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The Chinese Society of Clinical Oncology(CSCO):Clinical guidelines for the diagnosis and treatment of gastric cancer,2021 被引量:207
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作者 Feng-Hua Wang Xiao-Tian Zhang +31 位作者 Yuan-Fang Li Lei Tang Xiu-Juan Qu Jie-Er Ying Jun Zhang Ling-Yu Sun Rong-Bo Lin Hong Qiu Chang Wang Miao-Zhen Qiu Mu-Yan Cai QiWu Hao Liu Wen-Long Guan Ai-Ping Zhou Yu-Jing Zhang Tian-Shu Liu Feng Bi Xiang-Lin Yuan Sheng-Xiang Rao Yan Xin Wei-Qi Sheng Hui-Mian Xu Guo-Xin Li Jia-Fu Ji Zhi-Wei Zhou Han Liang Yan-Qiao Zhang Jing Jin Lin Shen Jin Li Rui-Hua Xu 《Cancer Communications》 SCIE 2021年第8期747-795,共49页
There exist differences in the epidemiological characteristics,clinicopathological features,tumor biological characteristics,treatment patterns,and drug selections between gastric cancer patients from the Eastern and ... There exist differences in the epidemiological characteristics,clinicopathological features,tumor biological characteristics,treatment patterns,and drug selections between gastric cancer patients from the Eastern and Western countries.The Chinese Society of Clinical Oncology(CSCO)has organized a panel of senior experts specializing in all sub-specialties of gastric cancer to compile a clinical guideline for the diagnosis and treatment of gastric cancer since 2016 and renews it annually.Taking into account regional differences,giving full consideration to the accessibility of diagnosis and treatment resources,these experts have conducted expert consensus judgment on relevant evidence and made various grades of recommendations for the clinical diagnosis and treatment of gastric cancer to reflect the value of cancer treatment and meeting health economic indexes in China.The 2021 CSCO Clinical Practice Guidelines for Gastric Cancer covers the diagnosis,treatment,follow-up,and screening of gastric cancer.Based on the 2020 version of the CSCO Chinese Gastric Cancer guidelines,this updated guideline integrates the results ofmajor clinical studies from China and overseas for the past year,focused on the inclusion of research data from the Chinese population for more personalized and clinically relevant recommendations.For the comprehensive treatment of non-metastatic gastric cancer,attentions were paid to neoadjuvant treatment.The value of perioperative chemotherapy is gradually becoming clearer and its recommendation level has been updated.For the comprehensive treatment of metastatic gastric cancer,recommendations for immunotherapy were included,and immune checkpoint inhibitors fromthird-line to the first-line of treatment for different patient groups with detailed notes are provided. 展开更多
关键词 ADJUVANT chemotherapy Chinese Society of Clinical Oncology(CSCO) diagnosis gastric cancer IMMUNOTHERAPY NEOADJUVANT RADIOTHERAPY surgery targeted therapy
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A complete sequence and comparative analysis of a SARS-associated virus(Isolate BJ01) 被引量:122
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作者 QIN E'de ZHU Qingyu +44 位作者 YU Man FAN Baochang CHANG Guohui SI Bingyin YANG Bao PENG Wenming JIANG Tao LIU Bohua DENG Yongqiang LIU Hong ZHANG Yu WANG Cui LI Yuquan GAN Yonghua LI Xiaoyu L Fushuang TAN Gang CAO Wuchun YANG Ruifu WANG Jian LI Wei XU Zuyuan LI Yan WU Qingfa LIN Wei CHEN Weijun TANG Lin DENG Yajun HAN Yujun LI Changfeng LEI Meng LI Guoqing LI Wenjie L Hong SHI Jianping TONG Zongzhong ZHANG Feng LI Songgang LIU Bin LIU Siqi DONG Wei WANG Jun Gane K-S Wong YU Jun YANG Huanming 《Chinese Science Bulletin》 SCIE EI CAS 2003年第10期941-948,共8页
The genome sequence of the Severe Acute Respiratory Syndrome (SARS)-associated virus provides essential information for the identification of pathogen(s), exploration of etiology and evolution, interpretation of trans... The genome sequence of the Severe Acute Respiratory Syndrome (SARS)-associated virus provides essential information for the identification of pathogen(s), exploration of etiology and evolution, interpretation of transmission and pathogenesis, development of diagnostics, prevention by future vaccination, and treatment by developing new drugs. We report the complete genome sequence and comparative analysis of an isolate (BJ01) of the coronavirus that has been recognized as a pathogen for SARS. The genome is 29725 nt in size and has 11 ORFs (Open Reading Frames). It is composed of a stable region encoding an RNA-dependent RNA polymerase (composed of 2 ORFs) and a variable region representing 4 CDSs (coding sequences) for viral structural genes (the S, E, M, N proteins) and 5 PUPs (putative uncharacterized proteins). Its gene order is identical to that of other known coronaviruses. The sequence alignment with all known RNA viruses places this virus as a member in the family of Coronaviridae. Thirty putative substitutions have been identified by comparative analysis of the 5 SARS- associated virus genome sequences in GenBank. Fifteen of them lead to possible amino acid changes (non-synonymous mutations) in the proteins. Three amino acid changes, with predicted alteration of physical and chemical features, have been detected in the S protein that is postulated to beinvolved in the immunoreactions between the virus and its host. Two amino acid changes have been detected in the Mprotein, which could be related to viral envelope formation. Phylogenetic analysis suggests the possibility of non-human origin of the SARS-associated viruses but provides noevidence that they are man-made. Further efforts should focus on identifying the etiology of the SARS-associated virus and ruling out conclusively the existence of otherpossible SARS-related pathogen(s). 展开更多
