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1甘肃省马铃薯镰刀菌干腐病优势病原的分离鉴定显示文摘为明确甘肃马铃薯镰刀菌干腐病的优势病原,2006年12月~2007年3月由西至东从甘肃张掖、天祝、永登、临洮、渭源和西和等6县市的马铃薯贮藏窖中采集表现有镰刀菌干腐病症状的马铃薯薯块,以组织分离法分离病原,单孢纯化镰刀菌(Fusarium spp.)菌株后,以形态学为基础,参照Nelson镰刀菌分类系统进行鉴定。结果表明:6个采样区共分离到293株镰刀菌菌株,其中以接骨木镰刀菌(F.sambucinum)和茄病镰刀菌(F.solani)出现频率高,是优势种。分析发现第一优势种随采样区而异,张掖、天祝和渭源采集的样品中茄病镰刀菌分离频率分别为42.6%、42.1%和32.4%,接骨木镰刀菌分离频率分别为14.8%、5.3%和26.5%,茄病镰刀菌为第一优势种;永登、临洮和西和采集的样品中接骨木镰刀菌分离频率分别为52.1%、50.9%和55.2%,茄病镰刀菌的分离频率分别为23.3%、32.7%和20.7%,接骨木镰刀菌为第一优势种。本文进一步对其在PDA、CLA上的培养特征进行了观察和描述。按照柯赫氏法则用混合菌株接种法对大西洋(Atlantic)、夏波蒂(Shepody)以及一地方品种进行致病性测定,证实了优势菌种对块茎的致病性。利用EF-1α基因引物(EF-1H和EF-2T)对接骨木镰刀菌菌株GAUF-F12进行基因组DNA的PCR扩增,将PCR产物回收测序后在GenBank上比对,菌株GAUF-F12与GenBank登记的接骨木镰刀菌5个菌株的同源性均达99%;用DNASTAR分析软件将同源性较高的登记菌株的序列与GAUF-F12菌株构建同源性树,结果表明:该菌株与以上5个接骨木镰刀菌菌株均位于同源性树的同一分支,聚为一类,与形态学的鉴定结果一致。李金花 王蒂 柴兆祥 Lester W.Burgess 2011植物病理学报2011,41,5:58
2磺胺甲恶唑和甲氧苄氨嘧啶在土壤中的好氧降解及对微生物呼吸的影响显示文摘实验研究了抗生素药物在不同土壤中(不同种类以及有无添加牛粪)的降解行为,同时采用基质诱导呼吸法考察了药物在土壤中对微生物呼吸的影响.结果表明,添加牛粪的土壤在前20 d内轻微促进了磺胺甲恶唑的降解效率,磺胺甲恶唑的快速降解主要是微生物作用引起,而甲氧苄氨嘧啶则在好氧条件下表现出较强的持久性.同控制土壤样品对比,药物对土壤微生物呼吸的短暂抑制作用出现在前2 d,随后快速恢复.100 d后,在添加不同浓度,单体或混合物的抗生素土壤中,总的矿化程度无较大差异.这表明2种抗生素的不同浓度,单独或混合的添加方式,100 d后对微生物呼吸造成的影响较小.巫杨 陈东辉 SMITH Lester KOOKANA Rai 2011环境化学2011,30,12:13
3黄芪总黄酮对扑热息痛所致肝损伤的防护机理探讨显示文摘目的 :研究黄芪总黄酮对扑热息痛所致肝损伤的防护机理。方法 :用高压液相测定扑热息痛及代谢产物和苯巴比妥诱导睡眠模型研究黄芪总黄酮 (TFA)对扑热息痛的代谢及TFA抗扑热息痛所致损伤的机理。结果 :TFA可明显降低尿中硫醚胺酸的浓度 ,其变化与TFA浓度成反比 ;但对其它代谢产物的影响无明显统计学差异。苯巴比妥诱导小鼠睡眠实验结果显示 ,TFA (10 0mg·kg-1)本身对苯巴比妥代谢无明显影响 (P >0 .0 5 ) ,扑热息痛 (40 0mg·kg-1)可显著延长小鼠的睡眠时间 (P <0 .0 0 1) ;但TFA (10 0mg·kg-1)明显缩短扑热息痛所延长的苯巴比妥诱导的睡眠时间 (P <0 .0 0 5 )。结论汪德清 Critchley Julian AJH 丁保国 马艳青 赵海潞 Thomas G Neil 田亚平 Tomlinson B rian Critchley Lester AH James Anthony Edward 2001中国中药杂志2001,26,9:13
4MoS_2纳米片/CdS纳米线复合光催化剂的制备及其光电化学和光催化活性研究(英文)显示文摘本论文通过两步水热法合成了MoS_2纳米片/CdS纳米线复合光催化剂.采用扫描电子显微镜、透射电子显微镜、X射线粉末衍射仪、拉曼光谱仪、X射线光电子能谱仪、比表面积分析仪、紫外可见漫反射光谱仪、荧光光谱方法和光电化学测试对复合光催化剂进行了表征.研究表明复合光催化剂的性能和MoS_2负载量的多少密切相关.当MoS_2的负载量为5 mol%时复合光催化剂具有最优的光学、光电化学和光催化产氢活性.与纯的CdS纳米线相比,优化后的复合光催化剂以葡萄糖和乳酸为空穴牺牲剂,光电流提高了5.5倍,光催化产氢活性提高了74倍,这主要归因于MoS_2纳米片和CdS纳米线之间的紧密接触有利于提高电荷的分离效率.为了进一步理解光电化学和光催化活性提高的机理,采用瞬态吸收光谱仪深入探究了电荷分离和转移的动力学过程.该工作不仅涉及了具有优良光电化学和光催化活性的复合光催化剂的制备方法,而且展示了葡萄糖在光解水产氢中的应用.王红梅 Sara Bonabi Naghadeh 李春鹤 应露 A’Lester Allen 张金中 2018Science China Materials2018,61,6:9
5儿童游戏的权利--世界范围内游戏在儿童生活中重要性的考察(连载之一)显示文摘本文系统考察世界范围内游戏在儿童生活中重要性,将儿童的游戏权看做1989年联合国《儿童权利公约》(CRC)第31条中的一个独立的权利,旨在为世界范围内和整个联合国《儿童权利公约》框架内探究'儿童的游戏权'提供理论基础,并提出人们为何要承认、尊重儿童游戏权,并阐明将游戏提升为一种儿童权利的理论依据,主张全面深刻理解儿童游戏权利的丰富内涵,特别是作为自我保护方式及作为参与日常生活方法的游戏的社会价值,应积极创设提供儿童游戏发生的条件,努力推进实现儿童的游戏权利。Stuart Lester Wendy Russell 周桂勋 2018陕西学前师范学院学报2018,34,1:9
6Risk factors for colonoscopic perforation: A population-based study of 80118 cases显示文摘AIM: To assess the incidence and risk factors associated with colonic perforation due to colonoscopy. METHODS: This was a retrospective cross-sectional study. Patients were retrospectively eligible for inclusion if they were 18 years and older and had an inpatient or outpatient colonoscopy procedure code in any facility within the Geisinger Health System during the period from January 1, 2002 to August 25, 2010. Data are presented as median and inter-quartile