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Radiochemical separation of thorium from ^(18)O inducedreaction with natural uranium

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Nuclear Science and Techniques 2001年第2期12卷 81-86页

作者： yanG Wei-Fan, YUAN Shuang-Gui, XIONG bing, XU yan-bing, HE jian-Jun, PAN Qiang-yan, MA Tao-Tao Institute of Modern Physics, the Chinese Academy of Sciences, Lanzhou 730000 中科院近代物理所甘肃兰州 730000

A radiochemical procedure used to separate and purify trace concentration thorium produced in heavy ion reaction with uranium targets is presented. The procedure can rapidly yield thorium fraction suitable for gamma-ray spectroscopy studies. The resultant gamma-ray spectra showed that Th was isolated from a large number of elements produced in the reaction, and there were only a few contaminating activities of isotopes of Sc, Cd, In, etc. The decontamination factors for the main reaction products are given.

关键词：钍放射化学分离天然铀

The effects of soil properties, cropping systems and geographic location on soil prokaryotic communities in four maize production regions across China

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Journal of Integrative Agriculture 2022年第7期21卷 2145-2157页

作者： TIAN Xue-liang LIU Jia-jia LIU Quan-cheng XIA Xin-yao PENG Yong Alejandra I.HUERTA yan jian-bing LI Hui LIU Wen-de State Key Laboratory for Biology of Plant Diseases and Insect Pests Institute of Plant ProtectionChinese Academy of Agricultural SciencesBeijing 100193P.R.China Henan Engineering Research Center of Biological Pesticide&Fertilizer Development and Synergistic Application Henan Institute of Science and TechnologyXinxiang 453003P.R.China School of Biological Science and Technology University of JinanJinan 250022P.R.China National Key Laboratory of Crop Genetic Improvement Huazhong Agricultural UniversityWuhan 430070P.R.China Department of Entomology and Plant Pathology North Carolina State UniversityRaleigh 27606USA

The diversity of prokaryotic communities in soil is shaped by both biotic and abiotic ***,little is known about the major factors shaping soil prokaryotic communities at a large scale in *** this end,we undertook a study to investigate the impact of maize production cropping systems,soil properties and geographic location(latitude and longitude)on soil prokaryotic communities using metagenomic techniques,across four distinct maize production regions in *** all study sites,the dominant prokaryotes in soil were Alphaproteobacteria,Gammaproteobacteria,Betaproteobacteria,Gemmatimonadetes,Acidobacteria,and ***-metric multidimensional scaling revealed that prokaryotic communities clustered into the respective maize cropping systems in which they *** analysis(RDA)showed that soil properties especially pH,geographic location and cropping system jointly determined the diversity of the prokaryotic *** functional genes of soil prokaryotes from these samples were chiefly influenced by latitude,soil pH and cropping system,as revealed by RDA *** abundance of genes in some metabolic pathways,such as genes involved in microbe–microbe interactions,degradation of aromatic compounds,carbon fixation pathways in prokaryotes and microbial metabolism were markedly different across the four maize production *** study indicated that the combination of soil pH,cropping system and geographic location significantly influenced the prokaryotic community and the functional genes of these *** work contributes to a deeper understanding of the composition and function of the soil prokaryotic community across large-scale production systems such as maize.

关键词： metagenome cropping system maize soil prokaryotes

Safety and efficacy of coronary drug eluting stent for atherosclerotic stenosis of the small renal artery

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Chinese Medical Journal 2009年第10期122卷 1223-1226页

作者： LI Chun-jie WU Zheng yan Hong-bing WANG jian ZHAO Han-jun The 28th Division Beijing Anzhen Hospital Capital Medical University Beijing 100029 China

Small diameter renal artery refers to the renal artery with the cross-section diameter less than 5 mm, the incidence of which is approximately 8%＇ Small diameter renal artery is common in patients with congenital multi-branch renal arteries, diabetes and multi-coronary artery lesions. Renal artery bare-mental stent （BMS） implantation is the standard treatment for ostial renal

关键词： drug eluting stent atherosclerotic stenosis small renal artery

Anti-ageing effects of a new Dimethylaminoethanol-based formulation on DGalactose induced skin ageing model of rat

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中国美容医学 2015年第5期24卷 1-8页

作者： yan bing-jian YUAN Feng ZHAO Cai-ling LIU Su Department of burn and Plastic Surgery The Affiliated Hospital of Medical SchoolQingdao University School of Medicine Qingdao University Technical Director Beijing Biodegradable Materials Engineering Laboratory Department of Burn and Plastic Surgery Laiwu People's Hospital Department of Plastic and Aesthetic Surgery The Affiliated Hospital of Medical SchoolQingdao University