关键词 比较分析 SARS 非典型肺炎 冠状病毒 病因学 发病机理 诊断学 疫苗
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全球环境变化对森林凋落物分解的影响 被引量:104
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作者 宋新章 江洪 +4 位作者 张慧玲 余树全 周国模 马元丹 Scott X. Chang 《生态学报》 CAS CSCD 北大核心 2008年第9期4414-4423,共10页
全球环境变化将对森林生态系统凋落物的分解和养分循环产生直接和间接的多重影响。就全球环境变化如全球变暖、大气CO2浓度升高、UV-B辐射增强、氮沉降等对凋落物分解影响的研究进展进行了综合述评。影响凋落物分解的内部因素为凋落物... 全球环境变化将对森林生态系统凋落物的分解和养分循环产生直接和间接的多重影响。就全球环境变化如全球变暖、大气CO2浓度升高、UV-B辐射增强、氮沉降等对凋落物分解影响的研究进展进行了综合述评。影响凋落物分解的内部因素为凋落物基质质量,外部因素包括生物因素(微生物和动物)和非生物因素(温度、水分和土壤性质等)。全球变暖对凋落物分解的非生物作用有正效应,也有负效应。全球变暖对凋落物化学组成虽然只有轻微的影响,但可以通过影响植被的物种组成来间接改变凋落物的产量、化学性质和分解。全球变暖对凋落物分解生物作用的主要影响是增强土壤微生物活性,从而加速凋落物的分解。CO2浓度上升将增加凋落物产量,并通过影响凋落物质量(提高C/N比、木质素/N比等)和生物环境(微生物的数量和活性)而影响分解过程。UV-B辐射和大气N沉降的增加亦对凋落物分解产生直接和间接的影响,但影响效果尚不很清楚,有待进一步的研究。总起来看,全球环境变化将通过影响凋落物的分解速率而对全球碳循环产生重要影响,但由于气候变化和凋落物分解响应的复杂性以及各因子之间的相互作用,气候变化对凋落物分解的总效应尚需更深入的研究来定量化。 展开更多
关键词 凋落物分解 全球变暖 大气CO2浓度升高 UV-B辐射 C循环
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Sodium butyrate attenuates high-fat diet-induced steatohepatitis in mice by improving gut microbiota and gastrointestinal barrier 被引量:93
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作者 Da Zhou Qin Pan +6 位作者 Feng-Zhi Xin Rui-Nan Zhang Chong-Xin He Guang-Yu Chen Chang Liu Yuan-Wen Chen Jian-Gao Fan 《World Journal of Gastroenterology》 SCIE CAS 2017年第1期60-75,共16页
AIM To investigate whether gut microbiota metabolite sodium butyrate (NaB) is an effective substance for attenuating non-alcoholic fatty liver disease (NAFLD) and the internal mechanisms. METHODS Male C57BL/6J mice we... AIM To investigate whether gut microbiota metabolite sodium butyrate (NaB) is an effective substance for attenuating non-alcoholic fatty liver disease (NAFLD) and the internal mechanisms. METHODS Male C57BL/6J mice were divided into three groups, normal control were fed standard chow and model group were fed a high-fat diet (HFD) for 16 wk, the intervention group were fed HFD for 16 wk and treated with NaB for 8 wk. Gut microbiota from each group were detected at baseline and at 16 wk, liver histology were evaluated and gastrointestinal barrier indicator such as zonula occluden-1 (ZO-1) were detected by immunohistochemistry and realtime-PCR, further serum or liver endotoxin were determined by ELISA and inflammation-or metabolism-associated genes were quantified by real-time PCR. RESULTS NaB corrected the HFD-induced gut microbiota imbalance in mice, while it considerably elevated the abundances of the beneficial bacteria Christensenellaceae, Blautia and Lactobacillus. These bacteria can produce butyric acid in what seems like a virtuous circle. And butyrate restored HFD induced intestinal mucosa damage, increased the expression of ZO-1 in small intestine, further decreased the levels of gut endotoxin in serum and liver compared with HF group. Endotoxin-associated genes such as TLR4 and Myd88, pro-inflammation genes such as MCP-1, TNF-alpha, IL-1, IL-2, IL-6 and IFN-gamma in liver or epididymal fat were obviously downregulated after NaB intervention. Liver inflammation and fat accumulation were ameliorated, the levels of TG and cholesterol in liver were decreased after NaB intervention, NAS score was significantly decreased, metabolic indices such as FBG and HOMA-IR and liver function indicators ALT and AST were improved compared with HF group. CONCLUSION NaB may restore the dysbiosis of gut microbiota to attenuate steatohepatitis, which is suggested to be a potential gut microbiota modulator and therapeutic substance for NAFLD. 展开更多
关键词 Non-alcoholic fatty liver disease Sodium butyrate Gut microbiota Gastrointestinal barrier ENDOTOXIN
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New eolian red clay sequence on the western Chinese Loess Plateau linked to onset of Asian desertification about 25 Ma ago 被引量:87
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作者 QIANG XiaoKe AN ZhiSheng +13 位作者 SONG YouGui CHANG Hong SUN YouBin LIU WeiGuo AO Hong DONG JiBao FU ChaoFeng WU Feng LU FengYan CAI YanJun ZHOU WeiJian CAO JunJi XU XinWen AI Li 《Science China Earth Sciences》 SCIE EI CAS 2011年第1期136-144,共9页
