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简易智能状态检查量表和蒙特利尔认知评估量表在老年人认知功能障碍筛查中的比较 被引量:107
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作者 裴芳 孟涛 +6 位作者 张凯旋 米希婷 王娟 元佳 李亮 马存根 尉杰忠 《中国药物与临床》 CAS 2020年第11期1771-1774,共4页
目的比较简易智能状态检查量表(MMSE)和蒙特利尔认知评估量表(MoCA)在老人认知功能筛查中的作用。方法选择某煤矿社区156名老人,分别进行MMSE和MoCA测评,按年龄或受教育年限分组后,比较各组MMSE和MoCA总分,分析2种量表筛查认知障碍的敏... 目的比较简易智能状态检查量表(MMSE)和蒙特利尔认知评估量表(MoCA)在老人认知功能筛查中的作用。方法选择某煤矿社区156名老人,分别进行MMSE和MoCA测评,按年龄或受教育年限分组后,比较各组MMSE和MoCA总分,分析2种量表筛查认知障碍的敏感度和一致性。结果各组MoCA总分均显著低于MMSE总分(P<0.01),并呈正相关(P<0.01)。随年龄增加和受教育年限降低,MMSE和MoCA总分均显著降低(P<0.01)。各组中MoCA阳性筛查率显著高于MMSE(P<0.01),且一致性一般。结论MMSE和MoCA量表可以不同程度评定老年人认知功能减退,且MoCA筛查敏感度优于MMSE,这将为老年人认知障碍的评定提供较为客观数据。 展开更多
关键词 MOCA量表 MMSE量表 老年人 认知功能筛查 煤矿
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中国农作物秸秆资源分布及其产业体系与利用路径 被引量:103
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作者 丛宏斌 姚宗路 +7 位作者 赵立欣 孟海波 王久臣 霍丽丽 袁艳文 贾吉秀 谢腾 吴雨浓 《农业工程学报》 EI CAS CSCD 北大核心 2019年第22期132-140,共9页
中国具有丰富的农作物秸秆资源,推进农作物秸秆综合利用,不仅可减少田间焚烧环境污染、消除火灾隐患,还可增加农民收入、改善农村人居环境、促进农业可持续发展。基于中国大陆地区各省级行政区的统计数据,探讨了中国农作物秸秆资源构成... 中国具有丰富的农作物秸秆资源,推进农作物秸秆综合利用,不仅可减少田间焚烧环境污染、消除火灾隐患,还可增加农民收入、改善农村人居环境、促进农业可持续发展。基于中国大陆地区各省级行政区的统计数据,探讨了中国农作物秸秆资源构成与空间分布特征。玉米、水稻、小麦三大粮食作物秸秆占全国秸秆资源总量的84.8%;秸秆资源总体呈现出"东高西低、北高南低"的阶梯状分布特征。统揽中国秸秆产业发展全局,系统梳理并深入解析了中国秸秆产业政策体系、市场体系、技术体系和监管体系发展历程和现状。分别以单一利用、综合利用、战略布局和区域统筹为鲜明特征,将秸秆利用政策历程划分为政策起步期(1979-2007年)、政策发展期(2008-2012年)、政策转型期(2013-2016年)和政策深化期(2017年至今)。系统阐释了中国农作物秸秆农业利用、能源化利用和高值化利用的主要路径与模式。该研究可为指导中国秸秆资源开发利用提供重要的基础支撑和决策参考。 展开更多
关键词 秸秆 产业 作物 分布 产业体系 路径 模式
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北斗三号全球导航卫星系统服务性能评估:定位导航授时、星基增强、精密单点定位、短报文通信与国际搜救 被引量:81
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作者 蔡洪亮 孟轶男 +11 位作者 耿长江 高为广 张天桥 李罡 邵搏 辛洁 卢红洋 毛悦 袁海波 刘成 胡小工 楼益栋 《测绘学报》 EI CSCD 北大核心 2021年第4期427-435,共9页
本文给出了北斗三号全球导航卫星系统定位导航授时、星基增强、精密单点定位、区域短报文通信、全球短报文通信和国际搜救共6类服务的测试评估方法,并利用实测数据对各类服务的核心指标进行了评估。结果表明,定位导航授时服务方面,空间... 本文给出了北斗三号全球导航卫星系统定位导航授时、星基增强、精密单点定位、区域短报文通信、全球短报文通信和国际搜救共6类服务的测试评估方法,并利用实测数据对各类服务的核心指标进行了评估。结果表明,定位导航授时服务方面,空间信号测距误差0.23 m(RMS),空间信号可用性99.44%,空间信号连续性99.99%,PDOP可用性100%,B1C信号全球定位精度水平方向1.31 m、垂直方向2.13 m(95%),B1C信号全球定位可用性99.93%,B1C信号授时精度14.7 ns(95%);星基增强服务方面,定位精度水平方向1.03 m、垂直方向2.60 m(95%)、具有垂直引导能力的一类进近(APV-I)可用性100%;精密单点定位服务方面,定位精度水平方向0.17 m(95%)、垂直方向0.22 m(95%)、平均收敛时间9 min;区域短报文通信服务成功率99.6%,服务容量1530万次/h(上行)、935万次/h(下行);全球短报文通信服务成功率96.46%,服务容量40万次/h(上行)、21万次/h(下行);国际搜救服务方面,搜救信号接收成功率98.3%(发射功率37 dBm)。 展开更多
关键词 北斗三号全球导航卫星系统 定位导航授时 星基增强 精密单点定位 短报文通信 搜救 服务性能
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Rice MtN3/Saliva/SWEET Family Genes and Their Homologs in Cellular Organisms 被引量:60
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作者 meng yuan Shiping Wang 《Molecular Plant》 SCIE CAS CSCD 2013年第3期665-674,共10页
The MtN3/saliva/SWEET-type genes, existing either alone or in a family group, are found in diverse organisms, from monocellular protozoa to higher eukaryotes, indicating their importance in cellular organisms. These g... The MtN3/saliva/SWEET-type genes, existing either alone or in a family group, are found in diverse organisms, from monocellular protozoa to higher eukaryotes, indicating their importance in cellular organisms. These genes encode polytopic membrane proteins that feature an MtN3/saliva domain, also known as a PQ loop repeat, The rice MtN3/saliva/SWEET gene family consists of 21 members and is among the largest families in sequenced organisms. Accumulating data suggest that these genes are involved in multiple physiological processes, including reproductive development, senescence, environmental adaptation, and host-pathogen interaction, in different species. In rice, some members of the family, including Xa13/Os8N3/OsSWEET11, which is essential for reproductive development, are used by the pathogenic bacterium Xanthomonas oryzae pv. oryzae to invade its host. Emerging data have also revealed that at least some MtN3/saliva/SWEET-type proteins may regulate different physiological processes by facilitating ion transport via interaction with ion transporters or as sugar transporters. The accumulating knowledge about MtN3/saliva/SWEET- type genes will help to elucidate the molecular bases of their function in different organisms. 展开更多
