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术后活动性疼痛护理评估对疼痛管理质量的影响 被引量:162
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作者 成燕 童莺歌 +3 位作者 刘敏君 田素明 alex H.Konstantatos Dana Boyd 《中华护理杂志》 CSCD 北大核心 2015年第8期924-928,共5页
目的探讨术后活动性疼痛护理评估对疼痛管理质量的影响。方法将140例胸腹部术后1d的患者分为实验组和对照组。实验组在接受病区护士的术后疼痛护理措施的基础上,由疼痛专科护士采用功能活动评分法(Functional Activity Score,FAS)和数... 目的探讨术后活动性疼痛护理评估对疼痛管理质量的影响。方法将140例胸腹部术后1d的患者分为实验组和对照组。实验组在接受病区护士的术后疼痛护理措施的基础上,由疼痛专科护士采用功能活动评分法(Functional Activity Score,FAS)和数字评定量表(Numerical Rating Scale,NRS)评估活动性疼痛,并根据评估结果实施干预措施。对照组仅接受病区护士实施的术后疼痛护理措施。结果实验组和对照组术后24h内镇痛治疗方案调整及功能活动前按压镇痛泵比例的差异具有统计学意义(χ2=7.937,χ2=37.303,均P<0.05)。实验组在术后24h时间点的FAS评级结果、患者自评静息性和活动性疼痛强度,以及术后24h内疼痛最剧烈程度、中重度疼痛发生频度及有效咳嗽受疼痛影响程度均低于对照组(P<0.05),首次下床活动时间也早于对照组(P<0.05)。结论开展活动性疼痛护理评估实践有助于提高术后疼痛管理质量。 展开更多
关键词 疼痛 手术后 护理评估 疼痛管理
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垂直流人工湿地水力学特点对污水净化效果的影响 被引量:84
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作者 吴振斌 任明迅 +2 位作者 付贵萍 贺锋 alex Pressl 《环境科学》 EI CAS CSCD 北大核心 2001年第5期45-49,共5页
通过在污水中加入示踪剂 ,研究了人工湿地的水力学特点及其对污水净化效果的影响规律 .结果表明 ,影响水力学各特点的主要原因是湿地植物根系所造成的物理学和生物学上的效应 .水力学各特点与污水净化效果之间存在着密切关系 :出水快、... 通过在污水中加入示踪剂 ,研究了人工湿地的水力学特点及其对污水净化效果的影响规律 .结果表明 ,影响水力学各特点的主要原因是湿地植物根系所造成的物理学和生物学上的效应 .水力学各特点与污水净化效果之间存在着密切关系 :出水快、出水量大的系统具有较好的净化效果 ;除无植物系统外 ,停留时间较长的系统有较好的净化效果 ;容水体积大的系统净化效果也较好 ;水力负荷则主要通过影响其他各水力学特点而影响净化效果 .结果表明 。 展开更多
关键词 垂直流人工湿地 示踪剂 水力学特点 污水净化效果 废水处理
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The Open Quantum Materials Database (OQMD): assessing the accuracy of DFT formation energies 被引量:72
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作者 Scott Kirklin James E Saal +5 位作者 Bryce Meredig alex Thompson Jeff W Doak Muratahan Aykol Stephan Rühl Chris Wolverton 《npj Computational Materials》 SCIE EI 2015年第1期15-29,共15页
The Open Quantum Materials Database(OQMD)is a high-throughput database currently consisting of nearly 300,000 density functional theory(DFT)total energy calculations of compounds from the Inorganic Crystal Structure D... The Open Quantum Materials Database(OQMD)is a high-throughput database currently consisting of nearly 300,000 density functional theory(DFT)total energy calculations of compounds from the Inorganic Crystal Structure Database(ICSD)and decorations of commonly occurring crystal structures.To maximise the impact of these data,the entire database is being made available,without restrictions,at www.oqmd.org/download.In this paper,we outline the structure and contents of the database,and then use it to evaluate the accuracy of the calculations therein by comparing DFT predictions with experimental measurements for the stability of all elemental ground-state structures and 1,670 experimental formation energies of compounds.This represents the largest comparison between DFT and experimental formation energies to date.The apparent mean absolute error between experimental measurements and our calculations is 0.096 eV/atom.In order to estimate how much error to attribute to the DFT calculations,we also examine deviation between different experimental measurements themselves where multiple sources are available,and find a surprisingly large mean absolute error of 0.082 eV/atom.Hence,we suggest that a significant fraction of the error between DFT and experimental formation energies may be attributed to experimental uncertainties.Finally,we evaluate the stability of compounds in the OQMD(including compounds obtained from the ICSD as well as hypothetical structures),which allows us to predict the existence of~3,200 new compounds that have not been experimentally characterised and uncover trends in material discovery,based on historical data available within the ICSD. 展开更多