The expansion of inland Asia deserts has considerably influenced the environmental, social and economic activities in Asia. Aridification of inland Asia, especially timing of the initiation of Asian desertification, i... The expansion of inland Asia deserts has considerably influenced the environmental, social and economic activities in Asia. Aridification of inland Asia, especially timing of the initiation of Asian desertification, is a contentious topic in paleoclimatology. Late Cenozoic eolian loess-red clay sequences on the Chinese Loess Plateau, which possess abundant paleoclimatic and paleo-environmental information, can be regarded as an indicator of inland Asia desertification. Here we present a detailed magnetostratigraphic investigation of a new red clay sequence about 654 m in Zhuanglang located at the western Chinese Loess Plateau. Sedimentological, geochemical, mineralogical, and quartz morphological lines of evidence show that the red clay is of eolian origin. Magnetostratigraphic correlations indicate that this core sequence spans from 25.6 to 4.8 Ma, and typical eolian red clay appears as early as 25 Ma. This extends the lower limit of the red clay on the Chinese Loess Plateau from the previously thought early Miocene back into the late Oligocene. This new red clay record further implies that the inland Asia desertification was initiated at least by the late Oligocene. This sequence provides a unique high-resolution geological record for understanding the inland Asia desertification process since the late Oligocene. 展开更多
关键词 Chinese Loess Plateau eolian red clay MAGNETOSTRATIGRAPHY late Oiigocene inland Asia desertification
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帕博利珠单抗单用或与放疗联用治疗转移性非小细胞肺癌:两个随机试验的汇总分析 被引量:85
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作者 陈大卫(翻译) 于金明(校对) +18 位作者 Willemijn S M E Theelen Vivek Verma Brian P Hobbs Heike M U Peulen Joachim G J V Aerts Idris Bahce Anna Larissa N Niemeijer Joe Y Chang Patricia M de Groot Quynh-Nhu Nguyen Nathan I Comeaux George R Simon Ferdinandos Skoulidis Steven H Lin Kewen He Roshal Patel John Heymach Paul Baas James W Welsh 《中华肿瘤防治杂志》 CAS 北大核心 2021年第24期1841-1850,共10页
背景放疗可以提高整个机体对免疫治疗的应答。在Ⅱ期PEMBRO-RT研究和Ⅰ/Ⅱ期MDACC研究中,患有转移性非小细胞肺癌(NSCLC)的患者被随机分配入组,接受免疫治疗(帕博利珠单抗)+放疗联合疗法,或免疫治疗单一疗法。当上述2个研究单独分析时,... 背景放疗可以提高整个机体对免疫治疗的应答。在Ⅱ期PEMBRO-RT研究和Ⅰ/Ⅱ期MDACC研究中,患有转移性非小细胞肺癌(NSCLC)的患者被随机分配入组,接受免疫治疗(帕博利珠单抗)+放疗联合疗法,或免疫治疗单一疗法。当上述2个研究单独分析时,联合疗法组显示出潜在获益。由于每个研究的样本量较小,缓解率和结局并未显示出统计学意义,然而却有显著的临床获益。因此,本研究进行汇总分析,来判断放疗是否会改善转移性NSCLC患者的免疫治疗应答。方法PEMBRO-RT和MDACC研究纳入标准:患者年龄≥18岁,患有转移性NSCLC,且有≥1处未经放疗照射的病灶,以便进行射野外应答监测。PEMBRO-RT研究纳入曾接受过化疗患者,MDACC研究纳入曾接受过治疗或新诊断患者。2个研究中的患者均未接受过免疫治疗。在PEMBRO-RT研究中患者被等比例随机分配入组,并根据吸烟状态进行分层(分为<10年组和≥10年组)。MDACC研究的患者根据放疗计划可行性被等比例随机分配入2个受试组。由于联合治疗组的干预本质,每个研究中的放疗均不适用盲法。在2个研究中,不论是否进行放疗,均静脉滴入帕博利珠单抗(每3周200 mg)。在PEMBRO-RT研究中,在放疗(24 Gy 3次分割照射)结束后1周给予第1剂帕博利珠单抗。在MDACC研究中,在第1次放疗(50 Gy 4次分割照射或45 Gy 15次分割照射)同时给予帕博利珠单抗。仅检测未经照射病灶的应答。本研究的终点为最佳射野外(远隔)应答率(ARR)、最佳射野外疾病控制率(ACR)、12周时ARR、12周时ACR、无进展生存期(PFS)和总生存期(OS)。2个研究的意向治疗(ITT)人群均纳入分析。PEMBRO-RT研究(NCT02492568)和MDACC研究(NCT02444741)均在ClinicalTrials.gov上注册。发现纳入148例患者,76例接受帕博利珠单抗治疗,72例接受帕博利珠单抗+放疗治疗。所有患者随访时间中位数为33个月[四分位距(IQR):32.4~33.6]。148例� 展开更多
关键词 帕博利珠单抗 非小细胞肺癌 放疗 汇总分析
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Characterization of Hand,Foot,and Mouth Disease in China between 2008 and 2009 被引量:76
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作者 ZHANG Jing SUN JunLing CHANG ZhaoRui ZHANG WeiDong WANG ZiJun FENG ZiJian 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2011年第3期214-221,共8页
Objective To investigate the epidemiological and cl (HFMD) since several outbreaks of HFMD caused between 2007 and 2008. inical features of hand, foot and mouth disease by enteroviruses were documented in China Meth... Objective To investigate the epidemiological and cl (HFMD) since several outbreaks of HFMD caused between 2007 and 2008. inical features of hand, foot and mouth disease by enteroviruses were documented in China Methods HFMD cases reported to the National Infectious Disease Information Management System database between May 2008 and April 2009 were assessed. Clinical features in some of the severe and fatal cases were analyzed the etiology of the outbreaks was investigated. Results 89.1% of reported HFMD cases were found in children〈5 year-old with an age-specific incidence rate of 834.1/100 000 in the first year as the notifiable disease in China from May 2008 to April 2009. The incidence, mortality and percentage of severe cases were studied for three regions of China and found to be highest in the central region. The incidence of severe cases and mortality in rural population were significantly higher than those in urban population. Among the laboratory confirmed EV17 positive cases there were 52.6% mild, 83.5% severe, and 96.1% fatal cases. More myoclonic jerks were found in the severe case group than in group that died. Tachypnea, lip purpling, pink foaming and low limb temperature occurred more frequently in the fatal cases than in the severe cases. Conclusion The epidemic of HFMD in China was characterized predominantly by EV71 infections, had relatively high mortality rates especially in the central region, and was most prevalent in young, rural populations. 展开更多
关键词 Hand foot and mouth disease ENTEROVIRUS EPIDEMIOLOGY Clinical features
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肛裂临床诊治指南(第三次修订) 被引量:71
