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Clinical and biochemical indexes from 2019-nCoV infected patients linked to viral loads and lung injury 被引量:174
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作者 Yingxia Liu Yang Yang +19 位作者 Cong Zhang Fengming Huang Fuxiang Wang Jing Yuan Zhaoqin Wang Jinxiu Li Jianming Li Cheng Feng Zheng Zhang Lifei Wang Ling Peng Li Chen Yuhao Qin Dandan Zhao Shuguang tan Lu Yin Jun Xu Congzhao Zhou Chengyu Jiang Lei Liu 《Science China(Life Sciences)》 SCIE CAS CSCD 2020年第3期364-374,共11页
The outbreak of the 2019-nCoV infection began in December 2019 in Wuhan,Hubei province,and rapidly spread to many provinces in China as well as other countries.Here we report the epidemiological,clinical,laboratory,an... The outbreak of the 2019-nCoV infection began in December 2019 in Wuhan,Hubei province,and rapidly spread to many provinces in China as well as other countries.Here we report the epidemiological,clinical,laboratory,and radiological characteristics,as well as potential biomarkers for predicting disease severity in 2019-nCoV-infected patients in Shenzhen,China.All 12 cases of the 2019-nCoV-infected patients developed pneumonia and half of them developed acute respiratory distress syndrome (ARDS).The most common laboratory abnormalities were hypoalbuminemia,lymphopenia,decreased percentage of lymphocytes (LYM) and neutrophils (NEU),elevated C-reactive protein (CRP) and lactate dehydrogenase (LDH),and decreased CD8 count.The viral load of 2019-nCoV detected from patient respiratory tracts was positively linked to lung disease severity.ALB,LYM,LYM (%),LDH,NEU (%),and CRP were highly correlated to the acute lung injury.Age,viral load,lung injury score,and blood biochemistry indexes,albumin (ALB),CRP,LDH,LYM (%),LYM,and NEU (%),may be predictors of disease severity.Moreover,the Angiotensin Ⅱlevel in the plasma sample from 2019-nCoV infected patients was markedly elevated and linearly associated to viral load and lung injury.Our results suggest a number of potential diagnosis biomarkers and angiotensin receptor blocker (ARB) drugs for potential repurposing treatment of 2019-nCoV infection. 展开更多
关键词 2019-nCoV AngiotensinⅡ ARDS
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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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The origin, transmission and clinical therapies on coronavirus disease 2019(COVID-19) outbreak——an update on the status 被引量:143
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作者 Yan-Rong Guo Qing-Dong Cao +6 位作者 Zhong-Si Hong Yuan-Yang tan Shou-Deng Chen Hong-Jun Jin Kai-Sen tan De-Yun Wang Yan Yan 《Military Medical Research》 SCIE CAS CSCD 2020年第1期93-103,共11页
An acute respiratory disease,caused by a novel coronavirus(SARS-CoV-2,previously known as 2019-nCoV),the coronavirus disease 2019(COVID-19)has spread throughout China and received worldwide attention.On 30 January 202... An acute respiratory disease,caused by a novel coronavirus(SARS-CoV-2,previously known as 2019-nCoV),the coronavirus disease 2019(COVID-19)has spread throughout China and received worldwide attention.On 30 January 2020,World Health Organization(WHO)officially declared the COVID-19 epidemic as a public health emergency of international concern.The emergence of SARS-CoV-2,since the severe acute respiratory syndrome coronavirus(SARSCoV)in 2002 and Middle East respiratory syndrome coronavirus(MERS-CoV)in 2012,marked the third introduction of a highly pathogenic and large-scale epidemic coronavirus into the human population in the twenty-first century.As of 1 March 2020,a total of 87,137 confirmed cases globally,79,968 confirmed in China and 7169 outside of China,with 2977 deaths(3.4%)had been reported by WHO.Meanwhile,several independent research groups have identified that SARS-CoV-2 belongs toβ-coronavirus,with highly identical genome to bat coronavirus,pointing to bat as the natural host.The novel coronavirus uses the same receptor,angiotensin-converting enzyme 2(ACE2)as that for SARS-CoV,and mainly spreads through the respiratory tract.Importantly,increasingly evidence showed sustained human-tohuman transmission,along with many exported cases across the globe.The clinical symptoms of COVID-19 patients include fever,cough,fatigue and a small population of patients appeared gastrointestinal infection symptoms.The elderly and people with underlying diseases are susceptible to infection and prone to serious outcomes,which may be associated with acute respiratory distress syndrome(ARDS)and cytokine storm.Currently,there are few specific antiviral strategies,but several potent candidates of antivirals and repurposed drugs are under urgent investigation.In this review,we summarized the latest research progress of the epidemiology,pathogenesis,and clinical characteristics of COVID-19,and discussed the current treatment and scientific advancements to combat the epidemic novel coronavirus. 展开更多
