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Analysis of status and countermeasures of cancer incidence and mortality in China 被引量:207
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作者 Chunchun Wu Mengna Li +10 位作者 Hanbing Meng Yukun Liu Weihong Niu Yao Zhou ran Zhao Yumei Duan Zhaoyang Zeng Xiaoling Li Guiyuan Li Wei Xiong Ming Zhou 《Science China(Life Sciences)》 SCIE CAS CSCD 2019年第5期640-647,共8页
Cancer is the leading cause of human deaths in the world and produces serious economic burdens. On September 12, 2018, the academic journal A Cancer Journal for Clinicians published an article about the latest statist... Cancer is the leading cause of human deaths in the world and produces serious economic burdens. On September 12, 2018, the academic journal A Cancer Journal for Clinicians published an article about the latest statistics of cancers worldwide, which provided a status report on the global burden of 36 cancers in 185 countries worldwide. Cancer has also become a serious public health problem in China and caused more and more attention of the government and people in recent years. This review analyzes the incidence, mortality and prevalent trend of cancers in China, discusses the reasons behind this status, and reviews the potential countermeasures for cancer prevention and control in China. 展开更多
关键词 CANCER INCIDENCE MORTALITY CANCER SPECTRUM COUNTERMEASURES
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Research progress of the fractional Fourier transform in signal processing 被引量:100
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作者 TAO ran DENG Bing WANG Yue 《Science in China(Series F)》 2006年第1期1-25,共25页
The fractional Fourier transform is a generalization of the classical Fourier transform, which is introduced from the mathematic aspect by Namias at first and has many applications in optics quickly. Whereas its poten... The fractional Fourier transform is a generalization of the classical Fourier transform, which is introduced from the mathematic aspect by Namias at first and has many applications in optics quickly. Whereas its potential appears to have remained largely unknown to the signal processing community until 1990s. The fractional Fourier transform can be viewed as the chirp-basis expansion directly from its definition, but essentially it can be interpreted as a rotation in the time-frequency plane, i.e. the unified time-frequency transform. With the order from 0 increasing to 1, the fractional Fourier transform can show the characteristics of the signal changing from the time domain to the frequency domain. In this research paper, the fractional Fourier transform has been comprehensively and systematically treated from the signal processing point of view. Our aim is to provide a course from the definition to the applications of the fractional Fourier transform, especially as a reference and an introduction for researchers and interested readers. 展开更多
关键词 fractional Fourier transform signal processing time-frequency analysis.
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The China Alzheimer Report 2022 被引量:88
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作者 Rujing Ren Jinlei Qi +21 位作者 Shaohui Lin Xinya Liu Peng Yin Zhihui Wang ran Tang Jintao Wang Qiang Huang Jianping Li Xinyi Xie Yongbo Hu Shishuang Cui Yuan Zhu Xiaoping Yu Pengfei Wang Yikang Zhu Yiran Wang Yanyan Huang Yisong Hu Ying Wang Chunbo Li Maigeng Zhou Gang Wang 《General Psychiatry》 CSCD 2022年第1期1-19,共19页
China’s population has rapidly aged over the recent decades of social and economic development as neurodegenerative disorders have proliferated,especially Alzheimer’s disease(AD)and related dementias(ADRD).AD’s inc... China’s population has rapidly aged over the recent decades of social and economic development as neurodegenerative disorders have proliferated,especially Alzheimer’s disease(AD)and related dementias(ADRD).AD’s incidence rate,morbidity,and mortality have steadily increased to make it presently the fifth leading cause of death among urban and rural residents in China and magnify the resulting financial burdens on individuals,families and society.The‘Healthy China Action’plan of 2019-2030 promotes the transition from disease treatment to health maintenance for this expanding population with ADRD.This report describes related epidemiological trends,evaluates the economic burden of the disease,outlines current clinical diagnosis and treatment status and delineates existing available public health resources.More specifically,it examines the public health impact of ADRD,including prevalence,mortality,costs,usage of care,and the overall effect on caregivers and society.In addition,this special report presents technical guidance and supports for the prevention and treatment of AD,provides expertise to guide relevant governmental healthcare policy development and suggests an information platform for international exchange and cooperation. 展开更多
