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以尴尬为锲机,因势利导;以学定讲,以学定教
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作者 许紫英 《中国校外教育(中旬)》 2014年第9期26-26,106,共2页
预设好的教案,是为了在课堂中得到完美展现。但由于教学进展中的不确定性和非预期性客观存在,这必然要求教学活动突破预期目标和既定教案的限制,而走向生成、开放的创造天地。要求教师充分发挥教学机智,及时调整预设,把握机会,就可以尴... 预设好的教案,是为了在课堂中得到完美展现。但由于教学进展中的不确定性和非预期性客观存在,这必然要求教学活动突破预期目标和既定教案的限制,而走向生成、开放的创造天地。要求教师充分发挥教学机智,及时调整预设,把握机会,就可以尴尬为锲机,以学定讲,以学定教,让课堂更精彩。 展开更多
关键词 学定 学定 圆周率
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从“因需而设”到“以学定教”的理念渗透——小学数学“图形与几何”前置性作业的设计 被引量:4
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作者 林锦 《新教师》 2019年第1期49-50,共2页
生本教育是以学生为中心的教育,笔者觉得其所倡导的教学原则中最重要是以学定教。这就是说,教师应当将学生原有的知识和经验作为教学活动的起点,因此在开始教授新课内容之前,根据学生已具备的知识和生活经验而进行的前置性作业就很有必... 生本教育是以学生为中心的教育,笔者觉得其所倡导的教学原则中最重要是以学定教。这就是说,教师应当将学生原有的知识和经验作为教学活动的起点,因此在开始教授新课内容之前,根据学生已具备的知识和生活经验而进行的前置性作业就很有必要。'图形与几何'知识的学习对于学生引发思维、发展智力、空间观念具有重要意义。然而,在40分钟的课堂中给予学生思考和操作活动的时间是非常有限的. 展开更多
关键词 经验 发展 教育 作业 前置 学生 学定 图形
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少教多学 以学定教——课堂教学中“少教多学”模式初探 被引量:1
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作者 程芙兰 《发展》 2019年第4期90-91,共2页
"少教多学"是就教学要求和教学效果而言的,不同于"先学后教"的先后师生关系和教学顺序,核心意义在于最大限度地减少教师的"教",最大限度地增加学生自主学习时空,让学生成为学习的主人。"以学定教&qu... "少教多学"是就教学要求和教学效果而言的,不同于"先学后教"的先后师生关系和教学顺序,核心意义在于最大限度地减少教师的"教",最大限度地增加学生自主学习时空,让学生成为学习的主人。"以学定教"在学习观上立足于学习者的角度设计课程,强调学习者是课程学习的主体,在教学观上提倡"学路优先",视学生为学习的主体,教师以教促学。本文就"少教多学"的教学模式进行简要的分析探讨。 展开更多
关键词 教学 限度 学定 学习者 课程 学生
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以生为本 以学定教——如何提高初中历史课堂教学的有效性 被引量:1
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作者 王春席 《中国农村教育》 2019年第9期123-123,共1页
随着教育事业的不断发展,课堂教学方式也有很大程度的变化,如何提高初中历史课堂教学的有效性,成为广大初中历史教师应该面对的问题。学生们的初中阶段与他们的青春期相契合,是学生成长的关键阶段。因此,在课堂上对学生们进行正确引导,... 随着教育事业的不断发展,课堂教学方式也有很大程度的变化,如何提高初中历史课堂教学的有效性,成为广大初中历史教师应该面对的问题。学生们的初中阶段与他们的青春期相契合,是学生成长的关键阶段。因此,在课堂上对学生们进行正确引导,使学生们形成正确的历史观,人生观以及价值观,意义非凡。 展开更多
关键词 有效性 学生 课堂教学 教师 学定 发展
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以学定学,师生共创——“一节车厢可以乘坐多少人”项目学习教学设计 被引量:1
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作者 陈家敏 《教学月刊(小学版)(数学)》 2018年第6期23-25,共3页
项目学习是一种以学生为中心的学习模式。在确定研究问题时,尊重学生的基础与需求。师生共同设计研究内容和步骤,共同学习。通过学习内容与学习方式的转变,带来师生的共同成长。
关键词 项目学习 学定 师生共创 学生主体
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以学定学:我国中学地理教学发展新展望——基于全球STEM教育中回归本原的地理教学探析
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作者 钱和玉 陈永堂 《文化创新比较研究》 2018年第25期189-190,192,共3页
以学定学是对过去以学定教的全新理解。本文通过对以学定学内涵及本质的分析解读,统观全球STEM教育发展新趋势下学校教学的新变革,以地理教学为切入点整合以学定学学习方式的回归,探索中学地理教学适应社会发展和全球变革的启示,为中学... 以学定学是对过去以学定教的全新理解。本文通过对以学定学内涵及本质的分析解读,统观全球STEM教育发展新趋势下学校教学的新变革,以地理教学为切入点整合以学定学学习方式的回归,探索中学地理教学适应社会发展和全球变革的启示,为中学地理教学提供可借鉴的探索。 展开更多
关键词 学定 STEM教育 地理教学启示
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“以学定议”:以议题式教学打造高效思想政治课堂
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作者 李辉云 邓燕燕 《中学教学参考》 2022年第7期42-44,共3页
当前,议题式教学在高中思想政治课教学中倍受推崇。议题式教学要求教师从以课程为中心向以学生为中心转变,而要实现这一转变,最重要的是采用“以学定议”的教学策略。具体来说,可以“学”的目标,定“议”的视野;以“学”的起点,定“议... 当前,议题式教学在高中思想政治课教学中倍受推崇。议题式教学要求教师从以课程为中心向以学生为中心转变,而要实现这一转变,最重要的是采用“以学定议”的教学策略。具体来说,可以“学”的目标,定“议”的视野;以“学”的起点,定“议”的策略;以“学”的需要,定“议”的深度;以“学”的发展,定课外拓展。 展开更多
关键词 “以学定议” 议题式教学 思想政治课 核心素养
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基于“以学定学”理念的初中物理复习策略
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作者 陈懋 《理科考试研究》 2019年第10期51-53,共3页
'以学定学'理念下的复习课,通过设置问题唤醒、比较思辨、变式强化,改变以往'以教定学'的被动学习,培养学生核心素养,有效提升解题能力.
关键词 学定 唤醒 思辨 变式