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作者 Farshid Araghizadeh ~ Robin Boushey +30 位作者 Sridhar Chalasani George Chang Robert Cima Gary Dunn Daniel Feingold Philip Fleshner Daniel Geisler Jill Genua Sharon Gregorcyk Daniel Herzig Andreas Kaiser Ravin Kumar David Larson Steven Mills John Monson P. Terry Phang Feza Remzi David Rivadeneira Howard Ross Peter Senatore Elin Sigurdson Thomas Stahl Scott Steele Scott Strong Charles Tement Judith Trudel Madhulika Varnna Martin Weiser 丁义江(译) 皇甫少华(译) 丁曙晴(译) 《中华胃肠外科杂志》 CAS CSCD 2013年第7期689-690,共2页
“美国结直肠外科医师协会(American Societyof ColonandRectal Surgeons.ASCRS)”(协会)致力于推进结直肠和肛门疾病的相关理论以及预防和诊疗水平的提高,给患者提供优质的医疗服务。“标准委员会”由协会中在结直肠外科方面有... “美国结直肠外科医师协会(American Societyof ColonandRectal Surgeons.ASCRS)”(协会)致力于推进结直肠和肛门疾病的相关理论以及预防和诊疗水平的提高,给患者提供优质的医疗服务。“标准委员会”由协会中在结直肠外科方面有显著专长的成员组成。该委员会的建立是为了引领国际结直肠和肛门疾病诊治的发展,以建立具有循证医学证据的临床诊疗指南。指南是涵盖性的,非指令性的,目的是为临床决策提供信息,而非具体的治疗方法。指南适用于所有相关的医护人员以及希望得到相应指南中疾病的相关诊治信息的患者。 展开更多
关键词 诊治指南 临床决策 结直肠外科 修订 肛裂 医师协会 肛门疾病 循证医学证据
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三维复杂地形近地表速度估算及地震层析静校正 被引量:60
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作者 刘伊克 CHANG Xu +2 位作者 常旭 王辉 李福中 《地球物理学报》 SCIE EI CAS CSCD 北大核心 2001年第2期272-278,共7页
在地表一致性模型的基础上提出一种可适用于宽线剖面、弯曲测线、传统的二维和目前广泛使用的三维地震观测 .在地形及近地表低降速带地质结构复杂的探区 ,低降速带厚度及速度估算的精度是静校正处理的关键 .本研究根据三维地震观测的初... 在地表一致性模型的基础上提出一种可适用于宽线剖面、弯曲测线、传统的二维和目前广泛使用的三维地震观测 .在地形及近地表低降速带地质结构复杂的探区 ,低降速带厚度及速度估算的精度是静校正处理的关键 .本研究根据三维地震观测的初至走时数据 ,利用最小平方与QR分解相结合的算法 ,在三维空间重建近地表低降速带速度模型 ,根据重建速度模型实现了静校正长波长分量与短波长分量的同步计算 .分析了复杂的近地表低降速带模型初至波的性质 ,在观测值的自动拾取以及理论值的计算中充分考虑了可能成为初至波的直达波、折射波和反射波的利用 ,提高了低降速带速度模型反演的精度 .在初至走时观测数据的拾取中 ,本研究采用分形算法克服了初至波波形差异以及折射波相位反转导致的拾取误差 ,实现了三维初至拾取的大规模全自动化运算 .在射线路径与初至波理论走时的计算中 ,本研究采用一种计算量与模型复杂程度无关的三维射线追踪方法 ,该方法以最小走时射线路径保证了与观测数据有同等意义的初至波的射线追踪及理论走时的计算 .野外实际资料的处理结果表明了方法的有效性 . 展开更多
关键词 近地表速度模型 层析静校正 走时拾取 三维射线追踪 LSQR算法 地震勘探 数字处理
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基于差分雷达干涉测量的矿区地面沉降监测研究 被引量:52
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作者 董玉森 Ge Linlin +1 位作者 Chang Hsingchun 张志 《武汉大学学报(信息科学版)》 EI CSCD 北大核心 2007年第10期888-891,共4页
收集了1992年12月至1998年6月JERS-1L波段雷达数据,利用差分雷达干涉测量技术进行地面沉降监测研究。通过"二轨法"进行差分处理,选择其中的6景差分雷达干涉图进行分析。在研究区内发现了4个沉降区域,并按照时间序列通过对地... 收集了1992年12月至1998年6月JERS-1L波段雷达数据,利用差分雷达干涉测量技术进行地面沉降监测研究。通过"二轨法"进行差分处理,选择其中的6景差分雷达干涉图进行分析。在研究区内发现了4个沉降区域,并按照时间序列通过对地面形变图进行分析,获取其中两个沉降区最大的垂直沉降量。 展开更多
关键词 地面沉降 雷达差分干涉测量 JERS-1卫星
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Solid-pseudopapillary tumor of the pancreas: Clinical experience and literature review 被引量:59
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作者 Hsueh-Lien Huang Shou-Chuan Shih +3 位作者 Wen-Hsiung Chang Tsang-En Wang Ming-Jen Chen Yu-Jan Chan 《World Journal of Gastroenterology》 SCIE CAS CSCD 2005年第9期1403-1409,共7页
AIM: To evaluate the clinical presentations of solidpseudopapillary tumor of the pancreas (SPT) and examine the diagnosis, treatment, low grade malignant potential of this rare disease.METHODS: We retrospectively revi... AIM: To evaluate the clinical presentations of solidpseudopapillary tumor of the pancreas (SPT) and examine the diagnosis, treatment, low grade malignant potential of this rare disease.METHODS: We retrospectively reviewed a series of seven patients with SPT managed in our hospital between July 1990 and October 2003. Six females and one male with mean age of 31 years (range 13 to 50 years) were diagnosed with SPT at our institution.RESULTS: Clinical presentation included a palpable abdominal mass in two patients and vague abdominal discomfort in another two. Two patients were asymptomatic;their tumors were found incidentally on abdominal sonographic examination for other reasons. The final patient was admitted with hemoperitoneum secondary to tumor rupture. The mean diameter of the tumors in the seven patients was 10.5 cm (range 5 to 20 cm). The lesions were located in the body and tail in five cases and in the head of the pancreas in two. Surgical procedures included distal pancreatectomy (3), distal pancreatectomy with splenectomy (2), pancreaticoduodenectomy (1) and a pylorus-preserving Whipple procedure (1). There were gross adhesions or histological evidence of infiltration to the adjacent pancreas and/or splenic capsule in four cases. None of the patients received adjuvant therapy.The mean follow up was 7 years (range 0.5 to 14 years).One patient developed multiple liver metastases after 14 years of follow up.CONCLUSION: SPT is a rare tumor that behaves less aggressively than other pancreatic tumor. However, in cases with local invasion, long-term follow up is advisable. 展开更多
关键词 Solid-pseudopapillary tumor of the pancreas Distal pancreatectomy PANCREATICODUODENECTOMY
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Mobius Isoparametric Hypersurfaces in S^(n+1) with Two Distinct Principal Curvatures 被引量:55
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作者 Hai Zhong LI Department of Mathematics, Tsinghua University. Beijing 100084. P. R. China Hui Li LIU Department of Mathematics, Northeastern University. Shenyang 110000. P. R. China Chang Ping WANG Key Laboratory of Pure and Applied Mathematics, School of Mathematical Sciences. Peking University, Beijing 100871, P. R. China Guo Song ZHAO Department of Mathematics, Sichuan University, Chengdu 610064. P. R. China 《Acta Mathematica Sinica,English Series》 SCIE CSCD 2002年第3期437-446,共10页
