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Cancer statistics in China and United States,2022:profiles,trends,and determinants 被引量:1330
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作者 Changfa Xia Xuesi dong +8 位作者 He Li Maomao Cao Dianqin Sun Siyi He Fan Yang Xinxin Yan Shaoli Zhang Ni Li Wanqing Chen 《Chinese Medical Journal》 SCIE CAS CSCD 2022年第5期584-590,共7页
Background:The cancer burden in the United States of America(USA)has decreased gradually.However,China is experiencing a transition in its cancer profiles,with greater incidence of cancers that were previously more co... Background:The cancer burden in the United States of America(USA)has decreased gradually.However,China is experiencing a transition in its cancer profiles,with greater incidence of cancers that were previously more common in the USA.This study compared the latest cancer profiles,trends,and determinants between China and USA.Methods:This was a comparative study using open-source data.Cancer cases and deaths in 2022 were calculated using cancer estimates from GLOBOCAN 2020 and population estimates from the United Nations.Trends in cancer incidence and mortality rates in the USA used data from the Surveillance,Epidemiology,and End Results program and National Center for Health Statistics.Chinese data were obtained from cancer registry reports.Data from the Global Burden of Disease 2019 and a decomposition method were used to express cancer deaths as the product of four determinant factors.Results:In 2022,there will be approximately 4,820,000 and 2,370,000 new cancer cases,and 3,210,000 and 640,000 cancer deaths in China and the USA,respectively.The most common cancers are lung cancer in China and breast cancer in the USA,and lung cancer is the leading cause of cancer death in both.Age-standardized incidence and mortality rates for lung cancer and colorectal cancer in the USA have decreased significantly recently,but rates of liver cancer have increased slightly.Rates of stomach,liver,and esophageal cancer decreased gradually in China,but rates have increased for colorectal cancer in the whole population,prostate cancer in men,and other seven cancer types in women.Increases in adult population size and population aging were major determinants for incremental cancer deaths,and case-fatality rates contributed to reduced cancer deaths in both countries.Conclusions:The decreasing cancer burden in liver,stomach,and esophagus,and increasing burden in lung,colorectum,breast,and prostate,mean that cancer profiles in China and the USA are converging.Population aging is a growing determinant of incremental cancer burden.Progre 展开更多
关键词 CANCER INCIDENCE MORTALITY TRENDS AGING China USA
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A Robust CRISPR/Cas9 System for Convenient, High-Efficiency Multiplex Genome Editing in Monocot and Dicot Plants 被引量:331
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作者 Xingliang Ma Qunyu Zhang +17 位作者 Qinlong Zhu Wei Liu Yan Chen Rong Qiu Bin Wang Zhongfang Yang Heying Li Yuru Lin Yongyao Xie Rongxin Shen Shuifu Chen Zhi Wang Yuanling Chen Jingxin Guo Letian Chen Xiucai Zhao Zhicheng dong Yao-Guang Liu 《Molecular Plant》 SCIE CAS CSCD 2015年第8期1274-1284,共11页
CRISPR/Cas9 genome targeting systems have been applied to a variety of species. However, most CRISPR/Cas9 systems reported for plants can only modify one or a few target sites. Here, we report a robust CRISPR/Cas9 vec... CRISPR/Cas9 genome targeting systems have been applied to a variety of species. However, most CRISPR/Cas9 systems reported for plants can only modify one or a few target sites. Here, we report a robust CRISPR/Cas9 vector system, utilizing a plant codon optimized Cas9 gene, for convenient and high- efficiency multiplex genome editing in monocot and dicot plants. We designed PCR-based procedures to rapidly generate multiple sgRNA expression cassettes, which can be assembled into the binary CRISPR/ Cas9 vectors in one round of cloning by Golden Gate ligation or Gibson Assembly. With this system, we edi- ted 46 target sites in rice with an average 85.4% rate of mutation, mostly in biallelic and homozygous status. We reasoned that about 16% of the homozygous mutations in rice were generated through the non-homol- ogous end-joining mechanism followed by homologous recombination-based repair. We also obtained uni- form biallelic, heterozygous, homozygous, and chimeric mutations in Arabidopsis T1 plants. The targeted mutations in both rice and Arabidopsis were heritable. We provide examples of loss-of-function gene mu- tations in To rice and T1Arabidopsis plants by simultaneous targeting of multiple (up to eight) members of a gene family, multiple genes in a biosynthetic pathway, or multiple sites in a single gene. This system has provided a versatile toolbox for studying functions of multiple genes and gene families in plants for basic research and genetic improvement. 展开更多