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从“以学定教”到“以学定学”——例谈“友善用脑”理念的实践与探索 被引量:2
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作者 李一婷 《上海教育科研》 CSSCI 北大核心 2013年第5期78-79,共2页
"友善用脑"的理念告诉我们要"以学定学",不但要依据学生的学情来确定教学,更重要的是依据学生的学情来帮助学生主动地学习。南京市东山小学所实践的"友善用脑"课堂教学研究正是相信"所有的学生都是... "友善用脑"的理念告诉我们要"以学定学",不但要依据学生的学情来确定教学,更重要的是依据学生的学情来帮助学生主动地学习。南京市东山小学所实践的"友善用脑"课堂教学研究正是相信"所有的学生都是天生的学习者",努力转变学生的学习方式,实现"轻负担,高质量"的教学效果。本文以《义务教育课程标准实验教科书数学(三年级上册)》第十单元第一课时《认识分数》为例,从自主学习、团队学习、策略运用及评价上介绍了具体的做法。 展开更多
关键词 友善用脑 学定 自学导航 思维导图
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“以学定学”理念下的初中化学复习策略 被引量:1
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作者 陈懋 《中学化学教学参考》 2019年第5期60-62,共3页
如何让复习课中学生不会倦怠情绪泛滥?尝试在"以学定学"理念下进行复习,通过设置自学导航、设置问题情境、开展实验探究、思维可视化,改变以往"以教定学"的被动学习,让学生的学科核心素养、学科观念得以有效提升。
关键词 学定 科学思维 科学用脑 核心素养
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Evaluation of a Novel 32 X-STR Loci Multiplex System in the Forensic Application
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作者 ZHANG Juntao YANG Xingyi +5 位作者 YU Zhengliang ZHAO Peng LIU Dayu HAN Xiaolong SUN Hongyu LIU Chao 《刑事技术》 2024年第5期456-463,共8页
The AGCU X Plus STR system is a newly developed multiplex PCR kit that detects 32 X-chromosomal STR loci simultaneously.These are DXS6807,DXS9895,linkage group 1(DXS10148,DXS10135,DXS8378),DXS9902,DXS6795,DXS6810,DXS1... The AGCU X Plus STR system is a newly developed multiplex PCR kit that detects 32 X-chromosomal STR loci simultaneously.These are DXS6807,DXS9895,linkage group 1(DXS10148,DXS10135,DXS8378),DXS9902,DXS6795,DXS6810,DXS10159,DXS10162,DXS10164,DXS7132,linkage group 2(DXS10079,DXS10074,DXS10075),DXS981,DXS6800,DXS6803,DXS6809,DXS6789,DXS7424,DXS101,DXS7133,GATA172D05,GATA165B12,linkage group 3(DXS10103,HPRTB,DXS10101),GATA31E08 and linkage group 4(DXS8377,DXS10134,DXS7423).A major advantage of this kit is that it takes into account linkage between loci,in addition to detecting more X-STR loci.In order to evaluate the forensic application of 32 X-STR fl uorescence amplifi cation system,PCR settings,sensitivity,species specifi city,stability,DNA mixtures,concordance,stutter,sizing precision,and population genetics investigation were evaluated according to the Scientific Working Group on DNA Analysis Methods(SWGDAM)developmental validation guidelines.The study showed that the genotyping results of each locus were signifi cantly accurate when the DNA template was at least 62.5 pg.Complete profi les were obtained for the 1∶1 and 1∶3 combinations.A total of 209 unrelated individuals from Southern Chinese Han community,consisting of 84 females and 125 males,were selected for population studies,and 285 allele profi les were detected from 32 X-STR loci.The polymorphism information content(PIC)ranged from 0.2721 in DXS6800,to 0.9105 in DXS10135,with an average of 0.6798.DXS10135(PIC=0.9105)was the most polymorphic locus,with discrimination power(DP)of 0.9164 and 0.9871 for the male and female.The cumulative PD_(F),PD_(M),MEC_(trio) and MEC_(duo) valu es were all greater than 0.999999999.There were 78 different DXS10103-HPRTB-DXS10101 haplotypes among the 125 males,and the haplotype diversity was 0.9810.There was no signifi cant difference in the cumulative PD_(F),PD_(M),MEC_(trio) and MEC_(duo) values whether considering linkage or not.In summary,the new X-STR multiplex typing system is effective and reliable,which can be useful in human genetic analysis and kinship testing as a potent complement to autosomal STR typing. 展开更多
