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Future Physics Programme of BESⅢ 被引量:538
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作者 M.Ablikim M.N.Achasov +147 位作者 P.Adlarson S.Ahmed M.Albrecht M.Alekseev A.Amoroso F.F.An Q.An Y.Bai O.Bakina R.Baldini Ferroli Y.Ban K.Begzsuren J.V.Bennett N.Berger M.Bertani D.Bettoni F.Bianchi J Biernat J.Bloms I.Boyko R.A.Briere L.Calibbi H.Cai X.Cai A.Calcaterra G.F.Cao N.Cao S.A.Cetin J.Chai J.F.Chang W.L.Chang J.Charles G.Chelkov Chen G.Chen H.S.Chen J.C.Chen M.L.Chen S.J.Chen Y.B.Chen H.Y.Cheng W.Cheng G.Cibinetto F.Cossio X.F.Cui H.L.Dai J.P.Dai X.C.Dai A.Dbeyssi D.Dedovich Z.Y.Deng A.Denig Denysenko M.Destefanis S.Descotes-Genon F.De Mori Y.Ding C.Dong J.Dong L.Y.Dong M.Y.Dong Z.L.Dou S.X.Du S.I.Eidelman J.Z.Fan J.Fang S.S.Fang Y.Fang R.Farinelli L.Fava F.Feldbauer G.Felici C.Q.Feng M.Fritsch C.D.Fu Y.Fu Q.Gao X.L.Gao Y.Gao Y.Gao Y.G.Gao Z.Gao B.Garillon I.Garzia E.M.Gersabeck A.Gilman K.Goetzen L.Gong W.X.Gong W.Gradl M.Greco L.M.Gu M.H.Gu Y.T.Gu A.Q.Guo F.K.Guo L.B.Guo R.P.Guo Y.P.Guo A.Guskov S.Han X.Q.Hao F.A.Harris K.L.He F.H.Heinsius T.Held Y.K.Heng Y.R.Hou Z.L.Hou H.M.Hu J.F.Hu T.Hu Y.Hu G.S.Huang J.S.Huang X.T.Huang X.Z.Huang Z.L.Huang N.Huesken T.Hussain W.Ikegami Andersson W.Imoehl M.Irshad Q.Ji Q.P.Ji X.B.Ji X.L.Ji H.L.Jiang X.S.Jiang X.Y.Jiang J.B.Jiao Z.Jiao D.P.Jin S.Jin Y.Jin T.Johansson N.Kalantar-Nayestanaki X.S.Kang R.Kappert M.Kavatsyuk B.C.Ke I.K.Keshk T.Khan A.Khoukaz P.Kiese R.Kiuchi R.Kliemt L. 《Chinese Physics C》 SCIE CAS CSCD 2020年第4期I0001-I0004,1-102,共106页
There has recently been a dramatic renewal of interest in hadron spectroscopy and charm physics. This renaissance has been driven in part by the discovery of a plethora of charmonium-like XYZ states at BESⅢ and B fac... There has recently been a dramatic renewal of interest in hadron spectroscopy and charm physics. This renaissance has been driven in part by the discovery of a plethora of charmonium-like XYZ states at BESⅢ and B factories, and the observation of an intriguing proton-antiproton threshold enhancement and the possibly related X(1835) meson state at BESⅢ, as well as the threshold measurements of charm mesons and charm baryons. We present a detailed survey of the important topics in tau-charm physics and hadron physics that can be further explored at BESⅢ during the remaining operation period of BEPCⅡ. This survey will help in the optimization of the data-taking plan over the coming years, and provides physics motivation for the possible upgrade of BEPCⅡ to higher luminosity. 展开更多
关键词 MESON HADRON optimization
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数字孪生标准体系 被引量:157
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作者 陶飞 马昕 +25 位作者 胡天亮 黄祖广 程江峰 戚庆林 张萌 刘蔚然 张贺 王尚刚 薛瑞娟 黎晓东 韦莎 刘默 刘棣斐 周剑 张健 李勤 欧阳劲松 胡雯 葛军 闫丽娟 贺东东 陈录城 徐慧 刘魁 易旺民 陈虎 《计算机集成制造系统》 EI CSCD 北大核心 2019年第10期2405-2418,共14页
数字孪生(Digital Twin)作为实现数字化、智能化、服务化等先进理念的重要使能技术,当前备受学术界和工业界关注,如何在各领域落地应用更是关注的重点。但在数字孪生理论研究与落地应用过程中,发现缺乏数字孪生相关术语、系统架构、适... 数字孪生(Digital Twin)作为实现数字化、智能化、服务化等先进理念的重要使能技术,当前备受学术界和工业界关注,如何在各领域落地应用更是关注的重点。但在数字孪生理论研究与落地应用过程中,发现缺乏数字孪生相关术语、系统架构、适用准则等标准的参考,导致不同用户对数字孪生的理解与认识存在差异;缺乏数字孪生相关模型、数据、连接与集成、服务等标准的参考,导致模型间、数据间、模型与数据间集成难、一致性差等问题,造成新的孤岛;缺乏相关适用准则、实施要求、工具和平台等标准的参考,造成用户或企业不知如何使用数字孪生。为解决上述问题,亟需数字孪生相关标准来参考和指导。因此,首先从数字孪生概念的理解与沟通、关键技术研究与实施、行业落地应用3个角度对数字孪生标准的需求进行了分析。在此基础上,结合前期提出的数字孪生五维模型,与国内本领域相关标准技术委员会及应用企业(包括机床、卫星、发动机、工程机械装备等行业)共同建立了一套数字孪生标准体系架构。该标准体系主要由数字孪生基础共性标准、关键技术标准、工具/平台标准、测评标准、安全标准、行业应用标准6部分构成,期望相关工作能为数字孪生标准研究与制定人员提供参考,同时为数字孪生落地应用提供指导。 展开更多
关键词 数字孪生 标准体系 数字孪生五维模型 基础共性 关键技术 工具/平台 行业应用
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碳酸盐黏土型锂资源的发现及意义 被引量:103
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作者 温汉捷 罗重光 +6 位作者 杜胜江 于文修 顾汉念 凌坤跃 崔燚 李阳 杨季华 《科学通报》 EI CAS CSCD 北大核心 2020年第1期53-59,共7页
黏土型锂资源具有矿床规模大、分布稳定、开发利用成本低的特点,成为近年来全球寻找新类型锂资源的一个重要方向.已报道的黏土型锂矿床成因上均与火山物质联系密切,本研究提出了成因机制与碳酸盐岩风化-沉积有关"碳酸盐黏土型锂矿... 黏土型锂资源具有矿床规模大、分布稳定、开发利用成本低的特点,成为近年来全球寻找新类型锂资源的一个重要方向.已报道的黏土型锂矿床成因上均与火山物质联系密切,本研究提出了成因机制与碳酸盐岩风化-沉积有关"碳酸盐黏土型锂矿床"的成矿新类型.主要地质地球化学特征可归纳为:(1)成矿物质来自基底的不纯碳酸盐岩;(2)主要以吸附方式存在于蒙脱石相中;(3)沉积环境对锂的富集具有重要的控制作用,还原、低能、滞留、局限的古地理环境有利于Li富集;(4)除Li外,还可能有Ga和REE的富集.根据这一新的成矿模型,通过科研示范性勘查,在滇中地区获得34×10~4t氧化锂资源量,达到超大型规模,验证了"碳酸盐黏土型锂矿床"这一新类型资源的成矿潜力.由于我国具有这一有利成矿条件的地区众多,可以预期,碳酸盐黏土型锂资源将有望成为我国新的重要的锂资源来源. 展开更多
关键词 碳酸盐岩 黏土型 风化作用
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语文学习任务究竟是什么? 被引量:79
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作者 文艺 崔允漷 《课程.教材.教法》 CSSCI 北大核心 2022年第2期12-19,共8页
