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Spatiotemporal characteristics, patterns, and causes of land-use changes in China since the late 1980s 被引量:266
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作者 LIU Jiyuan KUANG Wenhui +13 位作者 ZHANG Zengxiang XU Xinliang qin Yuanwei NING Jia ZHOU Wancun ZHANG Shuwen LI Rendong YAN Changzhe WU shixin shi Xuezheng JIANG Nan YU Dongsheng PAN Xianzhang CHI Wenfeng 《Journal of Geographical Sciences》 SCIE CSCD 2014年第2期195-210,共16页
Land-use/land-cover changes (LUCCs) have links to both human and nature inter- actions. China's Land-Use/cover Datasets (CLUDs) were updated regularly at 5-year inter- vals from the late 1980s to 2010, with stand... Land-use/land-cover changes (LUCCs) have links to both human and nature inter- actions. China's Land-Use/cover Datasets (CLUDs) were updated regularly at 5-year inter- vals from the late 1980s to 2010, with standard procedures based on Landsat TM/ETM+ im- ages. A land-use dynamic regionalization method was proposed to analyze major land-use conversions. The spatiotemporal characteristics, differences, and causes of land-use changes at a national scale were then examined. The main findings are summarized as fol- lows. Land-use changes (LUCs) across China indicated a significant variation in spatial and temporal characteristics in the last 20 years (1990-2010). The area of cropland change de- creased in the south and increased in the north, but the total area remained almost un- changed. The reclaimed cropland was shifted from the northeast to the northwest. The built-up lands expanded rapidly, were mainly distributed in the east, and gradually spread out to central and western China. Woodland decreased first, and then increased, but desert area was the opposite. Grassland continued decreasing. Different spatial patterns of LUC in China were found between the late 20th century and the early 21st century. The original 13 LUC zones were replaced by 15 units with changes of boundaries in some zones. The main spatial characteristics of these changes included (1) an accelerated expansion of built-up land in the Huang-Huai-Hai region, the southeastern coastal areas, the midstream area of the Yangtze River, and the Sichuan Basin; (2) shifted land reclamation in the north from northeast China and eastern Inner Mongolia to the oasis agricultural areas in northwest China; (3) continuous transformation from rain-fed farmlands in northeast China to paddy fields; and (4) effective- ness of the "Grain for Green" project in the southern agricultural-pastoral ecotones of Inner Mongolia, the Loess Plateau, and southwestern mountainous areas. In the last two decades, although climate change 展开更多
关键词 satellite remote sensing land-use change CHARACTERISTICS spatial pattern China
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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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中国南海天然气水合物第二次试采主要进展 被引量:130
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作者 叶建良 秦绪文 +24 位作者 谢文卫 卢海龙 马宝金 邱海峻 梁金强 陆敬安 匡增桂 陆程 梁前勇 魏士鹏 于彦江 刘春生 李彬 申凯翔 史浩贤 卢秋平 李晶 寇贝贝 宋刚 李博 张贺恩 陆红锋 马超 董一飞 边航 《中国地质》 CAS CSCD 北大核心 2020年第3期557-568,共12页
