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红花化瘀汤治疗卒中后肩手综合征临床研究 被引量:2
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作者 徐日明 梁美珍 +1 位作者 杨文秀 林捷 《辽宁中医杂志》 CAS 2022年第11期109-111,共3页
目的 探讨红花化瘀汤治疗卒中后肩手综合征(SHS)的疗效。方法 选取该院收治的卒中后肩手综合征(SHS)患者108例,随机分为对照组(52例,常规康复训练)和试验组(56例,常规康复训练联合红花化瘀汤熏洗患肢),对比治疗后临床疗效、FMA评分、Bar... 目的 探讨红花化瘀汤治疗卒中后肩手综合征(SHS)的疗效。方法 选取该院收治的卒中后肩手综合征(SHS)患者108例,随机分为对照组(52例,常规康复训练)和试验组(56例,常规康复训练联合红花化瘀汤熏洗患肢),对比治疗后临床疗效、FMA评分、Barthel指数评分和疼痛视觉模拟(VAS)评分、SS-QOL评分和中医证候评分及血清降钙素基因相关肽(CGRP)和缓激肽(BK)水平。结果 试验组总有效率明显高于对照组(P<0.05);治疗后两组SS-QOL评分、ADL评分和FMA评分明显升高,VAS评分和中医证候评分明显降低(P<0.05);且试验组改善较明显(P<0.05);治疗后两组血清BK水平较治疗前明显降低,血清CGRP水平较治疗前明显升高(P<0.05);并且试验组改善较明显(P<0.05)。结论 采用红花化瘀汤治疗卒中后SHS具有较好的治疗效果,并且能够改善血清CGRP和BK水平。 展开更多
关键词 花化瘀汤 肩手综合征 临床疗效 CGRP和BK水平
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威海市区城市园林绿化花化整治探讨 被引量:1
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作者 许瑛 《绿色科技》 2019年第9期48-49,共2页
指出了威海市区开花乔灌木、彩叶树种的植物品种和栽植比例偏少,早春秋季冬季植物色彩不够丰富,景观缺少大色块,特别是在街道、房前、庭院等地缺少植被和花卉,不能产生强烈的视觉冲击,在一定程度上影响了城市的绿化景观。基于此,结合实... 指出了威海市区开花乔灌木、彩叶树种的植物品种和栽植比例偏少,早春秋季冬季植物色彩不够丰富,景观缺少大色块,特别是在街道、房前、庭院等地缺少植被和花卉,不能产生强烈的视觉冲击,在一定程度上影响了城市的绿化景观。基于此,结合实际,针对存在的问题提出了园林绿化花化整治工作建议,以期提供参考。 展开更多
关键词 威海 花化 整治 要点
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A coupled strain softening and hardening model for completely weathered granite in a fault zone
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作者 DU Shao-hua XIAO Peng +3 位作者 LI Di-yuan MAO Da-wei RUAN Bo ZHANG Rui-chao 《Journal of Central South University》 SCIE EI CAS CSCD 2024年第9期3225-3241,共17页
his study focused on exploring the specificity of mechanical behavior for completely weathered granite,as a special soil,by consolidated drained triaxial tests.The influences of dry density(1.60,1.70,1.80 and 1.90 g/c... his study focused on exploring the specificity of mechanical behavior for completely weathered granite,as a special soil,by consolidated drained triaxial tests.The influences of dry density(1.60,1.70,1.80 and 1.90 g/cm^(3)),confining pressure(100,200,400 and 600 kPa),and moisture content(13.0%,that is,natural moisture content)were investigated in the present work.A newly developed Duncan-Chang model was established based on the experimental data and Duncan-Chang model.The influence of each parameter on the type of the proposed model curve was also evaluated.The experimental results revealed that with varying dry density and confining pressure,the deviatoric stress–strain curves have diversified characteristics including strain-softening,strain-stabilization and strain-hardening.Under high confining pressure condition,specimens with different densities all showed strain-hardening characteristic.Whereas at the low confining pressure levels,specimens with higher densities gradually transform into softening characteristics.Except for individual compression shear failure,the deformation modes of the specimens all showed swelling deformation,and all the damaged specimens maintained good integrity.Through comparing the experiment results,the strain-softening or strain-hardening behavior of CWG specimens could be predicted following the proposed model with high accuracy.Additionally,the proposed model can accurately characterize the key mechanical indicators,such as tangent modulus,peak value and residual strength,which is simple to implement and depends on fewer parameters. 展开更多
关键词 completely weathered granite mechanical behavior consolidated drained triaxial test constitutive model
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山东棉花黄萎菌致病力分化的研究 被引量:26
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作者 吴献忠 李凤玲 +2 位作者 郑长英 王贻勇 朱有利 《植物保护》 CAS CSCD 北大核心 1995年第6期2-5,共4页
选用山东省有代表性的棉黄萎菌16个菌株(系)各配制成一定浓度的孢子悬浮液,于棉苗2~3叶期蘸根接种,观察发病的反应型。结果表明:各菌株致病力强弱差异明显,可分为致病力强的Ⅰ型(即与落叶型相似)、致病力中等的Ⅱ型和致病... 选用山东省有代表性的棉黄萎菌16个菌株(系)各配制成一定浓度的孢子悬浮液,于棉苗2~3叶期蘸根接种,观察发病的反应型。结果表明:各菌株致病力强弱差异明显,可分为致病力强的Ⅰ型(即与落叶型相似)、致病力中等的Ⅱ型和致病力弱的Ⅲ型,并发现山东省有落叶型菌系存在。 展开更多
关键词 棉花 花化萎缩病 黄萎菌 致病力 落叶型菌系
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Chemical constituents of the flower buds of Tussilago farfara 被引量:12
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作者 刘玉峰 杨秀伟 武滨 《Journal of Chinese Pharmaceutical Sciences》 CAS 2007年第4期288-293,共6页