关键词 MtN3/saliva PQ loop repeat membrane protein SWEET transporter.
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Massive individual orbital angular momentum channels for multiplexing enabled by Dammann gratings 被引量:59
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作者 Ting Lei meng Zhang +9 位作者 Yuru Li Ping Jia Gordon Ning Liu Xiaogeng Xu Zhaohui Li Changjun Min Jiao Lin Changyuan Yu Hanben Niu Xiaocong yuan 《Light(Science & Applications)》 SCIE EI CAS CSCD 2015年第1期463-469,共7页
Data transmission rates in optical communication systems are approaching the limits of conventional multiplexing methods.Orbital angular momentum(OAM)in optical vortex beams offers a new degree of freedom and the pote... Data transmission rates in optical communication systems are approaching the limits of conventional multiplexing methods.Orbital angular momentum(OAM)in optical vortex beams offers a new degree of freedom and the potential to increase the capacity of free-space optical communication systems,with OAM beams acting as information carriers for OAM division multiplexing(OAM-DM).We demonstrate independent collinear OAM channel generation,transmission and simultaneous detection using Dammann optical vortex gratings(DOVGs).We achieve 80/160 Tbit s^(-1) capacity with uniform power distributions along all channels,with 1600 individually modulated quadrature phase-shift keying(QPSK)/16-QAM data channels multiplexed by 10 OAM states,80 wavelengths and two polarizations.DOVG-enabled OAM multiplexing technology removes the bottleneck of massive OAM state parallel detection and offers an opportunity to raise optical communication systems capacity to Pbit s^(-1) level. 展开更多
关键词 holographic gratings MULTIPLEXING optical communications orbital angular momentum
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Transmission Dynamics of an Outbreak of the COVID-19 Delta Variant B.1.617.2——Guangdong Province,China,May-June 2021 被引量:59
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作者 meng Zhang Jianpeng Xiao +22 位作者 Aiping Deng Yingtao Zhang Yali Zhuang Ting Hu Jiansen Li Hongwei Tu Bosheng Li Yan Zhou Jun yuan Lei Luo Zimian Liang Youzhi Huang Guoqiang Ye Mingwei Cai Gongli Li Bo Yang Bin Xu Ximing Huang Yazun Cui Dongsheng Ren Yanping Zhang Min Kang Yan Li 《China CDC weekly》 2021年第27期584-586,共3页
On May 21,2021,a local case of coronavirus disease 2019(COVID-19)was confirmed in a 75-year-old woman(experienced onset of symptoms on May 18)in Liwan District,Guangzhou City,Guangdong Province,China.The number of inf... On May 21,2021,a local case of coronavirus disease 2019(COVID-19)was confirmed in a 75-year-old woman(experienced onset of symptoms on May 18)in Liwan District,Guangzhou City,Guangdong Province,China.The number of infections has increased in the following 10 days and led to 5 generations of transmission. 展开更多
关键词 GUANGDONG FIR BREAK
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企业慈善捐赠是伪善吗——基于股价崩盘风险视角的研究 被引量:55
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作者 曹海敏 孟元 《会计研究》 CSSCI 北大核心 2019年第4期89-96,共8页