关键词 ALZHEIMER MORTALITY PREVENTION
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炎热多雨气候下花岗岩残积土的强度衰减与微结构损伤规律 被引量:55
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作者 安然 孔令伟 +1 位作者 黎澄生 罗晓倩 《岩石力学与工程学报》 EI CAS CSCD 北大核心 2020年第9期1902-1911,共10页
对花岗岩残积土开展反复干湿循环下的三轴固结不排水(CU)剪切试验与核磁共振成像(MRI)扫描试验,通过应力–应变关系、抗剪强度参数、孔隙体积含量等指标,评价炎热多雨气候对土体性质的损伤效应。研究结果表明:经历0~2次干湿循环的残积... 对花岗岩残积土开展反复干湿循环下的三轴固结不排水(CU)剪切试验与核磁共振成像(MRI)扫描试验,通过应力–应变关系、抗剪强度参数、孔隙体积含量等指标,评价炎热多雨气候对土体性质的损伤效应。研究结果表明:经历0~2次干湿循环的残积土的应力–应变关系曲线在低围压下表现为应变软化型,在高围压下表现为弱应变硬化型,经历3次以上干湿循环的土体应力–应变曲线均为弱应变硬化型;随着循环次数增加,残积土的有效黏聚力和有效内摩擦角逐渐减小,且有效黏聚力的衰减幅度明显更大;通过求解表面弛豫系数,经由T2分布曲线获得了孔隙体积分布曲线,并根据直径将孔隙划分为微孔隙和裂隙;微孔隙的含量随干湿循环次数增加略有减小,裂隙的含量大幅增长;孔隙体积含量与有效抗剪强度指标呈负相关的线性关系,表明力学性能与孔隙结构的演化特征具有同步性;干湿循环对花岗岩残积土的损伤效应主要是由脱湿时的基质吸力增长、吸湿时的孔隙壁膨胀及胶结物分解、流失引起的。 展开更多
关键词 土力学 花岗岩残积土 干湿循环 三轴剪切试验 核磁共振成像 强度指标 孔隙结构
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Channel change at Toudaoguai Station and its responses to the operation of upstream reservoirs in the upper Yellow River 被引量:53
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作者 ran Lishan WANG Suiji FAN Xiaoli 《Journal of Geographical Sciences》 SCIE CSCD 2010年第2期231-247,共17页
The application of dams built upstream will change the input conditions, including water and sediment, of downstream fluvial system, and destroy previous dynamic quasi-equilibrium reached by channel streamflow, so ind... The application of dams built upstream will change the input conditions, including water and sediment, of downstream fluvial system, and destroy previous dynamic quasi-equilibrium reached by channel streamflow, so indispensable adjustments are necessary for downstream channel to adapt to the new water and sediment supply, leading the fluvial system to restore its previous equilibrium or reach a new equilibrium. Using about 50-year-long hydrological, sedimentary and cross-sectional data, temporal response processes of Toudaoguai cross-section located in the upper Yellow River to the operation of reservoirs built upstream are analyzed. The results show that the Toudaoguai cross-section change was influenced strongly by upstream reservoir operation and downstream channel bed armoring thereafter occurred gradually and extended to the reach below Sanhuhekou gauging station. Besides, median diameter of suspended sediment load experienced a three-stage change that is characterized by an increase at first, then a decrease and an increase again finally, which reflects the process of channel bed armoring that began at Qingtongxia reservoir and then gradually developed downstream to the reach below Sanhuhekou cross-section. Since the joint operation strategy of Longyangxia, Liujiaxia and Qingtongxia reservoirs was introduced in 1986, the three-stage change trend has become less evident than that in the time period between 1969 and 1986 when only Qingtongxia and Liujiaxia reservoirs were put into operation alone. In addition, since 1987, the extent of lateral migration and thalweg elevation change at Toudaoguai cross-section has reduced dramatically, cross-sectional profile and location tended to be stable, which is beneficial to the normal living for local people. 展开更多
关键词 cross-sectional profile median diameter reservoir Toudaoguai cross-section the upper Yellow River
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Natural Variation in the Promoter of GSE5 Contributes to Grain Size Diversity in Rice 被引量:48
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作者 Penggen Duan Jinsong Xu +9 位作者 Dali Zeng Baolan Zhang Mufan Geng Guozheng Zhang Ke Huang Luojiang Huang ran Xu Song Ge Qian Qian Yunhai Li 《Molecular Plant》 SCIE CAS CSCD 2017年第5期685-694,共10页