A hypersurface x: M→S^(n+1) without umbilic point is called a Mbius isoparametric hypersurface if its Mbius form Φ=-ρ^(-2)∑_i(ei(H)+∑_j(h_(ij)-Hδ_(ij))e_j(logρ))θ_i vanishes and its Mbius shape operator S=ρ^(... A hypersurface x: M→S^(n+1) without umbilic point is called a Mbius isoparametric hypersurface if its Mbius form Φ=-ρ^(-2)∑_i(ei(H)+∑_j(h_(ij)-Hδ_(ij))e_j(logρ))θ_i vanishes and its Mbius shape operator S=ρ^(-1)(S-Hid) has constant eigenvalues. Here {e_i} is a local orthonormal basis for I=dx·dx with dual basis {θ_i}, II=∑_(ij)h_(ij)θ_iθ_J is the second fundamental form, H=1/n∑_i h_(ij), ρ~2=n/(n-1)(‖II‖~2-nH^2) and S is the shape operator of x. It is clear that any conformal image of a (Euclidean) isoparametric hypersurface in S^(n+1) is a Mbius isoparametric hypersurface, but the converse is not true. In this paper we classify all Mbius isoparametric hypersurfaces in S^(n+1) with two distinct principal curvatures up to Mbius transformations. By using a theorem of Thorbergsson [1] we also show that the number of distinct principal curvatures of a compact Mbius isoparametric hypersurface embedded in S^(n+1) can take only the values 2, 3, 4, 6. 展开更多
关键词 Mobius geometry Isoparametric hypersurface Principal curvature
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Evaluation of the effect of partial splenic embolization on platelet values for liver cirrhosis patients with thrombocytopenia 被引量:56
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作者 Chi-Ming Lee Ting-Kai Leung +5 位作者 Hung-Jung Wang Wei-Hsing Lee Li-Kuo Shen Jean-Dean Liu Chun-Chao Chang Ya-Yen Chen 《World Journal of Gastroenterology》 SCIE CAS CSCD 2007年第4期619-622,共4页
AIM: TO investigate the effect of partial splenic embolization (PSE) on platelet values in liver cirrhosis patients with thrombocytopenia and to determine the effective embolization area for platelet values improve... AIM: TO investigate the effect of partial splenic embolization (PSE) on platelet values in liver cirrhosis patients with thrombocytopenia and to determine the effective embolization area for platelet values improvement.METHODS: Blood parameters and liver function indicators were measured on 10 liver cirrhosis patients (6 in Child-Pugh grade A and 4 in grade B) with thrombocytopenia (platelet values 〈 80 × 10^3/μL) before embolization. Computed tomography scan was also needed in advance to acquire the splenic baseline. After 2 to 3 d, angiography and splenic embolization were performed. A second computed tomography scan was made to confirm the embolization area after 2 to 3 wk of embolization. The blood parameters of patients were also examined biweekly during the 1 year follow-up period. RESULTS: According to the computed tomography images after partial splenic embolization, we divided all paUents into two groups: low (〈 30%), and high (≥ 30%) embolization area groups. The platelet values were increased by 3 times compared to baseline levels after 2 wk of embolization in high embolization area group. In addition, there were significant differences in platelet values between low and high embolization area groups. GPT values decreased significantly in all patients after 2 wk of embolization. The improvement in platelet and GPT values still persisted until 1 year after PSE. In addition, 3 of 4 (75%) Child-Pugh grade B patients progressed to grade A after 2 mo of PSE. The complication rate in 〈 30% and ≥30% embolization area groups was 50% and 100%, respectively. CONCLUSION: Partial splenic embolization is an effective method to improve platelet values and GPT values in liver cirrhosis patients with thrombocytopenia and the ≥ 30% embolization area is meaningful for platelet values improvement. The relationship between the complication rate and embolization area needs further studies. 展开更多
关键词 Partial splenic embolization Liver cirrhosis THROMBOCYTOPENIA
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Factors predicting occurrence and prognosis of hepatitis-B-virus-related hepatocellular carcinoma 被引量:56
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作者 Yi-Fang Han Jun Zhao +4 位作者 Li-Ye Ma Jian-Hua Yin Wen-Jun Chang Hong-Wei Zhang Guang-Wen Cao 《World Journal of Gastroenterology》 SCIE CAS CSCD 2011年第38期4258-4270,共13页
Primary liver cancer is an important cause of cancer death, and hepatocellular carcinoma (HCC) accounts for 70%-85% of total liver cancer worldwide. Chronic hepatitis B virus (HBV) infection contributes to 〉 75% ... Primary liver cancer is an important cause of cancer death, and hepatocellular carcinoma (HCC) accounts for 70%-85% of total liver cancer worldwide. Chronic hepatitis B virus (HBV) infection contributes to 〉 75% of HCC cases. High serum viral load is the most reliable indicator of viral replication in predicting development of HCC. HBV genotype C is closely associated with HCC in cirrhotic patients aged 〉 50 years, whereas genotype B is associated with development of HCC in non-cirrhotic young patients and postoperative relapse of HCC. Different HBV subgenotypes have distinct patterns of mutations, which are clearly associated with increased risk of HCC. Mutations accumulate during chronic HBV infection and predict occurrence of HCC. Chronic inflammation leads to increased frequency of viral