语文学习任务是新一轮修订的语文课程标准的关键概念,其内涵是否清晰,事关语文课程改革的深入推进。语文学习任务在《普通高中语文课程标准(2017年版2020年修订)》中使用了147次,但没有明确的界定,导致语文学习任务在后续的讨论和教学... 语文学习任务是新一轮修订的语文课程标准的关键概念,其内涵是否清晰,事关语文课程改革的深入推进。语文学习任务在《普通高中语文课程标准(2017年版2020年修订)》中使用了147次,但没有明确的界定,导致语文学习任务在后续的讨论和教学实践中误用现象严重。本文根据"属加种差"的概念界定方式以及关联式与分解式相结合的概念分析方法,得出以下结论:语文学习任务是素养导向的语文实践活动,其实质是真实情境下的语言文字运用,涉及主体行为(要做什么)、达到结果(做成什么)、人际关系(与谁一起做)、时空情境(何时何地)、语言文字(用什么做)和育人导向(有什么用)六个要素。 展开更多
关键词 语文课程改革 语文学习任务 概念分析
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Soybean GmMYB76, GmMYB92, and GmMYB177 genes confer stress tolerance in transgenic Arabidopsis plants 被引量:74
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作者 Yong Liao Hong-Feng Zou Hui-wen Wang Wan-Ke Zhang Biao Ma Jin-Song Zhang Shou-yi Chen 《Cell Research》 SCIE CAS CSCD 2008年第10期1047-1060,共14页
MYB-type transcription factors contain the conserved MYB DNA-binding domain of approximately 50 amino acids and are involved in the regulation of many aspects of plant growth, development, metabolism and stress respon... MYB-type transcription factors contain the conserved MYB DNA-binding domain of approximately 50 amino acids and are involved in the regulation of many aspects of plant growth, development, metabolism and stress responses. From soybean plants, we identified 156 GmMYB genes using our previously obtained 206 MYB unigenes, and 48 were found to have full-length open-reading frames. Expressions of all these identified genes were examined, and we found that expressions of 43 genes were changed upon treatment with ABA, salt, drought and/or cold stress. Three GmMYB genes, GmMYB76, GmMYB92 and GmMYB177, were chosen for further analysis. Using the yeast assay system, GmMYB76 and GmMYB92 were found to have transactivation activity and can form homodimers. GmMYB177 did not appear to have transactivation activity but can form heterodimers with GmMYB76. Yeast onehybrid assay revealed that all the three GmMYBs could bind to cis-elements TAT AAC GGT TTT TT and CCG GAA AAA AGG AT, but with different affinity, and GmMYB92 could also bind to TCT CAC CTA CC. The transgenic Arabidopsis plants overexpressing GmMYB 76 or GmMYB177 showed better performance than the GmMYB92-transgenic plants in salt and freezing tolerance. However, these transgenic plants exhibited reduced sensitivity to ABA treatment at germination stage in comparison with the wild-type plants. The three GmMYB genes differentially affected a subset of stress-responsive genes in addition to their regulation of a common subset of stress-responsive genes. These resuits indicate that the three GmMYB genes may play differential roles in stress tolerance, possibly through regulation of stress-responsive genes. 展开更多
关键词 SOYBEAN MYB transcription factor abiotic stress tolerance
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马铃薯种植机械化关键技术与装备研究进展分析与展望 被引量:72
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作者 李紫辉 温信宇 +3 位作者 吕金庆 李季成 衣淑娟 乔丹 《农业机械学报》 EI CAS CSCD 北大核心 2019年第3期1-16,共16页
中国马铃薯种植具有面积大、范围广、地域地理复杂的特点,机械化种植是马铃薯机械化生产中关键的技术环节。马铃薯种植机械化技术包括种薯预处理、供导种、取种、清种等机械化种植关键技术。分析了中国马铃薯种植机械化技术的发展现状... 中国马铃薯种植具有面积大、范围广、地域地理复杂的特点,机械化种植是马铃薯机械化生产中关键的技术环节。马铃薯种植机械化技术包括种薯预处理、供导种、取种、清种等机械化种植关键技术。分析了中国马铃薯种植机械化技术的发展现状、特点及制约因素,总结了马铃薯种植机械化中主要关键技术,分析了整薯和切块种薯2种主要栽培方法对马铃薯播种技术的约束、影响。重点阐述了马铃薯分级、种薯分离整列拾取、零速投种、动态供种技术及装备的研究现状和发展动态,并归纳了中国、德国、荷兰、比利时、美国等国家具有技术代表性的马铃薯种植机械技术特点与性能参数;指出精量、高速、智能化大型马铃薯播种技术与装备是我国马铃薯机械化播种技术发展的核心方向,同时也需加强适应丘陵山区的小型、轻简型马铃薯机械化种植技术及装备的研究。 展开更多
关键词 马铃薯 种植 综述
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Risk factors and clinical characteristics of portal vein thrombosis after splenectomy in patients with liver cirrhosis 被引量:64
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作者 Mu-Xing Li Xu-Feng Zhang +1 位作者 Zheng-wen Liu yi Lv 《Hepatobiliary & Pancreatic Diseases International》 SCIE CAS 2013年第5期512-519,共8页
