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改良石蜡切片法观察金针菇子实体不同发育时期组织结构 被引量:4
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作者 王瑞娟 万佳宁 +6 位作者 龚明 茅文俊 汪莹 唐利华 尚俊军 杨慧 鲍大鹏 《食用菌学报》 CSCD 北大核心 2019年第2期54-58,I0008,I0009,共7页
运用改良石蜡切片法制备了金针菇(Flammulina filiformis)子实体不同发育时期的切片,观察其菌褶和菌柄的细胞结构。结果表明,以柠檬烯为透明剂,金针菇子实体组织结构清晰、完整、无皱缩。观察不同发育时期的金针菇子实体组织切片发现,... 运用改良石蜡切片法制备了金针菇(Flammulina filiformis)子实体不同发育时期的切片,观察其菌褶和菌柄的细胞结构。结果表明,以柠檬烯为透明剂,金针菇子实体组织结构清晰、完整、无皱缩。观察不同发育时期的金针菇子实体组织切片发现,金针菇原基内部有呈菌丝无规则扭结状态的菌盖结构,随着子实体不断发育,菌盖下端有菌褶结构分化,随后菌柄结构随菌盖发育而进一步分化,菌柄组织细胞状纵向紧密排列,横切面有维管束状细胞呈外紧密内疏松状排列且其间有孔洞出现,菌褶菌髓部呈菌丝与球泡状细胞共同存在的异型分布结构。 展开更多
关键词 柠檬烯 透明剂 实体组织结构
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人组织因子途径抑制物腺病毒表达系统的构建及体内表达
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作者 邹亚男 李天发 +4 位作者 聂宏刚 张瑶 尹新华 关振中 于波 《中国地方病学杂志》 CAS CSCD 北大核心 2005年第5期575-578,共4页
目的构建携载人组织因子途径抑制物(tissuefactorpathwayinhibitor,TFPI)基因的重组腺病毒载体,为基因治疗提供实验基础。方法利用基因重组技术,将人TFPI基因连接到穿梭质粒pDC316中,然后将腺病毒骨架质粒pBHGlox△E1,3Cre以及重组穿梭... 目的构建携载人组织因子途径抑制物(tissuefactorpathwayinhibitor,TFPI)基因的重组腺病毒载体,为基因治疗提供实验基础。方法利用基因重组技术,将人TFPI基因连接到穿梭质粒pDC316中,然后将腺病毒骨架质粒pBHGlox△E1,3Cre以及重组穿梭质粒pDC316-TFPI共转染293细胞,并在其中发生Cre重组酶介导的位点,特异性重组及腺病毒包装,扩增后进行滴度测定。将包装成功的携带人TFPI基因的重组腺病毒(Ad-TFPI)转染兔颈动脉,并用携带LacZ报告基因的重组腺病毒(Ad-LacZ)作为对照,3d后RT-PCR、ELISA法检测人TFPImRNA、蛋白的表达。结果得到了携带人TFPI基因的重组腺病毒,包装的病毒蚀斑形成单位(plaqueformationunit,PFU)滴度为7.6×1012/L。在Ad-TFPI转染兔颈动脉后3d,RT-PCR法和ELISA法均检测出TFPI表达,Ad-LacZ转染后未测到人TFPI的表达。结论成功构建了人TFPI腺病毒表达载体,为下一步的基因治疗提供了基础。 展开更多
关键词 组织途径抑制物 腺病毒 基因疗法
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组织因子抑制子基因局部转移对兔颈总动脉内膜增生的影响
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作者 朱铁兵 王君 +4 位作者 范乐明 张郁清 曹克将 黄峻 马文珠 《南京医科大学学报(自然科学版)》 CAS CSCD 北大核心 2006年第11期1025-1027,F0002,共4页
目的:研究组织因子抑制子(TFPI)基因局部转移对兔颈总动脉损伤后内膜增生的影响。方法:36只新西兰纯种雄性大白兔随机分为腺病毒空载组,包载组织因子抑制子(TFPI)基因腺病毒组和生理盐水组(每组12只)。用球囊导管对实验兔行颈总动脉损伤... 目的:研究组织因子抑制子(TFPI)基因局部转移对兔颈总动脉损伤后内膜增生的影响。方法:36只新西兰纯种雄性大白兔随机分为腺病毒空载组,包载组织因子抑制子(TFPI)基因腺病毒组和生理盐水组(每组12只)。用球囊导管对实验兔行颈总动脉损伤,术后14天取病变血管,免疫组化染色观察表明TFPI在转移局部表达成功;病变最明显处取标本进行HE染色,光学显微镜下观察血管内膜增生,以计算机图像分析系统分析血管内膜﹑中膜和腔面积的变化,计算内膜增生细胞核抗原增殖指数。结果:TFPI基因局部转移后血管内膜面积明显减少,中膜面积不变,血管腔面积增大。结论:TFPI基因局部转移显著抑制颈总动脉损伤处血管内膜的增生,有可能防治再狭窄。 展开更多
关键词 组织抑制 球囊损伤 内膜增生
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急性冠状动脉综合征患者外周血中脂联素水平与基质金属蛋白酶-9及其组织抑制因子-1关系的探讨 被引量:3
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作者 程敏 曾秋棠 海诗谜 《中国循环杂志》 CSCD 北大核心 2007年第3期180-182,共3页
目的:探讨急性冠状动脉综合征患者(ACS)外周血中脂联素与基质金属蛋白酶-9(MMP-9)及基质金属蛋白酶组织抑制因子-1(TIMP-1)水平及其相关性的研究。方法:急性心肌梗死组19例,不稳定性心绞痛组31例,稳定性心绞痛组13例,正常对照组22例,检... 目的:探讨急性冠状动脉综合征患者(ACS)外周血中脂联素与基质金属蛋白酶-9(MMP-9)及基质金属蛋白酶组织抑制因子-1(TIMP-1)水平及其相关性的研究。方法:急性心肌梗死组19例,不稳定性心绞痛组31例,稳定性心绞痛组13例,正常对照组22例,检测各组外周血中脂联素、MMP-9、TIMP-1的浓度。各组间采用独立样本的t检验,各参数之间进行单因素的相关分析。结果:急性心肌梗死组、不稳定性心绞痛组分别与正常对照组比较:外周血清中脂联素的浓度、TIMP-1的浓度均显著降低(P<0.05~0.01),MMP-9/TIMP-1及MMP-9的浓度则均显著升高(P<0.05~0.01);急性心肌梗死组、不稳定性心绞痛组与稳定性心绞痛组比较,脂联素的浓度显著降低(P<0.05~0.01),MMP-9/TIMP-1升高(P<0.05~0.01);稳定性心绞痛组与正常对照组比较各指标间无明显差异。相关性分析中:脂联素与MMP-9之间无相关性(r=-0.248,P>0.05),脂联素与TIMP-1有显著相关性(r=0.408,P<0.01),脂联素与MMP-9/TIMP-1之间有显著相关性(r=-0.478,P<0.001)。结论:ACS患者中,脂联素的分泌减少,导致TIMP-1的分泌也减少,MMP-9/TIMP-1平衡破坏,可能是急性冠状动脉综合征发生的重要因素。 展开更多
关键词 脂联素 急性冠状动脉综合征 基质金属蛋白酶-9 基质金属蛋白酶组织抑制闪-1
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Chirp-Z变换频谱细化倒谱定征生物软组织散射子平均间距的研究