什么原因促使企业进行慈善捐赠,本文结合股价崩盘风险独特视角,试图发现企业慈善捐赠背后的动机。研究发现:慈善捐赠与股价崩盘风险显著正相关,这可以用代理问题解释;进一步分析表明,慈善捐赠作为隐瞒负面信息的工具是加剧股价崩盘风险... 什么原因促使企业进行慈善捐赠,本文结合股价崩盘风险独特视角,试图发现企业慈善捐赠背后的动机。研究发现:慈善捐赠与股价崩盘风险显著正相关,这可以用代理问题解释;进一步分析表明,慈善捐赠作为隐瞒负面信息的工具是加剧股价崩盘风险的潜在途径,隐瞒的负面信息最终被资本市场发现,从而引发崩盘。因此,经理人出于自利动机不正当地使用慈善捐赠引发股价崩盘,而非慈善捐赠本身所致。本文同时发现,在信息透明度高的情景下,企业更倾向将慈善捐赠作为隐瞒负面信息的工具。 展开更多
关键词 慈善捐贈 股价崩盘风险 代理问题
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Preemptive analgesic effects of flurbiprofen axetil in patients undergoing radical resection of esophageal carcinoma via the left thoracic approach 被引量:55
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作者 Wang Yan Zhang Hong-bin +2 位作者 Xia Bin Wang Gong-ming Zhang meng-yuan 《Chinese Medical Journal》 SCIE CAS CSCD 2012年第4期579-582,共4页
Background Systemic non-steroidal anti-inflammatory drugs have been evaluated for their possible preemptive analgesic effects.The efficacy of flurbiprofen axetil for preemptive analgesia in patients undergoing radical... Background Systemic non-steroidal anti-inflammatory drugs have been evaluated for their possible preemptive analgesic effects.The efficacy of flurbiprofen axetil for preemptive analgesia in patients undergoing radical resection of esophageal carcinoma via the left thoracic approach needs further investigation.The aim of this study was to research the preemptive analgesic effects of flurbiprofen axetil in thoracic surgery,and the influence of preoperative administration on postoperative respiratory function.Methods This randomized,double-blind,controlled trial enrolled 60 patients undergoing radical resection of esophageal carcinoma via the left thoracic approach.Anesthesia management was standardized.Each patient was randomly assigned to receive either 100 mg flurbiprofen axetil intravenously 15 minutes before incision (PA group) or intravenous normal saline as a control (C group).Postoperative analgesia was with sufentanil delivered by patient-controlled analgesia pump.Postoperative sufentanil consumption,visual analog scale pain scores,plasma levels of interleukin-8,and oxygenation index were measured.Results Compared with the preoperative baseline,postoperative patients in the PA group had no obvious increase in pain scores (P 〉0.05),but patients in the C group had significantly increased pain scores (P〈0.05).Pain scores in the C group were significantly higher at 24 hours postoperatively than preoperatively.Intergroup comparisons showed lower visual analog scale scores at 2-24 hours postoperatively in the PA group than the C group (P 〈0.05).Sufentanil consumption and plasma interleukin-8 levels at 2 and 12 hours postoperatively were significantly lower in the PA group than the C group (P 〈0.05).The oxygenation index at 2 and 12 hours postoperatively was significantly higher in the PA group than the C group (P〈0.05).Conclusions Intravenous flurbiprofen axetil appears to have a preemptive analgesic effect in patients undergoing radical resection of esophageal carcinoma via 展开更多
关键词 flurbiprofen axetil preemptive analgesia radical resection esophageal carcinoma
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Expression of the SARS-CoV-2 cell receptor gene ACE2 in a wide variety of human tissues 被引量:53
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作者 meng-yuan Li Lin Li +1 位作者 Yue Zhang Xiao-Sheng Wang 《Infectious Diseases of Poverty》 SCIE 2020年第2期23-29,共7页