关键词 forensic genetics X-STR loci kinship analysis EVALUATION
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Enhancing Na^(+) diffusion dynamics and structural stability of O3-NaMn_(0.5)Ni_(0.5)O_(2)cathode by Sc and Zn dual-substitution
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作者 Bin-bin WANG Yi-ming FENG +8 位作者 Xin LUO Qun HUANG Zi-xing HOU Ya-qin WU Peng-yu WANG Yu-yang QI Qing-fei MENG Wei-feng WEI Liang-jun ZHOU 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2024年第10期3344-3357,共14页
Sc and Zn were introduced into O3-NaMn_(0.5)Ni_(0.5)O_(2)(NaMN)using the combination of solution combustion and solid-state method.The effect of Sc and Zn dual-substitution on Na^(+) diffusion dynamics and structural ... Sc and Zn were introduced into O3-NaMn_(0.5)Ni_(0.5)O_(2)(NaMN)using the combination of solution combustion and solid-state method.The effect of Sc and Zn dual-substitution on Na^(+) diffusion dynamics and structural stability of NaMN was investigated.The physicochemical characterizations suggest that the introduction of Sc and Zn broaden Na^(+) diffusion channels and weaken the Na—O bonds,thereby facilitating the diffusion of sodium ions.Simulations indicate that the Sc and Zn dual-substitution decreases the diffusion barrier of Na-ions and improves the conductivity of the material.The dual-substituted NaMn_(0.5)Ni_(0.4)Sc_(0.04)Zn_(0.04)O_(2)(Na MNSZ44)cathode delivers impressive cycle stability with capacity retention of 71.2%after 200 cycles at 1C and 54.8%after 400 cycles at 5C.Additionally,the full cell paired with hard carbon anode exhibits a remarkable long-term cycling stability,showing capacity retention of 64.1%after 250 cycles at 1C.These results demonstrate that Sc and Zn dual-substitution is an effective strategy to improve the Na^(+) diffusion dynamics and structural stability of NaMN. 展开更多
关键词 layered oxide cathode Sc and Zn dual-substitution structural stability Na^(+)diffusion dynamics
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Ultracytochemical Localization of Acid Phosphatase in Nucellar Cells of Wheat During Degeneration 被引量:6
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作者 田国伟 申家恒 尤瑞麟 《Acta Botanica Sinica》 CSCD 1999年第8期791-794,共4页
The distribution of acid phosphatase activity in nucellar cells of wheat ( Triticum aestivum L.) during degeneration has been studied using the lead precipitation method at the electron microscopic level. Acid phos... The distribution of acid phosphatase activity in nucellar cells of wheat ( Triticum aestivum L.) during degeneration has been studied using the lead precipitation method at the electron microscopic level. Acid phosphatase was localized in the slightly condensed nuclear chromatin in nucellar cells without any sign of ultrastructural degeneration. As the nucellar cells started degenerating, the enzyme activity in the cell was observed, in the order from small vacuoles to cell walls, mitochondria, plastids and endoplasmic reticulum. Enzyme activity was the highest in most components of the nucellar cells adjacent to the embryo sac where the degeneration of nucellar cells was the strongest, but it was not observed in the nuclei of the degenerated nucellar cells. The results indicated that the degeneration of nucellar cells was a progressive and orderly process and supported that the degeneration of nucellar cells was a programmed cell death. 展开更多
