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急性缺血性卒中患者早期处理指南:美国心脏协会/美国卒中协会对医疗专业人员的指南(续前) 被引量:988
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作者 Edward C. Jauch Jeffrey L. Saver +17 位作者 Harold P. Adams Askiel Bruno J.J. (Buddy) Connors Bart M. Demaerschalk Pooja Khatri Paul W. McMullan Adnan i. Qureshi Kenneth Rosenfield Phillip A. Scott Debbie R. Summers David Z. Wang Max Wintermark Howard Yonas 李海峰(译) 岳耀先(译) 王琦(译) 张贤军(译) 丁晓君(译) 《国际脑血管病杂志》 北大核心 2013年第8期564-605,共42页
7静脉溶栓 7.1静脉rtPA 急性卒中的静脉溶栓治疗现已得到普遍接受。美国FDA于1996年批准静脉应用rtPA,部分基于NINDSrtPA卒中试验结果。
关键词 美国心脏协会 卒中协会 急性缺血性卒中 医疗专业 早期处理 静脉溶栓治疗 指南 患者
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急性缺血性卒中静脉阿替普酶溶栓治疗的纳入和排除标准的科学依据美国心脏协会/美国卒中协会对医疗卫生专业人员发布的声明(续前) 被引量:103
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作者 Dawn O. Kleindorfer Opeolu M. Adeoye +18 位作者 Andrew M. Demchuk Jennifer E. Fugate James C. Grotta Alexander A. Khalessi Elad i. Levy Yuko Y. Palesch Shyam Prabhakaran Gustavo Saposnik Jeffrey L. Saver Eric E. Smith 高圆圆 顾雨铖 徐欣 徐曼曼 张佳慧 李韶雅 冒萧萧 陈歆 徐运 《国际脑血管病杂志》 2016年第5期385-406,共22页
19 颅内出血史 根据最初的 FDA 标签和2013年AHA/ASA指南,颅内出血史是静脉阿替普酶治疗缺血性卒中的一项额外禁忌证或排除标准。最近修订后的标签仅将近期 ICH 列为一项警告,并且在禁忌证中删除了ICH史。与前面讨论的静脉阿替普酶治... 19 颅内出血史 根据最初的 FDA 标签和2013年AHA/ASA指南,颅内出血史是静脉阿替普酶治疗缺血性卒中的一项额外禁忌证或排除标准。最近修订后的标签仅将近期 ICH 列为一项警告,并且在禁忌证中删除了ICH史。与前面讨论的静脉阿替普酶治疗排除标准相似,文献回顾仅在大样本回顾性研究中发现了少量这类病例。缺乏相关数据可能是修订后的FDA 标签不再将 ICH 史作为禁忌证而仅将近期ICH 列为一项警告的原因。在这种情况下,FDA 如何定义“近期”一词尚不清楚。有趣的是,对在静脉阿替普酶治疗前通过 MRI 检测脑微出血( cerebral microbleed, CMBs)存在情况进行的研究可为这个卒中亚组患者提供更多的见解。从病理生理学角度,这种微出血的原因尚不清楚,可能反映再灌注损伤或脑血管自动调节功能破坏。因此,在静脉阿替普酶治疗后出现这些损害可能没有意义或是人为信号。 展开更多
关键词 急性缺血性卒中 阿替普酶 溶栓治疗 美国心脏协会 排除标准 卫生专业人员 静脉 卒中协会
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地震前亚失稳应力状态的识别--以5°拐折断层变形温度场演化的实验为例 被引量:86
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作者 马瑾 S i SHERMAN 郭彦双 《中国科学:地球科学》 CSCD 北大核心 2012年第5期633-645,共13页
识别亚失稳应力状态,研究其力学机理及与之相关物理场的演化特性,对于分析地震潜在危险性以及危险时段具有十分重要的理论意义和应用意义.在实验室,标本进入亚失稳态的标志是应力的加速释放.能否利用实验结果去鉴别自然条件下的地震?一... 识别亚失稳应力状态,研究其力学机理及与之相关物理场的演化特性,对于分析地震潜在危险性以及危险时段具有十分重要的理论意义和应用意义.在实验室,标本进入亚失稳态的标志是应力的加速释放.能否利用实验结果去鉴别自然条件下的地震?一个台站的观测数据仅代表该台站的应力状况,如何通过众多台站的观测数据了解区域应力状态是识别亚失稳态的关键问题.本文以拐折断层一次粘滑事件中不同变形阶段温度场的演化为例,试图寻找物理量在进入亚失稳状态的响应特征.文中分别讨论了应力积累阶段、失稳前应力-时间过程中偏离线性阶段、峰值后亚失稳阶段、失稳阶段和失稳后阶段的特点.研究结果显示断层的失稳错动是由断层各个部位独立活动向协同化活动的转化过程.失稳代表协同作用的完成.偏离线性阶段是应力释放的开始,也是协同作用的开始.在亚失稳阶段应力释放已占据优势,协同作用趋于完成.分析区域整体应力状态不能从单个台站出发,而是要从变形场的整体演化出发. 展开更多
关键词 地震危险性 应力状态 亚失稳态 温度场演化 协同作用 拐折断层
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Recent advances in gastric cancer early diagnosis 被引量:84
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作者 Laura Necula Lilia Matei +6 位作者 Denisa Dragu Ana i Neagu Cristina Mambet Saviana Nedeianu Coralia Bleotu Carmen C Diaconu Mihaela Chivu-Economescu 《World Journal of Gastroenterology》 SCIE CAS 2019年第17期2029-2044,共16页