BACKGROUND:Portal vein thrombosis(PVT) is a potential lethal complication and may have negative influence on the prognosis after splenectomy in patients with liver cirrhosis.Prevention and timely detection of PVT are ... BACKGROUND:Portal vein thrombosis(PVT) is a potential lethal complication and may have negative influence on the prognosis after splenectomy in patients with liver cirrhosis.Prevention and timely detection of PVT are quite significant.There is a lack of knowledge about the clinical features and risk factors of PVT.Our study aimed to investigate the risk factors and clinical characteristics of PVT in order to figure out the high-risk individuals.METHODS:We collected the clinical data of 472 consecutive patients with non-neoplastic liver cirrhosis who had undergone splenectomy from January 2008 to December 2010 in our institution.Clinical and surgical characteristics of patients who developed PVT postoperatively and those who did not develop PVT were compared.Univariate and multivariate analyses of risk factors of PVT were performed.The mortality and rebleeding rate of the patients were also evaluated.RESULTS:Of the 472 patients,52 were excluded from the study.PVT developed in 71(71/420,16.9%) patients.Multivariate analysis revealed that wider preoperative portal vein diameter,postoperative thrombocytosis,prolonged prothrombin time and periesophagogastric devascularization were significantly correlated with PVT development [odds ratio(OR):5.701,2.807,1.850 and 2.090,respectively].The incidence of PVT in patients who took antiplatelet drugs was not lower than that in those who did not.Follow-up showed that patients in the PVT group had a tendency towards reduced overall survival but it was not statistically significant.Gastrointestinal bleeding occurred more often in the PVT group than that in the non-PVT group(P=0.044).CONCLUSIONS:Wider preoperative portal vein diameter,postoperative thrombocytosis,prolonged prothrombin time and periesophagogastric devascularization are independent risk factors of PVT.PVT is related with higher risk of postoperative gastrointestinal hemorrhage but has no significant impact on the overall survival. 展开更多
关键词 portal vein thrombosis clinical characteristics risk factor
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Identification of plasma microRNA-21 as a biomarker for early detection and chemosensitivity of non-small cell lung cancer 被引量:63
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作者 Juan Wei wen Gao Cheng-Jun Zhu yi-Qian Liu Zhu Mei Ting Cheng Yong-Qian Shu 《Chinese Journal of Cancer》 SCIE CAS CSCD 北大核心 2011年第6期407-414,共8页
Studies have shown cell-free microRNA(miRNA) circulating in the serum and plasma with specific expression in cancer,indicating the potential of using miRNAs as biomarkers for cancer diagnosis and therapy.This study wa... Studies have shown cell-free microRNA(miRNA) circulating in the serum and plasma with specific expression in cancer,indicating the potential of using miRNAs as biomarkers for cancer diagnosis and therapy.This study was to investigate whether plasma miRNA-21(miR-21) can be used as a biomarker for the early detection of non-small cell lung cancer(NSCLC) and to explore its association with clinicopathologic features and sensitivity to platinum-based chemotherapy.We used real-time RT-PCR to investigate the expression of miR-21 in the plasma of 63 NSCLC patients and 30 healthy controls and correlated the findings with early diagnosis,pathologic parameters,and treatment.Thirty-five patients(stages IIIB and IV) were evaluable for chemotherapeutic responses:11 had partial response(PR);24 had stable and progressive disease(SD+PD).Plasma miR-21 was significantly higher in NSCLC patients than in age-and sex-matched controls(P<0.001).miR-21 was related to TNM stage(P<0.001),but not related to age,sex,smoking status,histological classification,lymph node status,and metastasis(all P>0.05).This marker yielded a receiver operating characteristic(ROC) curve area of 0.775(95% CI:0.681-0.868) with 76.2% sensitivity and 70.0% specificity.Importantly,miR-21 plasma levels in PR samples were several folds lower than that in SD plus PD samples(P=0.049),and were close to that in healthy controls(P=0.130).Plasma miR-21 can serve as a circulating tumor biomarker for the early diagnosis of NSCLC and is related to the sensitivity to platinum-base chemotherapy. 展开更多
关键词 MICRORNA 非小细胞肺癌 生物标志物 药物敏感性 早期检测 血浆 miRNA 识别
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Antitumor effect of matrine in human hepatoma G2 cells by inducing apoptosis and autophagy 被引量:62
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作者 Zhang, Jun-Qiang Li, Yu-Min +7 位作者 Liu, Tao He, wen-Ting Chen, ying-Tai Chen, Xiao-Hui Li, Xun Zhou, wen-Ce yi, Jian-Feng Ren, Zhi-Jian 《World Journal of Gastroenterology》 SCIE CAS CSCD 2010年第34期4281-4290,共10页