关键词 sequence-specific nucleases genome editing CRISPR/Cas9 rice Arabidopsis
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China Stroke Statistics 2019:A Report From the National Center for Healthcare Quality Management in Neurological Diseases,China National Clinical Research Center for Neurological Diseases,the Chinese Stroke Association,National Center for Chronic and Non-communicable Disease Control and Prevention,Chinese Center for Disease Control and Prevention and Institute for Global Neuroscience and Stroke Collaborations 被引量:227
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作者 Yong-Jun Wang Zi-Xiao Li +16 位作者 Hong-Qiu Gu Yi Zhai Yong Jiang Xing-Quan Zhao Yi-Long Wang Xin Yang Chun-Juan Wang Xia Meng Hao Li Li-Ping Liu Jing Jing Jing Wu An-Ding Xu Qiang dong David Wang Ji-Zong Zhao On behalf of China Stroke Statistics 2019 Writing Committee 《Stroke & Vascular Neurology》 SCIE 2020年第3期211-239,共29页
China faces the greatest challenge from stroke in the world.The death rate for cerebrovascular diseases in China was 149.49 per 100000,accounting for 1.57 million deaths in 2018.It ranked third among the leading cause... China faces the greatest challenge from stroke in the world.The death rate for cerebrovascular diseases in China was 149.49 per 100000,accounting for 1.57 million deaths in 2018.It ranked third among the leading causes of death behind malignant tumours and heart disease.The age-standardised prevalence and incidence of stroke in 2013 were 1114.8 per 100000 population and 246.8 per 100000 person-years,respectively.According to the Global Burden of Disease Study 2017,the years of life lost(YLLs)per 100000 population for stroke increased by 14.6%;YLLs due to stroke rose from third highest among all causes in 1990 to the highest in 2017.The absolute numbers and rates per 100000 population for all-age disability-adjusted life years(DALYs)for stroke increased substantially between 1990 and 2017,and stroke was the leading cause of all-age DALYs in 2017.The main contributors to cerebrovascular diseases include behavioural risk factors(smoking and alcohol use)and pre-existing conditions(hypertension,diabetes mellitus,dyslipidaemia and atrial fibrillation(AF)).The most prevalent risk factors among stroke survivors were hypertension(63.0%-84.2%)and smoking(31.7%-47.6%).The least prevalent was AF(2.7%-7.4%).The prevalences for major risk factors for stroke are high and most have increased over time.Based on the latest national epidemiological data,26.6%of adults aged≥15 years(307.6 million adults)smoked tobacco products.For those aged≥18 years,age-adjusted prevalence of hypertension was 25.2%;adjusted prevalence of hypercholesterolaemia was 5.8%;and the standardised prevalence of diabetes was 10.9%.For those aged≥40 years,the standardised prevalence of AF was 2.31%.Data from the Hospital Quality Monitoring System showed that 3010204 inpatients with stroke were admitted to 1853 tertiary care hospitals during 2018.Of those,2466785(81.9%)were ischaemic strokes(ISs);447609(14.9%)were intracerebral haemorrhages(ICHs);and 95810(3.2%)were subarachnoid haemorrhages(SAHs).The average age of patients admitted was 66 years old,and 展开更多
关键词 admitted smoke insurance
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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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Tectonics of South China Continent and its implications 被引量:139
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作者 ZHANG GuoWei GUO AnLin +7 位作者 WANG YueJun LI SanZhong dong YunPeng LIU ShaoFeng HE DengFa CHENG ShunYou LU RuKui YAO AnPing 《Science China Earth Sciences》 SCIE EI CAS 2013年第11期1804-1828,共25页
This paper aims at exploring the tectonic characteristics of the South China Continent (SCC) and extracting the universal tec- tonic rules from these characteristics,to help enrich the plate tectonic theory and bett... This paper aims at exploring the tectonic characteristics of the South China Continent (SCC) and extracting the universal tec- tonic rules from these characteristics,to help enrich the plate tectonic theory and better understand the continental dynamic system. For this purpose, here we conduct a multi-disciplinary investigation and combine it with the previous studies to reas- sess the tectonics and evolution of SCC and propose that the tectonic framework of the continent comprises two blocks, three types of tectonic units, four deformation systems, and four evolutionary stages with distinctive mechanism and tectonic characteris- tics since the Neoproterozoic. The four evolutionary stages are: (1) The amalgamation and break-up of the Neoproterozoic plates, typically the intracontinental rifting. (2) The early Paleozoic and Mesozoic intracontinental orogeny confined by plate tectonics, forming two composite tectonic domains. (3) The parallel operation of the Yangtze cratonization and intracontinental orogeny, and multi-phase reactivation of the Yangtze craton. (4) The association and differentiation evolution of plate tectonics and intraconti- nental tectonics, and the dynamic characteristics under the Meso-Cenozoic modem global plate tectonic regime. 展开更多