关键词 QUANTUM DFT OPEN
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垂直流人工湿地系统中水流规律的研究 被引量:47
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作者 付贵萍 吴振斌 +3 位作者 任明迅 贺锋 alex Pressl Reinhard Perfler 《环境科学学报》 CAS CSCD 北大核心 2001年第6期720-725,共6页
对一种新型的垂直流人工湿地系统的水流特性进行了研究 .考察了系统的运行状况及介质中滞留区的分布范围 ,并且运用化学工程中反应器理论 ,采用示踪剂试验的方法得到了垂直流人工湿地系统的停留时间分布与污水的实际停留时间 .根据水流... 对一种新型的垂直流人工湿地系统的水流特性进行了研究 .考察了系统的运行状况及介质中滞留区的分布范围 ,并且运用化学工程中反应器理论 ,采用示踪剂试验的方法得到了垂直流人工湿地系统的停留时间分布与污水的实际停留时间 .根据水流停留时间分布函数对系统实际液流流态进行了数学模拟 ,提出二级串联的理想完全混合反应器 (CSTR) 展开更多
关键词 垂直流人工湿地 水流分布 示踪剂 完全混合反应器 CSTR 水流规律 废水处理 污水净化
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北京空气质量多模式集成预报系统的建立及初步应用 被引量:63
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作者 王自发 吴其重 +4 位作者 alex GBAGUIDI 晏平仲 张伟 王威 唐晓 《南京信息工程大学学报(自然科学版)》 CAS 2009年第1期19-26,共8页
介绍了北京空气质量多模式集成预报系统(EMS-Beijing).系统中区域空气质量模式包括中国科学院大气物理所自主开发的嵌套网格空气质量模式系统(NAQPMS)模式、美国环保署(EPA)开发的Models-3/CMAQ模式及美国Environ公司开发的CAM... 介绍了北京空气质量多模式集成预报系统(EMS-Beijing).系统中区域空气质量模式包括中国科学院大气物理所自主开发的嵌套网格空气质量模式系统(NAQPMS)模式、美国环保署(EPA)开发的Models-3/CMAQ模式及美国Environ公司开发的CAMx模式等,均使用SMOKE排放模型统一处理大气污染排放清单.此系统各模式采用统一的模拟区域和网格分辨率,采用中尺度气象模式MM5提供统一的气象场,并采用算术平均、权重集成等方法集成各空气质量模式结果,并投入北京空气质量业务预报,有效支持了北京奥运会空气质量数值预报.业务预报结果表明:1)采用SMOKE处理的奥运排放清单较接近实际,2008年8月各空气质量模式可吸入颗粒物(PM10)日均值预报结果相对偏差为-3%~17%,与观测数据相关系数在0.7以上;2)在排放清单较接近实际的情况下,PM10日均值多模式算术平均优于单个空气质量模式;3)分析2008年4—11月业务预报表明,采用权重集成方法预报的PM10日均值优于算术平均方法,达61%.总体上,权重集成方法优于算术平均结果. 展开更多
关键词 空气质量 多模式 集成 PM10
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复合垂直流湿地反应动力学及水流流态的研究 被引量:27
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作者 付贵萍 吴振斌 +4 位作者 任明迅 贺锋 成水平 alex Pressl Reinhard Perfler 《中国环境科学》 EI CAS CSSCI CSCD 北大核心 2001年第6期535-539,共5页
提出一种新型的复合垂直流湿地系统(IVCW),并对其反应动力学和系统的实际流态进行了研究.经过中试的运行试验,得到了系统对COD去除的反应速率方程,由示踪剂试验确定了系统中水流的停留时间分布(RTD),提出RTD的不同是湿地处理效率差异的... 提出一种新型的复合垂直流湿地系统(IVCW),并对其反应动力学和系统的实际流态进行了研究.经过中试的运行试验,得到了系统对COD去除的反应速率方程,由示踪剂试验确定了系统中水流的停留时间分布(RTD),提出RTD的不同是湿地处理效率差异的主要原因,进而运用串联反应器模型和离散流模型两种非理想流态模型,模拟IVCW的实际水流流态,经过比较发现离散流模型模拟的效果较好. 展开更多
关键词 复合垂直流湿地 反应动力学 停留时间分布 RTD 串联反应器模型 离散流模型 水流流态 废水处理
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多模式模拟评估奥运赛事期间可吸入颗粒物减排效果 被引量:38
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作者 吴其重 王自发 +2 位作者 徐文帅 黄江平 alex Gbaguidi 《环境科学学报》 CAS CSCD 北大核心 2010年第9期1739-1748,共10页
以空气质量多模式系统为工具,分析奥运赛事期间可吸入颗粒物(PM10)浓度大幅减小特征,从气象场和排放源两方面研究PM10浓度大幅减小的主要原因.多模式系统由嵌套网格空气质量模式(NAQPMS)、通用空气质量多尺度模式(CMAQ)和复杂大气空气... 以空气质量多模式系统为工具,分析奥运赛事期间可吸入颗粒物(PM10)浓度大幅减小特征,从气象场和排放源两方面研究PM10浓度大幅减小的主要原因.多模式系统由嵌套网格空气质量模式(NAQPMS)、通用空气质量多尺度模式(CMAQ)和复杂大气空气质量三维模式(CAMx)3个空气质量复合模型组成,并以中尺度气象模式(MM5)和稀疏矩阵排放处理模型(SMOKE)提供统一气象场及排放源.研究对比2006年8月、2008年8月两组气象条件下北京PM10浓度水平及模拟效果,结果表明奥运赛事期间PM10浓度大幅减小的主要原因不是气象因素,而是由于额外措施引起的PM10排放减少.同时采用多模式系统数值模拟反向评估,获得北京奥运赛事期间奥运控制及额外减排措施引起的PM10减排量,结果表明,奥运赛事期间所有额外控制措施对颗粒物浓度效果相当于在2008年8月气象条件下,削减大约200t.d-1的无组织PM10排放,相当于北京正常时期PM10排放的50%. 展开更多
关键词 奥运赛事期间 PM10 排放量评估 空气质量多模式
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Achieving the best bowel preparation for colonoscopy 被引量:38
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作者 Adolfo Parra-Blanco alex Ruiz +5 位作者 Manuel Alvarez-Lobos Ana Amorós Juan Cristóbal Gana Patricio Ibáez Akiko Ono Takahiro Fujii 《World Journal of Gastroenterology》 SCIE CAS 2014年第47期17709-17726,共18页