Gastric cancer(GC) remains an important cause of cancer death worldwide with a high mortality rate due to the fact that the majority of GC cases are diagnosed at an advanced stage when the prognosis is poor and the tr... Gastric cancer(GC) remains an important cause of cancer death worldwide with a high mortality rate due to the fact that the majority of GC cases are diagnosed at an advanced stage when the prognosis is poor and the treatment options are limited. Unfortunately, the existing circulating biomarkers for GC diagnosis and prognosis display low sensitivity and specificity and the GC diagnosis is based only on the invasive procedures such as upper digestive endoscopy. There is a huge need for less invasive or non-invasive tests but also highly specific biomarkers in case of GC. Body fluids such as peripheral blood, urine or saliva,stomach wash/gastric juice could be a source of specific biomarkers, providing important data for screening and diagnosis in GC. This review summarized the recently discovered circulating molecules such as microRNAs, long non-coding RNAs, circular RNAs, which hold the promise to develop new strategies for early diagnosis of GC. 展开更多
关键词 Biomarkers GASTRIC cancer Early diagnosis Genetic and EPIGENETIC alterations CIRCULATING MOLECULES
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卫星导航几何因子的分析和仿真 被引量:67
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作者 丛丽 Ahmed i Abidat 谈展中 《电子学报》 EI CAS CSCD 北大核心 2006年第12期2204-2208,共5页
根据卫星导航几何因子GDOP在具体课题中的应用,从五个主要方面对其进行了研究,可知不同星座配置参数对不同纬度地区GDOP会产生影响;坐标转换时GDOP、PDOP和TDOP不变,HDOP、VDOP变化;GDOP随卫星数目增加单调递减,但递减幅度变小;卫星对G... 根据卫星导航几何因子GDOP在具体课题中的应用,从五个主要方面对其进行了研究,可知不同星座配置参数对不同纬度地区GDOP会产生影响;坐标转换时GDOP、PDOP和TDOP不变,HDOP、VDOP变化;GDOP随卫星数目增加单调递减,但递减幅度变小;卫星对GDOP贡献越大,其故障产生的定位误差越大;使用加权GDOP可有效的减小定位误差. 展开更多
关键词 卫星导航 DOP 星座配置参数 定位精度 加权GDOP
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金厂沟梁-二道沟金矿田内花岗岩类侵入体锆石的离子探针U-Pb年代学及意义 被引量:71
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作者 苗来成 范蔚茗 +3 位作者 翟明国 Qiu Y M McNaughton N J Groves D i 《岩石学报》 SCIE EI CAS CSCD 北大核心 2003年第1期71-80,共10页
金厂沟梁-二道沟金矿田内花岗岩类侵入体SHRIMP锆石U-Ph定年结果表明,该区中生代以来到少经历了三次中酸性岩浆侵入作用,它们分别以西台子二长花岗岩、娄上含辉石石英闪长岩和西对面沟花岗闪长岩及闪长玢岩脉在218±4Ma(印支期)、16... 金厂沟梁-二道沟金矿田内花岗岩类侵入体SHRIMP锆石U-Ph定年结果表明,该区中生代以来到少经历了三次中酸性岩浆侵入作用,它们分别以西台子二长花岗岩、娄上含辉石石英闪长岩和西对面沟花岗闪长岩及闪长玢岩脉在218±4Ma(印支期)、161±1Ma(燕山早期)和126±1Ma(燕山晚期)的侵位为标志。花岗岩类的地球化学资料表明,这些花岗岩类侵入体形成与造山作用有关,为造山后或陆内拉张作用的产物。二道沟矿区成矿前或成矿期闪长玢岩脉的年龄126±1Ma限定了该区金矿化的最大年龄;结合前人有关年代学资料,认为本区金矿化应发生在126~118Ma。这说明金厂沟梁-二道沟金矿田的金矿床与我国胶东、小秦岭和辽东等地区的金矿床是同时形成的,再次证明燕山晚期是中国最重要而广泛的金成矿期。此外,在这些主要的金矿区内,金矿化时间上均具有与各自区内最晚一次花岗质岩浆作用同时或稍晚的特征,这可能指示金矿床是造山作用或区域构造-岩浆演化最晚期的产物。 展开更多
关键词 金矿田 离子探针 花岗岩类侵入本 锆石 SHRIMP 年代学 成矿时代 造山作用
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帕博利珠单抗单用或与放疗联用治疗转移性非小细胞肺癌:两个随机试验的汇总分析 被引量:70
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作者 陈大卫(翻译) 于金明(校对) +18 位作者 Willemijn S M E Theelen Vivek Verma Brian P Hobbs Heike M U Peulen Joachim G J V Aerts idris Bahce Anna Larissa N Niemeijer Joe Y Chang Patricia M de Groot Quynh-Nhu Nguyen Nathan i Comeaux George R Simon Ferdinandos Skoulidis Steven H Lin Kewen He Roshal Patel John Heymach Paul Baas James W Welsh 《中华肿瘤防治杂志》 CAS 北大核心 2021年第24期1841-1850,共10页