关键词 Clinical characteristics Coronavirus disease 2019(COVID-19) ORIGIN SARS-CoV-2 Therapy TRANSMISSION
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亚洲高血压合并左心室肥厚诊治专家共识 被引量:130
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作者 孙宁玲 Jaw-Wen Chen +10 位作者 王继光 谢良地 陈鲁原 牟建军 孙跃民 Chern-En Chiang Cheuk-Man Yu Huay Cheem tan Razali Omar 霍勇 《中华高血压杂志》 CAS CSCD 北大核心 2016年第7期619-627,600,共9页
流行病学调查发现,高血压合并左心室肥厚(left ventricular hypertrophy,LVH)的比例很高,由于诊断标准的差异,不同研究LVH的检出率差别也很大。高血压合并LVH显著增加心血管事件的风险,但临床实践中仍关注不足,诊疗欠规范。亚洲高血压... 流行病学调查发现,高血压合并左心室肥厚(left ventricular hypertrophy,LVH)的比例很高,由于诊断标准的差异,不同研究LVH的检出率差别也很大。高血压合并LVH显著增加心血管事件的风险,但临床实践中仍关注不足,诊疗欠规范。亚洲高血压合并左心室肥厚诊治专家共识在LVH的诊断流程、治疗策略和患者随访等方面详细地进行了文献回顾和方案推荐,对于规范高血压防治有重要意义。 展开更多
关键词 心血管事件 诊断流程 HYPERTROPHY Β受体阻滞剂 向心性肥厚 左心室质量 专家共识 降压药物 超声心动图 钙拮抗剂
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LncRNA-mediated posttranslational modifications and reprogramming of energy metabolism in cancer 被引量:129
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作者 Yue-Tao tan Jin-Fei Lin +3 位作者 Ting Li Jia-Jun Li Rui-Hua Xu Huai-Qiang Ju 《Cancer Communications》 SCIE 2021年第2期109-120,共12页
Altered metabolism is a hallmark of cancer,and the reprogramming of energy metabolism has historically been considered a general phenomenon of tumors.It is well recognized that long noncoding RNAs(lncRNAs)regulate ene... Altered metabolism is a hallmark of cancer,and the reprogramming of energy metabolism has historically been considered a general phenomenon of tumors.It is well recognized that long noncoding RNAs(lncRNAs)regulate energy metabolism in cancer.However,lncRNA-mediated posttranslational modifications and metabolic reprogramming are unclear at present.In this review,we summarized the current understanding of the interactions between the alterations in cancer-associated energy metabolism and the lncRNA-mediated posttranslational modifications of metabolic enzymes,transcription factors,and other proteins involved in metabolic pathways.In addition,we discuss the mechanisms through which these interactions contribute to tumor initiation and progression,and the key roles and clinical significance of functional lncRNAs.We believe that an in-depth understanding of lncRNA-mediated cancer metabolic reprogramming can help to identify cellular vulnerabilities that can be exploited for cancer diagnosis and therapy. 展开更多
关键词 cancer metabolism ENZYME long noncoding RNA metabolic reprogramming posttranslational modification
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Effect of phosphorylation of MAPK and Stat3 and expression of c-fos and c-jun proteins on hepatocarcinogenesis and their clinical significance 被引量:76
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作者 De Yun Feng Hui Zheng +1 位作者 Yi tan Rui Xue Cheng Department of Pathology, Hunan Medical University, Changsha 410078, Hunan Province, China New England Biolab, MA, USA 《World Journal of Gastroenterology》 SCIE CAS CSCD 2001年第1期33-36,共4页
AIM To study the effect of phosphorylation ofMAPK and Stat3 and the expression of c-fos andc-jun proteins on hepatocellular carcinogenesisand their clinical significance.METHODS SP immunohistochemistry was usedto dete... AIM To study the effect of phosphorylation ofMAPK and Stat3 and the expression of c-fos andc-jun proteins on hepatocellular carcinogenesisand their clinical significance.METHODS SP immunohistochemistry was usedto detect the expression of p42/44MAPK, p-Stat3,c-fos and c-jun proteins in 55 hepatocellularcarcinomas (HCC) and their surrounding livertissues.RESULTS The positive rates and expressionlevels of p42/44MAPK, p-Stat3, c-fos and c-junproteins in HCCs were significantly higher thanthose in pericarcinomatous liver tissues (PCLT).A positive correlation was observed between theexpression of p42/44MAPK and c-fos proteins, andbetween p-Stat3 and c-jun, but there was nosignificant correlation between p42/44MAPK and p-Stat3 in HCCs and their surrounding livertissues.CONCLUSION The abnormalities of Ras/Rat/MAPK and JAKs/ Stat3 cascade reaction maycontribute to malignant transformation ofhepatocytes. Hepatocytes which are positive forp42/ 44MAPK, c-fos or c-jun proteins may bepotential malignant pre-cancerous cells.Activation of MAPK and Stat3 proteins may be anearly event in hepatocellular carcinogenesis. 展开更多
关键词 liver neoplasms MITOGEN-ACTIVATED protein KINASES signal transduction TRANS-ACTIVATORS ONCOGENES immunohistochemistry PRECANCEROUS conditions
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Chemical characteristics of PM_(2.5) during a typical haze episode in Guangzhou 被引量:73
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作者 tan Jihua DUAN Jingchun +4 位作者 HE Kebin MA Yongliang DUAN Fengkui CHEN Yuan FU Jiamo 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2009年第6期774-781,共8页