mutation via cellular cytidine deaminase induction. Mutations are negatively selected by host immunity, whereas some immuno-escaped HBV mutants are active in hepatocarcinogenesis. Inflammatory pathways contribute to the inflammation-necrosis-regeneration process, ultimately HCC. Their hallmark molecules can predict malignancy in HBV-infected subjects. Continuing inflammation is involved in hepatocarcinogenesis and closely related to recurrence and metastasis. HBV load, genotype C, viral mutations and expression of inflammatory molecules in HBV-related HCC tissues are significantly associated with poor prognosis. Imbalance between intratumoral CD8^+T cells and regulatory T cells or Thl and Th2 cytokines in peritumoral tissues can predict prognosis of HBV-related HCC. These factors are important for developing active prevention and surveillance of HBV-infected subjects who are more likely to develop HCC, or for tailoring suitable treatment to improve survival or postpone postoperative recurrence of HCC. 展开更多
关键词 Hepatitis B virus Hepatocellular carcinoma Viral load GENOTYPE Mutation Immune cells Signal-ing pathway CYTOKINE PROGNOSIS
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A novel heterodimeric cytokine consisting of IL-17 and IL-17F regulates inflammatory responses 被引量:48
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作者 Seon Hee Chang 《Cell Research》 SCIE CAS CSCD 2007年第5期435-440,共6页
CD4+ helper T (TH) cells play crucial roles in immune responses. Recently a novel subset of TH cells, termed THIL-17, TH 17 or inflammatory TH (THi), has been identified as critical mediators of tissue inflammati... CD4+ helper T (TH) cells play crucial roles in immune responses. Recently a novel subset of TH cells, termed THIL-17, TH 17 or inflammatory TH (THi), has been identified as critical mediators of tissue inflammation. These cells produce IL-17 (also called IL-17A) and IL-17F, two most homologous cytokines sharing similar regulations. Here we report that when overexpressed in 293T cells, IL-17 and IL-17F form not only homodimers but also heterodimers, which we name as IL-17A/F. Fully differentiated mouse THi cells also naturally secrete IL-17A/F as well as IL-17 and IL-17F homodimeric cytokines. Recombinant IL-17A/F protein exhibits intermediate levels of potency in inducing IL-6 and KC (CXCL 1) as compared to homodimeric cytokines. IL-17A/F regulation of IL-6 and KC expression is dependent on IL-17RA and TRAF6. Thus, IL-17A/F cytokine represents another mechanism whereby T cells regulate inflammatory responses and may serve as a novel target for treating various immune-mediated diseases. 展开更多
关键词 INFLAMMATION IL- 17 T cells
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Mesozoic subduction-accretion zone in northeastern South China Sea inferred from geophysical interpretations 被引量:53
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作者 ZHOU Di1, WANG Wanyin2, WANG Jialin3, PANG Xiong4, CAI Dongsheng5 & SUN Zhen1 1. Key Laboratory of Marginal Sea Geology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guang- zhou 510301, China 2. College of Geological and Topographical Engineering, Chang’an University, Xi’an 710054, China +2 位作者 3. Key Laboratory of Marine Geology, Tongji University, Shanghai 200092, China 4. China National Offshore Oil Co. Limited – Shenzhen Branch, Shenzhen 518067, China 5. China National Offshore Oil Co. Limited – Research Center, Beijing 100027, China 《Science China Earth Sciences》 SCIE EI CAS 2006年第5期471-482,共12页
A segment of Mesozoic subduction-accretion zone was inferred across thenortheastern South China Sea at approximately NE450 orientation. Basic evidence includes thefollowing: A belt of peek gross horizontal Bouguer gra... A segment of Mesozoic subduction-accretion zone was inferred across thenortheastern South China Sea at approximately NE450 orientation. Basic evidence includes thefollowing: A belt of peek gross horizontal Bouguer gravity gradient (PGHGBA) is comparable in sizeand intensity to that of the Manila subduction-accretion zone. A belt of high positive magneticanomalies appears to the north and sub-parallel to the PGHGBA, representing the volcanic arcassociated to the subduction zone. The PGHGBA crosses obliquely both Cenozoic structures and presentseafloor topography, indicating a pre-Cenozoic age. The segment is offset left-laterally byNW-running strike-slip faults, in concord with the Mesozoic stress field of South China. Inaddition, the existence of the subduction zone is supported by wide-angle seismic data obtained indifferent years by different institutions. At approximate localities, a north-dipping ramp of Mohosurface is indicated by records of ocean-bottom seismometers, and a strong reflector about 8 kmbeneath the Moho reflector is indicated by both OBS and long-cable seismic records. Theidentification of a segment of Mesozoic subduction zone in NE South China Sea fills nicely the gapof the Great Late Mesozoic Circum SE Asia Subduction-acrretion Zone, which extended from Sumatra,Java, SE Kalimantan to N Palawan, and from Taiwan, Ryukyu to SW Japan. 展开更多
关键词 Mesozoic SUBDUCTION zone SE Asia NE SOUTH China Sea geophysics.