Background:Since its discovery in December 2019,severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)has infected more than 2180000 people worldwide and has caused more than 150000 deaths as of April 16,2020.SAR... Background:Since its discovery in December 2019,severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)has infected more than 2180000 people worldwide and has caused more than 150000 deaths as of April 16,2020.SARS-CoV-2,which is the virus causing coronavirus disease 2019(COVID-19),uses the angiotensin-converting enzyme 2(ACE2)as a cell receptor to invade human cells.Thus,ACE2 is the key to understanding the mechanism of SARS-CoV-2 infection.This study is to investigate the ACE2 expression in various human tissues in order to provide insights into the mechanism of SARS-CoV-2 infection.Methods:We compared ACE2 expression levels across 31 normal human tissues between males and females and between younger(ages≤49 years)and older(ages>49 years)persons using two-sided Student's t test.We also investigated the correlations between ACE2 expression and immune signatures in various tissues using Pearson's correlation test.Results:ACE2 expression levels were the highest in the small intestine,testis,kidneys,heart,thyroid,and adipose tissue,and were the lowest in the blood,spleen,bone marrow,brain,blood vessels,and muscle.ACE2 showed medium expression levels in the lungs,colon,liver,bladder,and adrenal gland.ACE2 was not differentially expressed between males and females or between younger and older persons in any tissue.In the skin,digestive system,brain,and blood vessels,ACE2 expression levels were positively associated with immune signatures in both males and females.In the thyroid and lungs,ACE2 expression levels were positively and negatively associated with immune signatures in males and females,respectively,and in the lungs they had a positive and a negative correlation in the older and younger groups,respectively.Conclusions:Our data indicate that SARS-CoV-2 may infect other tissues aside from the lungs and infect persons with different sexes,ages,and races equally.The different host immune responses to SARS-CoV-2 infection may partially explain why males and females,young and old persons infected with this vi 展开更多
关键词 SARS-CoV-2 COVID-19 SARS-CoV-2 cell receptor Angiotensin-converting enzyme 2 Gene expression SARS-CoV-2 pandemic Immune signatures
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多学科协作诊疗模式在老年髋部骨折治疗中的应用 被引量:46
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作者 王振威 艾笛 +9 位作者 张腾 俞猛 李洪川 彭立彬 于大昕 陈国强 袁晓明 于方 刘伟 姚琦 《中华创伤骨科杂志》 CAS CSCD 北大核心 2020年第3期200-205,共6页
目的探讨多学科协作诊疗模式(MDT)在老年髋部骨折治疗中的应用效果。方法回顾性分析2017年9月至2018年12月期间首都医科大学附属北京世纪坛医院关节外科收治的196例老年髋部骨折患者资料。根据是否应用MDT分为两组:MDT组102例,男43例,... 目的探讨多学科协作诊疗模式(MDT)在老年髋部骨折治疗中的应用效果。方法回顾性分析2017年9月至2018年12月期间首都医科大学附属北京世纪坛医院关节外科收治的196例老年髋部骨折患者资料。根据是否应用MDT分为两组:MDT组102例,男43例,女59例;年龄为(81.9±8.4)岁;股骨颈骨折63例,股骨转子间骨折39例。传统治疗组94例,男37例,女57例;年龄为(81.3±8.6)岁;股骨颈骨折55例,股骨转子间骨折39例。记录并比较两组患者住院期间并发症的发生率、住院期间病死率、入院至手术时间、住院时间及术后6个月髋关节Harris评分等。结果两组患者术前一般资料的比较差异均无统计学意义(P>0.05),具有可比性。传统治疗组84例(89.4%)、MDT组98例(96.1%)患者接受手术治疗,差异无统计学意义(χ2=3.327,P=0.068)。MDT组接受手术治疗患者术后谵妄[12.2%(12/98)]、肺部感染[11.2%(11/98)]、心源性疾病[13.3%(13/98)]、电解质紊乱[12.2%(12/98)]、下肢深静脉血栓形成的发生率[6.1%(6/98)]显著低于传统治疗组患者[31.0%(26/84)、22.6%(19/84)、25.0%(21/84)、28.6%(24/84)、16.7%(14/84)],入院至手术时间[(1.9±0.9)d]和住院时间[(10.2±0.9)d]显著短于传统治疗组患者[(3.1±1.6)、(14.1±6.2)d],术后6个月髋关节Harris评分[(81.3±6.2)分]显著高于传统治疗组患者[(75.4±7.8)分],差异均有统计学意义(P<0.05)。结论MDT在老年髋部骨折治疗中的应用效果显著,可降低患者住院期间并发症的发生率,缩短入院至手术时间及住院时间,有利于患者术后髋关节功能的恢复。 展开更多
关键词 髋骨折 骨折固定术 髓内 骨钉 关节成形术 置换 多学科协作
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创伤骨科患者围术期下肢静脉血栓形成诊断及防治专家共识(2022年) 被引量:44
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作者 周武 曹发奇 +44 位作者 曾睿寅 姜保国 唐佩福 吴新宝 余斌 侯志勇 黎健 苏佳灿 刘国栋 禹宝庆 袁志 倪江东 陈雁西 傅德皓 童培建 王栋梁 张殿英 张鹏 张云飞 牛丰 杨雷 杨强 施忠民 周强 王俊文 王勇 何承建 车彪 赵猛 夏平 熊蠡茗 曹烈虎 陈晓 李卉 孙云 胡良聪 胡衍 刘梦非 米博斌 熊元 薛航 林泽 张英泽 胡豫 刘国辉 《中华创伤杂志》 CAS CSCD 北大核心 2022年第1期23-31,共9页
