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61.
Qi WANG Xiaoxia SHEN Tian QIU Wei WU Lin LI Zhi'an WANG Huixia SHOU 《Journal of Zhejiang University. Science. B》2021,22(2):99
Nucleic acids in plant tissue lysates can be captured quickly by a cellulose filter paper and prepared for amplification after a quick purification.In this study,a published filter paper strip method was modified by sticking the filter paper on a polyvinyl chloride resin(PVC)sheet.This modified method is named EZ-D,for EASY DNA extraction.Compared with the original cetyl trimethylammonium bromide(CTAB)method,DNA extracted by EZ-D is more efficient in polymerase chain reaction(PCR)amplification due to the more stable performance of the EZ-D stick.The EZ-D method is also faster,easier,and cheaper.PCR analyses showed that DNA extracted from several types of plant tissues by EZ-D was appropriate for specific identification of biological samples.A regular PCR reaction can detect the EZ-D-extracted DNA template at concentration as low as 0.1 ng/μL.Evaluation of the EZ-D showed that DNA extracts could be successfully amplified by PCR reaction for DNA fragments up to 3000 bp in length and up to 80%in GC content.EZ-D was successfully used for DNA extraction from a variety of plant species and plant tissues.Moreover,when EZ-D was combined with the loop-mediated isothermal amplification(LAMP)method,DNA identification of biological samples could be achieved without the need for specialized equipment.As an optimized DNA purification method,EZ-D shows great advantages in application and can be used widely in laboratories where equipment is limited and rapid results are required. 相似文献
62.
Bridging western and First Nations thought: Balanced education in Whitehead's philosophy of organism and the sacred circle 总被引:1,自引:0,他引:1
Robert Regnier 《Interchange》1995,26(4):383-415
The sacred circle offers a perspective for interpreting and theorizing about human development valuable in shaping the education of First Nations and non-First Nations students. For those of us in a western materialist culture who are interested in coming to understand what the sacred circle might offer, it is necessary to address assumptions in our own culture. This paper proceeds in four parts to facilitate such an understanding. Part One formulates the importance of a culturally self-critical approach to understanding education based in the sacred circle. Part Two presents the sacred circle as a pattern used to interpret meaning in First Nations education. Part Three examinesinterconnectedness through (a) whitehead's criticism of western scientific epistemology and his idea of education for balanced development, and (b) through the creator, mother earth and the Four Directions reflected in the sacred circle. Part Four interprets aholistic apprehension approach to education based in (a) Whitehead's notion's of intuition and imagination for balanced development from the sacred circle perspective, and (b) through the sacred circle in the vision quest ceremony. 相似文献
63.
Regulatory policy as innovation: Constructing rules of engagement for a technological zone of tissue engineering in the European Union 总被引:2,自引:0,他引:2
Alex Faulkner 《Research Policy》2009,38(4):637-646
This paper addresses the question of the part that regulation plays in processes of innovation in sectors of technology. The politico-economic phenomenon of ‘Europe’ is partly constituted by regulatory regime-building, and new technologies are one of the major sites of regime-building. A constructionist social theory perspective shows that study of the conflictual processes of regulatory policymaking affords insights into the formation of the rules of engagement that constitute technology domains. Adopting the concept of emergent ‘technological zone’ in preference to industrial ‘sector’ or technoscientific network, the paper presents, using empirical research, a detailed account of the case of the debate and development of regulatory policy for therapeutic tissue engineering in the European Union's policy institutions and stakeholder networks. It describes how the jurisdiction of an emergent zone has been formed through such negotiations, providing a counter-example to the common view that regulation ‘lags behind’ innovation. The analysis takes account particularly of the part played by the malleability of the definition of the material technology itself in such constructive governance processes, and it also suggests various consequences for the array of producers of the technology, for market structuring and for the innovation pathways taken by tissue engineering technology. Concluding, the paper argues that there is conceptual advance to be made by bringing together constructionist social theory with innovation studies approaches that highlight the part played by non-firm, public institutions in shaping innovation ecologies. 相似文献
64.