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作者 郭建中 林书玉 《生物医学工程学杂志》 EI CAS CSCD 北大核心 2007年第6期1378-1381,共4页
用信号处理方法,提取生物软组织声散射特征,从而对生物组是进行鉴别,是超声医学的基础研究一直关注的重要课题,生物软组织的超声散射主要由组织内部的散射子引起,散射子平均间距与组织的微结构特征相关。我们分析和总结了一般基于FFT倒... 用信号处理方法,提取生物软组织声散射特征,从而对生物组是进行鉴别,是超声医学的基础研究一直关注的重要课题,生物软组织的超声散射主要由组织内部的散射子引起,散射子平均间距与组织的微结构特征相关。我们分析和总结了一般基于FFT倒谱,AR倒谱等算法波动性较大、分辨率不高产生的原因,提出利用Chirp-Z变换频谱得到细化倒谱,在超声检测中估计生物软组织散射子平均间距及其变化的新方法,并利用该方法对仿体和生物软组织的回波信号进行了分析。结果表明:该方法是软组织的超声散射信号分析和散射子平均间距定征的一种有效方法。 展开更多
关键词 超声检测 CHIRP-Z变换 倒谱 组织散射平均间距
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组织工程热点子领域中国基础研究实力分析
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作者 陈娟 张婷 +2 位作者 武一丹 卢岩 欧阳昭连 《中国组织工程研究》 CAS 北大核心 2020年第8期1267-1271,共5页
背景:组织工程学发展具有极大的社会价值和经济效益,评估和分析中国在组织工程热点子领域的基础研究实力,将有助于优化资源配置和制定适宜的发展策略。目的:评价中国在组织工程热点子领域的基础研究实力。方法:在PubMed数据库中检索全... 背景:组织工程学发展具有极大的社会价值和经济效益,评估和分析中国在组织工程热点子领域的基础研究实力,将有助于优化资源配置和制定适宜的发展策略。目的:评价中国在组织工程热点子领域的基础研究实力。方法:在PubMed数据库中检索全球、美国和中国在组织工程热点子领域(包括骨和软骨、神经、血管、肝脏、皮肤、心脏、眼组织工程)的基础研究论文和顶尖基础研究论文。以全球和美国为背景,基于论文数量、论文增速、顶尖论文数量及比例,分析中国在组织工程热点子领域的基础研究实力。结果与结论:①中国在骨和软骨组织工程、神经组织工程、血管组织工程、肝脏组织工程、皮肤组织工程、心脏组织工程和眼组织工程领域的基础研究论文数量依次为4487,3551,2869,1328,1185,1088和689篇,占全球发文量的10%-15%之间,其中,前5个子领域的发文量约为美国的一半,心脏组织工程和眼组织工程领域的发文量仅分别为美国的32.1%和37.8%;②中国在上述各子领域的论文量增速分别为19.3%,19.5%,18.2%,14.6%,21.8%,19.6%和19.6%,均远超全球和美国;③中国在上述各子领域的顶尖基础研究论文数依次为36,31,33,24,15,24和12篇,顶尖论文比例依次为0.8%,0.9%,1.2%,1.8%,1.3%,2.2%和1.7%,明显低于全球平均水平和美国;④结果表明,中国在骨和软骨、神经组织工程、血管组织工程3个子领域的基础研究规模相对较大,而在心脏、眼2个子领域的基础研究规模相对较小;中国在各子领域的基础研究规模增速均超过全球和美国,且增速优势明显;中国在各子领域均有一定数量的顶尖基础研究成果,但顶尖成果比例比起全球和美国而言还有较大提升空间。 展开更多
关键词 组织工程 基础研究 研究实力 科技论文 文献计量学 组织工程热点领域
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多层机织物的组织设计 被引量:8
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作者 聂建斌 何奕中 《纺织学报》 EI CAS CSCD 北大核心 2010年第2期50-53,共4页
为有效快速地获得多层接结机织物的设计方法,对多层机织物组织进行研究与分析,找出多层机织物纱线之间的交织规律和表达方法,提出了子组织概念。用这种方法先画出子组织,然后能直接画出多层织物的组织图。在组织图基础上,可较容易进行... 为有效快速地获得多层接结机织物的设计方法,对多层机织物组织进行研究与分析,找出多层机织物纱线之间的交织规律和表达方法,提出了子组织概念。用这种方法先画出子组织,然后能直接画出多层织物的组织图。在组织图基础上,可较容易进行各种不同形式的接结,得到不同效果的纺织增强复合材料预制件,既省时又具有较高准确性。这种方法比较适合用计算机表达,从而为CAD设计多层机织物提供了方便。 展开更多
关键词 多层机织物 组织图设计 子组织 接结组织
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组织行为研究的神经科学进展 被引量:2
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作者 刘童九 唐志文 刘耀中 《商业时代》 北大核心 2013年第5期93-94,共2页
随着神经科学和组织行为学的研究,将神经科学的研究范式结合到组织行为研究中,使得我们从另一个方面更加深入的了解组织行为学中各种现象的生理机制,本文通过当前研究的几个实例来阐述神经科学对组织行为学发展的促进,提供对传统组织研... 随着神经科学和组织行为学的研究,将神经科学的研究范式结合到组织行为研究中,使得我们从另一个方面更加深入的了解组织行为学中各种现象的生理机制,本文通过当前研究的几个实例来阐述神经科学对组织行为学发展的促进,提供对传统组织研究范式新的视角和方法,以期对今后的相关研究有所助益。 展开更多
关键词 组织行为学 神经科学 组织氛围
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Callus Induction and Plant Regeneration from Mature Seeds of Perennial Ryegrass 被引量:15
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作者 曾升坚 卞建春 +2 位作者 方钲 张冬霞 邹新海 《Agricultural Science & Technology》 CAS 2009年第6期33-36,共4页