range, for continuous variables, and as frequency and percentage for categorical variables. Baseline comparisons across those with and without a perforation were made using the two-sample t -test and Pearson's χ2 test, as appropriate.RESULTS: A total of 50 perforations were diagnosed out of 80118 colonoscopies, which corresponded to an incidence of 0.06% (95%CI: 0.05-0.08) or a rate of 6.2 per 10000 colonoscopies. All possible risk factors associated with colonic perforation with a P -value < 0.1 were checked for inclusion in a multivariable logbinomial regression model predicting 7-d colonic perforation. The final model resulted in the following risk factors which were significantly associated with risk of colonic perforation: age, gender, body mass index, albumin level, intensive care unit (ICU) patients, inpatient setting, and abdominal pain and Crohn's disease as indications for colonoscopy. CONCLUSION: The cumulative 7 d incidence of colonic perforation in this cohort was 0.06%. Advanced age and female gender were significantly more likely to have perforation. Increasing albumin and BMI resulted in decreased risk of colonic perforation. Having a colonoscopy indication of abdominal pain or Crohn's disease resulted in a higher risk of colonic perforation. Colonoscopies performed in inpatients and particularly the ICU setting had substantially greater odds of perforation. Biopsy and polypectomy did not increase the risk of perforation and only three perforations occurred with screening colonoscopy.Uzair Hamdani Raza Naeem Fyeza Haider Pardeep Bansal Michael Komar David L Diehl H Lester Kirchner 2013World Journal of Gastroenterology2013,19,23:9
7Genotyping-by-sequencing of pear (Pyrus spp.) accessions unravels novel patterns of genetic diversity and selection footprints显示文摘Understanding of genetic diversity and marker-trait relationships in pears(Pyrus spp.)forms an important part of gene conservation and cultivar breeding.Accessions of Asian and European pear species,and interspecific hybrids were planted in a common garden experiment.Genotyping-by-sequencing(GBS)was used to genotype 214 accessions,which were also phenotyped for fruit quality traits.A combination of selection scans and association analyses were used to identify signatures of selection.Patterns of genetic diversity,population structure and introgression were also investigated.About 15000 high-quality SNP markers were identified from the GBS data,of which 25%and 11%harboured private alleles for European and Asian species,respectively.Bayesian clustering analysis suggested negligible gene flow,resulting in highly significant population differentiation(Fst=0.45)between Asian and European pears.Interspecific hybrids displayed an average of 55%and 45%introgression from their Asian and European ancestors,respectively.Phenotypic(firmness,acidity,shape and so on)variation between accessions was significantly associated with genetic differentiation.Allele frequencies at large-effect SNP loci were significantly different between genetic groups,suggesting footprints of directional selection.Selection scan analyses identified over 20 outlier SNP loci with substantial statistical support,likely to be subject to directional selection or closely linked to loci under selection.Satish Kumar Chris Kirk Cecilia Deng Claudia Wiedow Mareike Knaebel Lester Brewer 2017Horticulture Research2017,4,1:8