泥质粉砂型天然气水合物被认为是储量最大开采难度亦最大的水合物储层,2017年南海天然气水合物试采,初步验证了此类水合物储层具备可开采性。在总结前次试采认识的基础上,对试采矿体进行优选、精细评价、数值与试验模拟和陆地试验,中国... 泥质粉砂型天然气水合物被认为是储量最大开采难度亦最大的水合物储层,2017年南海天然气水合物试采,初步验证了此类水合物储层具备可开采性。在总结前次试采认识的基础上,对试采矿体进行优选、精细评价、数值与试验模拟和陆地试验,中国地质调查局于2019年10月-2020年4月在南海水深1225 m神狐海域进行了第二次天然气水合物试采。本次试采攻克了钻井井口稳定性、水平井定向钻进、储层增产改造与防砂、精准降压等一系列深水浅软地层水平井技术难题,实现连续产气30 d,总产气量86.14×104m3,日均产气2.87×104m3,是首次试采日产气量的5.57倍,大大提高了日产气量和产气总量。试采监测结果表明,整个试采过程海底、海水及大气甲烷含量无异常。本次成功试采进一步表明,泥质粉砂储层天然气水合物具备可安全高效开采的可行性。 展开更多
关键词 南海天然气水合物 第二次试采 水平井 储层改造 环境影响 油气资源工程 神狐海域 南海
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Plant abiotic stress response and nutrient use efficiency 被引量:118
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作者 Zhizhong Gong Liming Xiong +14 位作者 Huazhong shi Shuhua Yang Luis R.Herrera-Estrella Guohua Xu Dai-Yin Chao Jingrui Li Peng-Yun Wang Feng qin Jigang Li Yanglin Ding Yiting shi Yu Wang Yongqing Yang Yan Guo Jian-Kang Zhu 《Science China(Life Sciences)》 SCIE CAS CSCD 2020年第5期635-674,共40页
Abiotic stresses and soil nutrient limitations are major environmental conditions that reduce plant growth,productivity and quality.Plants have evolved mechanisms to perceive these environmental challenges,transmit th... Abiotic stresses and soil nutrient limitations are major environmental conditions that reduce plant growth,productivity and quality.Plants have evolved mechanisms to perceive these environmental challenges,transmit the stress signals within cells as well as between cells and tissues,and make appropriate adjustments in their growth and development in order to survive and reproduce.In recent years,significant progress has been made on many fronts of the stress signaling research,particularly in understanding the downstream signaling events that culminate at the activation of stress-and nutrient limitation-responsive genes,cellular ion homeostasis,and growth adjustment.However,the revelation of the early events of stress signaling,particularly the identification of primary stress sensors,still lags behind.In this review,we summarize recent work on the genetic and molecular mechanisms of plant abiotic stress and nutrient limitation sensing and signaling and discuss new directions for future studies. 展开更多
关键词 abiotic stress sensing nutrient use efficiency heavy metal Ca2+signaling ROS signal transduction PHOSPHORYLATION transcription factor TRANSPORTER
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Chinese consensus guidelines for diagnosis and management of gastrointestinal stromal tumor 被引量:108
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作者 Jian Li Yingjiang Ye +14 位作者 Jian Wang Bo Zhang Shukui qins Yingqiang shi Yulong He Xiaobo Liang Xiufeng Liu Ye Zhou Xin Wu Xinhua Zhang Ming Wang Zhidong Gao Tianlong Lin Hui Cao Lin Shen 《Chinese Journal of Cancer Research》 SCIE CAS CSCD 2017年第4期281-293,共13页
In order to further promote the standardization of diagnosis and treatment of gastrointestinal stromal tumor (GIST) in China, the members of Chinese Society of Clinical Oncology (CSCO) Expert Committee on GIST tho... In order to further promote the standardization of diagnosis and treatment of gastrointestinal stromal tumor (GIST) in China, the members of Chinese Society of Clinical Oncology (CSCO) Expert Committee on GIST thoroughly discussed the key contents of the consensus guidelines, and voted on the controversial issue. In final, the Chinese consensus guidelines for the diagnosis and management of GIST (2017 edition) was formed on the basis of 2013 edition consensus guidelines, which is hereby announced. The consensus included the pathological diagnosis, recurrence risk classification evaluation, targeted agent therapy, surgery and principles of surveillance of GIST. 展开更多