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Petawatt and exawatt class lasers worldwide 被引量:52
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作者 Colin N.Danson Constantin Haefner +30 位作者 Jake Bromage Thomas Butcher Jean-Christophe FChanteloup Enam A.Chowdhury Almantas Galvanauskas Leonida A.Gizzi Joachim Hein David I.Hillier Nicholas W.Hopps Yoshiaki Kato Efim A.Khazanov Ryosuke Kodama Georg Korn Ruxin Li Yutong Li Jens Limpert Jingui Ma Chang Hee Nam David Neely Dimitrios Papadopoulos Rory R.Penman Liejia Qian Jorge J.Rocca andrey A.Shaykin Craig W.Siders Christopher Spindloe Sándor Szatmári Raoul M.G.M.Trines Jianqiang Zhu Ping Zhu Jonathan D.Zuegel 《High Power Laser Science and Engineering》 SCIE CAS CSCD 2019年第3期168-221,共54页
In the 2015 review paper‘Petawatt Class Lasers Worldwide’a comprehensive overview of the current status of highpower facilities of>200 TW was presented.This was largely based on facility specifications,with some ... In the 2015 review paper‘Petawatt Class Lasers Worldwide’a comprehensive overview of the current status of highpower facilities of>200 TW was presented.This was largely based on facility specifications,with some description of their uses,for instance in fundamental ultra-high-intensity interactions,secondary source generation,and inertial confinement fusion(ICF).With the 2018 Nobel Prize in Physics being awarded to Professors Donna Strickland and Gerard Mourou for the development of the technique of chirped pulse amplification(CPA),which made these lasers possible,we celebrate by providing a comprehensive update of the current status of ultra-high-power lasers and demonstrate how the technology has developed.We are now in the era of multi-petawatt facilities coming online,with 100 PW lasers being proposed and even under construction.In addition to this there is a pull towards development of industrial and multi-disciplinary applications,which demands much higher repetition rates,delivering high-average powers with higher efficiencies and the use of alternative wavelengths:mid-IR facilities.So apart from a comprehensive update of the current global status,we want to look at what technologies are to be deployed to get to these new regimes,and some of the critical issues facing their development. 展开更多
关键词 exawatt LASERS HIGH-POWER LASERS PETAWATT LASERS ultra-high INTENSITY
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Terrestrial carbon sinks in China and around the world and their contribution to carbon neutrality 被引量:52
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作者 Yuanhe Yang Yue Shi +25 位作者 Wenjuan Sun Jinfeng Chang Jianxiao Zhu Leiyi Chen Xin Wang Yanpei Guo Hongtu Zhang Lingfei Yu Shuqing Zhao Kang Xu Jiangling Zhu Haihua Shen Yuanyuan Wang Yunfeng Peng Xia Zhao Xiangping Wang Huifeng Hu Shiping Chen Mei Huang Xuefa Wen Shaopeng Wang Biao Zhu Shuli Niu Zhiyao Tang Lingli Liu Jingyun Fang 《Science China(Life Sciences)》 SCIE CAS CSCD 2022年第5期861-895,共35页
Enhancing the terrestrial ecosystem carbon sink(referred to as terrestrial C sink) is an important way to slow down the continuous increase in atmospheric carbon dioxide(CO_(2)) concentration and to achieve carbon neu... Enhancing the terrestrial ecosystem carbon sink(referred to as terrestrial C sink) is an important way to slow down the continuous increase in atmospheric carbon dioxide(CO_(2)) concentration and to achieve carbon neutrality target.To better understand the characteristics of terrestrial C sinks and their contribution to carbon neutrality,this review summarizes major progress in terrestrial C budget researches during the past decades,clarifies spatial patterns and drivers of terrestrial C sources and sinks in China and around the world,and examines the role of terrestrial C sinks in achieving carbon neutrality target.According to recent studies,the global terrestrial C sink has been increasing from a source of (-0.2±0.9) Pg C yr^(-1)(1 Pg=1015g)in the 1960s to a sink of (1.9±1.1) Pg C yr^(-1) in the 2010s.By synthesizing the published data,we estimate terrestrial C sink of 0.20–0.25 Pg C yr^(-1) in China during the past decades,and predict it to be 0.15–0.52 Pg C yr^(-1) by 2060.The terrestrial C sinks are mainly located in the mid-and high latitudes of the Northern Hemisphere,while tropical regions act as a weak C sink or source.The C balance differs much among ecosystem types:forest is the major C sink;shrubland,wetland and farmland soil act as C sinks;and whether the grassland functions as C sink or source remains unclear.Desert might be a C sink,but the magnitude and the associated mechanisms are still controversial.Elevated atmospheric CO_(2) concentration,nitrogen deposition,climate change,and land cover change are the main drivers of terrestrial C sinks,while other factors such as fires and aerosols would also affect ecosystem C balance.The driving factors of terrestrial C sink differ among regions.Elevated CO_(2) concentration and climate change are major drivers of the C sinks in North America and Europe,while afforestation and ecological restoration are additionally important forcing factors of terrestrial C sinks in China.For future studies,we recommend the necessity for intensive and long-term ec 展开更多