Bowel preparation is a core issue in colonoscopy,as it is closely related to the quality of the procedure.Patients often find that bowel preparation is the most unpleasant part of the examination.It is widely accepted... Bowel preparation is a core issue in colonoscopy,as it is closely related to the quality of the procedure.Patients often find that bowel preparation is the most unpleasant part of the examination.It is widely accepted that the quality of cleansing must be excellent to facilitate detecting neoplastic lesions.In spite of its importance and potential implications,until recently,bowel preparation has not been the subject of much study.The most commonly used agents are high-volume polyethylene glycol(PEG)electrolyte solution and sodium phosphate.There has been some confusion,even in published meta-analyses,regarding which of the two agents provides better cleansing.It is clear now that both PEG and sodium phosphate are effectivewhen administered with proper timing.Consequently,the timing of administration is recognized as one of the central factors to the quality of cleansing.The bowel preparation agent should be administered,at least in part,a few hours in advance of the colonoscopy.Several low volume agents are available,and either new or modified schedules with PEG that usually improve tolerance.Certain adjuvants can also be used to reduce the volume of PEG,or to improve the efficacy of other agents.Other factors apart from the choice of agent can improve the quality of bowel cleansing.For instance,the effect of diet before colonoscopy has not been completely clarified,but an exclusively liquid diet is probably not required,and a low-fiber diet may be preferable because it improves patient satisfaction and the quality of the procedure.Some patients,such as diabetics and persons with heart or kidney disease,require modified procedures and certain precautions.Bowel preparation for pediatric patients is also reviewed here.In such cases,PEG remains the most commonly used agent.As detecting neoplasia is not the main objective with these patients,less intensive preparation may suffice.Special considerations must be made for patients with inflammatory bowel disease,including safety and diagnostic issues,so that the most a 展开更多
关键词 COLONOSCOPY Optimal preparation Polyethylene glycol Sodium phosphate Special patients TIMING
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典型夏季珠江三角洲地区植被的异戊二烯排放 被引量:36
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作者 司徒淑娉 王雪梅 +2 位作者 alex Guenther 柴子为 邓儒儒 《环境科学学报》 CAS CSCD 北大核心 2009年第4期822-829,共8页
利用中巴卫星影像采用监督分类的方法对影像进行解译,并反演珠江三角洲4种主要的植被类型(PFT).利用自然排放气体和气溶胶模式——MEGAN(Model of Emissions of Gases and Aerosols from Nature),对典型夏季日珠江三角洲地区植被异戊二... 利用中巴卫星影像采用监督分类的方法对影像进行解译,并反演珠江三角洲4种主要的植被类型(PFT).利用自然排放气体和气溶胶模式——MEGAN(Model of Emissions of Gases and Aerosols from Nature),对典型夏季日珠江三角洲地区植被异戊二烯的排放进行了初步研究.结果显示:估算日珠江三角洲植被异戊二烯总的排放量为1.73×106kg(以C计,下同).异戊二烯的排放有明显的日变化特征,最大排放量出现在14:00,为2.39×105kg.广州、江门和惠州的异戊二烯平均排放速率最大,分别为4580g·km-·2h-1、4250g·km-·2h-1和4130g·km-·2h-1;同时江门和惠州也为异戊二烯日排放量的高值区,其日排放总量分别为4.60×105kg和4.29×105kg,排放贡献率分别为26.6%和24.8%. 展开更多
关键词 异戊二烯 植被 MEGAN 珠三角
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Sarcopenia in heart failure: mechanisms and therapeutic strategies 被引量:28
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作者 Agnese Collamati Emanuele Marzetti +4 位作者 Riccardo Calvani Matteo Tosato Emanuela D'Angelo alex N Sisto Francesco Landi 《Journal of Geriatric Cardiology》 SCIE CAS CSCD 2016年第7期615-624,共10页