关键词 Triticum aestivum Nucellar cell DEGENERATION Acid phosphatase Ultracytochemical localization
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Immunohistochemical Analysis of IAA in Anthers of the Photoperiod-sensitive Genic Male-sterile Rice 被引量:3
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作者 李念华 童哲 卢善发 《Acta Botanica Sinica》 CSCD 2000年第10期1045-1050,共6页
The immunohistochemical localization of IAA and the comparison of their relative levels were carried out for the first time in the anthers of Nongken 58S and its wild type Nongken 58 (Oryza sativa subsp. japonica) af... The immunohistochemical localization of IAA and the comparison of their relative levels were carried out for the first time in the anthers of Nongken 58S and its wild type Nongken 58 (Oryza sativa subsp. japonica) after long_day and short_day treatments. The distribution of free_IAA in anthers and its dynamic variation could be reflected by this method. The results showed that the IAA level in the anthers of Nongken 58S after long_day treatment was much lower than that in short_day_treated Nongken 58S and those in wild type Nongken 58 in five stages from pistil and stamen primordia formation to late uninucleate stage. The possible reasons for IAA deficiency in Nongken 58S_LD anthers and its relationship with fertility alteration were also discussed. 展开更多
关键词 rice anther auxin PHOTOPERIOD male sterility immunohistochemical localization
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Mathematical Definitions of Operators for Cartographic Generalization 被引量:2
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作者 王晓妮 张洁 《Geo-Spatial Information Science》 2003年第1期70-73,共4页
This paper puts forword 11 cartographic generalization operator models and introduces their mathematical definitions,and thus a precise mathematical form and quantitative description has been given to these formerly l... This paper puts forword 11 cartographic generalization operator models and introduces their mathematical definitions,and thus a precise mathematical form and quantitative description has been given to these formerly limited qualitative concepts.The meaning of mathematical definition of operators for cartographic generalization and the application prospect in computer_aided cartography (CAC) is stated.ract The Jurassic strata in Jingyan of Sichuan containing the Mamenchinsaurus fauna are dealt with and divided in this paper. The Mamenchisaurus fossils contained there are compared in morphological features and stratigraphically with other types of the genus on by one. The comprehensive analysis show that the Mamenchisaurus fauna of Jingyan appeared in the early Late Jurassic and is primitive in morphology. The results of the morphological identification and stratigraphical study agree with each other. Their evolutionary processes in different apoches of the Late Jurassic also made clear. Key words Jingyan, Sichuan, Mamenchisaurus Fauna, stratigraphy, evolution 展开更多
关键词 operators for cartographic generalization mathematical definition SELECTION SIMPLIFICATION STRESS
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Immunohistochemical Location of Six Kinds of Endocrine Cell from Digestive Tract of Misgurnus anguillicaudatus 被引量:4