The chemical characteristics(water-soluble ions and carbonaceous species) of PM2.5 in Guangzhou were measured during a typical haze episode.Most of the chemical species in PM2.5 showed significant difference between... The chemical characteristics(water-soluble ions and carbonaceous species) of PM2.5 in Guangzhou were measured during a typical haze episode.Most of the chemical species in PM2.5 showed significant difference between normal and haze days.The highest contributors to PM2.5 were organic carbon(OC),nitrate,and sulfate in haze days and were OC,sulfate,and elemental carbon(EC) in normal days.The concentrations of secondary species such as,NO3^-,SO4^2-,and NH4^+ in haze days were 6.5,3.9,and 5.3 times higher than those in normal days,respectively,while primary species(EC,Ca^2+,K^+) show similar increase from normal to haze days by a factor about 2.2-2.4.OC/EC ratio ranged from 2.8 to 6.2 with an average of 4.7 and the estimation on a minimum OC/EC ratio showed that SOC(secondary organic carbon) accounted more than 36.6% for the total organic carbon in haze days.The significantly increase in the secondary species(SOC,NO3^-,SO4^2-,and NH4^+),especially in NO3^-,caused the worst air quality in this region.Simultaneously,the result illustrated that the serious air pollution in haze episodes was strongly correlated with the meteorological conditions.During the sampling periods,air pollution and visibility had a good relationship with the air mass transport distance;the shorter air masses transport distance,the worse air quality and visibility in Guangzhou,indicating the strong domination of local sources contributing to haze formation.High concentration of the secondary aerosol in haze episodes was likely due to the higher oxidation rates of sulfur and nitrogen species. 展开更多
关键词 PM2.5 haze episode water-soluble inorganic ions organic carbon elemental carbon GUANGZHOU
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Size distributions and sources of elements in particulate matter at curbside,urban and rural sites in Beijing 被引量:71
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作者 Jingchun Duan Jihua tan +2 位作者 Shulan Wang Jimin Hao Fahe Chai 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2012年第1期87-94,共8页
Size distributions of 29 elements in aerosols collected at urban,rural and curbside sites in Beijing were studied.High levels of Mn,Ni,As,Cd and Pb indicate the pollution of toxic heavy metals cannot be neglected in B... Size distributions of 29 elements in aerosols collected at urban,rural and curbside sites in Beijing were studied.High levels of Mn,Ni,As,Cd and Pb indicate the pollution of toxic heavy metals cannot be neglected in Beijing.Principal component analysis (PCA) indicates 4 sources of combustion emission,crust related sources,traffic related sources and volatile species from coal combustion.The elements can be roughly divided into 3 groups by size distribution and enrichment factors method (EFs).Group 1 elements are crust related and mainly found within coarse mode including Al,Mg,Ca,Sc,Ti,Fe,Sr,Zr and Ba;Group 2 elements are fossil fuel related and mostly concentrated in accumulation mode including S,As,Se,Ag,Cd,Tl and Pb;Group 3 elements are multi-source related and show multi-mode distribution including Be,Na,K,Cr,Mn,Co,Ni,Cu,Zn,Ga,Mo,Sn and Sb.The EFs of Be,S,Cr,Co,Ni,Cu,Ga,Se,Mo,Ag,Cd,Sb,Tl and Pb show higher values in winter than in summer indicating sources of coal combustion for heating in winter.The abundance of Cu and Sb in coarse mode is about 2–6 times higher at curbside site than at urban site indicating their traffic sources.Coal burning may be the major source of Pb in Beijing since the phase out of leaded gasoline,as the EFs of Pb are comparable at both urban and curbside sites,and about two times higher in winter than that in summer. 展开更多
关键词 ELPI enrichment factor curbside atmosphere heavy metal
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Crustal deformation on the Chinese mainland during 1998—2004 based on GPS data 被引量:62
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作者 Zhao Bin Huang Yong +3 位作者 Zhang Caihong Wang Wei tan Kai Du Rinlin 《Geodesy and Geodynamics》 2015年第1期7-15,共9页
This study focuses on resolving moderate amounts of crustal motion at the continental scale based on a large volume of global positioning system(GPS) data during 1998e2014. A state-of-the-art GPS processing strategy... This study focuses on resolving moderate amounts of crustal motion at the continental scale based on a large volume of global positioning system(GPS) data during 1998e2014. A state-of-the-art GPS processing strategy was used to resolve position time series and velocities from carrier beat phases for all available data. Position time series were closely analyzed to estimate linear constant, coseismic displacements, postseismic motions, and other parameters. We present coseismic offsets inferred from the GPS data for the 2010 Yushu and 2014 Yutian earthquakes, and also illustrate transient postseismic motions following the 2001 Kokoxili, 2008 Wenchuan, and 2011 Tohoku-Oki earthquakes. Since not all GPS position time series dominated by postseismic motions can be modeled and corrected reasonably, we present contemporary horizontal velocities from 2009 to 2014 for campaign stations and from 1998 to 2014 for continuous stations, irrespective of postseismic deformations. Our study concludes that we need to accumulate observations over a greater duration and apply accurate postseismic modeling to correct for transient displacement in order to resolve reasonable interseismic velocity. 展开更多