The utilization of natural genetic variation greatly contributes to improvement of important agronomic traits in crops. Understanding the genetic basis for natural variation of grain size can help breeders develop hig... The utilization of natural genetic variation greatly contributes to improvement of important agronomic traits in crops. Understanding the genetic basis for natural variation of grain size can help breeders develop high- yield rice varieties. In this study, we identify a previously unrecognized gene, named GSE5, in the qSW5/ GW5 locus controlling rice grain size by combining the genome-wide association study with functional analyses. GSE5 encodes a plasma membrane-associated protein with |Q domains, which interacts with the rice calmodulin protein, OsCaMl-1. We found that loss of GSE5 function caused wide and heavy grains, while overexpression of GSE5 resulted in narrow grains. We showed that GSE5 regulates grain size predominantly by influencing cell proliferation in spikelet hulls. Three major haplotypes of GSE5 (GSE5, GSE5DELl+IN1, and GSESDEL~ in cultivated rice were identified based on the deletion/insertion type in its pro- moter region. We demonstrated that a 950-bp deletion (DELl) in indica varieties carrying the GSE5DELl+IN1 haplotype and a 1212-bp deletion (DEL2) in japonica varieties carrying the GSE5DEL2 haplotype associated with decreased expression of GSE5, resulting in wide grains. Further analyses indicate that wild rice acces- sions contain all three haplotypes of GSE5, suggesting that the GSE5 haplotypes present in cultivated rice are likely to have originated from different wild rice accessions during rice domestication. Taken together, our results indicate that the previously unrecognized GSE5 gene in the qSW5/GW5 locus, which is widely utilized by rice breeders, controls grain size, and reveal that natural variation in the promoter region of GSE5 contributes to grain size diversity in rice. 展开更多
关键词 RICE natural variation GSE5 grain size cell proliferation
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基于数据驱动和深度置信网络的配电网无功优化 被引量:48
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作者 邵美阳 吴俊勇 +4 位作者 石琛 安然 朱孝文 黄杏 蔡蓉 《电网技术》 EI CSCD 北大核心 2019年第6期1874-1883,共10页
随着分布式电源和随机负荷电动汽车等的大量接入,配电网的运行环境日益复杂,对在线无功优化及其快速性提出了更高的要求。该文将“深度学习”引入配电网无功优化,提出了基于深度置信网络的无功优化方法。通过构造高维随机矩阵,从配电网... 随着分布式电源和随机负荷电动汽车等的大量接入,配电网的运行环境日益复杂,对在线无功优化及其快速性提出了更高的要求。该文将“深度学习”引入配电网无功优化,提出了基于深度置信网络的无功优化方法。通过构造高维随机矩阵,从配电网运行数据中提取统计特征作为输入,将历史控制策略进行编码作为输出,利用先无监督后有监督的方式训练深层架构,学习系统特征与无功优化策略之间的映射关系,建立基于数据驱动和深度置信网络的配电网无功优化模型。基于改造的IEEE-37节点主动配电网仿真模型,对比分析了历史数据量和分布式电源渗透率场景对传统优化方法,场景匹配方法和所提方法的无功优化效果的影响。结果表明,所提方法可明显降低网络损耗和节点电压偏移,它不依赖于系统的模型和参数,在线决策速度快,且对历史数据量要求较低,在高渗透率分布式发电等未知场景下仍能表现优良,验证了该方法的正确性、有效性和较强的鲁棒性。 展开更多
关键词 深度置信网络 深度学习 配电网 无功优化 数据驱动
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湖南省某典型流域农用地土壤重金属污染及影响因素 被引量:45
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作者 沈洪艳 安冉 +2 位作者 师华定 刘孝阳 张安迪 《环境科学研究》 EI CAS CSCD 北大核心 2021年第3期715-724,共10页
农田土壤环境直接关系到农产品质量安全,是维系“菜篮子”工程、保障“吃的放心”的重要基础,近年来受到广泛关注.为探明农田土壤重金属污染分布特征及主要影响因子,以污染问题突出、地势起伏较大、水网密布的我国湖南省某典型流域为研... 农田土壤环境直接关系到农产品质量安全,是维系“菜篮子”工程、保障“吃的放心”的重要基础,近年来受到广泛关注.为探明农田土壤重金属污染分布特征及主要影响因子,以污染问题突出、地势起伏较大、水网密布的我国湖南省某典型流域为研究区,以流域主干河流沿线的农田土壤为研究对象,借助单因子指数、内梅罗指数和潜在生态危害指数,综合评价土壤Cd、Hg、As、Pb、Cr这5种重金属的污染状况;结合多元统计分析与地统计分析的方法,分析土地利用类型、地形因子与重金属含量的关系,并对土壤重金属空间分布和污染来源进行探究.结果表明:①研究区土壤Cd、Hg、As、Pb、Cr的平均含量分别为1.59、0.19、33.01、229.95、72.78 mg kg.其中,Cd、As、Pb的平均含量均超过研究区土壤背景值.②内梅罗指数分析显示,研究区中77.16%的土壤点位评价结果为重度污染;与GB 15618—2018《土壤环境质量农用地土壤污染风险管控标准(试行)》中农用地土壤污染风险管制值相比,土壤点位中Cd、As、Pb超标现象突出,主要分布于流域上游西部;综合潜在生态危害评价结果表明,3.05%的土壤点位表现为强生态风险及以上.③不同土地利用类型中,土壤重金属含量存在显著差异.旱地、水田、果园土壤中Cd、Hg、As、Pb的含量依次降低.高程与各重金属(除Hg外)含量均呈显著相关(P<0.05),坡度、坡向与各重金属含量的相关性均不显著(P<0.05).④源解析结果表明,流域农田土壤中Cd、As、Pb受到工业生产活动、交通运输、农业活动的综合影响,Hg、Cr主要来源于成土母质等自然因素.研究显示,研究区土壤中重金属存在一定程度的污染,重金属富集受土地利用类型、高程及人为因素的影响较明显. 展开更多
关键词 农田土壤 污染评价 空间分布 流域 重金属
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Control of Grain Size and Weight by the OsMKKK10-OsM KK4-OsMAPK6 Signaling Pathway in Rice 被引量:45
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作者 ran Xu Penggen Duan +12 位作者 Haiyue Yu Zhengkui Zhou Baolan Zhang Ruci Wang Jing Li Guozheng Zhang Shangshang Zhuang Jia Lyu Na Li Tuanyao Chai Zhixi Tian Shanguo Yao Yunhai Li 《Molecular Plant》 SCIE CAS CSCD 2018年第6期860-873,共14页