8Management of low transsphincteric anal fistula with serial setons and interval muscle-cutting fistulotomy显示文摘This study evaluates low transsphincteric anal fistula managed by serial setons and interval fistulotomy, with attention to healing without recurrence and preservation of continence. Following Institutional Review Board approval, consecutive anal fistula operations performed by a single surgeon from January 1, 2009 to December 31, 2013 were retrospectively reviewed using electronic medical records and telephone interviews for patients lost to follow up. Of the 71 patients, 26(37%) had low transsphincteric fistula(23 males and 3 females; mean age: 46 years), treated at our institution by seton placement followed by interval surgical muscle cutting and subsequent seton replacement or final fistulotomy. Of the 26 patients, 22(85%) were initially referred due to previous failed treatment, with a 30.6 month mean duration of fistula prior to referral and a mean of 2.2(range: 0–6) prior anorectal surgeries. At a mean follow-up of 11.9 months, none of the 21 patients experienced recurrence or fecal incontinence. Serial seton with interval muscle-cutting sphincterotomy followed by complete fistulotomy is an effective treatment for the management of patients who are either initially seen for low transsphincteric fistula, or referred after failed anorectal surgery for that condition.Chen Wang Lester Rosen 2016Journal of Integrative Medicine2016,14,2:7
9细胞培养生物制品在不同研发阶段病毒清除的要求显示文摘对纯化工艺的病毒清除验证是确保动物细胞表达的生物制品病毒安全性的重要手段之一。近年来生物制品工业已积累大量单抗纯化工艺中常用纯化步骤病毒清除的数据。基于对这些步骤病毒清除机理和工艺参数影响的深入研究,以及在不同单抗中病毒清除的高重复性,临床用产品可依照国际上病毒安全指导原则来使用模块验证的方法做病毒清除验证。陈琪 张旻 杨滨 Philip Lester 2014中国新药杂志2014,23,8:7
10Antioxidative and anti-endotoxin effects of propofol on endothelial cells显示文摘Objective To investigate the antioxidant and anti-endotoxin effects of propofol on endothelial cells and the possible mechanisms.Methods Cultured endothelial cells were treated with hydrogen peroxide (H 2O 2), propofol + H 2O 2, lipopolysaccharide (LPS) and propofol + LPS, respectively. Endothelial cell damage was monitored for possible lactic dehydrogenase (LDH) release. The transcription and the protein expression levels of endothelial nitric oxide synthase (eNOS) were measured.Results LDH release was higher in groups treated with H 2O 2 or LPS than in the control group. After pretreatment with propofol, the effects induced by H 2O 2 were attenuated, but propofol did not decrease the LDH release induced by LPS. Both H 2O 2 and LPS significantly increased the eNOS transcript levels and the increases were significantly attenuated after pretreatment with propofol. Both H 2O 2 and LPS significantly increased the eNOS protein expression and the increase was attenuated after pretreatment with propofol. Conclusion Propofol could protect endothelial cells against oxidative stress by inhibiting eNOS transcription and protein expression, but could not antagonise endotoxin induced cell injuries.彭志勇 罗敏 叶仕桥 Critchley Lester AH Joynt Gavin M Ho Anthony MH 姚尚龙 2003Chinese Medical Journal2003,,5:7