Objective The aim was to explore callus induction and plant regeneration of perennial ryegrass, as well as provide the foundation for transgenic research on perennial ryegrass.[ Methed] Mature seeds of perennial ryegr... Objective The aim was to explore callus induction and plant regeneration of perennial ryegrass, as well as provide the foundation for transgenic research on perennial ryegrass.[ Methed] Mature seeds of perennial ryegrass were used as explants to study the effects of different hormone compositions on callus induction, proliferation and plant differentiation. Result The result showed that the induction rate achieved its highest on 2,4-D of 8 mg/L combining with 6-BA of 0.025 mg/L, which was up to 56.42%. Callus were differentiated after two to three generations, the highest differentiation rate 34.14% was achieved in the medium contained MS medium with 6-BA of 2 mg/L, and the differentiation rate was obviously affected by the callus condition after proliferation. The root inducing medium, containing 0.5 mg/L NAA and MS medium with half of macroelement, gained 98% root inducing rate. Conclusien A high frequency genetic regeneration system was established. 展开更多
关键词 Perennial ryegrass Mature seed: Tissue culture Plant regeneration
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Micropropagation of Pistacia vera 'Kerman' 被引量:7
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作者 于菲 苏淑钗 +2 位作者 沈漫 姬谦龙 冷平生 《Agricultural Science & Technology》 CAS 2010年第1期107-108,121,共3页
[Objective]The aim was to commercialize micropropagation of pistachio and provide good foundations for varieties improvement. [Method]The seeds and stem-segments were used as explants in the tissue culture of Pistacia... [Objective]The aim was to commercialize micropropagation of pistachio and provide good foundations for varieties improvement. [Method]The seeds and stem-segments were used as explants in the tissue culture of Pistacia vera 'Kerman',tissue culture condition and medium and transplant matrix were researched for micropropagation of pistachio,[Result]Mediums of 1/2DKW and 1/2DKW+3.00 mg/L of 6-BA +0.05 mg/L of NAA were suitable medium for seed germination and axillary bud induction of pistachio; Proliferation coefficient was 3.6 on the medium of 1/2DKW +4.00 mg/L of 6-BA + 0.05 mg/L of IBA; Rooting rate was up to 75% on the medium of 1/2DKW + 5.00 mg/L of IBA + 1.00 mg/L of NAA; The suitable transplantation matrix was 3/4 sand + 1/4 vermiculite,and survival rate of plant with root was above 79%. [Conclusion]The pistachio (Kerman) tissue culture technology system was established. 展开更多
关键词 Pistachio (Pistacia vera L.) Tissue culture TRANSPLANT
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Tissue Culture of Lespedeza cyrtobotrya 被引量:3
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作者 陈佳 李忠秋 陈晓阳 《Agricultural Science & Technology》 CAS 2011年第3期359-362,共4页
[Objective] The aim was to carry out study on tissue culture of Lespedeza cyrtobotrya. [Method] The seeds of L. cyrtobotrya were used as materials to study on its tissue culture. [Result] The best sterilization time t... [Objective] The aim was to carry out study on tissue culture of Lespedeza cyrtobotrya. [Method] The seeds of L. cyrtobotrya were used as materials to study on its tissue culture. [Result] The best sterilization time to L. cyrtobotrya seeds was 8 min with 2.1% NaClO,in which shooting percent reached 37.8% and no polluted situations occurred. In the primary culture with the MS as basal medium,the concentration of 6-BA showed a significant effect on the index of buds differentiation,the optimum differentiation culture medium was MS+BA 1.0 mg/L+NAA 0.1 mg/L+2,4-D 0.01 mg/L,on which the index of generation could reach 6.69. The optimum subculture medium was MS+6-BA 1.0 mg/L+2,4-D 0.05 mg/L. The plants can generate the highest roots and rooting percent with IBA 0.50 mg/L. [Conclusion] This study had provided theoretical basis for genetic improvement of L. cyrtobotrya. 展开更多