关键词 tectonics of South China Continent intracontinental orogeny medium- and small-sized plate tectonics continental dynamics
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关于广域测量系统及广域控制保护系统的评述 被引量:109
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作者 薛禹胜 徐伟 +1 位作者 Zhaoyang dong 万秋兰 《电力系统自动化》 EI CSCD 北大核心 2007年第15期1-5,16,共6页
评述广域测量系统及广域控制保护系统的构成、关键技术及应用领域,提出广域测量预警控制系统的概念。分别讨论了基于纯相量测量单元(PMU)数据的应用功能,以及结合PMU数据与模型仿真结果的应用功能。在此基础上指出广域测量预警控制系统... 评述广域测量系统及广域控制保护系统的构成、关键技术及应用领域,提出广域测量预警控制系统的概念。分别讨论了基于纯相量测量单元(PMU)数据的应用功能,以及结合PMU数据与模型仿真结果的应用功能。在此基础上指出广域测量预警控制系统理论和应用的瓶颈及可能的解决途径。 展开更多
关键词 广域测量系统 广域控制保护系统 相量测量单元 数据挖掘
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Identification of a novel coronavirus causing severe pneumonia in human:a descriptive study 被引量:111
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作者 Li-Li Ren Ye-Ming Wang +33 位作者 Zhi-Qiang Wu Zi-Chun Xiang Li Guo Teng Xu Yong-Zhong Jiang Yan Xiong Yong-Jun Li Xing-Wang Li Hui Li Guo-Hui Fan Xiao-Ying Gu Yan Xiao Hong Gao Jiu-Yang Xu Fan Yang Xin-Ming Wang Chao Wu Lan Chen Yi-Wei Liu Bo Liu Jian Yang Xiao-Rui Wang Jie dong Li Li Chao-Lin Huang Jian-Ping Zhao Yi Hu Zhen-Shun Cheng Un-Lin Liu Zhao-Hui Qian Chuan Qin Qi Jin Bin Cao Jian-Wei Wang 《Chinese Medical Journal》 SCIE CAS CSCD 2020年第9期1015-1024,共10页
Background:Human infections with zoonotic coronaviruses(CoVs),including severe acute respiratory syndrome(SARS)-CoV and Middle East respiratory syndrome(MERS)-CoV,have raised great public health concern globally.Here,... Background:Human infections with zoonotic coronaviruses(CoVs),including severe acute respiratory syndrome(SARS)-CoV and Middle East respiratory syndrome(MERS)-CoV,have raised great public health concern globally.Here,we report a novel batorigin CoV causing severe and fatal pneumonia in humans.Methods:We collected clinical data and bronchoalveolar lavage(BAL)specimens from five patients with severe pneumonia from Wuhan Jinyintan Hospital,Hubei province,China.Nucleic acids of the BAL were extracted and subjected to next-generation sequencing.Virus isolation was carried out,and maximum-likelihood phylogenetic trees were constructed.Results:Five patients hospitalized from December 18 to December 29,2019 presented with fever,cough,and dyspnea accompanied by complications of acute respiratory distress syndrome.Chest radiography revealed diffuse opacities and consolidation.One of these patients died.Sequence results revealed the presence of a previously unknownβ-CoV strain in all five patients,with 99.8%to 99.9%nucleotide identities among the isolates.These isolates showed 79.0%nucleotide identity with the sequence of SARS-CoV(GenBank NC_004718)and 51.8%identity with the sequence of MERS-CoV(GenBank NC_019843).The virus is phylogenetically closest to a bat SARS-like CoV(SL-ZC45,GenBank MG772933)with 87.6%to 87.7%nucleotide identity,but is in a separate clade.Moreover,these viruses have a single intact open reading frame gene 8,as a further indicator of bat-origin CoVs.However,the amino acid sequence of the tentative receptor-binding domain resembles that of SARS-CoV,indicating that these viruses might use the same receptor.Conclusion:A novel bat-borne CoV was identified that is associated with severe and fatal respiratory disease in humans. 展开更多
关键词 Bat-origin CORONAVIRUS Zoonotic transmission PNEUMONIA ETIOLOGY Next-generation sequencing
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Artificial intelligence in healthcare:past,present and future 被引量:99
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作者 Fei Jiang Yong Jiang +7 位作者 Hui Zhi Yi dong Hao Li Sufeng Ma Yilong Wang Qiang dong Haipeng Shen Yongjun Wang 《Stroke & Vascular Neurology》 SCIE 2017年第4期230-243,共14页