下肢深静脉血栓形成(DVT)是创伤骨科患者的主要并发症之一,严重DVT甚至会影响动脉供血,出现相应肢体供血不足。若发生血栓脱落可并发肺栓塞,病死率较高。临床上下肢骨折患者DVT的治疗和康复策略均有其特殊性。创伤骨科患者并发DVT已经... 下肢深静脉血栓形成(DVT)是创伤骨科患者的主要并发症之一,严重DVT甚至会影响动脉供血,出现相应肢体供血不足。若发生血栓脱落可并发肺栓塞,病死率较高。临床上下肢骨折患者DVT的治疗和康复策略均有其特殊性。创伤骨科患者并发DVT已经引起广泛的关注与研究,预防和治疗DVT的最佳措施也在不断发展。近年来国内外陆续更新了一系列血栓防治指南,但临床上对于不同创伤骨折患者DVT的防治方式仍有不少疑惑。因此,笔者在总结国内外最新的循证医学证据和广大专家的临床经验基础上,针对创伤骨科患者DVT的临床诊疗和预防方案进行总结,就下肢DVT的诊断、评估、治疗及预防措施等方面制订本共识,为创伤骨科患者下肢DVT的处理提供一套适合我国国情且简便易行的方案,以期改善患者预后,提高其生活质量。 展开更多
关键词 创伤骨科患者 并发肺栓塞 循证医学证据 下肢静脉血栓形成 血栓脱落 下肢骨折患者 供血不足 动脉供血
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Inhibition of Alveolar Macrophage Pyroptosis Reduces Lipopolysaccharide-induced Acute Lung Injury in Mice 被引量:43
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作者 Dong-Dong Wu Pin-Hua Pan +9 位作者 Ben Liu Xiao-Li Su Le-meng Zhang Hong-Yi Tan ZU Cao Zuo-Ren Zhou Hai-Tao Li Hao-Si Li Li Huang yuan-yuan Li 《Chinese Medical Journal》 SCIE CAS CSCD 2015年第19期2638-2645,共8页
Background:Pyroptosis is the term for caspase-l-dependent cell death associated with pro-inflammatory cytokines.The role of alveolar macrophage (AM) pyroptosis in the pathogenesis of the acute lung injury and acute... Background:Pyroptosis is the term for caspase-l-dependent cell death associated with pro-inflammatory cytokines.The role of alveolar macrophage (AM) pyroptosis in the pathogenesis of the acute lung injury and acute respiratory distress syndrome (ALI/ARDS) remains unclear.Methods:C57BL/6 wild-type mice were assigned to sham,lipopolysaccharide (LPS) + vehicle,LPS + acetyl-tyrosyl-valyl-alanyl-aspartyl-chloromethylketone (Ac-YVAD-CMK) and LPS + Z-Asp-Glu-Val-Asp-fluoromethylketone groups.Mice were given intraperitoneal (IP) injections of LPS.Drugs were IP injected 1 h before LPS administration.Mice were sacrificed 16 h after LPS administration,and AMs were isolated.Western blot analysis for active caspase-1 and cleaved caspase-3,evaluation of lung injury and a cytokine release analysis were performed.AMs were treated with LPS and adenosine triphosphate (ATP);caspase-l-dependent cell death was evaluated using flow cytometry;the apoptosis-associated speck-like protein containing a caspase recruitment domain (ASC) pyroptosomes were examined by immunofluorescence.Results:The expression of activated caspase-1 in AMs was enhanced following LPS challenge compared with the sham group.In the ex vivo study,the caspase-1/propidium iodide-positive cells,caspase-1 specks and ASC pyroptosomes were up-regulated in AMs following LPS/ATP stimulation.The specific caspase-1 inhibitor Ac-YVAD-CMK inhibited the activation of caspase-1 and pyroptotic cell death.Ac-YVAD-CMK also reduced the lung injury,pulmonary edema and total protein in bronchoalveolar lavage fluid (BALF).In addition,Ac-YVAD-CMK significantly inhibited interleukin-β (IL-lβ) release both in serum and BALF and reduced the levels of IL-18,tumor necrosis factor-α (TNF-α),High Mobility Group Box 1 (HMGB1) in BALF during LPS-induced ALI/ARDS.Conclusions:This study reported AM pyroptosis during LPS-induced ALI/ARDS in mice and has demonstrated that Ac-YVAD-CMK can prevent AM-induced pyroptosis and lung injury.These 展开更多
关键词 Acute Lung Injury/Acute Respiratory Distress Syndrome Alveolar Macrophage CASPASE-1 PYROPTOSIS
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让理念照进现实:教育数字化转型框架设计及成熟度模型构建 被引量:35
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作者 祝智庭 孙梦 袁莉 《现代远程教育研究》 CSSCI 北大核心 2022年第6期3-11,共9页
教育数字化转型是建设数字中国、教育强国,以及实现教育现代化的必然要求,有助于提高教育系统韧性、推动教育高质量发展、创新教育生态。然而,当前我国教育数字化转型还处于初步发展阶段,学界主要集中于对其理念与价值的探讨。如何让教... 教育数字化转型是建设数字中国、教育强国,以及实现教育现代化的必然要求,有助于提高教育系统韧性、推动教育高质量发展、创新教育生态。然而,当前我国教育数字化转型还处于初步发展阶段,学界主要集中于对其理念与价值的探讨。如何让教育数字化转型的理念真正推进转型实践,成为迫切需要解决的难题。构建教育数字化转型框架与成熟度模型是连通理念与实践的关键桥梁。在充分借鉴和分析产业与教育领域数字化转型框架的共性和特性基础上,提出教育数字化转型框架应由价值层、应用层、主体层和支撑层四层架构构成,教育数字化转型成熟度模型应包括数字战略规划、智慧教学与评价、支持与服务、数字人才与文化、组织与生态、数字基础设施6个核心维度,涉及认知、起步、进阶、优化和成熟5个等级。该教育数字化转型框架及其成熟度模型具有相对统一的框架,有助于不同层次和不同类型的教育组织结合自身特点和需求,系统设计和规划差异性的数字化转型行动路线图。 展开更多