关键词 Velocity field Coseismic deformation Postseismic deformation Error analysis Chinese mainland
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Black carbon aerosols and their radiative properties in the Pearl River Delta region 被引量:60
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作者 WU Dui MAO JieTai +9 位作者 DENG XueJiao TIE XueXi ZHANG YuanHang ZENG LiMin LI Fei tan HaoBo BI XueYan HUANG XiaoYing CHEN Jing DENG Tao 《Science China Earth Sciences》 SCIE EI CAS 2009年第8期1152-1163,共12页
The climatic and environmental effects of atmospheric aerosols are a hot topic in global science community, and radiative properties of the aerosols are one of the important parameters in assessing climatic change. He... The climatic and environmental effects of atmospheric aerosols are a hot topic in global science community, and radiative properties of the aerosols are one of the important parameters in assessing climatic change. Here we studied the black carbon concentration and absorption coefficient measured with aethalometers, scattering coefficient measured with nephelometers, and single scattering albedo derived at an atmospheric composition watch station in Guangzhou from 2004 to 2007. Our main results are as follows. The data of black carbon concentration and absorption coefficients measured with instruments cannot be directly used until they are measured in parallel with internationally accepted instruments for comparison, calibration, and reduction. After evaluation of the data, the result shows that the monthly mean of BC concentration varies 3.1―14.8 μg·m-3 and the concentration decreases by about 1 μg·m-3 in average over the four years; It is higher in the dry season with a multi-year mean of 8.9 μg/m3 and lower in the rainy season with a multi-year mean of 8.0 μg·m-3; The extreme maximum of monthly mean concentration occurred in December 2004 and extreme minimum in July 2007, and a 4-year mean is 8.4 μg·m-3. It is also shown that monthly mean scattering coefficient derived varies 129 -565 Mm-1, monthly mean absorption coefficient 32-139 Mm-1, and monthly mean single scattering albedo 0.71-0.91, with annual mean values of 0.80, 0.82, 0.79 and 0.84 for 2004, 2005, 2006 and 2007, respectively. Three instruments were used to take simultaneous measurements of BC in PM10, PM2.5, and PM1 and the results showed that PM2.5 took up about 90% of PM10 and PM1 accounted for about 68% of PM2.5, and BC aerosols are mainly present in fine particulates. The variability of BC concentrations is quite consistent between the Nancun station (141 m above sea level) and the Panyu station (13 m above sea level), which are 8 km apart from each other. The concentration in higher altitude station (Panyu) is consistently lower than 展开更多
关键词 PEARL River Delta BC AEROSOLS SCATTERING COEFFICIENT absorption COEFFICIENT single SCATTERING ALBEDO
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The First Imported Case of Monkeypox in the Mainland of China—Chongqing Municipality,China,September 16,2022 被引量:56
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作者 Hua Zhao Wenling Wang +14 位作者 Li Zhao Sheng Ye Jingdong Song Roujian Lu Hua Zong Changcheng Wu Wei Huang Baoying Huang Yao Deng Ruhan A Wujuan Xie Li Qi Wenbo Xu Hua Ling Wenjie tan 《China CDC weekly》 2022年第38期853-854,共2页
Monkeypox is a zoonotic viral disease caused by the monkeypox virus(MPXV),and historically,all outbreaks have been linked to Africa;however,monkeypox has been posing an alarming challenge to the world in 2022(1)as app... Monkeypox is a zoonotic viral disease caused by the monkeypox virus(MPXV),and historically,all outbreaks have been linked to Africa;however,monkeypox has been posing an alarming challenge to the world in 2022(1)as approximately 60,000 cases have been reported in more than 100 nations and regions worldwide(2).Currently,many cases of monkeypox were identified in many nonendemic countries outside of Central and West Africa,and human-to-human transmission has occurred frequently,especially among men who have sex with men(MSM)presenting new clinical symptoms similar to syphilis and other sexually transmitted infections(3). 展开更多
关键词 CHONGQING CLINICAL OUTSIDE
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Diagnostic value of glypican-3 in serum and liver for primary hepatocellular carcinoma 被引量:57
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作者 Hui Liu Li-Jie Zhang +5 位作者 Peng Li Yun Zhai Yu-Fen tan Ning Li Hui-Guo Ding Chun-Feng Qu 《World Journal of Gastroenterology》 SCIE CAS CSCD 2010年第35期4410-4415,共6页