Chronic heart failure (CHF) is a highly prevalent condition among the elderly and is associated with considerable morbidity, institution-alization and mortality. In its advanced stages, CHF is often accompanied by t... Chronic heart failure (CHF) is a highly prevalent condition among the elderly and is associated with considerable morbidity, institution-alization and mortality. In its advanced stages, CHF is often accompanied by the loss of muscle mass and strength. Sarcopenia is a geriatric syndrome that has been actively studied in recent years due to its association with a wide range of adverse health outcomes. The goal of this review is to discuss the relationship between CHF and sarcopenia, with a focus on shared pathophysiological pathways and treatments. Mal- nutrition, systemic inflammation, endocrine imbalances, and oxidative stress appear to connect sarcopenia and CHF. At the muscular level, alterations of the ubiquitin proteasome system, myostatin signaling, and apoptosis have been described in both sarcopenia and CHF and could play a role in the loss of muscle mass and function. Possible therapeutic strategies to impede the progression of muscle wasting in CHF patients include protein and vitamin D supplementation, structured physical exercise, and the administration of angiotensin-converting enzyme inhibitors and β-blockers. Hormonal supplementation with growth hormone, testosterone, and ghrelin is also discussed as a potential treatment. 展开更多
关键词 GHRELIN Muscle loss Protein supplementation Vitamin D
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Modern management of rectal cancer: A 2006 update 被引量:26
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作者 Glen C Balch alex De Meo Jose G Guillem 《World Journal of Gastroenterology》 SCIE CAS CSCD 2006年第20期3186-3195,共10页
The goal of this review is to outline some of the important surgical issues surrounding the management of patients with early (T1/T2 and NO), as well as locally advanced (T3/T4 and/or N1) rectal cancer. Surgery for re... The goal of this review is to outline some of the important surgical issues surrounding the management of patients with early (T1/T2 and NO), as well as locally advanced (T3/T4 and/or N1) rectal cancer. Surgery for rectal cancer continues to develop towards the ultimate goals of improved local control and overall survival, maintaining quality of life, and preserving sphincter, genitourinary, and sexual function. Information concerning the depth of tumor penetration through the rectal wall, lymph node involvement, and presence of distant metastatic disease is of crucial importance when planning a curative rectal cancer resection. Preoperative staging is used to determine the indication for neoadjuvant therapy as well as the indication for local excision versus radical cancer resection. Local excision is likely to be curative in most patients with a primary tumor which is limited to the submucosa (T1N0M0), without high-risk features and in the absence of metastatic disease. In appropriate patients, minimally invasive procedures, such as local excision, TEM, and laparoscopic resection allow for improved patient comfort, shorter hospital stays, and earlier return to preoperative activity level. Once the tumor invades the muscularis propria (T2), radical rectal resection in acceptable operative candidates is recommended. In patients with transmural and/or node positive disease (T3/T4 and/or N1) with no distant metastases, preoperative chemoradiation followed by radical resection according to the principles of TME has become widely accepted. During the planning and conduct of a radical operation for a locally advanced rectal cancer, a number of surgical management issues are considered, including: (1) total mesorectal excision (TME); (2) autonomic nerve preservation (ANP); (3) circumferential resection margin (CRM); (4) distal resection margin; (5) sphincter preservation and options for restoration of bowel continuity; (6) laparoscopic approaches; and (7) postoperative quality of life. 展开更多