背景放疗可以提高整个机体对免疫治疗的应答。在Ⅱ期PEMBRO-RT研究和Ⅰ/Ⅱ期MDACC研究中,患有转移性非小细胞肺癌(NSCLC)的患者被随机分配入组,接受免疫治疗(帕博利珠单抗)+放疗联合疗法,或免疫治疗单一疗法。当上述2个研究单独分析时,... 背景放疗可以提高整个机体对免疫治疗的应答。在Ⅱ期PEMBRO-RT研究和Ⅰ/Ⅱ期MDACC研究中,患有转移性非小细胞肺癌(NSCLC)的患者被随机分配入组,接受免疫治疗(帕博利珠单抗)+放疗联合疗法,或免疫治疗单一疗法。当上述2个研究单独分析时,联合疗法组显示出潜在获益。由于每个研究的样本量较小,缓解率和结局并未显示出统计学意义,然而却有显著的临床获益。因此,本研究进行汇总分析,来判断放疗是否会改善转移性NSCLC患者的免疫治疗应答。方法PEMBRO-RT和MDACC研究纳入标准:患者年龄≥18岁,患有转移性NSCLC,且有≥1处未经放疗照射的病灶,以便进行射野外应答监测。PEMBRO-RT研究纳入曾接受过化疗患者,MDACC研究纳入曾接受过治疗或新诊断患者。2个研究中的患者均未接受过免疫治疗。在PEMBRO-RT研究中患者被等比例随机分配入组,并根据吸烟状态进行分层(分为<10年组和≥10年组)。MDACC研究的患者根据放疗计划可行性被等比例随机分配入2个受试组。由于联合治疗组的干预本质,每个研究中的放疗均不适用盲法。在2个研究中,不论是否进行放疗,均静脉滴入帕博利珠单抗(每3周200 mg)。在PEMBRO-RT研究中,在放疗(24 Gy 3次分割照射)结束后1周给予第1剂帕博利珠单抗。在MDACC研究中,在第1次放疗(50 Gy 4次分割照射或45 Gy 15次分割照射)同时给予帕博利珠单抗。仅检测未经照射病灶的应答。本研究的终点为最佳射野外(远隔)应答率(ARR)、最佳射野外疾病控制率(ACR)、12周时ARR、12周时ACR、无进展生存期(PFS)和总生存期(OS)。2个研究的意向治疗(ITT)人群均纳入分析。PEMBRO-RT研究(NCT02492568)和MDACC研究(NCT02444741)均在ClinicalTrials.gov上注册。发现纳入148例患者,76例接受帕博利珠单抗治疗,72例接受帕博利珠单抗+放疗治疗。所有患者随访时间中位数为33个月[四分位距(IQR):32.4~33.6]。148例� 展开更多
关键词 帕博利珠单抗 非小细胞肺癌 放疗 汇总分析
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温度对美拉德反应的研究(英文) 被引量:54
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作者 吴少雄 M A J S van Boeke +2 位作者 S i F S Martins 郭祀远 李琳 《食品科学》 EI CAS CSCD 北大核心 2005年第7期63-66,共4页
本文报道了反应温度对以d-葡萄糖和l-甘氨酸水溶液模式体系美拉德反应的影响。研究了在不同反应温度(80、100、120℃)和不同反应时间下,体系中糖和氨基酸的降解程度,反应中间体:阿利德诺和有机酸的累积程度,类黑素的形成及pH变化程度。... 本文报道了反应温度对以d-葡萄糖和l-甘氨酸水溶液模式体系美拉德反应的影响。研究了在不同反应温度(80、100、120℃)和不同反应时间下,体系中糖和氨基酸的降解程度,反应中间体:阿利德诺和有机酸的累积程度,类黑素的形成及pH变化程度。研究结果表明:随着反应温度和反应时间的增加,反应速率加快。 展开更多
关键词 美拉德反应 葡萄糖 甘氨酸 温度
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Diabetic cardiomyopathy:Pathophysiology,diagnostic evaluation and management 被引量:61
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作者 Joseph M Pappachan George i Varughese +1 位作者 Rajagopalan Sriraman Ganesan Arunagirinathan 《World Journal of Diabetes》 SCIE CAS 2013年第5期177-189,共13页
Diabetes affects every organ in the body and cardiovascular disease accounts for two-thirds of the mortality in the diabetic population.Diabetes-related heart disease occurs in the form of coronary artery disease(CAD)... Diabetes affects every organ in the body and cardiovascular disease accounts for two-thirds of the mortality in the diabetic population.Diabetes-related heart disease occurs in the form of coronary artery disease(CAD),cardiac autonomic neuropathy or diabetic cardiomyopathy(DbCM).The prevalence of cardiac failure is high in the diabetic population and DbCM is a common but underestimated cause of heart failure in diabetes.The pathogenesis of diabetic cardiomyopathy is yet to be clearly defined.Hyperglycemia,dyslipidemia and inflammation are thought to play key roles in the generation of reactive oxygen or nitrogen species which are in turn implicated.The myocardial interstitium undergoes alterations resulting in abnormal contractile function noted in DbCM.In the early stages of the disease diastolic dysfunction is the only abnormality,but systolic dysfunction supervenes in the later stages with impaired left ventricular ejection fraction.Transmitral Doppler echocardiography is usually used to assess diastolic dysfunction,but tissue Doppler Imaging and Cardiac Magnetic Resonance Imaging are being increasingly used recently for early detection of DbCM.The management of DbCM involves improvement in lifestyle,control of glucose and lipid abnormalities,and treatment of hypertension and CAD,if present.The role of vasoactive drugs and antioxidants is being explored.This review discusses the pathophysiology,diagnostic evaluation and management options of DbCM. 展开更多