Artificial intelligence(AI)aims to mimic human cognitive functions.It is bringing a paradigm shift to healthcare,powered by increasing availability of healthcare data and rapid progress of analytics techniques.We surv... Artificial intelligence(AI)aims to mimic human cognitive functions.It is bringing a paradigm shift to healthcare,powered by increasing availability of healthcare data and rapid progress of analytics techniques.We survey the current status of AI applications in healthcare and discuss its future.AI can be applied to various types of healthcare data(structured and unstructured).Popular AI techniques include machine learning methods for structured data,such as the classical support vector machine and neural network,and the modern deep learning,as well as natural language processing for unstructured data.Major disease areas that use AI tools include cancer,neurology and cardiology.We then review in more details the AI applications in stroke,in the three major areas of early detection and diagnosis,treatment,as well as outcome prediction and prognosis evaluation.We conclude with discussion about pioneer AI systems,such as IBM Watson,and hurdles for real-life deployment of AI. 展开更多
关键词 DIAGNOSIS bringing POPULAR
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Practice guidelines for the pathological diagnosis of primary liver cancer: 2015 update 被引量:100
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作者 Wen-Ming Cong Hong Bu +5 位作者 Jie Chen Hui dong Yu-Yao Zhu Long-Hai Feng Jun Chen 《World Journal of Gastroenterology》 SCIE CAS 2016年第42期9279-9287,共9页
In 2010, a panel of Chinese pathologists reported the first expert consensus for the pathological diagnosis of primary liver cancers to address the many contradictions and inconsistencies in the pathological character... In 2010, a panel of Chinese pathologists reported the first expert consensus for the pathological diagnosis of primary liver cancers to address the many contradictions and inconsistencies in the pathological characteristics and diagnostic criteria for PLC. Since then considerable clinicopathological studies have been conducted globally, prompting us to update the practice guidelines for the pathological diagnosis of PLC. In April 18, 2014, a Guideline Committee consisting of 40 specialists from seven Chinese Societies(including Chinese Society of Liver Cancer, Chinese Anti-Cancer Association; Liver Cancer Study Group, Chinese Society of Hepatology, Chinese Medical Association; Chinese Society of Pathology, Chinese Anti-Cancer Association; Digestive Disease Group, Chinese Society of Pathology, Chinese Medical Association; Chinese Society of Surgery, Chinese Medical Association; Chinese Society of Clinical Oncology, Chinese Anti-Cancer Association; Pathological Group of Hepatobiliary Tumor and Liver Transplantation, Chinese Society of Pathology, Chinese Medical Association) was created for the formulation of the first guidelines for the standardization of the pathological diagnosis of PLC, mainly focusing on the following topics: gross specimen sampling, concepts and diagnostic criteria of small hepatocellular carcinoma(SHCC), microvascular invasion(MVI), satellite nodules,and immunohistochemical and molecular diagnosis. The present updated guidelines are reflective of current clinicopathological studies, and include a novel 7-point baseline sampling protocol, which stipulate that at least four tissue specimens should be sampled at the junction of the tumor and adjacent liver tissues in a 1:1 ratio at the 12, 3, 6 and 9 o'clock reference positions. For the purposes of molecular pathological examination, at least one specimen should be sampled at the intratumoral zone, but more specimens should be sampled for tumors harboring different textures or colors. Specimens should be sampled at both adjacent and distant peri 展开更多
关键词 Liver cancer Hepatocellular carcinoma Intrahepatic cholangiocarcinoma Practice guidelines PATHOLOGY DIAGNOSIS
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A review on the eco-geography of soil fauna in China 被引量:94
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作者 YIN Xiuqin SONG Bo +2 位作者 dong Weihua XIN Weidong WANG Yeqiao 《Journal of Geographical Sciences》 SCIE CSCD 2010年第3期333-346,共14页
This review summarizes main research findings in soil fauna eco-geography in China in the past 30 years. The subject areas and main results were overviewed including biodiversity and eco-geological distribution of soi... This review summarizes main research findings in soil fauna eco-geography in China in the past 30 years. The subject areas and main results were overviewed including biodiversity and eco-geological distribution of soil fauna communities. Studies of ecological distributions of soil fauna and dynamic ranges in space from tropical, subtropical to temperate regions, and in categories from forest, grassland, desert, wetland, farmland to urban ecosystems, the responses and indications of soil fauna to soil environments. Effects of intensive disturbance such as