关键词 Lespedeza cyrtobotrya Tissue culture REGENERATION
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Optimization of Callus Induction Medium for Schisandga chinensis Baill via Uniform Design 被引量:7
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作者 张佳 金东淳 +1 位作者 金海林 刘权刚 《Agricultural Science & Technology》 CAS 2011年第1期141-143,共3页
[Objective]This study was to optimize callus induction medium for Schisandga chinensis Baill.[Method]Using callus induction rate as an indicator,uniform design was employed to optimize hormone combination at poly-fact... [Objective]This study was to optimize callus induction medium for Schisandga chinensis Baill.[Method]Using callus induction rate as an indicator,uniform design was employed to optimize hormone combination at poly-factors and poly-levels for callus induction from Schisandga chinensis Baill.[Results]Optimal hormone combinations depended on different explants:optimum medium for both tender leaf and petiole was MS +3 mg/L 6-BA,for stem segment was MS +3 mg/L 6-BA +0.6 mg/L NAA.[Conclusion]Uniform design is a time-saving and convenient method for the optimum medium for callus and yields a higher callus induction rate. 展开更多
关键词 Schisandga chinensis Baill Callus tissue Uniform design Callus induction rate
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Surface modification of Cu-25Cr alloy induced by high current pulsed electron beam 被引量:2
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作者 周志明 柴林江 +3 位作者 肖志佩 涂坚 王亚平 黄伟九 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2015年第6期1935-1943,共9页
A Cu-25Cr alloy prepared by vacuum induction melting method was treated by the high current pulsed electron beam (HCPEB) with pulse numbers ranging from 1 to 100. Surface morphologies and microstructures of the allo... A Cu-25Cr alloy prepared by vacuum induction melting method was treated by the high current pulsed electron beam (HCPEB) with pulse numbers ranging from 1 to 100. Surface morphologies and microstructures of the alloy before and after the treatment were investigated by scanning electron microscopy and X-ray diffraction. The results show that significant surface modification can be induced by HCPEB with the pulse number reaching 10. Craters with typical morphologies on the Cu-25Cr alloy surface are formed due to the dynamic thermal field induced by the HCPEB. Micro-cracks, as a unique feature, are well revealed in the irradiated Cu-25Cr specimens and attributed to quasi-static thermal stresses accumulated along the specimen surface. The amount of cracks is found to increase with the pulse number and a preference of these cracks to Cr phases rather than Cu phases is also noted. Another characteristic produced by the HCPEB is the fine Cr spheroids, which are determined to be due to occurrence of liquid phase separation in the Cu-25Cr alloy. In addition, an examination on surface roughness of all specimens reveals that more pulses will produce a roughened surface, as a result of compromising the above features. 展开更多