关键词 Rectal cancer SURGERY Local surgery Total mesorectal excision REVIEW
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Photocatalysts for degradation of dyes in industrial effluents:Opportunities and challenges 被引量:27
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作者 Hassan Anwer Asad Mahmood +3 位作者 Jechan Lee Ki-Hyun Kim Jae-Woo Park alex C.K.Yip 《Nano Research》 SCIE EI CAS CSCD 2019年第5期955-972,共18页
Discharging dye contaminants into water is a major concern around the world.Among a variety of methods to treat dye-contaminated water,photocatalytic degradation has gained attention as a tool for treating the colored... Discharging dye contaminants into water is a major concern around the world.Among a variety of methods to treat dye-contaminated water,photocatalytic degradation has gained attention as a tool for treating the colored water.Herein,we review the recent advancements in photocatalysis for dye degradation in industrial effluents by categorizing photocatalyst materials into three generations.First generation photocatalysts are composed of single-component materials (e.g.,TiO2,ZnO,and CdS),while second generation photocatalysts are composed of multiple components in a suspension (e.g.,WO3/NiWO4,BiOl/ZnTiOa,and C3N4/Ag3VO4).Photocatalysts immobilized on solid substrates are regarded as third generation materials (e.g.,FTO/WO3-ZnO,Steel/TiO2-WO3,and Glass/P-TiO2).Photocatalytic degradation mechanisms,factors affecting the dye degradation,and the lesser-debated uncertainties related to the photocatalysis are also discussed to offer better insights into environmental applications.Furthermore,quantum yields of different photocatalysts are calculated,and a performance evaluation method is proposed to compare photocatalyst systems for dye degradation.Finally,we discuss the present limitations of photocatalytic dye degradation for field applications and the future of the technology. 展开更多
关键词 PHOTOCATALYST DYE WASTEWATER DEGRADATION mechanism performance evaluation
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The wonders of BMP9:From mesenchymal stem cell differentiation,angiogenesis,neurogenesis,tumorigenesis,and metabolism to regenerative medicine 被引量:19
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作者 Sami Mostafa Mikhail Pakvasa +26 位作者 Elam Coalson Allen Zhu alex Alverdy Hector Castillo Jiaming Fan alex Li Yixiao Feng Di Wu Elliott Bishop Scott Du Mia Spezia Alissa Li Ofir Hagag Alison Deng Winny Liu Mingyang Li Sherwin S·Ho Aravind Athiviraham Michael J·Lee Jennifer Moriatis Wolf Guillermo A·Ameer Hue H·Luu Rex C·Haydon Jason Strelzow Kelly Hynes Tong-Chuan He Russell R·Reid 《Genes & Diseases》 SCIE 2019年第3期201-223,共23页