关键词 DIABETIC CARDIOMYOPATHY Cardiac AUTONOMIC NEUROPATHY Coronary artery disease Heart failure Transmitral Doppler ECHOCARDIOGRAPHY
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川东北地区构造-热演化探讨--来自(U-Th)/He年龄和Ro的约束 被引量:59
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作者 邱楠生 秦建中 +3 位作者 Brent i A Mclnnes 王杰 腾格尔 郑伦举 《高校地质学报》 CAS CSCD 北大核心 2008年第2期223-230,共8页
利用镜质组反射率和磷灰石与锆石的(U-Th)/He年龄一起模拟了川东北地区三叠纪以来的构造-热演化特征。结果表明早三叠世的热流值在51~66mW/m2,自晚三叠世至白垩纪随盆地性质由前陆盆地演化为陆内坳陷盆地,热流缓慢降低直至现今的44.5mW... 利用镜质组反射率和磷灰石与锆石的(U-Th)/He年龄一起模拟了川东北地区三叠纪以来的构造-热演化特征。结果表明早三叠世的热流值在51~66mW/m2,自晚三叠世至白垩纪随盆地性质由前陆盆地演化为陆内坳陷盆地,热流缓慢降低直至现今的44.5mW/m2。但在晚白垩世—古新世时期受燕山晚期构造运动的影响,热流有一个微弱增高的现象。同时,磷灰石和锆石的He年龄揭示了川东北地区大致在晚白垩世期间开始隆升且抬升剥蚀量较大。因此,磷灰石和锆石的(U-Th)/He年龄可以揭示后期详细的冷却历史。 展开更多
关键词 构造-热演化 (U-Th)/He年龄 镜质组反射率 川东北地区
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Spatial Distribution of Heavy Metals in Agricultural Soils of an Industry-Based Peri-Urban Area in Wuxi, China 被引量:50
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作者 ZHAO Yan-Feng SHi Xue-Zheng +5 位作者 HUANG Biao YU Dong-Sheng WANG Hong-Jie SUN Wei-Xia i. OEBOERN K. BLOMBACK 《Pedosphere》 SCIE CAS CSCD 2007年第1期44-51,共8页
In industry-oriented peri-urban areas, the heavy metal accumulation in soils caused by industrialization has become a potential threat. The top soil samples from 27 paddy fields and 75 vegetable fields were collected ... In industry-oriented peri-urban areas, the heavy metal accumulation in soils caused by industrialization has become a potential threat. The top soil samples from 27 paddy fields and 75 vegetable fields were collected from a typical industry- based peri-urban area of about 8 km^2 in Wuxi, China, to study the accumulation and distribution of As, Hg, Cu, Zn, Pb, Cr, and Cd in comparison with heavy metal contents in soils near developed industrial sites (Guangzhou, China; Wallsend Burn of Tyneside, UK; and Osnabrück, Germany). Kriging interpolation was used to determine the metals, spatial distribution. The results showed that most soils, compared to the background values, contained elevated contents of As, Hg, Cu, Zn, and Pb with some having elevated contents of Cd and Cr. Except for less than 10% of the soil samples of Cu, Zn and Cd contents, these heavy metal contents were lower than the soil threshold levels of the Grade Ⅱ criteria for the Chinese environmental quality standard. Probably, because of the scattered distribution and diversity of industries in the study area, spatial distributions of these heavy metals from Kriging interpolation indicated little similarity. Nevertheless, when compared with other areas in the Taihu Lake region, mean contents of Cu, Zn, Pb, and Cd were relatively high in the Wuxi peri-urban area. Additionally, compared to soils in agricultural areas around Guangzhou, Osnabrück, or Wallsend Burn, contents of most heavy metals in soils from this area were lower. 展开更多
关键词 agricultural soil heavy metals peri-urban area spatial distribution