AIM: To study the antitumor effect of matrine in human hepatoma G2 (HepG2) cells and its molecular mechanism involved in antineoplastic activities. METHODS: 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide... AIM: To study the antitumor effect of matrine in human hepatoma G2 (HepG2) cells and its molecular mechanism involved in antineoplastic activities. METHODS: 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay was used to detect viability of HepG2 cells. The effect of matrine on cell cycle was detected by flow cytometry. Annexin-V-FITC/PI double staining assay was used to detect cellular apoptosis. Cellular morphological changes were observed under an inverted phase contrast microscope. Transmission electron microscopy was performed to further examine ultrastructural structure of the cells treatedwith matrine. Monodansylcadaverine (MDC) staining was used to detect autophagy. Whether autophagy is blocked by 3-methyladenine (3-MA), an autophagy inhibitor, was evaluated. Expression levels of Bax and Beclin 1 in HepG2 cells were measured by real-time quantitative reverse transcription-polymerase chain reaction (RT-PCR).RESULTS: Matrine signif icantly inhibited the proliferation of HepG2 cells in a dose- and time-dependent manner, and induced G1-phase cell cycle arrest and apoptosis of HepG2 cells in a dose-dependent manner. The total apoptosis rate was 0.14% for HepG2 cells not treated with matrine. In contrast, the apoptosis rate was 28.91%, 34.36% and 38.80%, respectively, for HepG2 cells treated with matrine at the concentration of 0.5, 1.0 and 2.0 mg/mL. The remarkable morphological changes were observed under an inverted phase contrast microscope. Abundant cytoplasmic vacuoles with varying sizes were observed in HepG2 cells treated with matrine. Furthermore, vacuolization in cytoplasm progressively became larger and denser when the concentration of matrine was increased. Electron microscopy demonstrated formation of abundant autophagic vacuoles in HepG2 cells after matrine treatment. When the specif ic autophagic inhibitor, 3-MA, was applied, the number of autophagic vacuoles greatly decreased. MDC staining showed that the fluorescent density was higher and the number of MDC-labeled particles 展开更多
关键词 MATRINE AUTOPHAGY APOPTOSIS Bax Beclin 1 Hepatocellular carcinoma
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Expression of nuclear factor-KB in hepatocellular carcinoma and its relation with the X protein of hepatitis B virus 被引量:55
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作者 Shuang Ping Guo~1 wen Liang Wang~1 Yu Qiang Zhai~2 yi Ling Zhao~1 ~1Department of Pathology,Xijing Hospital of the Fourth Military Medical University,Xi’an,China ~2Department of Urology,the Central Hospital of Xi’an,China 《World Journal of Gastroenterology》 SCIE CAS CSCD 2001年第3期340-344,共5页
AIM In this study we investigated the relationship of the X protein of HBV and nuclear factor-κB(NF-κB)and the expression of NF-κB in human hepatocellular carcinoma tissues. METHODS Immunohistochemistry SP method w... AIM In this study we investigated the relationship of the X protein of HBV and nuclear factor-κB(NF-κB)and the expression of NF-κB in human hepatocellular carcinoma tissues. METHODS Immunohistochemistry SP method was used to detect the expression of NF-κB and the X protein of HBV in human hepatocellular carcinoma tissues of 52 cases.Gene transfection mediated by lipofectamine was used to transfect the eukaryotic expression vector pCDNA3.1-HBX of HBV x gene into human hepatocellular carcinoma cell line HCC-9204 and NF-κB was detected. RESULTS NF-κB was widely expressed in human hepatocellular carcinoma tissues in a total of 52 cases and its expression was related to the X protein of HBV.NF-κB was localized both in the cytoplasm and the nuclei of hepatocellular carcinoma cells in 11 cases which were positive for the X protein of HBV while in 41 cases negative for the X protein of HBV,NF-κB was only localized in the cytoplasm of hepatocellular carcinoma cells but translocated to the nuclei of hepatocellular carcinoma cells after the eukaryotic expression vector pCDNA3.1-HBX was transfected into HCC-9204 cells. CONCLUSION This study strongly suggests that the nuclear factor NF-κB is widely expressed in hepatocellular carcinoma tissues in different styles according to the expression of the X protein of HBV.NF-κB is abnormally activated in hepatocellular carcinoma,which is probably rélated to the X protein of HBV.The X protein of HBV can activate NF-κB to translocate into nuclei of hepatocellular carcinoma cells. 展开更多