AIM:To evaluate the diagnostic value of glypican-3(GPC3) in serum and liver for primary hepatocellular carcinoma(HCC).METHODS:Serum levels of GPC3 and α-fetoprotein(AFP) were measured in 75 patients with primary HCC ... AIM:To evaluate the diagnostic value of glypican-3(GPC3) in serum and liver for primary hepatocellular carcinoma(HCC).METHODS:Serum levels of GPC3 and α-fetoprotein(AFP) were measured in 75 patients with primary HCC and 32 patients with liver cirrhosis.Expression of GPC3 and AFP in 58 HCC and 12 cirrhotic specimens was detected with immunohistochemical staining.RESULTS:When the cut-off value of serum GPC3 was set at 300 ng/L,its sensitivity and specificity for HCC were 47.0% and 93.5%,respectively.Among the 14 patients with HCC at stage according to the Barcelona Clinic Liver Cancer staging system,the serum GPC3 level was higher than 300 ng/L in 50%(7/14) patients,the serum AFP level was not ≥ 400 μg/L in any patient.Combined serum AFP and GPC3 significantly increased the sensitivity to the diagnosis of HCC.The GPC3 expression was detected in cytoplasm of HCC cells but not in hepatocytes and bile ducts of benign tumors.Among the 58 HCC patients,the GPC3 was expressed in 100%(28/28) patients with their serum AFP level ≥ 400 μg/L,and in 90%(27/30) patients with their AFP level < 400 μg/L,respectively.The GPC3 was weakly or negatively expressed in all paracarcinomatous and cirrhotic tissue samples.AFP positive HCC cells were only found in 1 out of the 58 HCC patients.CONCLUSION:GPC3 protein is a sensitive and specific serum marker for diagnosis of early HCC.Its expression in liver tissues can be used to discriminate tumor cells from benign hepatic cells. 展开更多
关键词 Hepatocellular carcinoma α-fetoprotein GLYPICAN-3 Diagnosis
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Geomorphologic evidence of phased uplift of the northeastern Qinghai-Tibet Plateau since 14 million years ago 被引量:53
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作者 LU Huayu1, WANG Xiaoyong1, AN Zhisheng1, MIAO Xiaodong1, ZHU Rixiang3, MA Haizhou2, LI Zhen4, tan Hongbing2 & WANG Xianyan1 1. State Key Laboratory of Loess and Quaternary Geology, Institute of Earth Environment, Chinese Academy of Sciences, Xi’an 710075 China 2. Qinghai Institute of Salt Lakes, Chinese Academy of Sciences. Xining 810008, China +1 位作者 3. Institute of Geology and Geophysics, Chinese Academy of Sciences, Beijing 100029, China 4. Department of Geography, Qinghai Normal University, Xining 810008, China 《Science China Earth Sciences》 SCIE EI CAS 2004年第9期822-833,共12页
A typical sequence of fluvial terraces and aeolian deposits overlying these ter- races were multidisciplinary investigated. New evidences for uplift process of the northeastern Qinghai-Tibetan Plateau in the past 14 m... A typical sequence of fluvial terraces and aeolian deposits overlying these ter- races were multidisciplinary investigated. New evidences for uplift process of the northeastern Qinghai-Tibetan Plateau in the past 14 million years were obtained. At least 11 river terraces along Huangshui, the first-class tributary of Yellow River, at the Xining-Huzhu region are identi- fied. While the first one (T1) is classified as an accumulation terrace, the others are all basement river terraces, which consist of the Tertiary sandstone and siltstone bedrock, fluvial gravel and pebbles and the overlying aeolian loess-Red Clay deposit. Samples from the aeolian deposits were examined for paleomagnetic stratigraphic reconstruction (1030 samples), luminescence dating (16 samples), magnetic susceptibility and grain-size distribution (more than 4000 sam- ples). The luminescence dating and stratigraphic correlation suggest that terraces of Tll, T10, T8, T7, T3, T2, T1 were formed at 14, 11.3, 1.55, 1.2, 0.15, 0.07 and 0.01 million years ago, re- spectively. Sedimentological analysis and geomorphological observation indicate that formation and evolution of these terraces were mainly driven by tectonic uplift. Therefore, the terrace se- quence provides an ideal geological record, of the uplift process of the northeastern during the past 14 million years, and the timings of the terraces formation are regarded as the timings of tectonic uplift. The significant uplifting events took place at 14, 11.3, 1.2 and 0.15 mil- lion years ago, respectively. The fluvial incision at the Xining-Huzhu region is less than 100 m during a period of ~12 million years in the Miocene era (between the Tll and T9), while the Huangshui River had incised 432 m during the past 1.2 million years (from T7 to the present floodplain). The river incision process clearly demonstrates that accelerated rising of the north- eastern Qinghai-Tibet Plateau during the late Cenozoic, and provides new evidence of previous thoughts. There was a significant readjustment of the fl 展开更多
关键词 river terrace tectonic uplift loess-Red Clay the past 14 MILLION years northeastern Qinghai-Tibet Plateau.