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Prediction of severe acute pancreatitis:Current knowledge and novel insights 被引量:48
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作者 Georgios i Papachristou 《World Journal of Gastroenterology》 SCIE CAS CSCD 2008年第41期6273-6275,共3页
Acute pancreatitis (AP) is a common and potentially lethal acute inflammatory process with a highly variable clinical course. It is still unclear why some patients progress to organ failure and others do not. Physicia... Acute pancreatitis (AP) is a common and potentially lethal acute inflammatory process with a highly variable clinical course. It is still unclear why some patients progress to organ failure and others do not. Physicians, ability to predict which patients will develop severe disease is limited. Routine clinical and laboratory data and multi-factorial clinical scores measured on admission and during the first 48 h of hospitalization are currently the standards of care used to estimate the magnitude of the inflammatory response to injury. Current literature highlights several common environmental, metabolic and genetic factors that increase the risk of AP development and subsequent adverse sequelae. Several cytokines have been found to play a critical role in the pathogenesis of AP by driving the subsequent inflammatory response, to include tumor necrosis factor-α (TNF-α), Interleukin-1 (IL-1), IL-6 and monocyte chemotactic protein-1 (MCP-1). Large, prospective studies are still needed to address these questions by identifying AP risk factors and serum biomarkers of severe disease. 展开更多
关键词 Acute pancreatitis PREDICTION SEVERITY Monocyte chemotactic protein-1
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Environmental issues from coal mining and their solutions 被引量:48
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作者 BiAN, Zhengfu iNYANG, Hilary i +2 位作者 DANiELS, John L OTTO, Frank STRUTHERS, Sue 《Mining Science and Technology》 EI CAS 2010年第2期215-223,共9页
The environmental challenges from coal mining include coal mine accidents,land subsidence,damage to the water environment,mining waste disposal and air pollution.These are either environmental pollution or landscape c... The environmental challenges from coal mining include coal mine accidents,land subsidence,damage to the water environment,mining waste disposal and air pollution.These are either environmental pollution or landscape change.A conceptual framework for solving mine environmental issues is proposed.Clean processes,or remediation measures,are designed to address environmental pollution.Restoration measures are proposed to handle landscape change.The total methane drainage from 56 Chinese high methane concentration coal mines is about 101.94 million cubic meters.Of this methane,19.32 million,35.58 million and 6.97 million cubic meters are utilized for electricity generation,civil fuel supplies and other industrial purposes,respectively.About 39% of the methane is emitted into the atmosphere.The production of coal mining wastes can be decreased 10% by reuse of mining wastes as underground