Background Dimethylaminoethanol has been widely used to fight against wrinkles, in the field of aesthetic medicine there is an increasing demand for safe and effective Dimethylaminoethanol-based products to counteract the ageing process. Objective To evaluate the anti- ageing effects of a new DMAE- based formulation. Methods 30 male rats were randomly allocated into treatment,D-gal ageing modeland control groups, each of which contained ten *** group and D- gal ageing model group were subcutaneously injected with D- galactose prepared in normal saline 125mg·kg-1·d-1for 42 d. Control groups were injected with normal saline for42 d with same method and dose. From the 18 th day,after shaving their hair,the treatment grouprats were injected thisnew DMAE-based formulation at a dose of 1ml per week for 4 weeks in the Dermis of two sides hip skin mark ***,D-gal ageing model group rats were administrated the same volume of normal saline with same method. Skin specimens were obtained 3days after the last treatment. Dermal collagen density and dermal thickness were evaluated by H&E and Massontrichrome staining. And m RNA expressions of TGFβ1, Smad3, Type I,Type III Pro-collagen,TIMP-1,MMP- 1,were assessed by Real- time quantitative polymerase chain reaction. Results Dermal thickness, dermal collagen density and hydroxyproline content in treatment group increased significantly comparing with D- gal ageing model group. No differences were found in m RNA expression of MMP- 1 and Type III Pro- collagen between the treatment group and D- gal ageing model group. In addition, m RNA expression of TGFβ1, Type I Pre-collagen, TIMP1 and smad3 in treatment group were significantly up- regulated in contrast with D- gal ageing model and control group. Conclusion This new DMAE- based formulationcould generate anti- ageing effects by activating collagen synthesisthrough TGF-β1/Smads signaling pathway.

关键词： anti-ageing TGF-β1/Smads signaling pathway Dimethylaminoethanol

Frequency of infarct-related artery with myocardial bridging in patients with ST-elevation myocardial infarction and its impact upon percutaneous coronary intervention

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Chinese Medical Journal 2006年第7期119卷 539-543页

作者： yan Hong-bing WANG jian ZHU Xiao-ling GAO Hal LI Nan AI Hui Center for Heart Lung and Blood Vessel DiseasesAnzhen Hospital Capital University of Medical Sciences Beijing100029 China

Background Myocardial bridging （MB） as a congenital condition with a reported frequency of 5%-12% in diagnostic coronary angiography may be an important factor causing myocardial ischemia. However, its frequency in the infarct-related artery （IRA） of patients with ST-elevation myocardial infarction （STEMI） and the impact upon percutaneous coronary intervention （PCI） remain undetermined. In this study, we investigated MB frequency and its impact upon primary PCI in patients with STEMI. Methods The data of coronary angiography for 554 consecutive patients with STEMI who had undergone successful primary PCI were retrospectively analyzed to identify a frequency of MB in the IRA and its association with gender and age. According to the angiographic findings, the patients were divided into MB patients and non-MB patients. The endpoints of this study included immediate angiographic findings after primary PCI and 6-month major adverse cardiac events （MACE）（death, recurrent myocardial infarction, target lesion or vessel revascularization） between the MB patients and the non-MB patients. Results A frequency of MB in the IRA of 46 patients （8.3%） was identified in this series; it was more common in patients ≥65 years old （36/206） than in those 〈65 years old （10/348）（17.5% vs 2.9%, P〈0.001）. The trend of MB in the IRA was observed more frequently in women without significant difference than in men （10.2% vs 7.8%）. TIMI grade Ⅲ flow was achieved in 91.9% （509/554） of all patients following primary PCI, in 60.9% （28/46） of the MB patients and in 94.7% （481/508） of the non-MB patients respectively （P〈0.001）. The in-hospital mortality was 4.7% （26/554） in this series including 13.0% （6/46） of the MB patients and 3.9% （20/508） of the non-MB patients （P〈0.001）. A significant difference in 6 months MACE was seen between the MB patients （19%） and the non-MB patients （6.2%）（P〈0.001）. Conclusions MB in the IRA is relatively common in elderly patients with STEMI with a more evide

关键词： myocardial bndging myocardial infarction percutaneous coronary intervention

玉米起源进化的“世纪之争”——且看技术进步和学科交叉如何解决重大科学问题

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玉米科学 2023年第6期31卷 1-6页

作者：严建兵华中农业大学/作物遗传改良全国重点实验室/湖北洪山实验室武汉430070

玉米作为世界种植最为广泛的作物之一,其起源问题一直争议不断。主要有两个假说,一个是保罗·芒格尔斯多夫提出的“三成分起源说”,另一个是乔治·比德尔提出的“大刍草单一起源假说”。分子生物学技术的发展,为单一起源假说提供了直接... 详细信息