关键词 terrestrial ecosystem carbon sink carbon neutrality carbon cycle global warming
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Deferoxamine promotes recovery of traumatic spinal cord injury by inhibiting ferroptosis 被引量:52
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作者 Xue Yao Yan Zhang +12 位作者 Jian Hao Hui-Quan Duan Chen-Xi Zhao Chao Sun Bo Li Bao-You Fan Xu Wang Wen-Xiang Li Xuan-Hao Fu Yong Hu Chang Liu Xiao-Hong Kong Shi-Qing Feng 《Neural Regeneration Research》 SCIE CAS CSCD 2019年第3期532-541,共10页
Ferroptosis is an iron-dependent novel cell death pathway. Deferoxamine, a ferroptosis inhibitor, has been reported to promote spinal cord injury repair. It has yet to be clarified whether ferroptosis inhibition repre... Ferroptosis is an iron-dependent novel cell death pathway. Deferoxamine, a ferroptosis inhibitor, has been reported to promote spinal cord injury repair. It has yet to be clarified whether ferroptosis inhibition represents the mechanism of action of Deferoxamine on spinal cord injury recovery. A rat model of Deferoxamine at thoracic 10 segment was established using a modified Allen's method. Ninety 8-week-old female Wistar rats were used. Rats in the Deferoxamine group were intraperitoneally injected with 100 mg/kg Deferoxamine 30 minutes before injury. Simultaneously, the Sham and Deferoxamine groups served as controls. Drug administration was conducted for 7 consecutive days. The results were as follows:(1) Electron microscopy revealed shrunken mitochondria in the spinal cord injury group.(2) The Basso, Beattie and Bresnahan locomotor rating score showed that recovery of the hindlimb was remarkably better in the Deferoxamine group than in the spinal cord injury group.(3) The iron concentration was lower in the Deferoxamine group than in the spinal cord injury group after injury.(4) Western blot assay revealed that, compared with the spinal cord injury group, GPX4, xCT, and glutathione expression was markedly increased in the Deferoxamine group.(5) Real-time polymerase chain reaction revealed that, compared with the Deferoxamine group, mRNA levels of ferroptosis-related genes Acyl-CoA synthetase family member 2(ACSF2) and iron-responsive element-binding protein 2(IREB2) were up-regulated in the Deferoxamine group.(6) Deferoxamine increased survival of neurons and inhibited gliosis. These findings confirm that Deferoxamine can repair spinal cord injury by inhibiting ferroptosis. Targeting ferroptosis is therefore a promising therapeutic approach for spinal cord injury. 展开更多
关键词 nerve REGENERATION iron spinal CORD INJURY secondary INJURY ferroptosis DEFEROXAMINE GPX4 xCT treatment ASTROGLIOSIS lipid PEROXIDATION neural REGENERATION
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Astragalus polysaccharide enhances immunity and inhibits H9N2 avian influenza virus in vitro and in vivo 被引量:50
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作者 Sanpha Kallon Xiaorong Li +7 位作者 Jun Ji Cuiying Chen Qianyun Xi Shuang Chang Chunyi Xue Jingyun Ma Qingmei Xie Youngliang Zhang 《Journal of Animal Science and Biotechnology》 SCIE CAS 2013年第4期325-335,共11页
This study investigated the humoral immunization of Astragalus polysaccharide (APS) against HgN2 avian influenza virus (H9N2 AIV) infection in chickens. The effects of APS treatment on H9N2 infection was evaluated... This study investigated the humoral immunization of Astragalus polysaccharide (APS) against HgN2 avian influenza virus (H9N2 AIV) infection in chickens. The effects of APS treatment on H9N2 infection was evaluated by an Mqq- [3(4, 5-dimethylthiazol-2-yl)-2, 3-diphenyl tetrazolium bromide] assay and analysis of MFIC and cytokine mRNA expression. The effect on lymphocyte and serum antibody titers in vivo was also investigated. IL-4, IL-6, IL-10, LITAF, IL-12 and antibody titers to H9N2 AIV wet enhanced in the first week after APS treatment. The results indicated that APS treatment reduces H9N2 AIV replication and promotes early humoral immune responses in young chickens.This study investigated the humoral immunization of Astragalus polysaccharide (APS) against HgN2 avian influenza virus (H9N2 AIV) infection in chickens. The effects of APS treatment on HgN2 infection was evaluated by an M]q- [3(4, 5-dimethylthiazol-2-yl)-2, 3-diphenyl tetrazolium bromide] assay and analysis of MHC and cytokine mRNA expression. The effect on lymphocyte and serum antibody titers in vivo was also investigated. IL-4, IL-6, IL-10, LITAF, IL-12 and antibody titers to PIgN2 AIV were enhanced in the first week after APS treatment. The results indicated that APS treatment reduces HgN2 AIV replication and promotes early humoral immune responses in young chickens. 展开更多
关键词 Astrogalus polysaccharide HgN2 avian influenza virus Immune effect
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