112004年2月11日Cluster卫星和CUTLASS雷达同时观测的磁通量传输事件显示文摘本文分析了2004年2月11日11:00-11:40UT期间Cluster卫星簇的磁通门磁力计(FGM)、等离子体电子及电流试验仪(PEACE)和CUTLASS芬兰雷达对多个磁通量传输事件(FTEs)的同时观测.在此期间,Cluster卫星簇位于北半球外极隙区附近,并于11:18UT左右穿出磁层顶进入磁鞘,四颗卫星同时观测到了多个FTEs,其出现具有准周期性,周期约为130s.利用Cluster四颗卫星的多点同时观测数据,采用最小方向微分法和时空微分方法,我们推断这些FTEs是尺度大小约为(0.87-1.81)RE的准二维结构,其运动方向为东北方向,与Cooling模型预测方向基本一致.CUTLASS芬兰雷达在相应的电离层区域观测到了明显的"极向运动雷达极光"结构,这些结构与Cluster卫星簇观测的FTEs有着很好的对应关系,它们是FTEs的雷达观测特征.张清和 刘瑞源 黄际英 M. W. Dunlop 胡红桥 胡泽骏 Y. V. Bogdanova M. Lester 2008地球物理学报2008,51,1:6
12The exploitation of epichloae endophytes for agricultural benefit显示文摘Epichloae endophytes of family Clavicipitaceae(comprising genera Epichloëand Neotyphodium)are fungal symbionts of Pooideae grasses.The associations formed,range from mutually beneficial to antagonistic and the nature of this relationship is dependent upon the importance of vertical(via host seeds)versus horizontal(ascospore mediated)transmission of the fungus.These endophytes can enhance their hosts’survival through protection from abiotic and biotic stresses and can thus be utilized in an agricultural context.Animal-safe grass-endophyte associations that confer bio-protective properties for increased pasture persistence and productivity have been developed and commercialized.One of the crucial drivers underpinning the selection of epichloae strains for commercial development is endophyte derived bioactivity.The potential of next generation endophytes is determined by testing a number of attributes such as agronomic fitness,animal and food safety as well as compatibility with host plants of interest.Strategic research supports these activities by focusing on elucidating mechanisms of compatibility between host and fungal symbiont,as well as investigating other molecular drivers of symbiosis such as siderophore mediated iron-uptake,fungal signalling,fungal growth in host plants and fungal secondary metabolism.This review weaves together the different strands of multidisciplinary research aimed at ultimately exploiting epichloae endophytes for increased pasture performance.Linda J.Johnson Anouck C.M.de Bonth Lyn R.Briggs John R.Caradus Sarah C.Finch Damien J.Fleetwood Lester R.Fletcher David E.Hume Richard D.Johnson Alison J.Popay Brian A.Tapper Wayne R.Simpson Christine R.Voisey Stuart D.Card 2013Fungal Diversity2013,,3:5
13SuperDARN CUTLASS Finland radar observations of high-latitude magnetic reconnections under northward interplanetary magnetic field (IMF) conditions显示文摘A number of backscatter power enhancement events with 'equatorward-moving radar auroral forms' in the high-latitude ionosphere were observed by SuperDARN CUTLASS Finland radar when the IMF was northward during 09:00 -10:00 UT on 26 March 2004. These events were also associated with sunward flow enhancements at each location in the Northern Hemisphere which were shown in ionospheric convections measured by the SuperDARN radars. These are typical