Grain size is one of the key agronomic traits that determine grain yield in crops. However, the mechanisms underlying grain size control in crops remain elusive. Here we demonstrate that the OsMKKK10-OsMKK4- OsMAPK6 s... Grain size is one of the key agronomic traits that determine grain yield in crops. However, the mechanisms underlying grain size control in crops remain elusive. Here we demonstrate that the OsMKKK10-OsMKK4- OsMAPK6 signaling pathway positively regulates grain size and weight in rice. In rice, loss of OsMKKKIO function results in small and light grains, short panicles, and semi-dwarf plants, while overexpression of constitutively active OsMKKK10 (CA-OsMKKK10) results in large and heavy grains, long panicles, and tall plants. OsMKKK10 interacts with and phosphorylates OsMKK4. We identified an OsMKK4 gain-of-func- tion mutant (large11-1D)that produces large and heavy grains. OsMKK4A227T encoded by the large11-1D allele has stronger kinase activity than OsMKK4. Plants overexpressing a constitutively active form of OsMKK4 (OsMKK4oDD) also produce large grains. Further biochemical and genetic analyses revealed that OsMKKK10, OsMKK4, and OsMAPK6 function in a common pathway to control grain size. Taken together, our study establishes an important genetic and molecular framework for OsMKKK10-OsMKK4- OsMAPK6 cascade-mediated control of grain size and weight in rice. 展开更多
关键词 Oryza sativa grain size MAPK signaling cell proliferation
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基于高通量测序的黄河三角洲4种人工林土壤细菌结构及多样性研究 被引量:42
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作者 丁新景 黄雅丽 +4 位作者 敬如岩 马风云 安然 田琪 陈博杰 《生态学报》 CAS CSCD 北大核心 2018年第16期5857-5864,共8页
为研究黄河三角洲不同人工林土壤细菌群落特征,应用高通量测序技术,比较分析了刺槐、榆树、白蜡、臭椿4种人工林土壤细菌结构及多样性,并结合土壤理化性质进行相关性分析。结果表明:人工林土壤中共有31门细菌;4种人工林土壤中酸杆菌门... 为研究黄河三角洲不同人工林土壤细菌群落特征,应用高通量测序技术,比较分析了刺槐、榆树、白蜡、臭椿4种人工林土壤细菌结构及多样性,并结合土壤理化性质进行相关性分析。结果表明:人工林土壤中共有31门细菌;4种人工林土壤中酸杆菌门、变形菌门、放线菌门细菌以及刺槐、臭椿人工林土壤中硝化螺旋菌门细菌是土壤中的优势群落。不同人工林土壤中酸杆菌门、变形菌门、硝化螺旋菌门、芽单胞菌门、拟杆菌门、广古菌门、泉古菌门、蓝藻菌门细菌丰度差异显著。刺槐人工林土壤细菌多样性最高;白蜡人工林土壤细菌多样性最低。土壤pH、含水量、有机质含量与酸杆菌门细菌丰度呈显著负相关关系,土壤pH与变形菌门、硝化螺旋菌门、芽单胞菌门细菌丰度呈极显著正相关关系;土壤pH、有效磷含量与人工林细菌多样性呈显著正相关关系。以上研究结果表明,黄河三角洲不同人工林土壤细菌群落存在一定差异,土壤pH、含水量、有机质、有效磷含量是影响土壤细菌结构和多样性的主要土壤因素。 展开更多
关键词 黄河三角洲 人工林土壤 细菌结构 多样性 高通量测序
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Local“Land Finance”in China's Urban Expansion:Challenges and Solutions 被引量:41
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作者 Changchun Feng Changchun Feng ran Tao 《China & World Economy》 SCIE 2008年第2期19-30,共12页
This paper considers the issue of local "land finance'" in the context of China "s fast urban expansion. In an analysis of China "s land requisition and public leasing system we argue that low-cost land acquisiti... This paper considers the issue of local "land finance'" in the context of China "s fast urban expansion. In an analysis of China "s land requisition and public leasing system we argue that low-cost land acquisition is the fundamental cause of land-related distortions that have occurred during China "s urbanization. Granting farmers the power to negotiate directly with land users during urban expansion, combined with coordinated land tax reforms to consolidate local tax bases is the key to China achieving both equity and land use efficiency in urban expansion. 展开更多
关键词 land requisition public leasing system urban expansion
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Oral berberine improves brain dopa/dopamine levels to ameliorate Parkinson’s disease by regulating gut microbiota 被引量:39
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作者 Yan Wang Qian Tong +17 位作者 Shu-Rong Ma Zhen-Xiong Zhao Li-Bin Pan Lin Cong Pei Han ran Peng Hang Yu Yuan Lin Tian-Le Gao Jia-Wen Shou Xiao-Yang Li Xian-Feng Zhang Zheng-Wei Zhang Jie Fu Bao-Ying Wen Jin-Bo Yu Xuetao Cao Jian-Dong Jiang 《Signal Transduction and Targeted Therapy》 SCIE CSCD 2021年第3期1001-1020,共20页
The phenylalanine-tyrosine-dopa-dopamine pathway provides dopamine to the brain.Iin this process,tyrosine hydroxylase(TH)isthe rate-limiting enzyme that hydroxylates tyrosine and generates levodopa(L-dopa)with tetrany... The phenylalanine-tyrosine-dopa-dopamine pathway provides dopamine to the brain.Iin this process,tyrosine hydroxylase(TH)isthe rate-limiting enzyme that hydroxylates tyrosine and generates levodopa(L-dopa)with tetranydrobiopterin(BH_(4))as a coenzyme.Here,we show that oral berberine(BBR)might supply H^(·) through dihydroberberine(reduced BBR produced by bacterial nitroreductase)and promote the production of BHl from dihydrobiopterin;the increased BH,enhances TH activity,which accelerates the production of L-dopa by the gut bacteria.Oral BBR acts in a way similar to vitamins.The L-dopa produced by theintestinal bacteria enters the brain through the circulation and is transformed to dopamine.To verify the gut-brain dialog activatedby BBR's effect,Enterococcus foecalis or