关键词 教育数字化 数字化转型 转型框架 成熟度模型 行动路线图
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2010年—2019年全国煤矿生产安全事故统计与现状分析 被引量:36
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作者 孟远 谢东海 +1 位作者 苏波 谷翱翔 《矿业工程研究》 2020年第4期27-33,共7页
依据中国煤矿安全生产网,对2010年—2019年煤矿生产安全事故资料进行统计,分析全国每年煤矿生产安全事故起数和死亡人数、事故类型、事故级别、百万吨死亡率以及各省煤矿生产安全事故起数和死亡人数等方面现状。分析表明:(1)2010年—201... 依据中国煤矿安全生产网,对2010年—2019年煤矿生产安全事故资料进行统计,分析全国每年煤矿生产安全事故起数和死亡人数、事故类型、事故级别、百万吨死亡率以及各省煤矿生产安全事故起数和死亡人数等方面现状。分析表明:(1)2010年—2019年,我国煤矿安全生产形势得到了大幅度的好转;(2)瓦斯、顶板、水灾事故仍为今后防治的重点;(3)重大、特大事故在近3年间基本消除,一般、较大事故还需加大治理力度;(4)2010年—2019年,山西省所发生的煤矿生产安全事故起数及死亡人数居全国第一。并建立GM(1,1)模型,运用Matlab软件对我国煤矿百万吨死亡率进行预测,得到2020年及2021年的百万吨死亡率预测值,具有一定的可靠性。 展开更多
关键词 煤矿事故 统计计算 事故规律 百万吨死亡率预测
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Wet Cupping Therapy Improves Local Blood Perfusion and Analgesic Effects in Patients with Nerve-Root Type Cervical Spondylosis 被引量:36
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作者 meng Xiang-wen WANG Ying +6 位作者 PIAO Sheng-ai LV Wen-tao ZHU Cheng-hui MU Ming-yuan LI Dan-dan LIU Hua-peng GUO Yi 《Chinese Journal of Integrative Medicine》 SCIE CAS CSCD 2018年第11期830-834,共5页
Objective: To observe wet cupping therapy(WCT) on local blood perfusion and analgesic effects in patients with nerve-root type cervical spondylosis(NT-CS). Methods: Fifty-seven NT-CS patients were randomly divid... Objective: To observe wet cupping therapy(WCT) on local blood perfusion and analgesic effects in patients with nerve-root type cervical spondylosis(NT-CS). Methods: Fifty-seven NT-CS patients were randomly divided into WCT group and Jiaji acupoint-acupuncture(JA) group according a random number table. WCT group(30 cases) was treated with WCT for 10 min, and JA group(27 cases) was treated with acupuncture for 10 min. The treatment efficacies were evaluated with a Visual Analogue Scale(VAS). Blood perfusion at Dazhui(GV 14) and Jianjing(GB 21) acupoints(affected side) was observed with a laser speckle flowmetry, and its variations before and after treatment in both groups were compared as well. Results: In both groups, the VAS scores significantly decreased after the intervention(P〈0.01), while the blood perfusion at the two acupoints significantly increased after intervention(P〈0.05); however, the increasement magnitude caused by WCT was obvious compared with JA(P〈0.05). Conclusion: WCT could improve analgesic effects in patients with NT-CS, which might be related to increasing local blood perfusion of acupunct points. 展开更多
关键词 wet cupping nerve-root type cervical spondylosis blood perfusion amount acupuncture Jiaji acupoint
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2020年中国垃圾分类背景下厨余垃圾处理热点回眸 被引量:35
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作者 蒋建国 耿树标 +10 位作者 罗维 江燕航 高语晨 陈哲红 杨国栋 兰天 孟园 鞠彤瑶 韩思宇 沈鹏飞 向虹霖 《科技导报》 CAS CSCD 北大核心 2021年第1期261-276,共16页
随着中国垃圾分类工作不断推进,厨余垃圾的分类收集及其处理处置凸显出诸多问题。梳理了中国垃圾分类政策的推行现状、厨余垃圾的产生和处理情况,重点回顾了厌氧消化、堆肥、生物干化、腐生生物养殖和物理预处理等几项关键的厨余垃圾处... 随着中国垃圾分类工作不断推进,厨余垃圾的分类收集及其处理处置凸显出诸多问题。梳理了中国垃圾分类政策的推行现状、厨余垃圾的产生和处理情况,重点回顾了厌氧消化、堆肥、生物干化、腐生生物养殖和物理预处理等几项关键的厨余垃圾处理技术在2020年取得的研究进展,整合了技术研究热点和相关工程案例,为中国厨余垃圾处理技术的进一步研发和应用提供指引。 展开更多
关键词 垃圾分类 厨余垃圾 资源化 减量化
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基于Michelson光纤干涉的GIS局部放电超声信号检测技术 被引量:35
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作者 周宏扬 马国明 +2 位作者 张猛 王渊 李成榕 《中国电机工程学报》 EI CSCD 北大核心 2019年第21期6452-6459,共8页