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作者 金显文 黄山 吴孝兵 《Agricultural Science & Technology》 CAS 2009年第1期135-139,共5页
[Objective] The study was to immunohistochemical localize the endocrine cells from digestive tract of Misgurnus [ Method ] Using six gastrointestinal hormone antisera, the endocrine cells from digestive tract of M. an... [Objective] The study was to immunohistochemical localize the endocrine cells from digestive tract of Misgurnus [ Method ] Using six gastrointestinal hormone antisera, the endocrine cells from digestive tract of M. anguillicaudatus was localized. [ Result ]The 5-hydroxytryptamine immunoreactive(5-HT-IR) cells distribute in oesophagus, foregut and midgut; the distribution density was determined to be forepart of foregut 〉 oesophagus and hindpart of foregut 〉 gut, and the differences in the three density gradients reached significant level. Like PP-IR, SS-IR cells were observed mostly in oesophagus, followed by hindpart of foregut, least in forepart of foregut, but never found in gut and hindgut. The three kinds of immunocompetent cells Gas-IR, Glu-IR and SP-IR were not detected in each part of digestive tract. [ Conctusion] This study may provide basic data for studying the nutritional and digestive physiology, as well as the preparation of meridic diets for M. anguillicaudatus. 展开更多
关键词 Misgurnus anguillicaudatus Cantor Digestive tract Endocrine cells IMMUNOHISTOCHEMISTRY
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Taxonomy characterization and cadmium biosorption of fungus strain 被引量:3
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作者 曾晓希 柴立元 +2 位作者 汤建新 刘学端 杨志辉 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2013年第9期2759-2765,共7页
The taxonomy characteriazation and cadmium (Cd) biosorption of the high Cd-resistant fungus M1 were investigated. The internal transcribed spacers (ITS) region and β-tubulin genes of the strain were amplified, se... The taxonomy characteriazation and cadmium (Cd) biosorption of the high Cd-resistant fungus M1 were investigated. The internal transcribed spacers (ITS) region and β-tubulin genes of the strain were amplified, sequenced and analyzed by molecular biology technology. The Cd biosorption assay was performed by shaking flask. Fourier transform infrared spectroscopy was used to analyze the mycelium. The similarity of gene sequences and phylogenetic trees show the very close relation between the strain and Paecilomyces lilacinus, and the fungus M1 was identified as P. Lilacinus. The initial pH 6 and Cd concentration about 100 mg/L are optimum. Zn and Mn have a little effect on the Cd biosorption of the strain, while Cu and Pb present obvious effects. FTIR analysis shows that the fungus adsorbs Cd by esters, anhydride, and amide. With the preferable absorption capacity, fungus M1 is considered to have good prospects in bioremediation. 展开更多
关键词 taxonomy characterization cadmium biosorption Paecilomyces lilacinu Fourier transform infrared spectroscopy
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Preparation of TiO2/Bi2O3 Microfibers and Their Photocatalytic Activity 被引量:1
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作者 马占营 邓玲娟 +1 位作者 李小博 范广 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2014年第4期439-444,J0001,J0002,共8页