Although bone morphogenetic proteins(BMPs)initially showed effective induction of ectopic bone growth in muscle,it has since been determined that these proteins,as members of the TGF-b superfamily,play a diverse and c... Although bone morphogenetic proteins(BMPs)initially showed effective induction of ectopic bone growth in muscle,it has since been determined that these proteins,as members of the TGF-b superfamily,play a diverse and critical array of biological roles.These roles include regulating skeletal and bone formation,angiogenesis,and development and homeostasis of multiple organ systems.Disruptions of the members of the TGF-b/BMP superfamily result in severe skeletal and extra-skeletal irregularities,suggesting high therapeutic potential from understanding this family of BMP proteins.Although it was once one of the least characterized BMPs,BMP9 has revealed itself to have the highest osteogenic potential across numerous experiments both in vitro and in vivo,with recent studies suggesting that the exceptional potency of BMP9 may result from unique signaling pathways that differentiate it from other BMPs.The effectiveness of BMP9 in inducing bone formation was recently revealed in promising experiments that demonstrated efficacy in the repair of critical sized cranial defects as well as compatibility with bone-inducing bio-implants,revealing the great translational promise of BMP9.Furthermore,emerging evidence indicates that,besides its osteogenic activity,BMP9 exerts a broad range of biological functions,including stem cell differentiation,angiogenesis,neurogenesis,tumorigenesis,and metabolism.This review aims to summarize our current understanding of BMP9 across biology and the body. 展开更多
关键词 ADIPOGENESIS Bone morphogenetic proteins(BMPs) BMP9/GDF2 Mesenchymal stem cells(MSCs) METABOLISM OSTEOGENESIS Regenerative medicine TUMORIGENESIS
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Hepatitis B virus genotype has no impact on hepatitis B e antigen seroconversion after lamivudine treatment 被引量:21
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作者 Henry Lik-Yuen Chan May-Ling Wong +5 位作者 alex Yui Hui Angel Mei-Ling Chim Ada Mei-Ling Tse Lawrence Cheung-Tsui Hung Francis Ka-Leung Chan Joseph Jao-Yiu Sung 《World Journal of Gastroenterology》 SCIE CAS CSCD 2003年第12期2695-2697,共3页
AIM: To investigate the association of hepatitis B virus (HBV) genotype and HBeAg seroconversion after nucleotide analogue treatment.METHODS: Chronic hepatitis B patients receiving lamivudine followed up for at least ... AIM: To investigate the association of hepatitis B virus (HBV) genotype and HBeAg seroconversion after nucleotide analogue treatment.METHODS: Chronic hepatitis B patients receiving lamivudine followed up for at least 6 months post-treatment were studied. Consecutive treatment-naive patients who were prospectively followed up in the clinic for at least 18 months were studied as controls. HBeAg seroconversion was defined as loss of HBeAg, appearance of anti-HBe and normalization of alanine aminotransferase for at least 6 months.RESULTS: Thirty-five patients on lamivudine and 96 control patients followed up for 39 (18-49) months were studied.Lamivudine was given for 12 (10-18) months, and patients were followed up for 15 (6-34) months after drug cessation.Genotype B and C HBV were found in 43 and 88 patients and HBeAg seroconversion occurred in 12 (28 %) and 16(18 %) patients, respectively (P=0.30). There was no difference in HBeAg seroconversion between patients infected by genotype B and C HBV in the control (35 % vs 21%, P=0.25) and lamivudine-treated (14 % vs 10 %,P=1.00) groups.CONCLUSION: HBeAg seroconversion after treatment by lamivudine was not influenced by the HBV genotype. 展开更多
关键词 乙型肝炎 乙型肝炎病毒 拉米夫定 HBEAG 基因型 抗病毒治疗
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近40年内蒙古候平均气温变化趋势 被引量:19
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作者 裴浩 alex Cannon +1 位作者 Paul Whitfield 郝璐 《应用气象学报》 CSCD 北大核心 2009年第4期443-450,共8页