传统的局部放电超声检测技术主要是使用PZT传感器进行检测,但其性能已难以满足电力设备局部放电超声检测需求。近年来,研究人员对光纤超声传感器开展了大量研究,但缺乏针对传感器检测下限的研究,且测试较少在真实GIS平台上开展。为此,基... 传统的局部放电超声检测技术主要是使用PZT传感器进行检测,但其性能已难以满足电力设备局部放电超声检测需求。近年来,研究人员对光纤超声传感器开展了大量研究,但缺乏针对传感器检测下限的研究,且测试较少在真实GIS平台上开展。为此,基于Michelson干涉原理研制光纤超声传感系统,并研究芯轴尺寸对传感器性能的影响规律,搭建声发射传感器性能测试平台,探究光纤传感器对微弱超声信号的检测性能,优化传感单元设计方案。在此基础上,基于126 kV GIS开展干涉型光纤超声传感器局部放电检测性能测试。实验结果表明:所研制干涉式光纤超声传感系统可用于实际GIS设备局部放电超声信号检测,所研制的光纤超声传感器平均灵敏度为82.5dB(0dB=1V/(m×s-1)),比PZT传感器(R15a)高18.7dB。对于GIS壳体尖端放电,光纤超声传感器的局部放电检测电压比PZT低44%,可测放电量低37.2%。在相同超声信号激励下,光纤传感器最大响应幅值比PZT高552%。 展开更多
关键词 局部放电 超声 光纤传感器 Michelson干涉 气体绝缘开关设备
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Different treatment strategies and molecular features between right-sided and left-sided colon cancers 被引量:35
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作者 Hong Shen Jiao Yang +6 位作者 Qing Huang meng-Jie Jiang Yi-Nuo Tan Jian-Fei Fu Li-Zhen Zhu Xue-Feng Fang Ying yuan 《World Journal of Gastroenterology》 SCIE CAS 2015年第21期6470-6478,共9页
The colon is derived from the embryological midgut and hindgut separately,with the right colon and left colon having different features with regards to both anatomical and physiological characteristics.Cancers located... The colon is derived from the embryological midgut and hindgut separately,with the right colon and left colon having different features with regards to both anatomical and physiological characteristics.Cancers located in the right and left colon are referred to as right colon cancer(RCC) and left colon cancer(LCC),respectively,based on their apparent anatomical positions.Increasing evidence supports the notion that not only are there differences in treatment strategies when dealing with RCC and LCC,but molecular features also vary between them,not to mention the distinguishing clinical manifestations.Disease-free survival after radical surgery of both RCC and LCC are similar.In the treatment of RCC,the benefit gained from adjuvant FOLFIRI chemotherapy is superior,or at least similar,to LCC,but inferior to LCC if FOLFOX regimen is applied.On the other hand,metastatic LCC exhibits longer survival than that of RCC in a palliative chemotherapy setting.For KRAS wild-type cancers,LCC benefits more from cetuximab treatment than RCC.Moreover,advanced LCC shows a higher sensitivity to bevacizumab treatment in comparison with advanced RCC.Significant varieties exist at the molecular level between RCC and LCC,which may serve as the cause of all apparent differences.With respect to carcinogenesis mechanisms,RCC is associated with known gene types,such as MMR,KRAS,BRAF,and mi RNA-31,while LCC is associated with CIN,p53,NRAS,mi RNA-146 a,mi RNA-147 b,and mi RNA-1288.Regarding protein expression,RCC is related to GNAS,NQO1,telomerase activity,P-PDH,and annexin A10,while LCC is related to Topo I,TS,and EGFR.In addition,separated pathways dominate progressionto relapse in RCC and LCC.Therefore,RCC and LCC should be regarded as two heterogeneous entities,with this heterogeneity being used to stratify patients in order for them to have the optimal,current,and novel therapeutic strategies in clinical practice.Additional research is needed to uncover further differences between RCC and LCC. 展开更多
关键词 COLON cancer RIGHT LEFT SURVIVAL MOLECULAR
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The first data release(DR1) of the LAMOST regular survey 被引量:29