玉米作为世界种植最为广泛的作物之一,其起源问题一直争议不断。主要有两个假说,一个是保罗·芒格尔斯多夫提出的“三成分起源说”,另一个是乔治·比德尔提出的“大刍草单一起源假说”。分子生物学技术的发展,为单一起源假说提供了直接证据,从而得到了科学界的共识。随着科学技术不断进步,许多研究发现,玉米的大刍草单一起源假说存在诸多解释不通的现象。综合利用考古学、分子生物学、群体遗传学等研究手段,中美学者联合提出了玉米起源的新模型,即“二次起源假说”。约9 000年前,玉米单一起源于小颖大刍草亚种;6 000年前后,玉米又与墨西哥高原亚种发生了一次杂交,发生了第二次驯化,现代玉米都是来自两个不同大刍草的后代。二次起源极大地提高了现代玉米的适应性,墨西哥高原亚种为现代玉米提供了高原适应性和广泛的抗性基因,这为今天玉米成为全球适应性最广和种植面积最大的作物奠定重要的物质基础。该模型为理解人为机制对作物驯化起源的影响提供了良好范例,并为利用野生资源进行作物遗传改良奠定重要理论基础。

关键词：玉米大刍草起源

竹木家具进出口贸易报关过程中税收法律问题探讨

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林产工业 2020年第2期57卷 104-106页

作者：严剑冰河南机电职业学院

在经济全球化的大趋势下,中国竹木家具进出口贸易发展迅速。从竹木家具进出口贸易报关过程中实际税收问题入手,深入分析了竹木家具进出口贸易税收方面存在的问题,并对竹木家具进出口贸易报关过程中的法律问题提出了针对性建议。

关键词：竹木家具进出口贸易现状税收法律问题建议

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密植高产——我国玉米育种的最核心目标

生物技术通报 2023年第8期39卷 1-3页

作者：严建兵赵久然华中农业大学作物遗传改良全国重点实验室北京市农林科学院玉米研究所玉米DNA指纹及分子育种北京市重点实验室

我国是人口大国，粮食安全是事关国家长治久安的重大战略问题。习近平总书记指出，中国人的饭碗任何时候都要牢牢端在自己手上。至2050年，全球人口将突破90亿，预计全球作物产量需要再提高一倍才能满足需求。在耕地资源日趋紧张、极端... 详细信息

我国是人口大国，粮食安全是事关国家长治久安的重大战略问题。习近平总书记指出，中国人的饭碗任何时候都要牢牢端在自己手上。至2050年，全球人口将突破90亿，预计全球作物产量需要再提高一倍才能满足需求。在耕地资源日趋紧张、极端气候和病虫害频发的形势下，继续提升粮食产量的关键在于提升单产水平。玉米是全球重要的粮食、饲料和能源作物，对保障世界粮食安全意义重大。

关键词：密植高产玉米育种极端气候

Diver CE versus Guardwire Plus for thrombectomy in patients with inferior myocardial infarction:a trial of aspiration of thrombus during primary angioplasty for inferior myocardial infarction

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Chinese Medical Journal 2007年第7期120卷 557-561页

作者： yan Hong-bing WANG jian LI Nan ZHU Xiao-ling GAO Hai AI Hui LI Xiang YE Ming CHI Yun-peng ZHANG Hong Emergency Center for Heart Lung and Vessel Diseases Beijing Anzhen Hospital Capital University of Medical Sciences Beijing 100029 China

Background Different feasible and safe thrombectomy and distal protection devices have been used in clinical practice. The efficiency and safety of adjunct thrombectomy using Diver CE device （Invatec, Italy） versus Guardwire Plus device （Medtronic, USA） before percutaneous coronary intervention （PCI） were compared in patients with acute inferior ST-segment-elevation myocardial infarction （STEMI） for less than 12 hours, thrombolysis in myocardial infarction （TIMI） flow grade 0 to 1, and total occlusion of the proximal right coronary artery （≥3 mm in diameter） in a prospective randomized single-center study. Methods The primary end point was the magnitude of ST-segment resolution （STR）（〉70%） measured immediately, 90 minutes and 6 hours after PCI, myocardial blush grade and slow flow or no-reflow. Secondary end points were left ventricular end-diastolic volume （LVEDV）, left ventricle ejection fraction （LVEF） and major adverse cardiac events （MACEs） including death, myocardial infarction, target vessel revascularization and stroke at 30 days. Results A total of 122 patients were equally divided into Diver CE group and Guardwire Plus group, which were comparable by age （（60±14） years vs （60±13） years）, male （82% vs 84%）, diabetes （31% vs 28%）, previous coronary artery disease （25% vs 23%）, onset-to-angiogram （（350±185） min vs （345±180） min）, and use of glycoprotein lib/llia inhibitor （11% vs 13%）. The magnitude of ST-segment resolution was similar in the two groups as ST-segment resolution 〉70% （57% vs 59%; P〉0.05）. Similar slow flow/no-reflow rates were observed in the Diver CE group （8%） and the Guardwire Plus group （7%）. TIMI flow grade 3 was obtained in 95% vs 97% patients, respectively （P〉0.05）. Myocardial blush grade 3 was similar （70% vs 72%; P〉0.05）. Thirty-day clinical outcome was comparable （LVEF, 0.54±0.12 vs 0.53 ±0.11; death, 3% vs 3%; myocardial infarction, 2% vs 0%; and target vessel revascularization, 2% vs 2%; P〉0.05, respectively）. Conclusions Re

关键词： acute myocardial infarction stenting thrombectomy devices