features of high-latitude (lobe) magnetic reconnections. The durations of the velocity enhancements imply that the evolution time of the lobe reconnections is about 8-16 min from their origin at the reconnection site to their addition to the magnetotail lobe again. In additional, the Double Star TC-1 spacecraft was moving from magnetosheath into magnetosphere, and crossing the magnetopause near the subsolar region during this interval, and observed typical low-latitude magnetic reconnection signatures. This infers that the dayside high- and low-latitude reconnections may occur simultaneously.ZHANG QingHe LIU RuiYuan YANG HuiGen HU HongQiao ZHANG BeiChen DUNLOP Malcolm LESTER Mark BOGDANOVA Yulia WALSH Andrew 2012Science China(Technological Sciences)2012,55,5:5
14Broken Promises: Equity Sensitivity as a Moderator Between Psychological Contract Breach and Employee Attitudes and Behavior显示文摘Jill Kickul Scott W. Lester 2001Journal of Business and Psychology2001,,2:3
15从定期安全性更新报告过渡到定期受益-风险评价报告:初步经验和挑战显示文摘人用药品注册技术要求国际协调会议(ICH)提供了定期安全性更新报告指南(PSUR,ICH E2C(R1))和新的定期受益-风险评价报告指南(PBRER,ICH E2C(R2))。PBRER由PSUR演变而来,实现了从比较传统的获批后药物警戒定期总结报告到现代定期受益-风险评价总结报告的转变,根据累积信息对批准上市产品做出最新的受益-风险评价。通过总结ICH E2C PSUR指南和PBRER指南的主要区别,介绍了某跨国制药公司在由编写PSUR改为编写PBRER的转变过程中所积累的初步经验及其遇到的挑战,讨论了中国在推进药物警戒系统的背景下实行PBRER的可能性。张晓兰 Lester REICH 梁冰 Donald PUCCIO Craig HAR TFORD 2014中国药物警戒2014,11,4:3
16Heparin resistance in severe thermal injury:a prospective cohort study显示文摘Background:Low molecular-weight heparin(LMWH)is routinely administered to burn patients for thromboprophylaxis.Some studies have reported heparin resistance,yet the mechanism(s)and prevalence have not been systematically studied.We hypothesized that nucleosomes,composed of histone structures with associated DNA released from injured tissue and activated immune cells in the form of neutrophil extracellular traps(NETs or NETosis),neutralize LMWH resulting in suboptimal anticoagulation,assessed by reduction in anti-factor Xa activity.Methods:Blood was sampled from>15%total body surface area(TBSA)burn patients receiving LMWH on days 5,10 and 14.Peak anti-factor Xa(AFXa)activity,anti-thrombin(ATIII)activity,cellfree DNA(cfDNA)levels and nucleosome levels were measured.Mixed effects regression was adjusted for multiple confounders,including injury severity and ATIII activity,and was used to test the association between nucleosomes and AFXa.Results:A total of 30 patients with severe burns were included.Mean TBSA 43%(SD 17).Twentythree(77%)patients were affected by heparin resistance(defined by AFXa activity<0.2 IU/mL).Mean peak AFXa activity across samples was 0.18 IU/mL(SD 0.11).Mean ATIII was 81.9%activity(SD 20.4).Samples taken at higher LWMH doses were found to have significantly increased AFXa activity,though the effect was not observed at all doses,at 8000 IU no samples were heparin resistant.Nucleosome levels were negatively correlated with AFXa(r=−0.29,p=0.050)consistent with the hypothesis.The final model,with peak AFXa as the response variable,was adjusted for nucleosome levels(p=0.0453),ATIII activity(p=0.0053),LMWH dose pre-sample(p=0.0049),drug given(enoxaparin