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作者 A-Li Luo Yong-Heng Zhao +134 位作者 Gang Zhao Li-Cai Deng Xiao-Wei Liu Yi-Peng Jing Gang Wang Hao-Tong Zhang Jian-Rong Shi Xiang-Qun Cui Yao-Quan Chu Guo-Ping Li Zhong-Rui Bai Yue Wu Yan Cai Shu-Yun Cao Zi-Huang Cao Jeffrey L.Carlin Hai-yuan Chen Jian-Jun Chen Kun-Xin Chen Li Chen Xue-Lei Chen Xiao-Yan Chen Ying Chen Norbert Christlieb Jia-Ru Chu Chen-Zhou Cui Yi-Qiao Dong Bing Du Dong-Wei Fan Lei Feng Jian-Ning Fu Peng Gao Xue-Fei Gong Bo-Zhong Gu Yan-Xin Guo Zhan-Wen Han Bo-Liang He Jin-Liang Hou Yong-Hui Hou Wen Hou Hong-Zhuan Hu Ning-Sheng Hu Zhong-Wen Hu Zhi-Ying Huo Lei Jia Fang-Hua Jiang Xiang Jiang Zhi-Bo Jiang Ge Jin Xiao Kong Xu Kong Ya-Juan Lei Ai-Hua Li Chang-Hua Li Guang-Wei Li Hai-Ning Li Jian Li Qi Li Shuang Li Sha-Sha Li Xin-Nan Li Yan Li Yin-Bi Li Ye-Ping Li yuan Liang Chien-Cheng Lin Chao Liu Gen-Rong Liu Guan-Qun Liu Zhi-Gang Liu Wen-Zhi Lu Yu Luo Yin-Dun Mao Heidi Newberg Ji-Jun Ni Zhao-Xiang Qi Yong-Jun Qi Shi-Yin Shen Huo-Ming Shi Jing Song Yi-Han Song Ding-Qiang Su Hong-Jun Su Zheng-Hong Tang Qing-Sheng Tao yuan Tian Dan Wang Da-Qi Wang Feng-Fei Wang Guo-Min Wang Hai Wang Hong-Chi Wang Jian Wang Jia-Ning Wang Jian-Ling Wang Jian-Ping Wang Jun-Xian Wang Lei Wang meng-Xin Wang Shou-Guan Wang Shu-Qing Wang Xia Wang Ya-Nan Wang You Wang Yue-Fei Wang You-Fen Wang Peng Wei Ming-Zhi Wei Hong Wu Ke-Fei Wu Xue-Bing Wu Yu-Zhong Wu Xiao-Zheng Xing Ling-Zhe Xu Xin-Qi Xu Yan Xu Tai-Sheng Yan De-Hua Yang Hai-Feng Yang Hui-Qin Yang Ming Yang Zheng-Qiu Yao Yong Yu Hui yuan Hai-Bo yuan Hai-Long yuan Wei-Min yuan Chao Zhai En-Peng Zhang Hua-Wei Zhang Jian-Nan Zhang Li-Pin Zhang Wei Zhang Yong Zhang Yan-Xia Zhang 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2015年第8期1095-1124,共30页
The Large sky Area Multi-Object Fiber Spectroscopic Telescope(LAMOST) general survey is a spectroscopic survey that will eventually cover approximately half of the celestial sphere and collect 10 million spectra of ... The Large sky Area Multi-Object Fiber Spectroscopic Telescope(LAMOST) general survey is a spectroscopic survey that will eventually cover approximately half of the celestial sphere and collect 10 million spectra of stars, galaxies and QSOs. Objects in both the pilot survey and the first year regular survey are included in the LAMOST DR1. The pilot survey started in October 2011 and ended in June 2012, and the data have been released to the public as the LAMOST Pilot Data Release in August 2012. The regular survey started in September 2012, and completed its first year of operation in June 2013. The LAMOST DR1 includes a total of 1202 plates containing 2 955 336 spectra, of which 1 790 879 spectra have observed signalto-noise ratio(SNR) ≥ 10. All data with SNR ≥ 2 are formally released as LAMOST DR1 under the LAMOST data policy. This data release contains a total of 2 204 696 spectra, of which 1 944 329 are stellar spectra, 12 082 are galaxy spectra and 5017 are quasars. The DR1 not only includes spectra, but also three stellar catalogs with measured parameters: late A,FGK-type stars with high quality spectra(1 061 918 entries), A-type stars(100 073 entries), and M-type stars(121 522 entries). This paper introduces the survey design, the observational and instrumental limitations, data reduction and analysis, and some caveats. A description of the FITS structure of spectral files and parameter catalogs is also provided. 展开更多
关键词 techniques: spectroscopic survey—data release—catalog
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致密油储集层高效缝网改造与提高采收率一体化技术 被引量:32
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作者 周福建 苏航 +4 位作者 梁星原 孟磊峰 袁立山 李秀辉 梁天博 《石油勘探与开发》 SCIE EI CAS CSCD 北大核心 2019年第5期1007-1014,共8页
基于对提高致密油储集层压裂改造效果面临挑战的分析,提出高效缝网改造与提高采收率一体化技术。通过调研发现,形成密集有效的裂缝网络以及提高压裂液的渗吸效果是目前所面临的两大挑战。针对这两大挑战,通过室内实验模拟与现场应用效... 基于对提高致密油储集层压裂改造效果面临挑战的分析,提出高效缝网改造与提高采收率一体化技术。通过调研发现,形成密集有效的裂缝网络以及提高压裂液的渗吸效果是目前所面临的两大挑战。针对这两大挑战,通过室内实验模拟与现场应用效果评估,提出一套适用于中国致密油开发的高效缝网改造与提高采收率一体化技术:①利用暂堵剂实现段内多簇改造,形成密集裂缝网络,可以最大化储集层的泄油面积;②利用微支撑剂,在前置液造缝阶段对大量诱导性裂缝进行有效支撑,可以形成有效密集缝网;③利用一种新型的纳米乳液体系(LNF)作为压裂液添加剂,提高油水置换效率,可以高效利用“万方压裂液”实现储集层的增能压裂开发。 展开更多
关键词 致密油 水力压裂 渗吸采油 暂堵剂 微支撑剂 纳米流体 表面活性剂 提高采收率
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