Aim To study the chemical constituents of the flower buds of Tussilago farfara L. in the China National GAP Base of Traditional Chinese Materia Medica and provide scientific basis for quality control. Methods The cons... Aim To study the chemical constituents of the flower buds of Tussilago farfara L. in the China National GAP Base of Traditional Chinese Materia Medica and provide scientific basis for quality control. Methods The constituents were separated and purified by different chromatographic methods, and their structures were elucidated by IR, MS and NMR techniques. Results Twenty eight compounds were isolated from the flower buds of T. farfara. Their structures were identified as n- heptacosane (1), bis(2-ethylhexyl)phthalate (2), 7β-[3'-ethylcrotonoyloxy]-1α-[2'-methylbutyryloxy]-3,14-dehydro-Z-notonipetranone (3), 7β-[3'-ethylcrotonoyloxy]-1α-[2'-methylbutyryloxy]-3,14-dehydro-E-notonipetranone (4), tussilagone (5), dibutyl phthalate (6), bauer-7-ene-3β,16α-diol (7), isobauerenol (8), stigmasterol (9), β-sitosterol (10), 2,2-dimethyl-6-acetylchromanone (11), n- hexadecanoic acid (12), 7β-hydroxysitosterol (13), 7α-hydroxysitosterol (14), 7,14-bisdesacylnotonipetrone (15), 2,3- dihydroxypropylpalmitate (16), daucosterol (17), 6-hydroxy-2,6-dimethylhept-2-en-4-one (18), ferulic acid (19), isoferulic acid (20), caffeic acid (21), α-D-glucose (22), sucrose (23), phthalic acid (24), p-hydroxybenzoic acid (25), gallic acid (26), uridine (27), and adenosine (28). Conclusion Compounds 1, 12-16, 18 and 20 were obtained from the genus Tussilago for the first time. 展开更多
关键词 COMPOSITAE Flower buds of Tussilago farfara L. Chemical constituents
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BRASSICA DE-EXINED POLLEN AS A NEW EXPERIMENTAL SYSTEM FOR STUDYING POLLEN GERMINATION 被引量:1
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作者 徐秉芳 梁世平 +1 位作者 周嫦 杨弘远 《Acta Botanica Sinica》 CSCD 1997年第6期489-493,共5页
Exine deprived pollen only coated with inline has been isolated and artificially germinated in Brassica L. In view of the lack of exine and germ furrows, the de-exined pollen is an interesting experimental system for ... Exine deprived pollen only coated with inline has been isolated and artificially germinated in Brassica L. In view of the lack of exine and germ furrows, the de-exined pollen is an interesting experimental system for studying pollen germination. This report focuses on the microscopic and ultrastructural changes in the aspects of polarization, predetermination of the germination site and new wall synthesis during the course of isolation and germination of the de-exined pollen. It was shown that the de-exined pollen was already in an active state and had established its polarity and germination sites prior to exine detachment. The germination sites were still localized at the region of the previous germ furrows even after exine detachment. The new wall deposited at the germination sites appeared to have an important morphogenetic role in setting a limit to the size of pollen tube diameter . These results support our assumption that the de-exined pollen may have an extensive application in the research of pollen biology. 展开更多
关键词 De-exined pollen Pollen activation Pollen germination BRASSICA
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Research on Correlation between Synthesis of Stilbenes and Aflatoxin Accumulation Caused by Aspergillus flavus in Peanut Seeds 被引量:1
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作者 王琴飞 王明 +3 位作者 李莉萍 高玲 应东山 张如莲 《Agricultural Science & Technology》 CAS 2016年第2期265-272,278,共9页