BackgroundLycium barbarum (also called wolfberry), a famous Chinese traditional medicine and food ingredient, is well recognized for its significant role in preventing obesity; however, the molecular mechanisms underlying its preventive effects on fat accumulation are not well understood yet. The aim of this study was to determine the effects and mechanism of Lycium barbarum polysaccharides (LBP) on the proliferation and differentiation of 3T3-L1 preadipocytes. MTT was used to detect the proliferation of 3T3-Ll preadipocytes. Oil red O staining and colorimetric analysis were used to detect cytosolic lipid accumulation during 3T3-L1 preadipocyte differentiation. Real-time fluorescent quantitative PCR (qPCR) technology was used to detect peroxisome proliferator-activated receptor γ (PPARγ), CCAAT/enhancer-binding protein α (C/EBPα), adipocyte fatty-acid-binding protein (aP2), fatty acid synthase (FAS), and lipoprotein lipase (LPL) expression.ResultsThe concentration of LBP from 25 to 200 μg/mL showed a tendency to inhibit the growth of preadipocytes at 24 h, and it inhibited the differentiation of 3T3-L1 preadipocytes in a dose-dependent manner. In the preadipocytes treated with 200 μg/mL LBP, there were reduced lipid droplets in the cytoplasm, and its effect was opposite to that of rosiglitazone (ROS), which significantly reduced the PPARγ, C/EBPα, aP2, FAS, and LPL mRNA expression of adipocytes.ConclusionsLBP exerts inhibitive effects on the proliferation and differentiation of 3T3-L1 preadipocytes and decreases the cytoplasm accumulation of lipid droplets during induced differentiation of preadipocytes toward mature cells. Above phenomenon might link to lowered expression of PPARγ, C/EBPα, aP2, FAS, and LPL after LBP treatment. Thus, LBP could serve as a potential plant extract to treat human obesity or improve farm animal carcass quality via adjusting lipid metabolism.How to cite: Xu X, Chen W, Yu S, et al. Inhibition of preadipocyte differentiation by Lycium barbarum polysaccharide treatment in 3T3-L1 cultures. Electron J Biotechnol 2021;50. https://doi.org/10.1016/j.ejbt.2021.01.003 相似文献
65.
66.
葛涛 《扬州职业大学学报》2011,15(3):9-12
中国传统医药行业很早就进入市场并且有自己的广告传播方式,在医药广告时间和空间的历史演进中经历了由动态到静态,从实物到抽象的各种演变过程,其广告形式也有招幌广告、印刷广告等主要方式.图画广告、名人广告、对联广告、市声广告也在其传播过程中发挥了积极的作用和有益的补充。古代中医药广告形式的探究,对深入研究中国古代医药广告文化、医药商业文化,推动现代医药广告的发展会有积极的作用和帮助。 相似文献
67.
沈国丰 《湖州职业技术学院学报》2010,8(4):28-30
高校二级学院校园文化品牌建设,对于增强学院内部的凝聚力,实现学院的发展具有重要的意义。二级学院校园文化品牌建设的原则应体现大学精神,体现专业特色,体现传承和发展。而具体建设的途径则应包括提升品牌的价值、丰富品牌的精神内涵、加大品牌的培育力度、重视品牌的仪式功能与意义等。 相似文献
68.
唐养璇 《商洛师范专科学校学报》2013,(4):43-46
网目拟地甲以幼虫为害植物的幼嫩根茎而对植物造成危害。针对商洛市商州区2007年以来部分中药材种植园区网目拟地甲发生情况。2009年3月一2010年7月采用大田对角线9点随机采样的方法,对商州区乳河流域丹参、白芍、黄芩、桔梗和金银花15个种植园的网目拟地甲的发生情况进行了调查。结果显示:在丹参、白芍、黄芩、桔梗和金银花5种中药种植园该害虫均有发生但有虫株率差异较大,依次分别(平均)为3.70%、88.49%、1.33%、16.54%和21.67%;说明网目拟地甲在该区域部分中药种植园有选择性发生。 相似文献
69.
黄锋 《广东职业技术师范学院学报》2014,(10):35-40
梳理民族医学与文化体系、生态环境的关系,分析医学人类学的研究路径。“神药两解”现象在今日村庄中依然盛行,村民在遭遇疾病时仍会选择仪式治疗与药物治疗相结合的方式。从当地社会的文化体系与社会关系入手,结合其自然环境与生态环境理解村民的“生病”与“治病”过程,认识特定社会的疾病观念、疾病分类与治疗逻辑。 相似文献
70.
中职畜牧兽医专业实施教育教学优化,是针对中职畜牧兽医专业教育教学存在的一些现实问题提出的有效措施,具有很强的针对性。根据中职畜牧兽医专业实践性较强的特点,对畜牧兽医理论教学和实践教学采取优化措施,可以有效整合教学资源,提高管理效果,对培养学生专业技能有重要意义。 相似文献