关键词 the X protein of HBV nulcear factor-KB hepatocellular carcinoma cell
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Relationship between Carotid Atherosclerosis and Cerebral Infarction 被引量:59
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作者 Guang-wen Li Guan-yi Zheng Jin-guo Li Xu-dong Sun 《Chinese Medical Sciences Journal》 CAS CSCD 2010年第1期32-37,共6页
Objective To study the relationship between carotid atherosclerosis and cerebral infarction (CI). Methods Between November 2008 and March 2009,147 CI patients (CI group) and 48 patients with non-cerebrovascular diseas... Objective To study the relationship between carotid atherosclerosis and cerebral infarction (CI). Methods Between November 2008 and March 2009,147 CI patients (CI group) and 48 patients with non-cerebrovascular diseases (control group) were enrolled from inpatients of Neurology Department of our hospital. The diagnostic criterion of thickened carotid intima was set as 1.0 mm≤intima-media thickness (IMT) <1.5 mm and that of carotid plaque was as IMT≥1.5 mm. Carotid atherosclerosis was divided into three levels: normal intima,thickened intima,and plaque formation. The color Doppler ultrasonography data of carotid arteries in all patients were analyzed and the severity of carotid atherosclerosis was compared between the two groups. Results In the CI group,36 (24.5%) patients had normal carotid intima,22 (15.0%) had thickened carotid intima,and 89 (60.5%) had carotid plaque. In the control group,22 (45.8%) patients had normal carotid intima,4 (8.3%) had thickened carotid intima,and 22 (45.8%) had carotid plaque. The severity of carotid atherosclerosis in the CI group was higher than that in the control group (P=0.022). There was significant difference in the constitution of carotid plaque between the two groups (P=0.001); the CI group mainly had the soft plaque (55/89,61.8%),whereas the control group mainly had the hard plaque (17/22,77.3%). The first three common locations of carotid plaque in both groups were carotid bifurcation (CI group: 73.7%; control group: 64.1%),common carotid artery (CI group: 20.4%; control group: 25.6%),and internal carotid artery (CI group: 5.9%; control group: 10.3%). The location of carotid plaque between the two groups was not significantly different (P=0.438). There was no difference in the carotid inner diameter or resistance index between the two groups (P>0.05). Conclusions Carotid atherosclerosis is to some extent able to reveal the atherosclerotic condition of cerebral arteries and act as an important predictor for the risk of CI. The color Doppler ultrasonography of carotid 展开更多
关键词 carotid atherosclerosis cerebral infarction intima-media thickness color Doppler ultrasonography
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四川盆地二叠系火山岩岩相与储层特征 被引量:58
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作者 文龙 李亚 +5 位作者 易海永 刘鑫 张本健 邱玉超 周刚 张玺华 《天然气工业》 EI CAS CSCD 北大核心 2019年第2期17-27,共11页
为了给四川盆地火山岩气藏下一步的勘探部署提供依据,综合利用钻井录井、分析化验、测井及地震等资料,在对该盆地二叠系火山岩分类的基础上,研究了不同类型火山岩的岩性特征、岩相特征与岩相分布、储层特征,并确定了控制火山岩储层发育... 为了给四川盆地火山岩气藏下一步的勘探部署提供依据,综合利用钻井录井、分析化验、测井及地震等资料,在对该盆地二叠系火山岩分类的基础上,研究了不同类型火山岩的岩性特征、岩相特征与岩相分布、储层特征,并确定了控制火山岩储层发育的主要因素。研究结果表明:①该盆地火山岩可综合划分为火山熔岩、火山碎屑熔岩、火山碎屑岩及沉火山碎屑岩4大类,主要发育玄武岩、角砾熔岩、含凝灰角砾熔岩、凝灰岩和沉凝灰岩等岩石类型;②该盆地内大面积分布溢流相、喷溢相和火山沉积相等3种火山岩相类型,其中溢流相主要发育玄武岩,喷溢相主要发育火山碎屑熔岩,火山沉积相主要发育凝灰岩及沉凝灰岩等;③火山岩储层岩性主要为火山碎屑熔岩和玄武岩,其中火山碎屑熔岩主要发育脱玻化微孔、溶蚀孔,为中孔、低渗的孔隙型储层,玄武岩主要发育裂缝及溶孔,为基质孔隙度较低的孔隙—裂缝型储层;④火山岩储层控制因素主要为岩性、岩相、后期流体改造作用和构造作用,其中火山碎屑熔岩在快速冷凝的过程中脱玻化形成大量弥散状微孔,为后期进一步溶蚀增孔提供了有利条件,溶蚀等成岩作用及裂缝发育使储层物性变好。结论认为,四川盆地二叠系火山岩储层的平面展布主要受岩相控制,川西南部雅安—乐山—屏山地区主要发育孔隙—裂缝型玄武岩储层,成都—简阳—三台地区主要发育孔隙型火山碎屑熔岩储层。 展开更多
关键词 四川盆地 二叠纪 火山岩 分类 岩性 岩相 储集层特征 后期流体改造作用 构造作用
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Blockage of transforming growth factor β receptors prevents progression of pig serum-induced rat liver fibrosis 被引量:51
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作者 WeiJiang Chang-QingYang wen-BinLiu yi-QingWang Bo-MingHe Ji-YaoWang 《World Journal of Gastroenterology》 SCIE CAS CSCD 2004年第11期1634-1638,共5页