基于1964—2003年内蒙古有关台站的逐日气温数据,对前20年(1964—1983年)和后20年(1984—2003年)的候平均气温中值进行了对比,并利用k-means方法进行了候平均气温变化趋势的聚类分析,旨在阐明内蒙古气温变化的时空特点和规律。研究结果... 基于1964—2003年内蒙古有关台站的逐日气温数据,对前20年(1964—1983年)和后20年(1984—2003年)的候平均气温中值进行了对比,并利用k-means方法进行了候平均气温变化趋势的聚类分析,旨在阐明内蒙古气温变化的时空特点和规律。研究结果表明:内蒙古全境年平均气温普遍上升,没有下降的现象。不同地区、不同季节气温变化格局不同,北部变暖比南部更为明显,冬季和夏末秋初变暖出现得更频繁。绝大部分地区大多数候平均气温都有所上升,而且候平均气温变化存在纬向地带性。大多数台站四季里都有一些显著升温的候,显著升温在冬季发生得更为频繁。同时,有少数几个候出现气温下降的现象,但未达到显著下降的程度。内蒙古绝大部分地区候最高、最低气温都有所升高,但二者的差值在缩小。候最低气温出现时间有所提前,候最高气温出现时间有提前也有推迟,但总体上不同地区候最高、最低气温出现时间更加同步。因此,候最高、最低气温的时空均一性有所增强。候最高气温出现时间与候最低气温出现时间的间隔有扩大迹象。总之,全球气候变暖降低了气温的季节和地区差异。 展开更多
关键词 气温变化 候平均气温 聚类分析 内蒙古
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基于TPB和VBN的低碳旅游生活行为影响因素研究模型构建初探 被引量:17
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作者 黄雪丽 路正南 Yasong (alex) WANG 《科技管理研究》 CSSCI 北大核心 2013年第21期181-190,共10页
在文献研究和对旅游活动的特点分析的基础上,提出了低碳旅游生活行为意愿、低碳旅游生活行为态度、主观规范、知觉行为控制、习惯、旅游中的情境、悠逸诉求可能影响低碳旅游生活行为,在计划行为理论和价值-信念-规范理论为理论框架下构... 在文献研究和对旅游活动的特点分析的基础上,提出了低碳旅游生活行为意愿、低碳旅游生活行为态度、主观规范、知觉行为控制、习惯、旅游中的情境、悠逸诉求可能影响低碳旅游生活行为,在计划行为理论和价值-信念-规范理论为理论框架下构建了"低碳旅游生活行为影响因素分析模型",并为模型中的潜变量观测变量设计了测量题项。 展开更多
关键词 低碳旅游 生活行为 影响因素 分析模型
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内毒素诱导大鼠葡萄膜炎的组织平片和切片研究 被引量:16
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作者 杨培增 alex F. de Vos +1 位作者 Lidy Broersma Aize kijlstra 《中华眼底病杂志》 CAS CSCD 1996年第1期33-36,共4页
目的:探讨内毒素诱导的视网膜脉络膜改变和平片、切片结果的差异。方法:从内毒素注射的Lewis鼠制备视网膜和脉络膜-巩膜复合体平片以及眼组织冰冻切片,并进行免疫组织化学染色。结果:平片上显示,注射后4小时单核细胞浸润,随后,大量的单... 目的:探讨内毒素诱导的视网膜脉络膜改变和平片、切片结果的差异。方法:从内毒素注射的Lewis鼠制备视网膜和脉络膜-巩膜复合体平片以及眼组织冰冻切片,并进行免疫组织化学染色。结果:平片上显示,注射后4小时单核细胞浸润,随后,大量的单核巨噬细胞浸润至整个视网膜和脉络膜,脉络膜中尚有MHC-Ⅱ类抗原阳性细胞增多;切片上发现,于注射后一定时期,视网膜和脉络膜中有上述细胞浸润。结论:平片技术为视网膜脉络膜原发性严重受累提供了确凿的证据,内毒素诱导的葡萄膜炎可作为人类全葡萄膜炎的动物模型。 展开更多
关键词 内毒素 葡萄膜炎 病理学 免疫组织化学
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Impacts of Weather Conditions Modified by Urban Expansion on Surface Ozone: Comparison between the Pearl River Delta and Yangtze River Delta Regions 被引量:17
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作者 王雪梅 陈飞 +4 位作者 吴志勇 张美根 Mukul TEWARI alex GUENTHER Christine WIEDINMYER 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2009年第5期962-972,共11页
In this paper, the online weather research and forecasting and chemistry (WRF-Chem) model is used to explore the impacts of urban expansion on regional weather conditions and its implication on surface ozone concent... In this paper, the online weather research and forecasting and chemistry (WRF-Chem) model is used to explore the impacts of urban expansion on regional weather conditions and its implication on surface ozone concentrations over the Pearl River Delta(PRD) and Yangtze River Delta(YRD) regions. Two scenarios of urban maps are used in the WRF-Chem to represent the early 1990s (pre-urbanization) and the current urban distribution in the PRD and the YRD. Month-long simulation results using the above land-use scenarios for March 2001 show that urbanization increases both the day- and night-time 2-m temperatures by about 0.6℃and 1.4℃, respectively. Daytime reduction in the wind speed by about 3.0 m s-1 is larger than that for the nighttime (0.5 to 2 m s-1). The daytime increase in the PBL height (〉 200 m) is also larger than the nighttime (50-100 m). The meteorological conditions modified by urbanization lead to detectable ozone-concentration changes in the PRD and the YRD. Urbanization increases the nighttime surface-ozone concentrations by about 4.7%-8.5% and by about 2.9%-4.2% for the daytime. In addition to modifying individual meteorological variables, urbanization also