关键词 Cu-Cr alloy surface modification high current pulsed electron beam MICROSTRUCTURE
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Callus Induction and Cell Suspension Culture of Eggplant(Solanum melongena L.) 被引量:1
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作者 王凤华 李光远 +2 位作者 陈双臣 蒋燕 王少先 《Agricultural Science & Technology》 CAS 2013年第9期1220-1223,1243,共5页
[Objective] The aim of this article is to establish a cell suspension culture system for eggplant. [Method] Using orthogonal design, appropriate media were screened for callus induction, subculture and cell suspension... [Objective] The aim of this article is to establish a cell suspension culture system for eggplant. [Method] Using orthogonal design, appropriate media were screened for callus induction, subculture and cell suspension culture. [Result] The appropriate medium for callus induction was MS supplemented with 0.2 mg/L 6-BA and 0.2 mg/L NAA; the appropriate subculture medium was MS supplemented with0.2 mg/L 6-BA, 0.2 mg/L NAA, and 0.1 mg/L KT; the suitable medium for cell suspension culture was liquid MS medium supplemented with 0.4 mg/L NAA and 0.2mg/L. Cell growth curve was similar to "S" shape in the above suspension medium.The cell growth included four phases, the initial phase(1-3 d), the logarithmic phase(3-7 d), the steady phase(7-8 d), and the decline phase(8-11 d). With the increasing culture time, the number of suspension cells increased, and it reached the maximum value at the 7thd, about 3.8 ×105cells/ml. Then the number of cells began to decline rapidly. The cell vigor was the highest at the initial phase. Suspension cells grew best in the liquid MS medium supplemented with NAA(0.4 mg/L)and 6-BA(0.2 mg/L). The mitotic index reached the maximum, about 4.1% in the above medium, which suggested that this medium was suitable for cell suspension culture of eggplant. [Conclusion] Cell suspension culture system of eggplant provides a significant method for eggplant biotechnology. Genetic transformation and mutants screening can be carried out with this system. 展开更多
关键词 EGGPLANT CALLUS Suspension culture Growth curve
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Histological Study on Soybean Somatic Embryogenesis 被引量:10
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作者 赵桂兰 杨向东 +1 位作者 郭东全 胡赞民 《Agricultural Science & Technology》 CAS 2008年第2期49-53,75,共6页
Soybean somatic cell could induce the development of embryoid which was similar to embryo morphologically and structurally. Somatic embryogenesis system of soybean was used to conduct genetic transformation of soybean... Soybean somatic cell could induce the development of embryoid which was similar to embryo morphologically and structurally. Somatic embryogenesis system of soybean was used to conduct genetic transformation of soybean because of its several advantages such as higher transformational efficiency, beetter synchronism and fewer plant chimeras among transgenic plants. After infected with agrobacterium tumefaciens,the initiation, differentiation and development of young cotyledon embryogenic cell of soybean