AIM: To test the hypothesis that introduction of antisense TβR Ⅰ and TβR Ⅱ eukaryotic expressing plasmids into a rat model of immunologically induced liver fibrosis might block the action of TGF-β1 and halt the p... AIM: To test the hypothesis that introduction of antisense TβR Ⅰ and TβR Ⅱ eukaryotic expressing plasmids into a rat model of immunologically induced liver fibrosis might block the action of TGF-β1 and halt the progression of liver fibrosis. METHODS: RT-Nest-PCR and gene recombination techniques were used to construct rat antisense TβR Ⅰ and TβR Ⅱ recombinant plasmids which could be expressed in eukaryotic cells. The recombinant plasmids and empty vector (pcDNA3) were encapsulated by glycosyl-poly-L-lysine and then transducted into rats of pig serum-induced liver fibrosis model. Expression of exogenously transfected gene was assessed by Northern blot, and hepatic expressions of TβR Ⅰ and TβR Ⅱ were evaluated by RT-PCR and Western blot.We also performed ELISA for serum TGF-β1, hydroxyproline of hepatic tissues, immunohistochemistry for collagen types Ⅰ and Ⅲ, and VG staining for pathological study of the liver tissues. RESULTS: The exogenous antisense TβR Ⅰ and TβR Ⅱ plasmids could be well expressed in vivo, and block mRNA and protein expression of TβR Ⅰ and TβR Ⅱ in the fibrotic liver at the level of mRNA respectively. These exogenous plasmid expressions reduced the level of TGF-β1 (antisense TβR Ⅰ group 23.998+3.045 ng/mL, antisense TβR Ⅱ group 23.156+3.131 ng/mL, disease control group 32.960+3.789 ng/mL; F-=-38.19, 36.73, P<0.01). Compared with disease control group, the contents of hepatic hydroxyproline (antisense TβR Ⅰ group 0.169+0.015 mg/g liver, antisense TβR Ⅱ group 0.167+0.009 mg/g liver, disease control group 0.296+0.026 mg/g liver; F=14.39, 15.48, P<0.01) and the deposition of collagen types Ⅰ and Ⅲ decreased in the two antisense treatment groups(antisense TβR Ⅰ group, collagen type Ⅰ 669.90+50.67, collagen type Ⅲ 657.29+49.48; antisense TβR Ⅱ group, collagen type Ⅰ 650.26+51.51, collagen type Ⅲ 661.58+55.28; disease control group, collagen type I 1209.44+116.60, collagen type Ⅲ 1175.14+121.44; F=15.48 to 74.89, P<0.01). Their expres 展开更多
关键词 生长素 Β受体 预防措施 免疫血清 肝纤维化 肝脏疾病
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Spectrum and antimicrobial resistance of common pathogenic bacteria isolated from patients with acute exacerbation of chronic obstructive pulmonary disease in mainland of China 被引量:56
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作者 YE Feng HE Li-xian +6 位作者 CAI Bo-qiang wen Fu-qiang CHEN Bai-yi Mangunnegoro Hadiarto CHEN Rong-chang YUAN Jin-ping SUN Hong-li 《Chinese Medical Journal》 SCIE CAS CSCD 2013年第12期2207-2214,共8页
Background Bacteria-induced respiratory infection has been long considered to be the major cause of acute exacerbation of chronic obstructive pulmonary disease (AECOPD).Therefore,a clear picture about the distributi... Background Bacteria-induced respiratory infection has been long considered to be the major cause of acute exacerbation of chronic obstructive pulmonary disease (AECOPD).Therefore,a clear picture about the distribution and drug-resistance of pathogenic bacteria in the lower airways should be helpful for treatment of the disease.So far,data on this topic among Chinese are lacking.Methods A surveillance study was performed in consecutive patients with AECOPD at five areas in China between October 2006 and April 2008.The sputum from these patients was cultured and isolated for bacteria.Agar dilution method was used to determine the minimal inhibitory concentrations (MICs) of levofloxacin and other 15 antibiotics against these strains.Results Three hundred and fifty-nine pathogenic bacterial strains were isolated among 884 patients with AECOPD.The predominant bacteria were Pseudomonas aeruginosa (21.7%),Klebsiella pneumoniae (12.3%),Haemophilus influenzae (14.2%) and Streptococcus pneumoniae (11.7%),followed by Haemophilus parainfluenzae (9.5%),Acinetobacter baumannii (7.8%),Moraxella catarrhalis (6.4%) and Escherichia coli (3.6%).The majority of bacterial pathogens isolated in this study were susceptible to fluoroquinolones,ceftazidime,cefepime and imipenem.Conclusions Gram-negative bacilli are the leading pathogens in patients with AECOPD in China.Haemophilus parainfluenzae may be one of the most important pathogens in AECOPD.This study provides evidence for local surveillance of AECOPD pathogens and appropriate choice of antimicrobials in China. 展开更多
关键词 chronic obstructive pulmonary disease acute exacerbation bacteriology antibiotics drug resistance
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1990-2016年中国青少年死亡率及主要死因变化 被引量:54
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作者 徐荣彬 温勃 +4 位作者 宋逸 罗冬梅 董彦会 董彬 马军 《中华预防医学杂志》 CAS CSCD 北大核心 2018年第8期802-808,共7页