关键词 Gastrointestinal stromal tumor DIAGNOSIS THERAPY CONSENSUS
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基于区块链的分布式能源交易方案设计综述 被引量:94
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作者 李彬 覃秋悦 +5 位作者 祁兵 孙毅 李德智 石坤 杨斌 奚培锋 《电网技术》 EI CSCD 北大核心 2019年第3期961-972,共12页
以绿色新能源为主体的分布式能源成为能源交易市场中的重要组成部分,为了提高能源利用率、多渠道扩展分布式能源本地消纳,分布式能源获得合法就近售电资质,其能源生产和消费结构呈无中心、多节点状。现有能源运营模式由于具有集中式管... 以绿色新能源为主体的分布式能源成为能源交易市场中的重要组成部分,为了提高能源利用率、多渠道扩展分布式能源本地消纳,分布式能源获得合法就近售电资质,其能源生产和消费结构呈无中心、多节点状。现有能源运营模式由于具有集中式管理的特点,难以简单套用于分布式能源。区块链技术具有可追溯性、交易公开、数据透明的优势,其分散化特性与分布式能源无中心特点相符合,故提出一种基于区块链的分布式能源交易方案。分析现有分布式能源交易的方式及其弊端,研究区块链技术对于分布式能源P2P交易的适用性,在连续双边拍卖(continuousdoubleauction,CDA)、竞争均衡价格(competitive equilibrium price,CEP)、节点信誉值等基础上确立支撑分布式能源P2P交易的分布式能源结算机制,制定符合中国政策的分布式能源区块链支付模式,提出包括系统架构、交易流程在内的基于区块链技术的分布式能源交易方案,对比传统电力交易系统和基于区块链的分布式能源交易系统的性能,思考如何改进目前区块链的不足之处并展望能源市场未来,实现传统电力交易市场向分布式能源交易的延伸性发展。最后,针对区块链技术在实体应用过程中的挑战分析目前电力市场与区块链技术结合所存在的冲突及问题,并提出相应的建议方案。 展开更多
关键词 区块链 分布式能源交易 能源P2P交易 结算机制 电力交易市场
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Dual Functions of Microglia in Ischemic Stroke 被引量:90
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作者 Chuan qin Luo-Qi Zhou +6 位作者 Xiao-Tong Ma Zi-Wei Hu Sheng Yang Man Chen Dale B. Bosco Long-Jun Wu Dai-shi Tian 《Neuroscience Bulletin》 SCIE CAS CSCD 2019年第5期921-933,共13页
Ischemic stroke is a leading cause of morbidity and mortality worldwide. Resident microglia are the principal immune cells of the brain, and the first to respond to the pathophysiological changes induced by ischemic s... Ischemic stroke is a leading cause of morbidity and mortality worldwide. Resident microglia are the principal immune cells of the brain, and the first to respond to the pathophysiological changes induced by ischemic stroke. Traditionally, it has been thought that microglial activation is deleterious in ischemic stroke, and therapies to suppress it have been intensively explored. However,increasing evidence suggests that microglial activation is also critical for neurogenesis, angiogenesis, and synaptic remodeling, thereby promoting functional recovery after cerebral ischemia. Here, we comprehensively review the dual role of microglia during the different phases of ischemic stroke, and the possible mechanisms controlling the post-ischemic activity of microglia. In addition, we discuss the dynamic interactions between microglia and other cells, such as neurons, astrocytes, oligodendrocytes,and endothelial cells within the brain parenchyma and the neurovascular unit. 展开更多
关键词 MICROGLIA INFLAMMATION Ischemic stroke Signaling pathways
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互联网+居家照护平台在肿瘤患者PICC导管延续护理中的应用 被引量:62
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作者 秦月兰 石小毛 +1 位作者 何育兰 刘智群 《中华现代护理杂志》 2019年第8期986-990,共5页
目的探讨互联网+居家照护平台在肿瘤患者PICC导管延续护理中的应用效果。方法采用便利抽样法,选取2017年3—12月在湖南省人民医院住院的173例行PICC置管的肿瘤患者,分为对照组和居家组,其中对照组92例,居家组81例。对照组予常规延续护... 目的探讨互联网+居家照护平台在肿瘤患者PICC导管延续护理中的应用效果。方法采用便利抽样法,选取2017年3—12月在湖南省人民医院住院的173例行PICC置管的肿瘤患者,分为对照组和居家组,其中对照组92例,居家组81例。对照组予常规延续护理服务,居家组通过关注互联网微信公众号构建的居家照护平台予以包括护士上门导管维护、个性化健康教育等延续护理服务。比较两组患者自置管至拔管期间导管维护例数和频次、患者PICC日常维护知识水平及PICC导管相关并发症发生率。结果居家组总体并发症发生率低于对照组,差异有统计学意义(χ2=5.210,P<0.05);居家组导管维护缺失例数和频次低于对照组,PICC家庭日常维护知识水平高于对照组,差异有统计学意义(P<0.05)。结论基于互联网+居家照护平台的PICC肿瘤患者延续护理服务具有可行性、实用性,患者可以获得安全、同质、连续的居家PICC延续护理服务,值得推广。 展开更多