In peanuts, a mechanism of resistance to fungal infection is reported on the synthesis of stilbene phytoalexins, which are antibiotic, low molecular weight metabolites. The phytoalexin-associated response of different... In peanuts, a mechanism of resistance to fungal infection is reported on the synthesis of stilbene phytoalexins, which are antibiotic, low molecular weight metabolites. The phytoalexin-associated response of different peanut varieties to the inoculation with A. flavus has not been investigated and might be useful for breed- ing resistant peanut cultivars. In this study, peanut varieties resistant or susceptible to aflatoxin accumulation caused by A. flavus were selected to compare the synthe- sis differences of the four main stilbenes (resveratrol, ε-viniferin, 6-viniferin and pterostilbene) and the activities of their resistant enzymes (PAL, POD, PPO), and explore the relationship between stilbene synthesis and resistance to aflatoxin accu- mulation. The results indicated that the synthesis speed of stilbenes was related to the resistance to aflatoxin accumulation in peanuts seeds. The total content of the four stilbenes reached the highest value of 47.37 μg/g in the resistant cultivars (Qian huasheng 3) after inoculation by A. flavus (54 times of the control) on the 3nd day, while the total content of stilbenes in susceptible cultivars (Huayu 22) was 5.5 μg/g. The content of stilbenes and the activities of their resistant enzymes from the resistant cultivars were both higher than from the susceptible one. The four peanut varieties with relative higher stilbene contents and lower disease index and aflatoxin content were selected by using the stilbene content. Very significant negative corre- lation, with correlation coefficients (r) of -0.789, -0.851 and -0.850, was observed between the stilbene content with disease index, the content of aflatoxin B1 and the total content of aflatoxins, respectively. Therefore, the study suggested that the total content of stilbene compounds might serve as an important chemical index in peanut seeds after inoculation with A. flavus on the 3nd day, during screening and breeding of peanut varieties resistant to aflatoxin accumulation. 展开更多
关键词 PEANUT STILBENES Aspergillus flavus Resistance
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CHANGES OF ENDOGENOUS HORMONE CONTENTS DURING FLORAL BUD AND VEGETATIVE BUD DIF FERENTIATION IN THIN CELL LAYER CULTURE OF CICHORIUM INTYBUS L. EXPLANT 被引量:10
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作者 李颖章 韩碧文 《Acta Botanica Sinica》 CSCD 1996年第2期131-135,共5页
The sectioned thin cell layers (TCL) of flower stalk of Cichorium intybus L. were cultured in MS medium supplemented with NAA and BA or IAA and BA where floral and vegetative buds were developed from the explant. ... The sectioned thin cell layers (TCL) of flower stalk of Cichorium intybus L. were cultured in MS medium supplemented with NAA and BA or IAA and BA where floral and vegetative buds were developed from the explant. Endogenous IAA, DHZ+DHZR, iPA increased significantly during the floral bud formation, while Z+ZR remained changed. The levels of cytokinins, DHZ+DHZR, iPA, and Z+ZR all increased significantly during the vegetative bud formation, however IAA level was reduced during the first 7 days of culture and increased to two thirds of initial values on the day when the bud primordia were formed. The results suggested that the initiation of floral buds was associated with a high IAA/CTK ratio, whereas the induction of vegetative bud differentiation was related to a low IAA/CTK ratio. 展开更多
关键词 Thin cell layer Cichorium intybus Floral buds formation Vegetative bud formation Phytohormone
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Crystallization microstructure of Mg_(65)Cu_(25)Y_(10) bulk amorphous alloy 被引量:3
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作者 黄康 陈刚 +2 位作者 赵玉涛 王国路 邵阳 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2012年第4期831-836,共6页
Mg65Cu25Y10 bulk amorphous alloy specimens prepared by conventional copper mould method were heated at 200 °C for different time and the phase contents as well as microstructure were studied.The XRD results show ... Mg65Cu25Y10 bulk amorphous alloy specimens prepared by conventional copper mould method were heated at 200 °C for different time and the phase contents as well as microstructure were studied.The XRD results show that the crystallization of Mg65Cu25Y10 bulk amorphous alloy specimen becomes complete as the treating time increases and Mg2Cu,Mg24Y5 and HCP-Mg crystalline phases are found.Snowflake-like morphology is found in different specimens through SEM observation.The EDS patterns show that the composition of the snowflake-like structure is close to that of the as-cast alloy.Laminated structures are observed from the TEM images of the snowflake-like structure.From the electron diffraction patterns,it is seen that the snowflake-like structure is the combination of Mg24Y5 and amorphous matrix.The FCC-Mg phase in the matrix transforms into HCP-Mg during the heat-treating process. 展开更多