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基于问题链的中学数学有效教学研究——一项课例研究的启示 被引量:54
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作者 唐恒钧 HAZEL tan +1 位作者 徐元根 张维忠 《数学教育学报》 CSSCI 北大核心 2018年第3期30-34,44,共6页
以问题解决数学观为依据,提出基于问题链的数学教学理念.课例研究中,新手教师与专家教师整体上体现了该理念,通过问题链为学生提供逐渐深入的数学理解和一定的探索空间.在数学主题联结上分别表现出知识关联与方法关联两种类型,并对整个... 以问题解决数学观为依据,提出基于问题链的数学教学理念.课例研究中,新手教师与专家教师整体上体现了该理念,通过问题链为学生提供逐渐深入的数学理解和一定的探索空间.在数学主题联结上分别表现出知识关联与方法关联两种类型,并对整个教学产生影响.问题链教学受到课时的限制较为明显,这需要单元设计等方式加以进一步解决. 展开更多
关键词 数学问题链 有效教学 课例研究
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Mechanism underlying treatment of ischemic stroke using acupuncture:transmission and regulation 被引量:52
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作者 Bing-Qian Cao Feng tan +1 位作者 Jie Zhan Peng-Hui Lai 《Neural Regeneration Research》 SCIE CAS CSCD 2021年第5期944-954,共11页
The inflammatory response after cerebral ischemia/reperfusion is an important cause of neurological damage and repair.After cerebral ischemia/reperfusion,microglia are activated,and a large number of circulating infla... The inflammatory response after cerebral ischemia/reperfusion is an important cause of neurological damage and repair.After cerebral ischemia/reperfusion,microglia are activated,and a large number of circulating inflammatory cells infiltrate the affected area.This leads to the secretion of inflammatory mediators and an inflammatory cascade that eventually causes secondary brain damage,including neuron necrosis,blood-brain barrier destruction,cerebral edema,and an oxidative stress response.Activation of inflammatory signaling pathways plays a key role in the pathological process of ischemic stroke.Increasing evidence suggests that acupuncture can reduce the inflammatory response after cerebral ischemia/reperfusion and promote repair of the injured nervous system.Acupuncture can not only inhibit the activation and infiltration of inflammatory cells,but can also regulate the expression of inflammation-related cytokines,balance the effects of pro-inflammatory and anti-inflammatory factors,and interfere with inflammatory signaling pathways.Therefore,it is important to study the transmission and regulatory mechanism of inflammatory signaling pathways after acupuncture treatment for cerebral ischemia/reperfusion injury to provide a theoretical basis for clinical treatment of this type of injury using acupuncture.Our review summarizes the overall conditions of inflammatory cells,mediators,and pathways after cerebral ischemia/reperfusion,and discusses the possible synergistic intervention of acupuncture in the inflammatory signaling pathway network to provide a foundation to explore the multiple molecular mechanisms by which acupuncture promotes nerve function restoration. 展开更多
关键词 ACUPUNCTURE central nervous system factor inflammation ischemic stroke PATHWAYS protein STROKE
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Effect of electro-acupuncture on substance P, its receptor and corticotropin-releasing hormone in rats with irritable bowel syndrome 被引量:50
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作者 Xiao-Peng Ma Lin-Ying tan Yun Yang Huan-Gan Wu Bin Jiang Hui-Rong Liu Ling Yang 《World Journal of Gastroenterology》 SCIE CAS CSCD 2009年第41期5211-5217,共7页
AIM: To investigate the effect and mechanism of electro-acupuncture lEA) at ST25 and ST37 on irritable bowel syndrome (IBS) of rats. METHODS: A total of 21 male Sprague-Dawley rats were randomly divided into norm... AIM: To investigate the effect and mechanism of electro-acupuncture lEA) at ST25 and ST37 on irritable bowel syndrome (IBS) of rats. METHODS: A total of 21 male Sprague-Dawley rats were randomly divided into normal group, model group and EA group. A rat model of IBS was established by constraining the limbs and distending the colorectum of rats. Rats in EA group received bilateral EA at ST25 and ST37 with a sparse and intense waveform at a frequency of 2/50 Hz for 15 min, once a day for 7 d as a course. Rats in normal and model groups were stimulated by distending colorectum (CR). An abdominal withdrawal reflex (AWR) scoring system was used to evaluate improvements in visceral hypersensitivity. Toluidine blue-improved method, immunohistochemistry and radioimmunoassay were used to observe mucosal mast cells (MC), changes of substance P (SP) and substance P receptor (SPR) in colon and change of corticotropin-releasing hormone (CRH) in hypothalamus. RESULTS: The threshold of visceral sense was significantly lower in model group than in normal group,and significantly higher in EA group than in model group. The number of mucosal MC was greater in model group than in normal group and significantly smaller in EA group than in model group. The CRH level in hypothalamus of rats was significantly higher in model group than in normal group, which was remarkably decreased after electro-acupuncture treatment. The SP and SPR expression in colon of rats in model group was decreased after electro-acupuncture treatment. CONCLUSION: EA at ST25 and ST37 can decrease the number of mucosal MC and down-regulate the expression of CRH in hypothalamus, and the expression of SP and SPR in colon of rats with IBS. 展开更多