Enterococcus faecium was transplanted into Parkinson's disease(PD)mice.The bacteriasignificantly increased brain dopamine and ameliorated PD manifestation in mice;additionally,combination of BBR with bacteriashowed better therapeutic effect than that with bacteria alone.Moreover,2,4,6-trimethy-pyranylium tetrafluoroborate(TMP-TFB)-derivatized matrix-assisted laser desorption mass spectrometry(MALDI-MS)imaging of dopamine identihed elevated striataldopamine levels in mouse brains with oral Enterococcus,and BBR strengthened the imaging intensity of brain dopamine.Theseresults demonstrated that BBR was an agonist of TH in Enterococcus and could lead to the production of L-dopa in the gut.Furthermore,a study of 28 patients with hyperlipidemia conhrmed that oral BBR increased bloodfecal L-dopa by the intestinalbacteria.Hence,BBR might improve the brain function by upregulating the biosynthesis of-dopa in the gut microbiota through avitamin-like effect. 展开更多
关键词 DOPAMINE BERBERINE VITAMIN
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Laparoscopic common bile duct exploration with primary closure is safe for management of choledocholithiasis in elderly patients 被引量:35
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作者 Xiang Wu Ze-Jian Huang +3 位作者 Jin-Yi Zhong Yi-Hong ran Ming-Lei Ma Hong-Wei Zhang 《Hepatobiliary & Pancreatic Diseases International》 SCIE CAS CSCD 2019年第6期557-561,共5页
Background:Laparoscopic common bile duct exploration(LCBDE)is one of the minimally invasive options for choledocholithiasis.Primary closure of the common bile duct(CBD)upon completion of laparoscopic choledochotomy is... Background:Laparoscopic common bile duct exploration(LCBDE)is one of the minimally invasive options for choledocholithiasis.Primary closure of the common bile duct(CBD)upon completion of laparoscopic choledochotomy is safe in selected patients.The present study aimed to evaluate the feasibility and safety of primary closure of CBD after LCBDE in patients aged 70 years or older.Methods:A total of 116 patients(51 males and 65 females)who suffered from choledocholithiasis and underwent primary closure of the CBD(without T-tube drainage)after LCBDE from January 2003 to December 2017 were recruited.They were classified into two groups according to age:group A(≥70 years,n=56),and group B(<70 years,n=60).The preoperative characteristics,intraoperative details,and postoperative outcomes of the two groups were evaluated.Results:The mean operative time was 172.02 min for group A and 169.92 min for group B(P=0.853).The mean hospital stay was 7.40 days for group A and 5.38 days for group B(P<0.001).Bile leakage occurred in two patients in group A and one in group B(3.57%vs 1.67%,P=0.952).There were no significant differences in the rates of postoperative complications and mortality between the two groups.At median follow-up time of 60 months,stone recurrence was detected in one patient in group A and two in group B(1.79%vs 3.33%,P=1.000).Stenosis of CBD was not observed in group A and slight stenosis in one patient in group B(0 vs 1.67%,P=1.000).Conclusion:Primary closure of the CBD upon completion of laparoscopic choledochotomy is safe and feasible in elderly patients≥70 years old. 展开更多
关键词 LAPAROSCOPY CHOLEDOCHOTOMY Primary CLOSURE ELDER
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Rhizospheric microbial communities are driven by Panax ginseng at different growth stages and biocontrol bacteria alleviates replanting mortality 被引量:34
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作者 Linlin Dong Jiang Xu +7 位作者 Lianjuan Zhang Ruiyang Cheng Guangfei Wei He Su Juan Yang Jun Qian ran Xu Shilin Chen 《Acta Pharmaceutica Sinica B》 SCIE CAS CSCD 2018年第2期272-282,共11页
The cultivation of Panax plants is hindered by replanting problems, which may be caused by plantdriven changes in the soil microbial community. Inoculation with microbial antagonists may efficiently alleviate replanti... The cultivation of Panax plants is hindered by replanting problems, which may be caused by plantdriven changes in the soil microbial community. Inoculation with microbial antagonists may efficiently alleviate replanting issues. Through high-throughput sequencing, this study revealed that bacterial diversity decreased,whereas fungal diversity increased, in the rhizosphere soils of adult ginseng plants at the root growth stage under different ages. Few microbial community, such as