fire, grazing, farming, fertilization on soil fauna include sensitive (e.g. nematode) and rare groups and community indexes. The functions of soil fauna were discussed including environmental construction, environmental purification, litter decomposition and elements cycling. Interactions between soil fauna and other biota in soil ecosystems and linking between aboveground and belowground diversity and the effects of global change on soil fauna community in China were also included. Finally, the authors pointed out common interests in soil fauna eco-geographical studies, which include application of molecule biology into soil fauna taxa; function and mechanism of soil fauna community diversity; interaction between aboveground and belowground ecosystems; effects of disturbance, pollution, biological invasion, and global change on soil fauna community and function. The review is to provide a scientific basis for promoting soil fauna eco-geographical studies in China. 展开更多
关键词 soil fauna BIODIVERSITY BIO-INDICATORS functional role eco-geography
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Quantitative analysis of vascular endothelial growth factor, microvascular density and their clinicopathologic features in human hepatocellular carcinoma 被引量:81
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作者 Deng-Fu Yao, Xin-Hua Wu, Yong Zhu, Gong-Sheng Shi, Zhi-Zhen dong, Deng-Bing Yao, Wei Wu, Li-Wei Qiu and Xian-Yong Meng Nantong, China Research Center of Clinical Molecular Biology , Department of Pathology and Department of Gastroenterology , Affiliated Hos- pital of Nantong University Department of Diagnostics , and Institute of Neurosciences , Nantong University Nantong 226001, China 《Hepatobiliary & Pancreatic Diseases International》 SCIE CAS 2005年第2期220-226,共7页
BACKGROUND: Angiogenesis is known to be essential to the survival, growth, invasion, and metastasis of tumor cells. Vascular endothelial growth factor (VEGF) are an important angiogenic factor regulating tumor angioge... BACKGROUND: Angiogenesis is known to be essential to the survival, growth, invasion, and metastasis of tumor cells. Vascular endothelial growth factor (VEGF) are an important angiogenic factor regulating tumor angiogenesis, but its significance and tumor pathologic features are un- clear in hepatocellular carcinoma (HCC). In the present study, we analyzed expression of tissue VEGF, alteration of microvascular density (MVD) in microvessel angiogenesis, development and metastasis of HCC, and level of serum VEGF in differential diagnosis of benign and malignant liv- er diseases. METHODS: Tumor specimens were prospectively collected from HCC patients undergoing resection. Total RNAs were extracted and the expression levels were detected from different parts of HCC tissues. The cellular distributions of VEGF and MVD of liver tumors and their paracancerous and distal cancerous tissues were investigated by streptavi- din peroxidase (S-P) immunohistochemistry, respectively. The VEGF levels of circulating blood and hepatoma tissues were measured by enzyme-linked immunosorbent assay. RESULTS: The incidence of VEGF expression was 63.9% in HCCs (23/36 cases), 78.3% in non-encapsulated HCCs (18/23), and 90.9% in HCCs with extrahepatic metastasis (10/11), respectively. The VEGF expression was tightly correlated with MVD (P <0.01). The MVD in HCC with metastasis, low differentiation or non-encapsulation was significantly higher than that in HCC with intact capsule, high differentiation, or no metastasis. No significant diffe- rence was found between VEGF, MVD, tumor size, and hepatitis virus infection. The level of total RNA in HCC tis- sues was significantly lower but the VEGF level significantly higher than those in paracancerous or distal cancerous ones (P<0.01). The abnormal expression levels of VEGF in sera of HCC patients were directly correlated with the me- tastasis and recurrence of tumors. CONCLUSION: The high expression of VEGF and abnor- mality of tissue MVD are useful predictors for vascular inva- sion and metastas 展开更多
关键词 vascular endothelial growth factor hepatocellular carcinoma ELISA microvascular density immunohistochemistry
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Third generation of vortex identification methods:Omega and Liutex/Rortex based systems 被引量:91
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作者 Chaoqun Liu Yi-sheng Gao +5 位作者 Xiang-rui dong Yi-qian Wang Jian-ming Liu Yu-ning Zhang Xiao-shu Cai Nan Gui 《Journal of Hydrodynamics》 SCIE EI CSCD 2019年第2期205-223,共19页