关键词 ELECTRO-ACUPUNCTURE Corticotropin-releasing hormone Irritable bowel syndrome Substance P Substance P receptor
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Temporal and regional variations of China's fertilizer consumption by crops during 1998-2008 被引量:50
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作者 XIN Liangjie LI Xiubin tan Minghong 《Journal of Geographical Sciences》 SCIE CSCD 2012年第4期643-652,共10页
The agricultural and land policies in China are always focused on protecting its food supply and security because of the country's large population and improved diets. The crop production guide 'Take Grain as the Ke... The agricultural and land policies in China are always focused on protecting its food supply and security because of the country's large population and improved diets. The crop production guide 'Take Grain as the Key Link prompted peasants to plant grain on most of the agricultural land, leading to the majority of fertilizer being used in grain crops for many years in China. This situation has changed dramatically in recent years. Based on data pertaining to provincial crops sown area and fertilizer use per unit area in 1998 and 2008, the temporal and spatial variations of China's fertilizer consumption by crops were analyzed at the provincial level, and the results are presented here. (1) Fertilizer consumption in China grew strongly in the last decade, while the growth was mainly attributable to the increase of fertilizer consumption by horticultural crops. The fertilizer consumption of grain crops dropped from 71.0% in 1998 to 57.8% in 2008. Thus, it is concluded that the emphasis of fertilizer consumption is shifting toward horticultural crops. (2) There were marked differences in the growth rates of fertilizer consumption from the regional point of view. The national average growth rate of fertilizer consumption was 31.9% during 1998-2008. The western and northeastern parts of the country came close to the national average, while the eastern part was lower, with an average of 13.0%, and central China was much higher (50.8%). The increase of fertilizer consumption in central and west China was higher than the other zones, which already accounted for 77.9% of the national total. Thus, it is concluded that the consumption emphasis of chemical fertilizer shifts toward the central and western regions. (3) The decline of fertilizer consumption by grain crops was largely due to the decrease in sown area compared with the increase by vegetable crops attributable to the enlarging sown area; the increase by orchard crops was affected by both expanding the sown area and fertilizer use per unit are 展开更多
关键词 fertilizer consumption by crops temporal and regional variations China
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Hydrogen Sulfide Alleviates Aluminum Toxicity in Germinating Wheat Seedlings 被引量:49
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作者 Hua Zhang Zhu-Qin tan +3 位作者 Lan-Ying Hu Song-Hua Wang Jian-Ping Luo Russell L. Jones 《Journal of Integrative Plant Biology》 SCIE CAS CSCD 2010年第6期556-567,共12页
Protective role of hydrogen sulfide (H2S) on seed germination and seedling growth was studied in wheat (Triticum) seeds subjected to aluminum (Al3+) stress. We show that germination and seedling growth of wheat... Protective role of hydrogen sulfide (H2S) on seed germination and seedling growth was studied in wheat (Triticum) seeds subjected to aluminum (Al3+) stress. We show that germination and seedling growth of wheat is inhibited by high concentrations of AICI3. At 30 mmol/L AICI3 germination is reduced by about 50% and seedling growth is more dramatically inhibited by this treatment. Pre-incubation of wheat seeds in the H2S donor NaHS alleviates AICI3-induced stress in a dose-dependant manner at an optimal concentration of 0.3 mmol/L. We verified that the role of NaHS in alleviating Al3+ stress could be attributed to H2S/HS- by showing that the level of endogenous H2S increased following NaHS treatment. Furthermore, other sodium salts containing sulfur were ineffective in alleviating Al3+ stress. NaHS pretreatment significantly increased the activities of amylases and esterases and sustained much lower levels of MDA and H2O2 in germinating seeds under Al3+ stress. Moreover, NaHS pretreatment increased the activities of guaiacol peroxidase, ascorbate peroxidase, superoxide dismutase and catalase and decreased that of lipoxygenase. NaHS pretreatment also decreased the uptake of Al3+ in AICI3-treated seed. Taken together these results suggest that H2S could increase antioxidant capability in wheat seeds leading to the alleviation of Al3+ stress. 展开更多
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Combination of Total Astragalus Extract and Total Panax Notoginseng Saponins Strengthened the Protective Effects on Brain Damage through Improving Energy Metabolism and Inhibiting Apoptosis after Cerebral Ischemia-Reperfusion in Mice 被引量:48
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作者 HUANG Xiao-ping tan Hua +1 位作者 CHEN Bei-yang DENG Chang-qing 《Chinese Journal of Integrative Medicine》 SCIE CAS CSCD 2017年第6期445-452,共8页