Luteolibacter, Cytophagaceae, Luteibacter, Sphingomonas,Sphingomonadaceae, and Zygomycota, were observed; the relative abundance of microorganisms, namely,Brevundimonas, Enterobacteriaceae, Pandoraea, Cantharellales, Dendryphion, Fusarium, and Chytridiomycota,increased in the soils of adult ginseng plants compared with those in the soils of 2-year-old seedlings. Bacillus subtilis 50-1, a microbial antagonist against the pathogenic Fusarium oxysporum, was isolated through a dual culture technique. These bacteria acted with a biocontrol efficacy of 67.8%. The ginseng death rate and Fusarium abundance decreased by 63.3% and 46.1%, respectively, after inoculation with B. subtilis 50-1. Data revealed that microecological degradation could result from ginseng-driven changes in rhizospheric microbial communities;these changes are associated with the different ages and developmental stages of ginseng plants. Biocontrol using microbial antagonists alleviated the replanting problem. 展开更多
关键词 Panax ginseng Microbial communities Replanting problem High-throughput sequencing Different ages BIOREMEDIATION
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Abnormal metabolism of gut microbiota reveals the possible molecular mechanism of nephropathy induced by hyperuricemia 被引量:34
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作者 Libin Pan Pei Han +9 位作者 Shurong Ma ran Peng Can Wang Weijia Kong Lin Cong Jie Fu Zhengwei Zhang Hang Yu Yan Wang Jiandong Jiang 《Acta Pharmaceutica Sinica B》 SCIE CAS CSCD 2020年第2期249-261,共13页
The progression of hyperuricemia disease is often accompanied by damage to renal function.However,there are few studies on hyperuricemia nephropathy,especially its association with intestinal flora.This study combines... The progression of hyperuricemia disease is often accompanied by damage to renal function.However,there are few studies on hyperuricemia nephropathy,especially its association with intestinal flora.This study combines metabolomics and gut microbiota diversity analysis to explore metabolic changes using a rat model as well as the changes in intestinal flora composition.The results showed that amino acid metabolism was disturbed with serine,glutamate and glutamine being downregulated whilst glycine,hydroxyproline and alanine being upregulated.The combined glycine,serine and glutamate could predict hyperuricemia nephropathy with an area under the curve of 1.00.Imbalanced intestinal flora was also observed.Flavobacterium,Myroides,Corynebacterium,Alcaligenaceae,Oligella and other conditional pathogens increased significantly in the model group,while Blautia and Roseburia,the shortchain fatty acid producing bacteria,declined greatly.At phylum,family and genus levels,disordered nitrogen circulation in gut microbiota was detected.In the model group,the uric acid decomposition pathway was enhanced with reinforced urea liver-intestine circulation.The results implied that the intestinal flora play a vital role in the pathogenesis of hyperuricemia nephropathy.Hence,modulation of gut microbiota or targeting at metabolic enzymes,i.e.,urease,could assist the treatment and prevention of this disease. 展开更多
关键词 HYPERURICEMIA Renal function GUT MICROBIOTA Metabolomics UREASE
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Backstepping design of missile guidance and control based on adaptive fuzzy sliding mode control 被引量:33
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作者 ran Maopeng Wang Qing +1 位作者 Hou Delong Dong Chaoyang 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2014年第3期634-642,共9页
This paper presents an integrated missile guidance and control law based on adaptive fuzzy sliding mode control. The integrated model is formulated as a block-strict-feedback nonlinear system, in which modeling errors... This paper presents an integrated missile guidance and control law based on adaptive fuzzy sliding mode control. The integrated model is formulated as a block-strict-feedback nonlinear system, in which modeling errors, unmodeled nonlinearities, target maneuvers, etc. are viewed as unknown uncertainties. The adaptive nonlinear control law is designed based on backstepping and sliding mode control techniques. An adaptive fuzzy system is adopted to approximate the coupling nonlinear functions of the system, and for the uncertainties, we utilize an online-adaptive control law to estimate the unknown parameters. The stability analysis of the closed-loop system is also conducted. Simulation results show that, with the application of the adaptive fuzzy sliding mode control, small miss distances and smooth missile trajectories are achieved, and the system is robust against system uncertainties and external disturbances. 展开更多