A vortex is intuitively recognized as the rotational/swirling motion of fluids,but a rigorous and universally-accepted definition is still not available.Vorticity tube/filament has been regarded equivalent to a vortex... A vortex is intuitively recognized as the rotational/swirling motion of fluids,but a rigorous and universally-accepted definition is still not available.Vorticity tube/filament has been regarded equivalent to a vortex since Helmholtz proposed the concepts of vorticity tube/filament in 1858 and the vorticity-based methods can be categorized as the first generation of vortex identification methods.During the last three decades,a lot of vortex identification methods,including 0,A,and Aci criteria,have been proposed to overcome the problems associated with the vorticity-based methods.Most of these criteria are based on the Cauchy-Stokes decomposition and/or eigenvalues of the velocity gradient tensor and can be considered as the second generation of vortex identification methods.Starting from 2014,the Vortex and Turbulence Research Team at the University of Texas at Arlington(the UTA team)focus on the development of a new generation of vortex identification methods.The first fruit of this effort,a new Omega(/2)vortex identification method,which defined a vortex as a connected region where the vorticity overtakes the deformation,was published in 2016.In 2017 and 2018,a Liutex(previously called Rortex)vector was proposed to provide a mathematical definition of the local rigid rotation part of the fluid motion,including both the local rotational axis and the rotational strength.Liutex/Rortex is a new physical quantity with scalar,vector and tensor forms exactly representing the local rigid rotation of fluids.Meanwhile,a decomposition of the vorticity to a rotational part namely Liutex/Rortex and an anti-symmetric shear part(RS decomposition)was introduced in 2018,and a universal decomposition of the velocity gradient tensor to a rotation part(7?)and a non-rotation part(NR、was also given in 2018 as a counterpart of the traditional Cauchy-Stokes decomposition.Later in early 2019,a Liutex/Rortex based Omega method called Omega-Liutex,which combines the respective advantages of both Liutex/Rortex and Omega methods,was dev 展开更多
关键词 VORTEX DEFINITION VORTEX identification OMEGA Liutex/Rortex direct NUMERICAL simulation TURBULENCE
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Fluid therapy for severe acute pancreatitis in acute response stage 被引量:91
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作者 MAO En-qiang TANG Yao-qing FEI Jian QIN Shuai WU Jun LI Lei MIN dong ZHANG Sheng-dao 《Chinese Medical Journal》 SCIE CAS CSCD 2009年第2期169-173,共5页
Background Fluid therapy for severe acute pancreatitis (SAP) should not only resolve deficiency of blood volume, but also prevent fluid sequestration in acute response stage. Up to date, there has not a strategy for... Background Fluid therapy for severe acute pancreatitis (SAP) should not only resolve deficiency of blood volume, but also prevent fluid sequestration in acute response stage. Up to date, there has not a strategy for fluid therapy dedicated to SAP. So, this study was aimed to investigate the effects of fluid therapy treatment on prognosis of SAP. Methods Seventy-six patients were admitted prospectively according to the criteria within 72 hours of SAP onset. They were randomly assigned to a rapid fluid expansion group (Group I, n=36) and a controlled fluid expansion group (Group II n=-40). Hemodynamic disorders were either quickly (fluid infusion rate was 10-15 ml.kg-1-h-1, Group I) or gradually improved (fluid infusion rate was 5-10 ml-kg1.h-1, Group II) through controlling the rate of fluid infusion. Parameters of fluid expansion, blood lactate concentration were obtained when meeting the criteria for fluid expansion. And APACHE II scores were obtained serially for 72 hours. Rate of mechanical ventilation, incidence of abdominal compartment syndrome (ACS), sepsis, and survival rate were obtained. Results The two groups had statistically different (P 〈0.05) time intervals to meet fluid expansion criteria (Group I, 13.5±6.6 hours; Group II, (24.0±5.4) hours). Blood lactate concentrations were both remarkably lower as compared to the level upon admission (P 〈0.05) and reached the normal level in both groups upon treatment. It was only at day 1 that hematocrit was significantly lower in Group I (35.6%±6.8%) than in Group II (38.5%±5.4%) (P〈0.01). Amount of crystalloid and colloid in group I ((4028±1980)ml and (1336±816)ml) on admission day was more than those of group II ((2472±1871)ml and (970±633)ml). No significant difference was found in the total amount of fluids within four days of admission between the two groups (P〉0.05). Total amount of fluid sequestration within 4 days was higher in Group I ((5378±2751)ml� 展开更多
关键词 pancreatitis acute necrotizing RESUSCITATION acute response stage