fills,or by using the waste as fuel for power plants or for raw material to make bricks or other infrastructure materials.The proper use of mined land must be decided in terms of local physical and socio-economical conditions.In European countries more than 50% of previously mined lands are reclaimed as forest or grass lands.However,in China more than 70% of the mined lands are reclaimed for agricultural purposes because the large population and a shortage of farmlands make this necessary.Reconstruction of rural communities or native residential improvement is one environmental problem arising from mining.We suggest two ways to reconstruct a farmer's house in China. 展开更多
关键词 mine environment management of mining wastes reuse of mine gas mined land reclamation clean coal mining
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东昆仑南缘早三叠世洪水川组的源区特征:来自碎屑组成、重矿物和岩石地球化学的证据 被引量:47
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作者 闫臻 边千韬 +3 位作者 Oleg A. Korchagin igor i. Pospelov 李继亮 王宗起 《岩石学报》 SCIE EI CAS CSCD 北大核心 2008年第5期1068-1078,共11页
分布于东昆仑南缘的早三叠世洪水川组系一套由砾岩、砂岩、页岩和鲕粒灰岩等浅海相和河流相沉积物构成的弧前盆地沉积组合。砂岩碎屑组成、重矿物组合、岩石地球化学和古水流综合研究结果表明,洪水川组砂岩物源主要来自于北侧的岛弧带,... 分布于东昆仑南缘的早三叠世洪水川组系一套由砾岩、砂岩、页岩和鲕粒灰岩等浅海相和河流相沉积物构成的弧前盆地沉积组合。砂岩碎屑组成、重矿物组合、岩石地球化学和古水流综合研究结果表明,洪水川组砂岩物源主要来自于北侧的岛弧带,同时南侧的阿尼玛卿蛇绿混杂带也为其形成提供了部分物源;源区主要出露长英质岩石、变质岩和硅质岩。 展开更多
关键词 早三叠世 洪水川组 源区背景 东昆仑
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Diagnosis of hepatocellular carcinoma 被引量:44
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作者 Asmaa i Gomaa Shahid A Khan +2 位作者 Edward LS Leen imam Waked Simon D Taylor-Robinson 《World Journal of Gastroenterology》 SCIE CAS CSCD 2009年第11期1301-1314,共14页
Hepatocellular carcinoma (HCC) is one of the commonest cancers worldwide, particularly in parts of the developing world, and is increasing in incidence. This article reviews the current modalities employed for the dia... Hepatocellular carcinoma (HCC) is one of the commonest cancers worldwide, particularly in parts of the developing world, and is increasing in incidence. This article reviews the current modalities employed for the diagnosis of HCC, including serum markers, radiological techniques and histological evaluation, and summarises international guidelines for the diagnostic approach to HCC. 展开更多
关键词 DIAGNOSIS Hepatocellular carcinoma IMAGING Serum markers
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Hepatocellular carcinoma surveillance:An evidence-based approach 被引量:39
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作者 Patrick S Harris Ross M Hansen +3 位作者 Meagan E Gray Omar i Massoud Brendan M McGuire Mohamed G Shoreibah 《World Journal of Gastroenterology》 SCIE CAS 2019年第13期1550-1559,共10页