which was cultured on selective culture medium with kanamycin were investigated through histological study. The result showed that somatic embryo was differentiated in non-bud differentiation way. The embryogenic cells were differentiated from epidermis of explant or cells in 1 layer or 2 layers, with the division of embryogenic cells and degradation and disorganization of surrounding cells, the embryogenic cells would form embryoid with analogous suspensor structure. Later, globular embryoid would extrude from epidermis then developed into heart-shape embryo. The experiment was expected to provide theoretical reference for the construction of high transformational system of using plant somatic embryogenesis induced by young cotyledon of soybean. 展开更多
关键词 SOYBEAN Somatic embryogenesis HISTOLOGY
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Microstructure and defect of titanium alloy electron beam deep penetration welded joint 被引量:8
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作者 张秉刚 石铭霄 +1 位作者 陈国庆 冯吉才 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2012年第11期2633-2637,共5页
The microstructure, phase composition and cold shut defect of thick titanium alloy electron beam welded joint were studied. The results showed that the microstructure of weld zone was composed of α′ phase; the heat ... The microstructure, phase composition and cold shut defect of thick titanium alloy electron beam welded joint were studied. The results showed that the microstructure of weld zone was composed of α′ phase; the heat affected zone was divided into fine-grained zone and coarse-grained zone, the microstructure of fine-grained zone was primary α phase + β phase + equiaxed α phase, and the microstructure of coarse-grained zone was primary α phase + acicular α′ phase; the microstructure of base metal zone basically consisted of primary α phase, and a small amount of residual β phase sprinkled. The forming. reason of cold shut was analyzed, and the precaution of cold shut was proposed. 展开更多
关键词 TA15 titanium alloy electron beam welding MICROSTRUCTURE phase composition cold shut defect weld zone heataffected zone
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Effect of arc-ultrasound on microstructures and mechanical properties of plasma arc welded joints of SiC_p/Al MMCs 被引量:2
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作者 雷玉成 王志伟 陈希章 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2011年第2期272-277,共6页
The effect of arc-ultrasound on microstructures and mechanical properties of SiCp/6061A1 MMCs joints produced by arc-ultrasound plasma arc "in-situ" alloy-welding with different excitation frequencies was investigat... The effect of arc-ultrasound on microstructures and mechanical properties of SiCp/6061A1 MMCs joints produced by arc-ultrasound plasma arc "in-situ" alloy-welding with different excitation frequencies was investigated, in which argon-nitrogen mixture was used as plasma gas, Ti wire as filler and the arc-ultrasound was produced by modulating the plasma arc with high frequency. The results show that arc-ultrasound could refine the new reinforced composites such as TiC, TiN significantly, and improve their distribution greatly. And new phase A13Ti becomes finer and less. The test results of mechanical properties indicate that the maximum tensile strength of welded joints is gained when the excitation frequency is 50 kHz, and the maximum is 225 MPa, raising by about 7% comoared with conventional nlasma arc welding (PAW) (20q MPa). 展开更多