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关于低频振荡分析方法的评述 被引量:82
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作者 薛禹胜 郝思鹏 +2 位作者 刘俊勇 Zhaoyang dong Gerard LEDWICH 《电力系统自动化》 EI CSCD 北大核心 2009年第3期1-8,共8页
为更好地梳理概念,将低频振荡分析方法分为两大类,即针对系统模型平衡点的特征根方法以及沿着系统受扰轨迹的模式提取方法。平衡点特征根方法可进一步按采用的系统模型分为确定性的线性化模型、确定性的非线性模型和概率模型。这类方法... 为更好地梳理概念,将低频振荡分析方法分为两大类,即针对系统模型平衡点的特征根方法以及沿着系统受扰轨迹的模式提取方法。平衡点特征根方法可进一步按采用的系统模型分为确定性的线性化模型、确定性的非线性模型和概率模型。这类方法与具体扰动无关,但只能反映系统在该平衡点附近的动态行为,故不适用于包含强非线性、变系数、相继故障或有离散控制的系统。受扰轨迹模式分析方法则从特定扰动下的时间响应曲线中提取振荡信息的时间序列,包括系统模型未知情况下(如实测轨迹)的信号处理法和系统模型已知情况下(如仿真轨迹)的分时段定常线性化法。在评述各种方法的基础上,提出改进的思路及有望突破的研究方向。 展开更多
关键词 低频振荡 平衡点特征根 轨迹特征根时间序列 信号处理 保稳降维线性变换 分时段定常线性化
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关于暂态稳定不确定性分析的评述 被引量:77
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作者 薛禹胜 刘强 +2 位作者 Zhaoyang dong Gerard LEDWICH 袁越 《电力系统自动化》 EI CSCD 北大核心 2007年第14期1-6,75,共7页
从随机变量、概率模型、概率算法以及特定场景下的暂态稳定评估等方面,回顾国内外对暂态稳定概率分析和风险分析的研究和现状,归纳各种分析方法的原理及优缺点,讨论减少计算量的技术,探讨暂态稳定性概率分析及风险分析的发展方向。指出... 从随机变量、概率模型、概率算法以及特定场景下的暂态稳定评估等方面,回顾国内外对暂态稳定概率分析和风险分析的研究和现状,归纳各种分析方法的原理及优缺点,讨论减少计算量的技术,探讨暂态稳定性概率分析及风险分析的发展方向。指出在计算失稳概率时尽量采用灵敏度分析技术来代替抽样仿真,将大大减少计算量。提出用最优稳定控制的代价来反映经济损失,即用主动停电造成的损失代替系统失稳后不受控停电的损失,使风险值可以实际计算。 展开更多
关键词 暂态稳定 概率分析 风险评估 条件概率 蒙特卡罗仿真
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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:81
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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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Clinical characteristics, diagnosis and management of respiratory distress syndrome in full-term neonates 被引量:79
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作者 LIU Jing SHI Yun dong Jian-ying ZHENG Tian LI Jing-ya LU Li-li LIU Jing-jing LIANG Jing ZHANG Hao FENG Zhi-chun 《Chinese Medical Journal》 SCIE CAS CSCD 2010年第19期2640-2644,共5页
Background Respiratory distress syndrome (RDS) is one of the most common causes of neonatal respiratory failure and neonatal death, however, its clinical characteristics are very different from premature RDS, and th... Background Respiratory distress syndrome (RDS) is one of the most common causes of neonatal respiratory failure and neonatal death, however, its clinical characteristics are very different from premature RDS, and these characteristics have not been well documented as yet. This study was to investigate the pathogenesis, clinical characteristics and management strategies of RDS in full-term neonates, with the aim of developing a working protocol for improving the outcome in full-term neonates with RDS. Methods A total of 125 full-term infants with RDS were enrolled in this study. Their clinical and laboratory data were collected for analyzing the characteristics of full-term neonatal RDS. Results (1) The 125 cases included 94 male and 31 female infants, vaginal delivery occurred in 80 cases and cesarean section in 45 cases. (2) The onset time of RDS was (3.11±3.59) hours after birth. (3)The possible reasons included severe perinatal infections in 63 patients, elective cesarean section in 34 cases, severe birth asphyxia in 12 patients, meconium aspiration syndrome in 9 patients, pulmonary hemorrhage in 4 patients and maternal diabetes in 3 patients. (4) Complications included multiple organ system failure (MOSF) in 49 patients, persistent pulmonary hypertension of newborn (PPHN) in 25 patients, acute renal failure in 18 patients, severe hyperkalemia in 25 patients, severe metabolic acidosis in 6 cases, severe myocardial injury in 9 cases, pulmonary hemorrhage in 3 cases, disseminated intravascular coagulation in 14 patients and shock in 12 patients.(5) Four patients died, the mortality was therefore 3.2% with the main cause of septicemia complicating of MOSF, but their prognosis was improved while comprehensive treatment measures including early mechanical ventilation and broad spectrum antibiotics were taken into account. Conclusions RDS is not an uncommon disease in full-term infants and is associated with a higher mortality, its clinical characteristics are very different from 展开更多
关键词 respiratory distress syndrome clinical characteristics diagnostic criteria management strategies NEWBORN FULL-TERM
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Contribution of phenylpropanoid metabolism to plant development and plant–environment interactions 被引量:75
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作者 Nai-Qian dong Hong-Xuan Lin 《Journal of Integrative Plant Biology》 SCIE CAS CSCD 2021年第1期180-209,共30页