Hepatocellular carcinoma(HCC) makes up 75%-85% of all primary liver cancers and is the fourth most common cause of cancer related death worldwide. Chronic liver disease is the most significant risk factor for HCC with... Hepatocellular carcinoma(HCC) makes up 75%-85% of all primary liver cancers and is the fourth most common cause of cancer related death worldwide. Chronic liver disease is the most significant risk factor for HCC with 80%-90% of new cases occurring in the background of cirrhosis. Studies have shown that early diagnosis of HCC through surveillance programs improve prognosis and availability of curative therapies. All patients with cirrhosis and high-risk hepatitis B patients are at risk for HCC and should undergo surveillance. The recommended surveillance modality is abdominal ultrasound(US) given that it is cost effective and noninvasive with good sensitivity. However, US is limited in obese patients and those with non-alcoholic fatty liver disease(NAFLD). With the current obesity epidemic and rise in the prevalence of NAFLD, abdominal computed tomography or magnetic resonance imaging may be indicated as the primary screening modality in these patients. The addition of alpha-fetoprotein to a surveillance regimen is thought to improve the sensitivity of HCC detection.Further investigation of serum biomarkers is needed. Semiannual screening is the suggested surveillance interval. Surveillance for HCC is underutilized and low adherence disproportionately affects certain demographics such as nonCaucasian race and low socioeconomic status. 展开更多
关键词 LIVER cancer HEPATOCELLULAR CARCINOMA SURVEILLANCE
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基于EEMD-Hilbert包络谱和DBN的变负载下滚动轴承状态识别方法 被引量:38
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作者 王玉静 那晓栋 +2 位作者 康守强 谢金宝 V i MiKULOViCH 《中国电机工程学报》 EI CSCD 北大核心 2017年第23期6943-6950,共8页
负载在滚动轴承的运行过程中通常是变化的,针对变负载下滚动轴承不同故障位置及不同性能退化程度多状态识别困难的问题,提出一种基于集合经验模态分解–希尔伯特(ensemble empirical mode decomposition-Hilbert,EEMD-Hilbert)包络谱和... 负载在滚动轴承的运行过程中通常是变化的,针对变负载下滚动轴承不同故障位置及不同性能退化程度多状态识别困难的问题,提出一种基于集合经验模态分解–希尔伯特(ensemble empirical mode decomposition-Hilbert,EEMD-Hilbert)包络谱和深度信念网络(deep belief network,DBN)的滚动轴承状态识别方法。该方法首先对滚动轴承各状态振动信号进行EEMD,然后选取敏感本征模态函数(intrinsic mode function,IMF),并对其进行Hilbert变换求取包络谱。最后将各状态振动信号的IMF包络谱按顺序构建新的高维数据,输入到经遗传算法优化各隐藏层节点结构的DBN中,实现变负载下滚动轴承的多状态识别。实验结果表明:在运用DBN进行滚动轴承10种状态识别过程中,训练数据采用某种负载,测试数据选用其他负载的情况下,EEMD-Hilbert包络谱比时域或频域幅值谱能更好地体现出滚动轴承不同负载下的多状态特征;且DBN相对浅层学习的支持向量机和BP神经网络算法,具有更高的识别率,各数据集识别率均达到92.5%以上。 展开更多
关键词 变负载 滚动轴承 集合经验模态分解 深度信念网络 状态识别
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对称四取代六元瓜环的合成及其2,2-联吡啶主客体化合物 被引量:22
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作者 赵云洁 薛赛凤 +7 位作者 祝黔江 陶朱 张建新 魏赞斌 龙腊生 胡茂林 肖洪平 Day Anthony i 《科学通报》 EI CAS CSCD 北大核心 2004年第11期1046-1051,共6页
利用二甲基取代甘脲的二醚与甘脲二聚体成功合成了新型取代六元瓜环——对称四甲基六元瓜环. 该瓜环的结构已被晶体结构鉴定、核磁共振谱以及质谱方法所证实, 分子中所含两个二甲基取代甘脲处于对位. 1H NMR表明该瓜环容易与吡啶衍生物... 利用二甲基取代甘脲的二醚与甘脲二聚体成功合成了新型取代六元瓜环——对称四甲基六元瓜环. 该瓜环的结构已被晶体结构鉴定、核磁共振谱以及质谱方法所证实, 分子中所含两个二甲基取代甘脲处于对位. 1H NMR表明该瓜环容易与吡啶衍生物形成主客体配合物. 展开更多
关键词 对称四甲基取代六元瓜环 晶体结构 核磁共振谱 质谱 主客体配合物 合成 2 2-联吡啶
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铝、镁轻合金中的稀土 被引量:36
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作者 Ferro R, Saccone A, Borzone G( Division of General and inorganic Chemistry and Metallurgy Department of Chemistry, University of Genova, Dodecaneso 31,i 16146 Genova, italy ) 《中国稀土学报》 CAS CSCD 北大核心 1997年第3期262-274,共13页
综述了稀土镁和稀土铝合金的晶体化学、热力学和相图数据,根据其应用前景特别注意了富镁、富铝稀土合金及添加稀土对合金性能的影响,报道了若干稀土镁、稀土铝及含两个不同稀土的镁、铝合金的研究结果。对富镁、富铝的二元和... 综述了稀土镁和稀土铝合金的晶体化学、热力学和相图数据,根据其应用前景特别注意了富镁、富铝稀土合金及添加稀土对合金性能的影响,报道了若干稀土镁、稀土铝及含两个不同稀土的镁、铝合金的研究结果。对富镁、富铝的二元和三元合金相的结晶化学及形成规律进行了总结和讨论,并对有确定结构的合金精细设计和可能的应用提出了建议。 展开更多