关键词 Adaptive fuzzy system BACKSTEPPING Integrated guidance and control NONLINEAR Sliding mode control
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Nutrition and physical activity in NAFLD:An overview of the epidemiological evidence 被引量:33
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作者 Shira Zelber-Sagi ran Oren +1 位作者 Zelber-Sagi Vlad Ratziu 《World Journal of Gastroenterology》 SCIE CAS CSCD 2011年第29期3377-3389,共13页
Nonalcoholic fatty liver disease(NAFLD)has been recognized as a major health burden.The high prevalence of NAFLD is probably due to the contemporary epidemics of obesity,unhealthy dietary pattern,and sedentary lifesty... Nonalcoholic fatty liver disease(NAFLD)has been recognized as a major health burden.The high prevalence of NAFLD is probably due to the contemporary epidemics of obesity,unhealthy dietary pattern,and sedentary lifestyle.The efficacy and safety profile of pharmacotherapy in the treatment of NAFLD remains uncertain and obesity is strongly associated with hepatic steatosis;therefore,the first line of treatment is lifestyle modification.The usual management of NAFLD includes gradual weight reduction and increased physical activity(PA)leading to an improvement in serum liver enzymes,reduced hepatic fatty infiltration,and,in some cases,a reduced degree of hepatic inflammation and fibrosis.Nutrition has been demonstrated to be associated with NAFLD and Non-alcoholic steatohepatitis(NASH)in both animals and humans,and thus serves as a major route of prevention and treatment.However,most human studies are observational and retrospective,allowing limited inference about causal associations.Large prospective studies and clinical trials are now needed to establish a causal relationship.Based on available data,patients should optimally achieve a 5%-10%weight reduction.Setting realistic goals is essential for long-term successful lifestyle modification and more effort must be devoted to informing NAFLD patients of the health benefits of even a modest weight reduction.Furthermore,all NAFLD patients,whether obese or of normal weight,should be informed that a healthy diet has benefits beyond weight reduction.They should be advised to reduce saturated/trans fat and increase polyunsaturated fat,with special emphasize on omega-3 fatty acids.They should reduce added sugar to its minimum,try to avoid soft drinks containing sugar,including fruit juices that contain a lot of fructose,and increase their fiber intake.For the heavy meat eaters,especially those of red and processed meats,less meat and increased fish intake should be recommended.Minimizing fast food intake will also help maintain a healthy diet.PA should be integrated into b 展开更多
关键词 Nonalcoholic fatty liver disease NUTRITION Physical activity Weight reduction FAT Carbohydrates Soft drinks NUTRIENTS
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Experimental Study of the Pressure Fluctuations in a Pump Turbine at Large Partial Flow Conditions 被引量:33
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作者 ran Hongjuan LUO Xianwu +3 位作者 ZHU Lei ZHANG Yao WANG Xin XU Hongyuan 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2012年第6期1205-1209,共5页
Frequent shifts of output and operating mode require a pump turbine with excellent stability. Current researches show that large partial flow conditions in pump mode experience positive-slope phenomena with a large he... Frequent shifts of output and operating mode require a pump turbine with excellent stability. Current researches show that large partial flow conditions in pump mode experience positive-slope phenomena with a large head drop. The pressure fluctuation at the positive slope is crucial to the pump turbine unit safety. The operating instabilities at large partial flow conditions for a pump turbine are analyzed. The hydraulic performance of a model pump turbine is tested with the pressure fluctuations measured at unstable operating points near a positive slope in the performance curve. The hydraulic performance tests show that there are two separated positive-slope regions for the pump turbine, with the flow discharge for the first positive slope from 0.85 to 0.91 times that at the maximum efficiency point. The amplitudes