关键词 肿瘤 外周中心静脉导管 延续护理 互联网 居家照护平台
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2018 Chinese Pediatric Cardiology Society(CPCS) guideline for diagnosis and treatment of syncope in children and adolescents 被引量:57
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作者 Cheng Wang Yaqi Li +86 位作者 Ying Liao Hong Tian Min Huang Xiangyu Dong Lin shi Jinghui Sun Hongfang Jin Junbao Du Jindou An Jie Chen Mingwu Chen Qi Chen Sun Chen Yonghong Chen Zhi Chen Adolphus Kai-tung Chau Junbao Du Zhongdong Du Junkai Duan Hongyu Duan Xiangyu Dong Lin Feng Lijun Fu Fangqi Gong Yonghao Gui Ling Han Zhenhui Han Bing He Zhixu He Xiufen Hu Yimin Hua Guoying Huang Min Huang Ping Huang Yujuan Huang Hongfang Jin Mei Jin Bo Li Fen Li Tao Li Xiaohui Li Xiaoyan Liu Yan Li Haitao Lv Tiewei Lv Zipu Li Luyi Ma Silin Pan Yusheng Pang Hua Peng Yuming qin Jie Shen Lin shi Kun Sun Jinghui Sun Hong Tian Jie Tian Cheng Wang Hong Wang Lei Wang Jinju Wang Wendi Wang Yuli Wang Rongzhou Wu Tianhe Xia Yanyan Xiao Chunhong Xie Yanlin Xing Zhenyu Xiong Baoyuan Xu Yi Xu Hui Yan shiwei Yang Qijian Yi Xia Yu Xianyi Yu Yue Yuan Hongyan Zhang Huili Zhang Li Zhang qingyou Zhang Xi Zhang Yanmin Zhang Zhiwei Zhang Cuifen Zhao Bin Zhou Hua Zhu 《Science Bulletin》 SCIE EI CAS CSCD 2018年第23期1558-1564,共7页
Syncope belongs to the transient loss of consciousness(TLOC), characterized by a rapid onset, short duration, and spontaneous complete recovery. It is common in children and adolescents, accounting for 1% to 2% of eme... Syncope belongs to the transient loss of consciousness(TLOC), characterized by a rapid onset, short duration, and spontaneous complete recovery. It is common in children and adolescents, accounting for 1% to 2% of emergency department visits.Recurrent syncope can seriously affect children's physical and mental health, learning ability and quality of life and sometimes cardiac syncope even poses a risk of sudden death. The present guideline for the diagnosis and treatment of syncope in children and adolescents was developed for guiding a better clinical management of pediatric syncope. Based on the globally recent development and the evidence-based data in China, 2018 Chinese Pediatric Cardiology Society(CPCS) guideline for diagnosis and treatment of syncope in children and adolescents was jointly prepared by the Pediatric Cardiology Society, Chinese Pediatric Society, Chinese Medical Association(CMA)/Committee on Pediatric Syncope, Pediatricians Branch, Chinese Medical Doctor Association(CMDA)/Committee on Pediatric Cardiology, Chinese College of Cardiovascular Physicians, Chinese Medical Doctor Association(CMDA)/Pediatric Cardiology Society, Beijing Pediatric Society, Beijing Medical Association(BMA). The present guideline includes the underlying diseases of syncope in children and adolescents, the diagnostic procedures, methodology and clinical significance of standing test and headup tilt test, the clinical diagnosis vasovagal syncope, postural orthostatic tachycardia syndrome, orthostatic hypotension and orthostatic hypertension, and the treatment of syncope as well as follow-up. 展开更多
关键词 CPCS CHILDREN ADOLESCENT SYNCOPE