关键词 稀土合金 晶体化学 热力学 相图
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Evaluation of the suitability of a partially defatted black soldier fly (Hermetia illucens L.) larvae meal as ingredient for rainbow trout (Oncorhynchus mykiss Walbaum) diets 被引量:36
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作者 M. Renna A. Schiavone +11 位作者 F. Gai S. Dabbou C. Lussiana V. Malfatto M. Prearo M. T. Capucchio i. Biasato E. Biasibetti M. De Marco A. Brugiapaglia i. Zoccarato L. Gasco 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2017年第4期957-969,共13页
Background: Two trials were performed to evaluate a partially defatted Hermetia illucens(HI) larvae meal as potential feed ingredient in rainbow trout(Oncorhynchus mykiss Walbaum) diets. In the first trial, 360 trout(... Background: Two trials were performed to evaluate a partially defatted Hermetia illucens(HI) larvae meal as potential feed ingredient in rainbow trout(Oncorhynchus mykiss Walbaum) diets. In the first trial, 360 trout(178.9 ± 9.8 g of mean initial body weight) were randomly divided into three experimental groups(4 tanks/treatment, 30 fish/tank). The fish were fed for 78 days with isonitrogenous, isolipidic and isoenergetic diets containing increasing levels of HI, on as fed basis: 0%(HI0, control diet), 25%(HI25) and 50%(HI50) of fish meal substitution, corresponding to dietary inclusion levels of 0, 20% and 40%. In the second trial, 36 trout(4 tanks/treatment, 3 fish/tank) were used to evaluate the in vivo apparent digestibility coefficients(ADC) of the same diets used in the first trial.Results: Survival, growth performance, condition factor, somatic indexes, and dorsal fillet physical quality parameters were not affected by diet. The highest dietary inclusion of HI larvae meal increased dry matter and ether extract contents of trout dorsal fillet. The use of HI larvae meal induced a decrease of valuable polyunsaturated fatty acids(PUFA) even if differences were only reported at the highest level of HI inclusion. The insect meal worsened the lipids health indexes of the same muscle. Dietary inclusion of insect meal did not alter the villus height of the fish. No differences were found among treatments in relation to ADC of ether extract and gross energy, while ADC of dry matter and crude protein were higher in HI25 if compared to HI50.Conclusions: The obtained results showed that a partially defatted HI larvae meal can be used as feed ingredient in trout diets up to 40% of inclusion level without impacting survival, growth performance, condition factor, somatic indexes, dorsal fillet physical quality parameters, and intestinal morphology of the fish. However, further investigations on specific feeding strategies and diet formulations are needed to limit the observed negative effects of the insect meal on the FA 展开更多
关键词 Animal performance Apparent DIGESTIBILITY coefficient Carnivorous fish Fatty acids FISHMEAL substitution Insect MEAL
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