enhances the convergence zones, especially in the PRD. More importantly, urbanization has different effects on the surface ozone for the PRD and the YRD, presumably due to their urbanization characteristics and geographical locations. Even though the PRD has a smaller increase in the surface temperature than the YRD, it has (a) weaker surface wind speed, (b) smaller increase in PBL heights, and (c) stronger convergence zones. The latter three factors outweighed the temperature increase and resulted in a larger ozone enhancement in the PRD than the YRD. 展开更多
关键词 URBANIZATION Pearl River Delta (PRD) Yangtze River Delta (YRD) surface ozone concentrations WRF-Chem
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Clinical effects of three types of silicone intubations in repairing lacerations of canaliculus 被引量:16
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作者 潘晓晶 alex Mao +2 位作者 赵桂秋 孟旭霞 杨珊珊 《Chinese Journal of Traumatology》 CAS 2009年第3期173-176,共4页
Objective: To evaluate the clinical effects of onepassage, double-passage and circular canalicular intubations in repairing lacerations of canaliculus. Methods: Atotal of 109 eyes in 109 cases ofcanalicular lacerat... Objective: To evaluate the clinical effects of onepassage, double-passage and circular canalicular intubations in repairing lacerations of canaliculus. Methods: Atotal of 109 eyes in 109 cases ofcanalicular laceration were repaired with three types of silicone intubations, among which 23 with one-passage canalicular intubation, 51 with double-passage canalicular intubation, and 35 with circular canalicular intubation. The average follow-up period was 12-15 months. Results: The wound/junction of the lacrimal canaliculi was ruptured in 5 cases (9.80%) of the double-passage group, 3 cases (8.57%) of the circular group, and 8 cases (34.78%) of the one-passage group. The rupture incidence of the one-passage group was significantly higher than that of the other two groups ( χ^2=9.416, P〈0.01). During the inmbation, canaliculitis was observed in 12 cases (23.53%) of the double-passage group, while only 3 cases (8.57%) in the circular group and 8 cases (34.78%) in the one-passage group. The circular group had significantly lower incidence of canaliculitis than the other two groups ( χ^2=6.095, P〈0.05). After extubation 6 months after laceration repair, the lacrimal passage remained patent with canalicular irrigation in 46 cases (90.20%) in the double-passage group, 30 cases (85.71%) in the circular group and 15 cases (65.22%) in the one-passage group. Six months after surgery, the canalicular patency in the one-passage group was significantly lower than that of the other two groups ( χ^2=7.390, P〈0.05). Conclusions: Circular canalicular intubation is more stable and has less surgical complications than the doublepassage and one-passage canalicular intubations. It is also more effective clinically 12-15 months after laceration surgery. 展开更多
关键词 Lacrimal apparatus INTUBATION Wounds and injuries
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倾向得分法综述 被引量:15
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作者 alex Z Fu 唐艳 陈刚 《中国药物经济学》 2008年第2期27-34,共8页
倾向得分是在给定观察变量前提下接受干预的条件概率。倾向得分法试图通过准随机过程来去除比较组与其他观察因素的混杂效应。本文首先把倾向得分法与随机选择及标准匹配技术进行了比较。然后描述了倾向得分法的实际应用。第一阶段是建... 倾向得分是在给定观察变量前提下接受干预的条件概率。倾向得分法试图通过准随机过程来去除比较组与其他观察因素的混杂效应。本文首先把倾向得分法与随机选择及标准匹配技术进行了比较。然后描述了倾向得分法的实际应用。第一阶段是建立倾向得分模型,第二阶段就应用倾向得分去评价研究结果。最后本文对倾向得分的优劣势进行了讨论。 展开更多
关键词 协变量 干预效果 分法 倾向 得分 回归模型 条件概率 对照组 配对 因果效应
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