目的 分析1990—2016年中国10~19岁青少年死亡率及主要死亡原因变化。方法 利用2016年全球疾病负担研究(GBD 2016)中中国10~19岁青少年死亡数据,描述1990—2016年中国青少年死亡率变化,并比较1990和2016年前15位死因。结果 1990... 目的 分析1990—2016年中国10~19岁青少年死亡率及主要死亡原因变化。方法 利用2016年全球疾病负担研究(GBD 2016)中中国10~19岁青少年死亡数据,描述1990—2016年中国青少年死亡率变化,并比较1990和2016年前15位死因。结果 1990—2016年,中国10~19岁青少年全死因死亡率从102.5/10万下降至41.2/10万,约降至2016年全球平均水平(78.6/10万)的50%,但仍是2016年高收入国家平均水平(24.3/10万)的近2倍;女生死亡率下降幅度高于男生(68.7%比54.7%),10~14岁高于15~19岁(62.1%比57.1%)。26年间,前15位死因的死亡率均有大幅下降,其中传染病、孕产妇疾病和营养性疾病死亡率下降幅度最大(下降78.1%),其死亡构成比由11.1%降至6.1%,非传染性疾病和伤害的死亡率下降幅度相对较小(分别为58.2%和57.3%),其死亡构成比分别从33.4%和55.6%上升至34.8%和59.1%。前五位死因由1990年的溺水(死亡率17.39/10万,死亡构成比17.0%)、道路伤害(14.77/10万,14.4%)、自我伤害(11.44/10万,11.2%)、白血病(5.48/10万,5.4%)和人际间暴力(3.12/10万,3.0%)变为2016年的道路伤害(9.27/10万,22.5%)、溺水(6.83/10万,16.6%)、白血病(2.73/10万,6.6%)、自我伤害(2.53/10万,6.2%)和先天性出生缺陷(1.76/10万,4.3%),2016年结核病、中毒和风湿性心脏病跌出前15名死因。结论 中国青少年死亡率大幅下降,但仍高于发达国家。1990年以来,道路伤害和溺水等伤害一直是青少年最主要死因,其次是慢性非传染性疾病。 展开更多
关键词 青少年 死亡原因 死亡率
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The Chinese Society of Clinical Oncology(CSCO)clinical guidelines for the diagnosis and treatment of nasopharyngeal carcinoma 被引量:44
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作者 Ling-Long Tang Yu-Pei Chen +37 位作者 Chuan-Ben Chen Ming-Yuan Chen Nian-Yong Chen Xiao-Zhong Chen Xiao-Jing Du wen-Feng Fang Mei Feng Jin Gao Fei Han Xia He Chao-Su Hu De-sheng Hu Guang-Yuan Hu Hao Jiang Wei Jiang Feng Jin Jin-yi Lang Jin-Gao Li Shao-Jun Lin Xu Liu Qiu-Fang Liu Lin Ma Hai-Qiang Mai Ji-Yong Qin Liang-Fang Shen ying Sun Pei-Guo Wang Ren-Sheng Wang Ruo-Zheng Wang Xiao-Shen Wang ying Wang Hui Wu Yun-Fei Xia Shao-wen Xiao Kun-Yu Yang Jun-Lin yi Xiao-Dong Zhu Jun Ma 《Cancer Communications》 SCIE 2021年第11期1195-1227,共33页
Nasopharyngeal carcinoma(NPC)is a malignant epithelial tumor originating in the nasopharynx and has a high incidence in Southeast Asia and North Africa.To develop these comprehensive guidelines for the diagnosis and m... Nasopharyngeal carcinoma(NPC)is a malignant epithelial tumor originating in the nasopharynx and has a high incidence in Southeast Asia and North Africa.To develop these comprehensive guidelines for the diagnosis and management of NPC,the Chinese Society of Clinical Oncology(CSCO)arranged a multi-disciplinary team comprising of experts from all sub-specialties of NPC to write,discuss,and revise the guidelines.Based on the findings of evidencebased medicine in China and abroad,domestic experts have iteratively developed these guidelines to provide proper management of NPC.Overall,the guidelines describe the screening,clinical and pathological diagnosis,staging and risk assessment,therapies,and follow-up of NPC,which aim to improve the management of NPC. 展开更多
关键词 Chinese Society of Clinical Oncology CSCO Nasopharyngeal carcinoma Diagnosis STAGING Risk RADIOTHERAPY CHEMOTHERAPY Surgery IMMUNOTHERAPY
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碳中和目标下的若干地球系统科学和技术问题分析 被引量:44
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作者 蔡兆男 成里京 +24 位作者 李婷婷 郑循华 王林 韩圣慧 王凯 屈侠 江飞 张永雨 朱建华 龙上敏 孙扬 贾炳浩 袁文平 张天一 张晴 谢瑾博 朱家文 刘志强 吴琳 杨东旭 魏科 吴林 张稳 刘毅 曹军骥 《中国科学院院刊》 CSSCI CSCD 北大核心 2021年第5期602-613,共12页
碳中和作为21世纪最大规模的有序人类活动,亟待科学应对。文章从地球系统科学角度,讨论了支撑“碳达峰、碳中和”目标的大气、陆地和海洋相关的地球系统科学中的若干科学和技术问题及现存的知识不足。从地球系统模式、气候监测指标、温... 碳中和作为21世纪最大规模的有序人类活动,亟待科学应对。文章从地球系统科学角度,讨论了支撑“碳达峰、碳中和”目标的大气、陆地和海洋相关的地球系统科学中的若干科学和技术问题及现存的知识不足。从地球系统模式、气候监测指标、温室气体监测技术、碳源/汇核算方法体系等方面,阐述了支撑碳中和的关键技术手段及现存的问题。基于目前存在的挑战和不足,建议深入理解气候系统多圈层相互作用过程和机制,完善地球系统理论与模式,从多圈层角度加强“碳达峰、碳中和”目标和气候变化理论基础;自主构建气候变化监测指标系统,研发温室气体监测与核查手段和平台,为碳中和目标提供先进的技术手段支撑。 展开更多
关键词 碳中和 碳源 碳汇 温室气体 气候变化 地球系统模式 气候监测
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Inhibition on the production of collagen type Ⅰ, Ⅲ of activated hepatic stellate cells by antisense TIMP-1 recombinant plasmid 被引量:42
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作者 wen-Bin Liu Chang-Qing Yang Wei Jiang yi-Qing Wang Jing-Sheng Guo Bo-Ming He Ji-Yao Wang Division of Gastroenterology, Zhongshan Hospital, Fudan University, Shanghai 200032, China 《World Journal of Gastroenterology》 SCIE CAS CSCD 2003年第2期316-319,共4页