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Progress in additive manufacturing on new materials: A review 被引量:57
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作者 Neng Li Shuai Huang +5 位作者 Guodong Zhang Renyao qin Wei Liu Huaping Xiong Gongqi shi Jon Blackburn 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2019年第2期242-269,共28页
Recent efforts and advances in additive manufacturing(AM) on different types of new materials are presented and reviewed. Special attention is paid to the material design of cladding layers, the choice of feedstock ma... Recent efforts and advances in additive manufacturing(AM) on different types of new materials are presented and reviewed. Special attention is paid to the material design of cladding layers, the choice of feedstock materials, the metallurgical behavior and synthesis principle during the AM process, and the resulted microstructures and properties, as well as the relationship between these factors. Thereafter,the trend of development in the future is forecasted, including: Effects of the particles size and size distribution of powders; Approaches for producing fine microstructures; Opportunities for creating new materials by AM; Wide applications in reconditioning of damaged components; Challenges for deep understanding and applications of the AMed new materials. The idea of "Develop Materials" or "Create Materials" by AM is highlighted, but a series of scientific, technological and engineering problems remain to be solved in future. 展开更多
关键词 ADDITIVE manufacturing FEEDSTOCK material Laser and ELECTRON beam MELTING Microstructure PROPERTY
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Effects of different resuscitation fluid on severe acute pancreatitis 被引量:57
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作者 Gang Zhao Jun-Gang Zhang +10 位作者 He-Shui Wu Jin Tao Qi qin shi-Chang Deng Yang Liu Lin Liu Bo Wang Kui Tian Xiang Li Shuai Zhu Chun-You Wang 《World Journal of Gastroenterology》 SCIE CAS 2013年第13期2044-2052,共9页
AIM: To compare effects of different resuscitation fluid on microcirculation, inflammation, intestinal barrier and clinical results in severe acute pancreatitis (SAP). METHODS: One hundred and twenty patients with SAP... AIM: To compare effects of different resuscitation fluid on microcirculation, inflammation, intestinal barrier and clinical results in severe acute pancreatitis (SAP). METHODS: One hundred and twenty patients with SAP were enrolled at the Pancreatic Disease Institute between January 2007 and March 2010. The patients were randomly treated with normal saline (NS group), combination of normal saline and hydroxyethyl starch (HES) (SH group), combination of normal saline, hydroxyethyl starch and glutamine (SHG group) in resuscitation. The ratio of normal saline to HES in the SH and SHG groups was 3:1. The glutamine (20% glutamine dipeptide, 100 mL/d) was supplemented into the resuscitation liquid in the SHG group. Complications and outcomes including respiratory and abdominal infection, sepsis, abdominal hemorrhage, intra-abdominal hypertension, abdominal compartment syndrome (ACS), renal failure, acute respiratory distress syndrome (ARDS), multiple organ dysfunction syndrome (MODS), operation intervention, length of intensive care unit stay, length of hospital stay, and mortality at 60 d were compared. Moreover, blood oxygen saturation (SpO 2 ), gastric intramucosal pH value (pHi), intra-abdominal pressure (IAP), inflammation cytokines, urine lactulose/mannitol (L/M) ratio, and serum endotoxin were investigated to evaluate the inflammatory reaction and gut barrier. RESULTS: Compared to the NS group, patients in the SH and SHG groups accessed the endpoint more quickly (3.9 ± 0.23 d and 4.1 ± 0.21 d vs 5.8 ± 0.25 d, P < 0.05) with less fluid volume (67.26 ± 28.53 mL/kg/d, 61.79 ± 27.61 mL/kg per day vs 85.23 ± 21.27 mL/kg per day, P < 0.05). Compared to the NS group, incidence of renal dysfunction, ARDS, MODS and ACS in the SH and SHG groups was obviously lower. Furthermore, incidence of respiratory and abdominal infection was significantly decreased in the SH and SHG groups, while no significant difference in sepsis was seen. Moreover, less operation time was needed in the SH and SHG group than the NS group, but 展开更多
关键词 MICROCIRCULATION INTESTINAL barrier INFLAMMATORY reaction INTRA-ABDOMINAL hypertension CAPILLARY leakage syndrome
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Why Lake Taihu continues to be plagued with cyanobacterial blooms through 10 years(2007–2017) efforts 被引量:56
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作者 Boqiang qin Hans W.Paerl +7 位作者 Justin D.Brookes Jianguo Liu Erik Jeppesen Guangwei Zhu Yunlin Zhang Hai Xu Kun shi Jianming Deng 《Science Bulletin》 SCIE EI CAS CSCD 2019年第6期354-356,共3页
With the expansion of urban, industry, and agriculture after World War II, eutrophication firstly emerged as a major water quality threat in small water bodies [1]. As the increasing magnitudes and scales of nutrient ... With the expansion of urban, industry, and agriculture after World War II, eutrophication firstly emerged as a major water quality threat in small water bodies [1]. As the increasing magnitudes and scales of nutrient pollution and habitat alteration, many of the world's large lakes exhibit symptoms of eutrophication, e.g., toxic cyanobacterial blooms, deoxygenation, and habitat loss. 展开更多
关键词 With the expansion INCREASING MAGNITUDES HABITAT loss
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喜马拉雅琼嘉岗超大型伟晶岩锂矿的形成时代、源区特征及分异特征 被引量:54
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作者 赵俊兴 何畅通 +5 位作者 秦克章 施睿哲 刘小驰 胡方泱 余可龙 孙政浩 《岩石学报》 SCIE EI CAS CSCD 北大核心 2021年第11期3325-3347,共23页
喜马拉雅新生代淡色花岗岩带是近年来提出的与高度结晶分异、异地深成淡色花岗岩有关的稀有金属战略远景区,目前其金属组合以铍-铌-钽(-锡-钨)为主。秦克章等(2021a)报道了在高喜马拉雅带珠峰地区发现的琼嘉岗锂矿,是喜马拉雅首例具有... 喜马拉雅新生代淡色花岗岩带是近年来提出的与高度结晶分异、异地深成淡色花岗岩有关的稀有金属战略远景区,目前其金属组合以铍-铌-钽(-锡-钨)为主。秦克章等(2021a)报道了在高喜马拉雅带珠峰地区发现的琼嘉岗锂矿,是喜马拉雅首例具有工业价值的伟晶岩型锂矿。本次研究重点揭示喜马拉雅琼嘉岗伟晶岩型锂矿的成矿特征、形成时代和源区特征。琼嘉岗矿区矿石矿物主要为锂辉石、铌铁矿-铌锰矿、少量锡石和绿柱石,特征性长柱状锂辉石主要产于块体微斜长石+锂辉石带和分层细晶岩带内。琼嘉岗锂辉石伟晶岩各结构分带的K/Rb含量较为相似,锂含量从边部细粒钠长石带(~100×10^(-6))到分层细晶岩带(~1000×10^(-6)),再到块体微斜长石+锂辉石带(>3000×10^(-6))逐渐升高,而Cs含量逐渐降低。独居石和铌钽铁矿族矿物LA-ICPMS定年结果显示,琼嘉岗锂辉石伟晶岩形成于新喜马拉雅阶段早期(25~24Ma),与高喜马拉雅地区淡色花岗岩时代相近。矿物化学和独居石Nd同位素结果显示该稀有金属伟晶岩结晶于高度演化的花岗伟晶岩熔体,源区特征与高喜马拉雅结晶岩系一致。本研究所揭示的琼嘉岗成矿特征、形成时代和源区特征将为高喜马拉雅其它地区找寻大型花岗伟晶岩型锂矿提供重要借鉴意义。 展开更多
关键词 琼嘉岗锂矿 伟晶岩结构与成分 独居石和铌钽铁矿U-Pb定年 源区示踪 喜马拉雅淡色花岗岩带区域成矿
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深刺廉泉与翳风穴对脑卒中后吞咽障碍的影响 被引量:53
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作者 覃亮 张选平 +3 位作者 杨信才 崔彩虹 石晶 贾春生 《针刺研究》 CAS CSCD 北大核心 2019年第2期144-147,共4页
