data have real applications in plasma spectroscopy,plasma diagnosis and aiso piay a fundamentai role in plasma modeling. 展开更多
关键词 等离子体模拟 谱线展宽 Stark展宽 原子结构参数 等离子体光谱 等离子体诊断 矩阵理论 对角矩阵
Correlation effects on the fine-structure splitting within the 3d9 ground configuration in highly-charged Co-like ions
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作者 郭学玲 黄敏 +4 位作者 颜君 李双 王凯 司然 陈重阳 《中国物理B:英文版》 SCIE EI CAS CSCD 2016年第1期535-542,共8页
A comprehensive theoretical study of correlation effects on the fine-structure splitting within the ground configuration3d9 of the Co-like Hf45+,Ta46+,W47+,and Au52+ ions is performed by employing the multi-configurat... A comprehensive theoretical study of correlation effects on the fine-structure splitting within the ground configuration3d9 of the Co-like Hf45+,Ta46+,W47+,and Au52+ ions is performed by employing the multi-configuration Dirac-HartreeFock method in the active space approximation.It shows that the core-valence correlation with the inner-core 2p electron is more significant than with the outer 3p and 3s electrons,and the correlation with the 2s electron is also noticeable.The core-core correlation seems to be small and can be ignored.The calculated 2D3/2,5/2 splitting energies agree with the recent electron-beam ion-trap measurements[Phys.Rev.A 83 032517(2011),Eur.Phys.J.D 66 286(2012)]to within the experimental uncertainties. 展开更多
关键词 类钴离子 精细结构 分裂能 HARTREE-FOCK 配置 地面 电子束离子阱 物理测量
Long-term oncologic outcomes of laparoscopic vs open surgery for stages Ⅱ and Ⅲ rectal cancer: A retrospective cohort study 预览 被引量:1
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作者 Zhen-Xu Zhou +13 位作者 Li-Ying Zhao Tian Lin Hao Liu Hai-Jun Deng Heng-Liang Zhu Jun Yan Guo-Xin Li 《世界胃肠病学杂志:英文版(电子版)》 SCIE CAS 2015年第18期5505-5512,共8页
AIM: To evaluate the 5-year survival after laparoscopic surgery vs open surgery for stages Ⅱ and Ⅲ rectal cancer.METHODS:This study enrolled 406 consecutive patients who underwent curative resection for stagesⅡand... AIM: To evaluate the 5-year survival after laparoscopic surgery vs open surgery for stages Ⅱ and Ⅲ rectal cancer.METHODS:This study enrolled 406 consecutive patients who underwent curative resection for stagesⅡandⅢrectal cancer between January 2000 and December 2009[laparoscopic rectal resection(LRR),n=152;open rectal resection(ORR),n=254].Clinical characteristics,operative outcomes,pathological outcomes,postoperative recovery,and 5-year survival outcomes were compared between the two groups.RES... 展开更多
关键词 LAPAROSCOPIC surgery LOCALLY advanced RECTAL cancer Oncologic OUTCOMES
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Antagonism of toll-like receptor 2 attenuates the formation and progression of abdominal aortic aneurysm
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作者 Huimin Yan Bing Cui +6 位作者 Xiaowei Zhang Xiaoming Fu Jun Yan Xiaoxing Wang Xiaoxi Lv Zhong Chen Zhuowei Hu 《药学学报:英文版》 CSCD 2015年第3期176-187,共12页
Abdominal aortic aneurysm(AAA) is an inflammatory vascular disorder with high mortality.Accumulating evidence shows that toll-like receptor 2(TLR2) plays a critical role in the regulation of wound-repairing process af... Abdominal aortic aneurysm(AAA) is an inflammatory vascular disorder with high mortality.Accumulating evidence shows that toll-like receptor 2(TLR2) plays a critical role in the regulation of wound-repairing process after tissue injury.We wondered if TLR2 signaling contributed to the pathogenesis of AAA and that targeting TLR2 would attenuate AAA development and progression.In this study,enhanced expression of TLR2 and its ligands were observed in human AAA tissue.Neutralization of TLR2 protected against AAA development and caused established AAA to regress in mouse models of AAA.In addition,TLR2-deficient mice also failed to develop AAA.The prophylactic and therapeutic effects of blocking TLR2 were accompanied by a significant resolution of inflammation and vascular remodeling,as indicated by the decreased expression or activity of MMP-2/9,α-SMA,inflammatory cytokines,and transcription factors NF-κB,AP-1 and STAT1/3 in AAA tissue.Mechanistically,blocking TLR2 decreased the expression and interaction of TLR2 and several endogenousligands,which diminished chronic inflammation and vascular remodeling in the vascular tissue of AAA.Our studies indicate that the interactions between TLR2 and its endogenous ligands contribute to the pathogenesis of AAA and that targeting TLR2 offers great potential toward the development of therapeutic agents against AAA. 展开更多
Experiment and Simulation of Metal Flow in Multi-stage Forming Process of Railway Wheel
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作者 Xiao-hui SHEN Wei CHEN +2 位作者 Jun YAN Lei ZHANG Jing ZHANG 《钢铁研究学报:英文版》 SCIE CAS CSCD 2015年第1期21-29,共9页
To investigate the metal flow during the railway wheel forming process,experiments and finite element method(FEM)simulation were carried out.An axisymmetric modeling for the wheel rolling process was proposed to predi... To investigate the metal flow during the railway wheel forming process,experiments and finite element method(FEM)simulation were carried out.An axisymmetric modeling for the wheel rolling process was proposed to predict the metal flow in radial direction,by which the whole multi-stage forming process could be simulated in axisymmetric and integral way.The result shows that the axisymmetric simulation method was an effective method to explore the metal flow in radial direction and to analyze the relationships of tools motion during the wheel rolling.The detail information about metal flow in railway wheel forming process was obtained.The metal in the wheel web was from the area near the half radius of the original billet;the chill zone of the billet became an envelope of the rim and part of the web with a maximum thickness of about 6mm below the tread.At the wheel rolling stage,the metal in the rim flowed towards the web;the metal near the surfaces of the conjunction region between the web and rim suffered severe shear deformation. 展开更多
关键词 金属流动 火车车轮 成形过程 多级 实验 仿真 轴对称 有限元法
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