关键词 SiCp/A1 MMCs arc-ultrasound plasma arc welding microstructure and property
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浅谈金融行业女工工作技巧
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作者 唐瑞林 廖风华 张武平 《武汉金融》 北大核心 2002年第4期64-64,共1页
关键词 金融行业 女职工 工作技巧 思想政治工作 创新 子组织 合法权益
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Determination of Emodin and Chrysophanol Contents in Callus of Cassia tora L. Leaf 被引量:1
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作者 周嘉裕 廖海 +3 位作者 李利平 刘乐 贺葵邦 马丽 《Agricultural Science & Technology》 CAS 2008年第2期60-62,共3页
[ Objective] Through inductive culture, emodin and chrysophanol contents in cassia seed were increased. [ Method ] MS culture medium was used to bourgeon seedlings of cassia seed and to induce cotyledon callus of cass... [ Objective] Through inductive culture, emodin and chrysophanol contents in cassia seed were increased. [ Method ] MS culture medium was used to bourgeon seedlings of cassia seed and to induce cotyledon callus of cassia seed while HPLC method was adopted to determine emodin and ehrysophanol eontents.[ Result] Emedin and chrysophanol contents in cotyledon callus were 0. 099% and 0. 312%, respectively, while they were 0.029% and 0. 190% respectively in cassia seed. [ Conclusion] The method of inducing cotyledon callus was helpful for increasing emodin coment in cassia seed. 展开更多
关键词 Cassia seed CALLUS ANTHRAQUINONE HPLC
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Microstructure and mechanical properties of Ti-43Al-9V alloy fabricated by spark plasma sintering 被引量:2
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作者 徐丽娟 肖树龙 +1 位作者 陈玉勇 王娟 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2012年第4期768-772,共5页
A fine-grained TiAl alloy with the composition of Ti-43Al-9V was prepared by mechanical milling and spark plasma sintering(SPS).The relationship among sintering temperature,microstructure and mechanical properties w... A fine-grained TiAl alloy with the composition of Ti-43Al-9V was prepared by mechanical milling and spark plasma sintering(SPS).The relationship among sintering temperature,microstructure and mechanical properties was studied.The results show that the morphology of mechanical milling powder is regular with size in a range of 5-30 μm.Main phases of γ-TiAl,α2-Ti3Al and few B2 phase are observed in the SPS bulk samples.For samples sintered at 1150 °C,equiaxed crystal grain microstructure is achieved with size in a range of 300 nm-1 μm.With increasing SPS temperature to 1250 °C,the size of equiaxed crystal grains obviously increases,the microhardness decreases from HV592 to HV535,and the bending strength decreases from 605 to 219 MPa.Meantime,the compression fracture strength also decreases from 2601 to 1905 MPa,and the strain compression decreases from 28.95% to 12.09%. 展开更多
关键词 TiAl alloy mechanical alloying spark plasma sintering MICROSTRUCTURE mechanical properties
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