目的:观察针刺对脑卒中后吞咽障碍的影响。方法:将104例脑卒中后吞咽障碍患者随机分为试验组与对照组,每组52例。对照组患者给予常规吞咽康复训练,每日1次,每周6d,连续治疗4周。试验组患者在对照组基础上配合深刺廉泉穴与翳风穴结合常... 目的:观察针刺对脑卒中后吞咽障碍的影响。方法:将104例脑卒中后吞咽障碍患者随机分为试验组与对照组,每组52例。对照组患者给予常规吞咽康复训练,每日1次,每周6d,连续治疗4周。试验组患者在对照组基础上配合深刺廉泉穴与翳风穴结合常规针刺治疗,每日1次,每周6d,连续治疗4周。治疗前后对两组患者进行标准吞咽功能评定法(SSA)、洼田饮水试验检测,并进行临床疗效及不良反应情况综合评价。结果:与治疗前比较,两组治疗后SSA评分均降低(P<0.05);试验组治疗后SSA评分明显低于对照组(P<0.05)。治疗后,两组患者洼田饮水试验吞咽能力较治疗前均有提高(P<0.05);试验组治疗后洼田饮水试验吞咽能力提高程度优于对照组(P<0.05)。治疗后试验组(46/52,88.46%)综合疗效的总有效率高于对照组(32/52,61.54%,P<0.05)。试验组不良反应总发生率为9.62%(5/52),对照组不良反应总发生率为11.54%(6/52),两组差异无统计学意义(P>0.05)。结论:深刺廉泉穴与翳风穴基础上结合常规针刺治疗可以改善脑卒中后吞咽障碍患者的舌咽功能,协调吞咽肌肉,重建吞咽功能,不良反应发生较少。 展开更多
关键词 针刺 脑卒中 吞咽障碍 廉泉穴 翳风穴 常规吞咽训练
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适用于中国人群的血管性痴呆筛查和诊断框架 被引量:52
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作者 田金洲 解恒革 +7 位作者 秦斌 樊东升 卢涛 时晶 倪敬年 王鲁宁 王荫华 中国老年保健协会阿尔茨海默病分会研究小组 《中华内科杂志》 CAS CSCD 北大核心 2019年第1期10-16,共7页
针对我国认知筛查标准化体系缺乏和脑血管病影像学特征认定存在争议等问题,该研究小组利用神经心理学、神经影像学和临床神经病学等知识和技术,对血管性痴呆诊断涉及的记忆、语言、视空间、执行、功能和MRI脑血管病证据等检测技术及其... 针对我国认知筛查标准化体系缺乏和脑血管病影像学特征认定存在争议等问题,该研究小组利用神经心理学、神经影像学和临床神经病学等知识和技术,对血管性痴呆诊断涉及的记忆、语言、视空间、执行、功能和MRI脑血管病证据等检测技术及其最佳阈值和诊断价值进行了系统研究,并通过系统综述和共识会议等形式,将原则性的诊断指南与操作性的筛查方案相结合,构建了适用于中国人群的血管性痴呆筛查和诊断框架。该框架以病史和临床评估的客观证据为核心特征,以与临床一致的脑血管病影像学证据为支持特征,并排除痴呆的其他病因或伴随病变,适用于我国临床环境,对血管性痴呆的早发现、早诊断、早治疗具有重要意义。 展开更多
关键词 痴呆 血管性 筛查和诊断 框架
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复发性流产的免疫学因素研究进展 被引量:48
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作者 秦诗 高玉平 《中华生殖与避孕杂志》 CAS CSCD 北大核心 2018年第2期165-169,共5页
复发性流产(recurrent spontaneous abortion,RSA)是指连续≥2次的自然流产,且常发生于同一妊娠月份,临床发病率约1%~5%。除美国妇产科医师协会(ACOG)、皇家妇产科医师学会(RCOG)已明确提出的病因如染色体异常、母体生殖道异常、母体内... 复发性流产(recurrent spontaneous abortion,RSA)是指连续≥2次的自然流产,且常发生于同一妊娠月份,临床发病率约1%~5%。除美国妇产科医师协会(ACOG)、皇家妇产科医师学会(RCOG)已明确提出的病因如染色体异常、母体生殖道异常、母体内分泌异常、生殖道感染、血栓形成倾向等,约80%与免疫因素相关。近年来研究者根据免疫学发病机制将RSA分为自身免疫型和同种免疫型两大类,前者可能由于自身抗体针对内皮细胞、滋养细胞及种植前胚胎导致妊娠失败,后者则可能与母-胎界面免疫失衡有关。本文将分别从这2个方面就RSA免疫学发病机制进行综述。 展开更多
关键词 复发性流产(RSA) 免疫 病因 诊断
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Combined detections of interleukin 27, interferon-γ, and adenosine deaminase in pleural effusion for diagnosis of tuberculous pleurisy 被引量:42
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作者 WU Yan-bin YE Zhi-jian +3 位作者 qin Sou-ming WU Cong CHEN Yi-qiang shi Huan-zhong 《Chinese Medical Journal》 SCIE CAS CSCD 2013年第17期3215-3221,共7页
Background Previous studies reported interleukin-27 (IL-27), interferon-y (IFN-γ), or adenosine deaminase (ADA) alone plays a helpful role in diagnosing tuberculous pleural effusion (TPE). The present study a... Background Previous studies reported interleukin-27 (IL-27), interferon-y (IFN-γ), or adenosine deaminase (ADA) alone plays a helpful role in diagnosing tuberculous pleural effusion (TPE). The present study aims at comparing the diagnostic accuracy of pleural IL-27, IFN-γ, and ADA, and investigate the diagnostic accuracy of the combination of IL-27, IFN-γ, or/ and ADA for differentiating TPE from pleural effusions with the other etiologies. Methods The concentrations of IL-27, IFN-γ and ADA were simultaneously determined in pleural fluids and sera from 40 patients with TPE; 26 with malignant pleural effusion, seven with infectious pleural effusion, and eight with transudative pleural effusion by enzyme linked immunosorbent assay and colorimetric method. The corresponding biochemical indexs were also simultaneously determined. Results The concentrations of pleural IL-27 and