of the pressure fluctuations at these unstable large partial flow conditions near the first positive slope are much larger than those at stable operating condtions. A dominant frequency is measured at 0.2 times the impeller rotational frequency in the flow passage near the impeller exit, which is believed to be induced by the rotating stall in the flow passage of the wicket gates. The test results also show hysteresis with pressure fluctuations when the pump turbine is operated near the first positive slope. The hysteresis creates different pressure fluctuations for those operation points even though their flow rates and heads are similar respectively. The pressure fluctuation characteristics at large partial flow conditions obtained by the present study will be helpful for the safe operation of pumped storage units. 展开更多
关键词 positive slope pressure fluctuation rotating stall pump turbine
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A journey to understand wheat Fusarium head blight resistance in the Chinese wheat landrace Wangshuibai 被引量:31
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作者 Haiyan Jia Jiyang Zhou +9 位作者 Shulin Xue Guoqiang Li Haisheng Yan Congfu ran Yiduo Zhang Jinxing Shi Li Jia Xin Wang Jing Luo Zhengqiang Ma 《The Crop Journal》 SCIE CAS CSCD 2018年第1期48-59,共12页
Fusarium head blight(FHB) or scab caused by Fusarium graminearum is a major threat to wheat production in China as well as in the world. To combat this disease, multiple efforts have been carried out internationally. ... Fusarium head blight(FHB) or scab caused by Fusarium graminearum is a major threat to wheat production in China as well as in the world. To combat this disease, multiple efforts have been carried out internationally. In this article, we review our long-time effort in identifying the resistance genes and dissecting the resistance mechanisms by both forward and reverse genetics approaches in the last two decades. We present recent progress in resistance QTL identification, candidate functional gene discovery, marker-assisted improvement of FHB resistant varieties, and findings in investigating association of signal molecules, such as Ca^(++),SA, JA, and ET, with FHB response, with the assistance from rapidly growing genomics platforms. The information will be helpful for designing novel and efficient approaches to curb FHB. 展开更多
关键词 FUSARIUM head blight QTL Gene discovery Marker-assisted selection TRITICUM AESTIVUM
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Parameters of Coseismic Reverse- and Oblique-Slip Surface Ruptures of the 2008 Wenchuan Earthquake,Eastern Tibetan Plateau 被引量:31
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作者 XU Xiwei YU Guihua +4 位作者 CHEN Guihua ran Yongkang LI Chenxia CHEN Yuegau CHANG Chungpai 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2009年第4期673-684,共12页
On May 12th, 2008, the Mw7.9 Wenchuan earthquake ruptured the Beichuan, Pengguan and Xiaoyudong faults simultaneously along the middle segment of the Longmenshan thrust belt at the eastern margin of the Tibetan platea... On May 12th, 2008, the Mw7.9 Wenchuan earthquake ruptured the Beichuan, Pengguan and Xiaoyudong faults simultaneously along the middle segment of the Longmenshan thrust belt at the eastern margin of the Tibetan plateau. Field investigations constrain the surface rupture pattern, length and offsets related to the Wenchuan earthquake. The Beichuan fault has a NE-trending rightlateral reverse rupture with a total length of 240 km. Reassessment yields a maximum vertical offset of 6.5±0.5 m and a maximum right-lateral offset of 4.9±0.5 m for its northern segment, which are the largest offsets found; the maximum vertical offset is 6.2±0.5 m for its southern segment. The Pengguan fault has a NE-trending pure reverse rupture about 72 km long with a maximum vertical offset of about 3.5 m. The Xiaoyudong fault has a NW-striking left-lateral reverse rupture about 7 km long between the Beichuan and Pengguan faults, with a maximum vertical offset of 3.4 m and left-lateral offset of 3.5 m. This pattern of multiple co-seismic surface ruptures is among the most complicated of recent great earthquakes and presents a much larger danger than if they ruptured individually. The rupture length is the longest for reverse faulting events ever reported. 展开更多
关键词 surface rupture zone coseismic offset Wenchuan earthquake LONGMENSHAN
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