关键词 Mg-based bulk amorphous alloy CRYSTALLIZATION snowflake-like structure laminated structure
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TiB_2/Ni coatings on surface of copper alloy electrode prepared by electrospark deposition 被引量:13
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作者 罗成 熊翔 董仕节 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2011年第2期317-321,共5页
In order to improve the lifespan of spot-welding electrodes used for welding zinc coated steel sheets, titanium diboride was deposited onto their surface after precoating nickel as an intermediate layer. The microstru... In order to improve the lifespan of spot-welding electrodes used for welding zinc coated steel sheets, titanium diboride was deposited onto their surface after precoating nickel as an intermediate layer. The microstructures and phase compositions of TiB2 and Ni coatings were characterized by SEM and XRD. The coating hardness was measured using a microhardness tester. The results indicate that a satisfactory TiB2 coating is obtained as a result of the intermediate nickel layer acting as a good binder between the TiB2 coating and the copper alloy substrate. Owing to its capacity of deforming, the precoated nickel layer is dense and crack free, while cracks and pores are observed in the TiB2 coating. The hardness of the TiB2/Ni coating decreases with the increase of voltage and capacitance because of the diffusion of copper and nickel and the oxidation of the coating materials. Because of the good thermal and electrical conductivities and high hardness properties of TiB2, the deformation of the electrode with TiB2/Ni coating is reduced and its spot-welding life is by far prolonged than that of the uncoated one. 展开更多
关键词 titanium diboride electrospark deposition COPPER ELECTRODE NICKEL COATING
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Physiological Mechanism for Anthocyanins to Strengthen the Drought Tolerance of Plants 被引量:4
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作者 唐小华 赵昶灵 +4 位作者 文国松 王文亚 王崇德 孙艳 白雪嵩 《Agricultural Science & Technology》 CAS 2014年第11期1935-1941,共7页
This paper summarized the possible physiological mechanism by which anthocyanins strengthen the tolerance of plants to drought. Drought stress can in-duce plant cel s to synthesize and accumulate anthocyanins. The pho... This paper summarized the possible physiological mechanism by which anthocyanins strengthen the tolerance of plants to drought. Drought stress can in-duce plant cel s to synthesize and accumulate anthocyanins. The photochemical properties, subcel ular accumulation sites and spatial distributions in plant organs and tissues of anthocyanins determine their function of strengthening plant tolerance, which is realized by three possible physiological mechanisms: (1) anthocyanins and their chelated metal ions can optimize the osmoregulation ability of the plant cel s by directly acting as the osmoregulation substances of the cel s, (2) anthocyanins with suitable spatial locations can reduce the photoinhibition of the plants under drought stresses, (3) anthocyanins can effectively maintain and improve the active oxygen-scavenging capacity of the plant cel s under drought conditions. Therein, that the anthocyanins enhance the antioxidant capacity of the plant cel s under drought stresses is probably the main reason for the anthocyanins to strengthen the drought tolerance of plants. This review could provide a reference for the mechanism re-search of the drought resistance and the breeding of the drought-resistant cultivars for the plants holding the ability to synthesize and accumulate anthocyanins. 展开更多
关键词 Anthocyanins Strengthen Plant drought tolerance Physiological mech-anism
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Extraction Characteristics of Anthocyanins from Preliminarily-processed Products of Purple Sweet Potatoes during the Gelatinization Process 被引量:1