IFN-γ in the tuberculous group were significantly higher than those in the malignant, infectious, and transudative groups. The concentrations of ADA in TPE were significantly higher than those in MPE or transudative effusions, while much lower than those in infectious effusions. Among these three biomarkers, IL- 27 was the most effective for TPE diagnosis, with the cut off value of 900.8 ng/L. IL-27 had a high sensitivity of 95% and specificity of 97.6% for differential diagnosis of TPE from non-TPEs. Combinations of IL-27, IFN-γ and ADA measurements further increased the sensitivity or specificity up to 100%. Conclusions Compared to non-TPEs, IL-27, IFN-γ and ADA all simultaneously increased in TPE; and among these three rapid detection methods, IL-27 appeared to be the best for distinguishing tuberculous from non-TPEs, especially from MPE. Combinations of the three markers (IL-27, IFN-γ and ADA) yielded the highest sensitivity and specificity. These findings suggest that the applications of a new biomarker, IL-27, alone or with IFN-γ and ADA, may contribute to more efficient diagnosis strategies in the management 展开更多
关键词 adenosine deaminase INTERFERON-Γ interleukin 27 tuberculous pleurisy
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西安市城市化对景观格局及生态系统服务价值的影响 被引量:40
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作者 秦艳丽 时鹏 +5 位作者 何文虹 霍春平 李鹏 李占斌 杨殊桐 冯朝红 《生态学报》 CAS CSCD 北大核心 2020年第22期8239-8250,共12页
我国处于城市化高度发展阶段,截止2018年全国城市化率达到59.58%。城市的快速扩张,显著改变了区域景观格局,深刻影响城市生态系统的供给、调节、文化、支持等服务功能。近30年来,西安市城市用地扩张554.23 km^(2),基于西安市景观格局变... 我国处于城市化高度发展阶段,截止2018年全国城市化率达到59.58%。城市的快速扩张,显著改变了区域景观格局,深刻影响城市生态系统的供给、调节、文化、支持等服务功能。近30年来,西安市城市用地扩张554.23 km^(2),基于西安市景观格局变化分析,利用同心缓冲区探讨城乡梯度内景观指数与生态系统服务价值的特征及其相互关系,揭示城市发展对城市生态系统的影响。结果表明,1980—2015年西安市各景观类型面积发生明显变化,耕地、草地面积逐渐减少,建设用地面积波动增加,主要来源于优势景观耕地的转化。景观破碎度最高的区域主要分布在距市中心10 km左右的城乡结合部,斑块密度、边缘密度、景观分割度最高,且随城市扩张,拐点距离逐渐增加。林地和耕地是提供生态系统服务的主要土地类型,西安地区总生态服务价值减少了9.56亿元,耕地减少最多(6.83亿元),沿城乡梯度,总生态系统服务价值均值呈现从市中心到农村递增的趋势,土壤保持的生态服务价值增长最快;沿时间梯度上,生态服务价值均值呈现逐年减少现象;从景观格局对生态服务价值影响分析得知,多样性指数与各类型生态系统服务价值之间存在显著的相关关系,最大斑块指数与不同类型的服务价值呈高度负相关。城市建设使得区域的生态系统服务价值降低,在城市发展中需要科学规划用地、合理布设景观格局,提高生态环境质量,达到城市生态宜居的目的。 展开更多
关键词 城市化 景观格局 生态系统服务价值 城乡梯度带
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数据挖掘在护理不良事件管理中的应用进展 被引量:39
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作者 丁四清 陆晶 +4 位作者 秦春香 盛江明 王璐 石双姣 李雨潇 《中华护理杂志》 CSCD 北大核心 2019年第6期873-877,共5页
从不良事件上报、监测和预警3个方面综述了基于数据挖掘的护理不良事件管理研究,旨在为护理不良事件管理和护理实践提供参考。
关键词 数据挖掘 不良事件 护理管理研究 患者安全 综述
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茉莉花茶特征香气成分研究 被引量:37
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作者 安会敏 欧行畅 +6 位作者 熊一帆 张杨波 李娟 李勤 李骞 李适 黄建安 《茶叶科学》 CAS CSCD 北大核心 2020年第2期225-237,共13页
茉莉花茶是我国特有的再加工茶,香气是决定茉莉花茶品质的最主要因素。本研究采用顶空固相微萃取(HS-SPME)和气相色谱-质谱联用(GC-MS)技术,对绿茶素坯和茉莉花茶的挥发性成分定性定量,通过正交偏最小二乘判别分析法(Orthogonal project... 茉莉花茶是我国特有的再加工茶,香气是决定茉莉花茶品质的最主要因素。本研究采用顶空固相微萃取(HS-SPME)和气相色谱-质谱联用(GC-MS)技术,对绿茶素坯和茉莉花茶的挥发性成分定性定量,通过正交偏最小二乘判别分析法(Orthogonal projections to latent structures discriminant analysis,OPLS-DA)、香气活度值法(Odor activity value,OAV)筛选茉莉花茶的特征香气成分,并探究其对花茶品质的调控作用。结果表明,绿茶素坯与茉莉花茶中共鉴定出70种挥发性成分,其中茉莉花茶的特征香气成分有13种,分别是3-己烯-1-醇、苯甲醇、芳樟醇、苯乙醇、乙酸叶醇酯、苯甲酸甲酯、乙酸苄酯、水杨酸甲酯、顺式-3-己烯基异戊酸酯、2-氨基苯甲酸甲酯、顺式-3-己烯基苯甲酸酯、吲哚和α-法呢烯;苯乙醇与茉莉花茶品质相关性较低,其余12种特征香气成分与茉莉花茶品质相关性较强(r≥0.84)。该研究结果为茉莉花茶品质的评定、调控和提升提供了理论依据。 展开更多
关键词 茉莉花茶 特征香气成分 花茶品质
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