AIM: To investigate the inhibition effects on the productionof collagen type I, Ⅲ secreted by activated rat hepatic stellatecells (rHSCs) by antisense tissue inhibitors of metalloproteinase1 (TIMP-1) recombinant plas... AIM: To investigate the inhibition effects on the productionof collagen type I, Ⅲ secreted by activated rat hepatic stellatecells (rHSCs) by antisense tissue inhibitors of metalloproteinase1 (TIMP-1) recombinant plasmid through elevating interstitialcollagenase activity.METHODS: rHSCs were extracted from normal rat liverby pronase and collagenase digestion and purified bycentrifugal elutriation, and were cultured on plastic dishesuntil they were activated to a myofibroblastic phenotypeafter 7-10 days. RT-Nest-PCR and gene recombinanttechniques were used to construct the rat antisense TIMP-1 recombinant plasmids which can express in eucaryoticcells. The recombinant plasmid and the pcDNA3 emptyplasmid were transfected in rHSCs by Effectene (QIAGEN)separately. Cells were selected after growing in DMEMcontaining 400 μg/ml G418 for 2-3 weeks. Expression ofexogenous gene was assessed by Northern blot, andexpression oflIMP-1 in rHSCs was determined by Northernblot and Western blot. We tested the interstitial collagenaseactivity with FITC-labled type I collagen as substrate.Ultimately, we quantified the type Ⅰ, Ⅲ collagen byWestern blot.RESULTS: The exogenous antisense TIMP-1 recombinantplasmid could be expressed in rHSCs well, which couldblock the expression of TIMP-1 greatly, the ratio of TIMP-1/GAPDH was 0.67, 2.41, and 2.97 separately at mRNAlevel (P<0.05); the ratio of TIMP-1/β-actin was 0.31, 0.98and 1.32 separately at protein level (P<0.05); It mightelevate active and latent interstitial collagenase activity,the collagenase activity was 0.3049, 0.1411 and 0.1196respectively. (P<0.05), which led to promotion thedegradation of type Ⅰ, Ⅲ collagen, the ratio of collagen I/β-actin was 0.63, 1.78 and 1.92 separately (P<0.05); andthe ratio of collagen Ⅲ/β-actin was 0.59, 1.81 and 1.98separately (P<0.05).CONCLUSION: These data shows that the antisense TIMP-1 recombinant plasmid has the inhibitory effects on theproduction of type Ⅰ, Ⅲ collagens secreted by activatedrHSCs in vitro. It could be 展开更多
关键词 胶原质 肝星形细胞 细胞因子 反义金属蛋白酶-1 重组质粒 胶原酶 肝纤维化
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森林类型遥感分类及变化监测研究进展 被引量:37
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作者 颜伟 周雯 +1 位作者 易利龙 田昕 《遥感技术与应用》 CSCD 北大核心 2019年第3期445-454,共10页
森林是陆地生态系统最主要的植被类型,利用遥感技术对森林类型分类识别和动态监测对于全球碳循环研究和森林资源可持续发展具有重要意义。梳理了森林遥感分类的主要经典方法,从传统的基于像元的分类方法、面向对象方法再到新型基于红边... 森林是陆地生态系统最主要的植被类型,利用遥感技术对森林类型分类识别和动态监测对于全球碳循环研究和森林资源可持续发展具有重要意义。梳理了森林遥感分类的主要经典方法,从传统的基于像元的分类方法、面向对象方法再到新型基于红边波谱信息以及基于深度学习的分类方法,并详细介绍了现有的各种方法的应用案例及其优势。最后,提出了现阶段森林遥感分类和遥感变化监测研究中的局限性,为新形势下的森林资源动态监管提供借鉴。 展开更多
关键词 多源遥感数据 森林分类 深度学习 变化监测
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Wet Cupping Therapy Improves Local Blood Perfusion and Analgesic Effects in Patients with Nerve-Root Type Cervical Spondylosis 被引量:36
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作者 MENG Xiang-wen WANG ying +6 位作者 PIAO Sheng-ai LV wen-tao ZHU Cheng-hui MU Ming-yuan LI Dan-dan LIU Hua-peng GUO yi 《Chinese Journal of Integrative Medicine》 SCIE CAS CSCD 2018年第11期830-834,共5页
Objective: To observe wet cupping therapy(WCT) on local blood perfusion and analgesic effects in patients with nerve-root type cervical spondylosis(NT-CS). Methods: Fifty-seven NT-CS patients were randomly divid... Objective: To observe wet cupping therapy(WCT) on local blood perfusion and analgesic effects in patients with nerve-root type cervical spondylosis(NT-CS). Methods: Fifty-seven NT-CS patients were randomly divided into WCT group and Jiaji acupoint-acupuncture(JA) group according a random number table. WCT group(30 cases) was treated with WCT for 10 min, and JA group(27 cases) was treated with acupuncture for 10 min. The treatment efficacies were evaluated with a Visual Analogue Scale(VAS). Blood perfusion at Dazhui(GV 14) and Jianjing(GB 21) acupoints(affected side) was observed with a laser speckle flowmetry, and its variations before and after treatment in both groups were compared as well. Results: In both groups, the VAS scores significantly decreased after the intervention(P〈0.01), while the blood perfusion at the two acupoints significantly increased after intervention(P〈0.05); however, the increasement magnitude caused by WCT was obvious compared with JA(P〈0.05). Conclusion: WCT could improve analgesic effects in patients with NT-CS, which might be related to increasing local blood perfusion of acupunct points. 展开更多
关键词 wet cupping nerve-root type cervical spondylosis blood perfusion amount acupuncture Jiaji acupoint
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