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作者 魏传斌 张萍 《Agricultural Science & Technology》 CAS 2015年第5期1084-1087,共4页
Objective] This study aimed to investigate the method for efficient utilization and development of purple sweet potatoes. [Method] Purple sweet potatoes were dried at two specific temperatures and prepared into prelim... Objective] This study aimed to investigate the method for efficient utilization and development of purple sweet potatoes. [Method] Purple sweet potatoes were dried at two specific temperatures and prepared into preliminarily-processed products for gelatinization simulation to analyze the extraction amount of anthocyanins from gelatinized samples at different gelatinization stages. [Result] During the gelatinization process, the extraction rate of anthocyanins from purple sweet potato samples reached the highest as the temperature rised from 90 ℃ to 95 ℃,and the extraction amount of anthocyanins reached the maximum at 15 min postheat preservation at 95 ℃. Purple sweet potato samples dried at 60 ℃ exhibited larger retention amount, larger maximum extraction amount and higher maximum extraction rate of anthocyanins compared with those dried at 110 ℃. [Conclusion] Drying at low temperatures and appropriately shortening the initial gelatinization stage below 90 ℃ is conducive to the retention and extraction of anthocyanins from purple sweet potatoes. 展开更多
关键词 Purple sweet potatoes ANTHOCYANIN Starch gelatinization EXTRACTION
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Plant Developmental Biology in China: Past, Present and Future 被引量:5
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作者 许智宏 种康 《Acta Botanica Sinica》 CSCD 2002年第9期1085-1095,共11页
Plant development is a process from germination of seed to vegetative growth, flower initiation and development, fertilization and finally to the next generation seed formation. A lot of achievements have been obtai... Plant development is a process from germination of seed to vegetative growth, flower initiation and development, fertilization and finally to the next generation seed formation. A lot of achievements have been obtained in plant developmental biology in China. Since the 1990's, those young generation scientists returned to China from abroad to use molecular and genetic techniques to study morphological, physiological and biochemical process of plant development. The present paper reviews the progress in some research area of plant developmental biology in the past decades and also prospects the chance and future of plant developmental studies, due to the recent advances of plant genome sequencing and functional genomics in China under the international research background. 展开更多
关键词 developmental biology organ differentiation flowering physiology sexual differentiation fertilization biology seed physiology
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桃树的夏季管理 被引量:5
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作者 谢艳 孙书品 《四川农业科技》 2005年第5期21-21,共1页
关键词 桃树 夏季管理 修剪 花化控技术 病虫害防治
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Esterification of cyclohexene with formic acid over a peanut shell-derived carbon solid acid catalyst 被引量:17
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作者 薛伟 赵贺潘 +2 位作者 姚洁 李芳 王延吉 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2016年第5期769-777,共9页
A carbon solid acid catalyst was prepared by the sulfonation of partially carbonized peanut shell with concentrated H2SO4. The structure and acidity of the catalyst were characterized by Fourier transform infrared spe... A carbon solid acid catalyst was prepared by the sulfonation of partially carbonized peanut shell with concentrated H2SO4. The structure and acidity of the catalyst were characterized by Fourier transform infrared spectroscopy, scanning electron microscopy, X‐ray diffraction, thermogravimetric analysis, X‐ray photoelectron spectroscopy, and elemental analysis, which showed that it was an amorphous carbon material composed of aromatic carbon sheets in random orientations. Sulfonic acid groups were present on the surface at a density of 0.81 