Objective: To explore the effects and molecular mechanisms of the combination between total Astragalus extract (TAE) and total Panax notoginseng saponins (TPNS) against cerebral ischemia- reperfusion injury. Meth... Objective: To explore the effects and molecular mechanisms of the combination between total Astragalus extract (TAE) and total Panax notoginseng saponins (TPNS) against cerebral ischemia- reperfusion injury. Methods: C57BL/6 mice were randomly divided into sham-operated group, model group, TAE (110 mg/kg) group, TPNS (115 mg/kg) group, TAE-TPNS combination group and Edaravone (4 mg/kg) group, treated for 4 days, then, cerebral ischemia-repeffusion injury was established by bilateral common carotid artery (CCA) ligation for 20 min followed by reperfusion for 1 and 24 h. Results: TPNS could increase adenosine triphosphate (ATP) level, TAE and TAE-TPNS combination increased ATP, adenosine diphosphate (ADP) contents and Na+-K+-ATPase activity, and the effects of TAE-TPNS combination were stronger than those of TAE or TPNS alone after reperfusion for 1 h. After reperfusion for 24 h, TAE, TPNS and TAE-TPNS combination significantly increased neurocyte survival rate and decreased the apoptosis rate as well as down-regulated the expression of phosphorylated c-June N-terminal kinasel/2 (p-JNK1/2), cytochrome C (Cyt C), cysteine aspartic acid-specific protease (Caspase)-9 and Caspase-3. Furthermore, the effects in TAE-TPNS combination were better than those in TAE or TPNS alone. Conclusion: The combination of TAE 110 mg/kg and TPNS 115 mg/kg could strengthen protective effects on cerebral ischemia injury, the mechanism underlying might be related to improving jointly the early energy metabolism, and relieving the delayed apoptosis via inhibiting the mitochondrial apoptosis pathway of JNK signal transduction. 展开更多
关键词 total Astragalus extract total Panax notoginseng saponins COMBINATION cerebral ischemia- reperfusion energy metabolism C-Jun N-terminal kinase signal transduction mitochondrial apoptosis pathway Chinese medicine
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International expert consensus on laparoscopic pancreaticoduodenectomy 被引量:48
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作者 Renyi Qin Michael L.Kendrick +25 位作者 Christopher L.Wolfgang Barish H.Edil Chinnusamy Palanivelu Rowan WParks Yinmo Yang Jin He Taiping Zhang Yiping Mou Xianjun Yu Bing Peng Palanisamy Senthilnathan Ho-Seong Han Jae Hoon Lee Michiaki Unno Steven WMOlde Damink Virinder Kumar Bansal Pierce Chow tan To Cheung Nim Choi Yu-Wen Tien Chengfeng Wang Manson Fok Xiujun Cai Shengquan Zou Shuyou Peng Yupei Zhao 《Hepatobiliary Surgery and Nutrition》 SCIE 2020年第4期464-483,共20页
Importance:While laparoscopic pancreaticoduodenectomy(LPD)is being adopted with increasing enthusiasm worldwide,it is still challenging for both technical and anatomical reasons.Currently,there is no consensus on the ... Importance:While laparoscopic pancreaticoduodenectomy(LPD)is being adopted with increasing enthusiasm worldwide,it is still challenging for both technical and anatomical reasons.Currently,there is no consensus on the technical standards for LPD.Objective:The aim of this consensus statement is to guide the continued safe progression and adoption of LPD.Evidence Review:An international panel of experts was selected based on their clinical and scientific expertise in laparoscopic and open pancreaticoduodenectomy.Statements were produced upon reviewing the literature and assessed by the members of the expert panel.The literature search and its critical appraisal were limited to articles published in English during the period from 1994 to 2019.The Web of Science,Medline,and Cochrane Library and Clinical Trials databases were searched,The search strategy included,but was not limited to,the terms'laparoscopic','pancreaticoduodenectomy,'pancreatoduodenectomy','Whipple's operation',and'minimally invasive surgery'.Reference lists from the included articles were manually checked for any additional studies,which were included when appropriate.Delphi method was used to establish expert consensus and the AGREE II-GRS Instrument was applied to assess the methodological quality and externally validate the final statements.The statements were further discussed during a one-day face-to-face meeting at the 1st Summit on Minimally Invasive Pancreatico-Biliary Surgery in Wuhan,China.Findings:Twenty-eight international experts from 8 countries constructed the expert panel.Sixteen statements were produced by the members of the expert panel.At least 80%of responders agreed with the majority(80%)of statements.Other than three randomized controlled trials published to date,most evidences were based on level 3 or 4 studies according to the AGREE II-GRS Instrument.Conclusions and Relevance:The Wuhan international expert consensus meeting on LPD has produced a set of clinical practice statements for the safe development and progression of LP 展开更多
关键词 CONSENSUS PANCREATICODUODENECTOMY LAPAROSCOPY Delphi technique
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