or tinzaparin)(p=0.03),and other confounders including severity of injury,age,gender,time point of sample.Conclusions:Heparin resistance is a prevalent issue in severe burns.Nucleosome levels were increased post-burn,and showed an inverse association with AFXa consistent with the hypothesis that they may interfere with the anticoagulant effect of heparin in vivo and contribute to heparin resistance.Accurate monitoring of AFXa activity with appropriate therapy escalation plans are recommended with dose adjustment following severe burn injury.Liam D Cato Benjamin Bailiff Joshua Price Christos Ermogeneous Jon Hazeldine William Lester Gillian Lowe Christopher Wearn Jonathan RB Bishop Janet M Lord Naiem Moiemen Paul Harrison 2021Burns & Trauma2021,9,1:3
17High efficiency synthesis of HKUST-1 under mild conditions with high BET surface area and CO_2 uptake capacity显示文摘This study focuses on the development of a hydrothermal method for the rapid synthesis of good quality copper benzene-1,3,5-tricarboxylate(referred to as HKUST-1)with high yield under mild preparation conditions to address the issues associated with reported methods.Different synthesis conditions and activation methods were studied to understand their influence on the properties of HKUST-1.It was found that mixing the precursors at50°C for 3 h followed by activation via methanol refluxing led to the formation of a product with the highest BET specific surface area of 1615 m^2/g and a high yield of 84.1%.The XRD and SEM data illustrated that the product was highly crystalline.The sample was also tested on its capacity in CO_2 adsorption.The results showed strong correlation between surface area of the sample and its CO_2 uptake at 1 bar and 27°C.The HKUST-1 prepared in this study demonstrated a high CO_2 uptake capacity of 4.2 mmol/g.It is therefore concluded that this novel and efficient method can be used in the rapid preparation of HKUST-1 with high surface area and CO_2 uptake capacity.Yipei Chen Xueliang Mu Edward Lester Tao Wu 2018Progress in Natural Science:Materials International2018,28,5:3
18A clinicopathologic and immunohistochemical study of 35 anaplastic carcinomas of the pancreas with a review of the literature显示文摘Edina Paal Lester D.R. Thompson R.Allen Frommelt Ronald M. Przygodzki Clara S. Heffess 2001Annals of Diagnostic Pathology2001,,3:3
19国际子午圈计划的科学挑战和观测系统显示文摘随着科技发展,人类活动对地面基础设施、空间系统和太空飞行器等高科技设施的依赖性日益增强.然而,这些高科技设施却常常遭受着来自太阳活动、地震、大气和气候变化、地磁场变化,以及全球电场波动等多种危害的威胁.监测和了解这些危害,并减轻其影响,是21世纪重要的科学挑战之一.这些危害尽管形式不同,但是有一个共同之处是会在电离层和中高层大气这个地球空间环境的关键圈层留下自己的印记.国际子午圈计划是一项由中国科学院牵头的国际大科学计划,其目标是整合、部署和运行一个全球研究和监测网络,充分利用电离层和中高层大气的'显示屏'效果来追踪这些日地空间危害的踪迹.文章展示了国际子午圈计划全球观测系统所需的位置分布,即优先沿120°E~60°W大子午圈部署监测设备,实现对主要地理和地磁纬度变化的最佳覆盖,继而辅之以30°E~150°W的第二个子午圈来捕捉经度变化.而后简单地描述了中国子午工程,以及横跨中国、俄罗斯和美洲的一些国家在内的120°E~60°W大子午圈上的监测台站和设备.刘维宁 Michel BLANC 王赤 Eric DONAVAN John FOSTER Mark LESTER Hermann OPGENOORTH 任丽文 2021中国科学:地球科学2021,51,12:3
20Are family firms really superior performers?显示文摘Danny Miller Isabelle Le Breton-Miller Richard H. Lester Albert A. Cannella 2007Journal of Corporate Finance2007,,5:3
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