A series of TiO2/Bi2O3 heterojunction microfibers have been fabricated using cotton fibers as bio-templates, and characterized by XRD, SEM and UV-Vis techniques. Results reveal that Bi2O3 in the TiO2/Bi2O3 sample is a... A series of TiO2/Bi2O3 heterojunction microfibers have been fabricated using cotton fibers as bio-templates, and characterized by XRD, SEM and UV-Vis techniques. Results reveal that Bi2O3 in the TiO2/Bi2O3 sample is assigned to monoclinic and tetragonal mix-crystal phase. Fibers lengths can reach several micrometers and diameters range from 0.5 μm to 3 μm. Compared with pure TiO2 and Bi2O3, TiO2/Bi2O3 samples display better absorption in visible light region. Photocatalytic activity was evaluated by degradation of MB under visible light irradiation. TiO2/Bi2O3 microfibers exhibite much higher activity than pure TiO2 and Bi2O3, and 22.84%TiO2/Bi2O3 can achieve the decomposition of about 95%MB, which is attributed to synergistic effects of the strong visible-light absorption of TiO2/Bi2O3 microfibers and the heterojunction formed between TiO2 and Bi2O3. 展开更多
关键词 TiO2/Bi2O3 microfiber Visible light HETEROJUNCTION PHOTOCATALYSIS
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Chemical Constituents from Roots of Semiaquilegia adoxoides 被引量:12
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作者 牛锋 谢光波 +2 位作者 崔征 陈发奎 屠鹏飞 《Journal of Chinese Pharmaceutical Sciences》 CAS 2006年第4期251-254,共4页
Semiaquilegia adoxoides ( DC. ) Makino ( Chinese name ''Tian-Kui-Zi'' ) , theonly species of genus Semiaquilegia, belongs to the Ranunculaceae family. As a perennial herbaceousplant, both the aerial pa... Semiaquilegia adoxoides ( DC. ) Makino ( Chinese name ''Tian-Kui-Zi'' ) , theonly species of genus Semiaquilegia, belongs to the Ranunculaceae family. As a perennial herbaceousplant, both the aerial parts and the roots are used in traditional Chinese medicine for differentmedications. The roots are often used to treat inflammation, snake bite, bruises and injuries,tonsillitis, mastitis, scrofula, and cancer for their antibacterial, anti-inflammatory, andantineoplastic activities. The aerial parts are used for the treatment of mastitis, bruises, andheart diseases, such as endomyocarditis. The medicinal usage of this plant prompted us toinvestigate its chemical constituents. As a result, nine compounds 1-9 ( see Figure 1) were isolatedfrom the roots of S. adoxoides. Among them, compounds 1-7 and 9 were isolated from the genusSemiaquilegia for the first time. 展开更多
关键词 Semiaquilegia adoxoides chemical constituents structure determination
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Research Progress of Bactrocera dorsalis and Its Species Complex 被引量:3
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作者 刘建宏 熊小真 +2 位作者 潘涌智 杨丽英 黎小军 《Agricultural Science & Technology》 CAS 2011年第11期1657-1661,共5页
Research progress of B. dorsalis and its species complex in Taiwan region and abroad was summarized from the aspects of classification, origin, transmission, distribution, host, biological characteristics and adaptabi... Research progress of B. dorsalis and its species complex in Taiwan region and abroad was summarized from the aspects of classification, origin, transmission, distribution, host, biological characteristics and adaptability to environmental conditions, in order to provide references and basis for researching B. dorsalis and its species complex in China. 展开更多
关键词 B. dorsalis Species complex IDENTIFICATION Biological characteristics
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