Phenylpropanoid metabolism is one of the most important metabolisms in plants, yielding more than 8,000 metabolites contributing to plant development and plant-environment interplay.Phenylpropanoid metabolism material... Phenylpropanoid metabolism is one of the most important metabolisms in plants, yielding more than 8,000 metabolites contributing to plant development and plant-environment interplay.Phenylpropanoid metabolism materialized during the evolution of early freshwater algae that were initiating terrestrialization and land plants have evolved multiple branches of this pathway, which give rise to metabolites including lignin, flavonoids, lignans, phenylpropanoid esters, hydroxycinnamic acid amides, and sporopollenin.Recent studies have revealed that many factors participate in the regulation of phenylpropanoid metabolism, and modulate phenylpropanoid homeostasis when plants undergo successive developmental processes and are subjected to stressful environments. In this review, we summarize recent progress on elucidating the contribution of phenylpropanoid metabolism to the coordination of plant development and plant–environment interaction, and metabolic flux redirection among diverse metabolic routes. In addition, our review focuses on the regulation of phenylpropanoid metabolism at the transcriptional, post-transcriptional, post-translational,and epigenetic levels, and in response to phytohormones and biotic and abiotic stresses. 展开更多
关键词 FLAVONOIDS LIGNIN metabolic flux PHENYLPROPANOID secondary metabolites
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A Rare Allele of GS2 Enhances Grain Size anc Grain Yield in Rice 被引量:73
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作者 Jiang Hu Yuexing Wang +16 位作者 Yunxia Fang Longjun Zeng Jie Xu Haiping Yu Zhenyuan Shi Jiangjie Pan dong Zhang Shujing Kang Li Zhu Guojun dong Longbiao Guo Dali Zeng Guangheng Zhang Lihong Xie Guosheng Xiong Jiayang Li Qian Qian 《Molecular Plant》 SCIE CAS CSCD 2015年第10期1455-1465,共11页
Grain size determines grain weight and affects grain quality. Several major quantitative trait loci (QTLs) regulating grain size have been cloned; however, our understanding of the underlying mechanism that regulate... Grain size determines grain weight and affects grain quality. Several major quantitative trait loci (QTLs) regulating grain size have been cloned; however, our understanding of the underlying mechanism that regulates the size of rice grains remains fragmentary. Here, we report the cloning and characterization of a dominant QTL, GRAIN SIZE ON CHROMOSOME 2 (GS2), which encodes Growth-Regulating Factor 4 (OsGRF4), a transcriptional regulator. GS2 localizes to the nucleus and may act as a transcription activator. A rare mutation of GS2 affecting the binding site of a microRNA, OsmiR396c, causes elevated expression of GS2/OsGRF4. The increase in GS2 expression leads to larger cells and increased numbers of cells, which thus enhances grain weight and yield. The introduction of this rare allele of GS2/OsGRF4 into rice cultivars could significantly enhance grain weight and increase grain yield, with possible applications in breeding high-yield rice varieties. 展开更多
关键词 GS2 OsGRF4 QTL grain size miR396c RICE
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Diagnostic criteria for autoimmune chronic pancreatitis revisited 被引量:73
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作者 Kyu-Pyo Kim Myung-Hwan Kim +3 位作者 Jong Cheol Kim Sang Soo Lee dong Wan Seo Sung Koo Lee 《World Journal of Gastroenterology》 SCIE CAS CSCD 2006年第16期2487-2496,共10页
Autoimmune chronic pancreatitis (AIP) is increasingly being recognized worldwidely, as knowledge of this entity builds up. Above all, AIP is a very attractive disease to clinicians in terms of its dramatic response ... Autoimmune chronic pancreatitis (AIP) is increasingly being recognized worldwidely, as knowledge of this entity builds up. Above all, AIP is a very attractive disease to clinicians in terms of its dramatic response to the oral steroid therapy in contrast to ordinary chronic pancreatitis. Although many characteristic findings of AIP have been described, definite diagnostic criteria have not been fully established. In the year 2002, the Japan Pancreas Society published the diagnostic criteria of AIP and many clinicians around the world use these criteria for the diagnosis of AIP. The diagnostic criteria proposed by the Japan Pancreas Society, however, are not completely satisfactory and some groups use their own criteria in reporting AIP. This review discusses several potential limitations of current diagnostic criteria for this increasingly recognized condition. The manuscript is organized to emphasize the need for convening a consensus to develop improved diagnostic criteria. 展开更多
关键词 Autoimmune chronic pancreatitis Diagnostic criteria
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