mmol/g. The carbon solid acid catalyst showed better performance than HZSM‐5 for the esterification of cyclohexene with formic acid. At a3:1 molar ratio of formic acid to cyclohexene, catalyst loading of 0.07 g/mL of cyclohexene, and reaction time of 1 h at 413 K, the cyclohexene conversion was 88.4% with 97.3% selectivity to cyclohexyl formate. The carbon solid acid catalyst showed better reusability than HZSM‐5 because its large pores were minimally affected by the accumulation of oligomerized cyclohexene, which deactivated HZSM‐5. The activity of the carbon solid acid catalyst decreased somewhat in the first two recycles due to the leaching of polycyclic aromatic hydrocarbon containing –SO3H groups and then it remained constant in the following reuse. 展开更多
关键词 Carbon solid acid Peanut shell CYCLOHEXENE ESTERIFICATION Cyclohexyl formate
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Establishment of Green Cotton Regeneration System 被引量:3
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作者 侍福梅 王超 《Agricultural Science & Technology》 CAS 2010年第1期8-11,共4页
[Objective]The aimed to optimize transformation system for Agrobacterium-mediated green cotton shoot tip and provide reference for genetic engineering-assisted breeding of color cotton. [Method]With shoot tip of natur... [Objective]The aimed to optimize transformation system for Agrobacterium-mediated green cotton shoot tip and provide reference for genetic engineering-assisted breeding of color cotton. [Method]With shoot tip of natural green cotton as receptor and by using Agrobacterium-mediated transformation method,the optimum conditions of regeneration system were obtained. [Result]Combining with vacuum infiltration,3-old-day shoot tips were infected for 10 minutes in Abarobacterium suspension with OD600 value about 0.5 followed by co-culture for 24 h on the medium containing MS+l mg/L KT,pH value of 5.8. The regeneration culture was conducted in MS medium containing l mg/L KT and increasingly 30,50 and 70 mg/L Kan. The highest transformation frequency was 34.6%,and the positive resistant plantlets of green cotton 9804 were obtained. [Conclusion]Green cotton is more beneficial than white cotton to conduct genetic transformation. 展开更多
关键词 Green cotton Shoot tip Genetic transformation AGROBACTERIUM
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“耗费”义动词“花”与“化”的关系问题探析 被引量:1
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作者 吕军伟 《大连大学学报》 2011年第2期74-77,共4页
耗费义"花动"始见于宋元时期,而非清代。在耗费义"花动"类合成动词中,"花费"最先词汇化,始见于元代。"耗费"义动词"化(hua)"始见于明代的"化费",其在出现时间和用例数量上... 耗费义"花动"始见于宋元时期,而非清代。在耗费义"花动"类合成动词中,"花费"最先词汇化,始见于元代。"耗费"义动词"化(hua)"始见于明代的"化费",其在出现时间和用例数量上,都远远滞后于耗费义"花动"。而作为"耗费"义动词‘花'与‘化(hua)'之关系有待深入考证。 展开更多
关键词 “耗费”义 “花动” “化”(hua hua) 关系
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Sex Expression and the Evolutionary Advantages of Male Flowers in an Andromonoecious Species, Sagittaria guyanensis subsp. lappula (Alismataceae) 被引量:4
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作者 黄双全 宋旎 +2 位作者 汪泉 唐璐璐 汪小凡 《Acta Botanica Sinica》 CSCD 2000年第11期1108-1114,共7页
Sex expression in Sagittaria guyanensis H.B.K. subsp. lappula (D. Don) Bojin is typically andromonoecious while the other species in the same genus are basically monoecious. The evolutionary advantages of male... Sex expression in Sagittaria guyanensis H.B.K. subsp. lappula (D. Don) Bojin is typically andromonoecious while the other species in the same genus are basically monoecious. The evolutionary advantages of male flowers and hermaphrodite flowers in S. guyanensis subsp. lappula were assessed by measuring sex allocation and pollen movements in two wild populations of the species. Two cultivated populations served as controls. The percentage of male flowers was very low in the two wild populations in Dongxiang, Jiangxi Province and Wuyishan, Fujian Province, viz., 2.48% and 0.96% respectively. In the two cultivated populations, male flower percentage significantly increased when the soil was of higher nutrient content. This indicates that the allocation to male versus female reproduction might change in response to environmental factors. Pollen production per male flower was 4.1 times higher than that of a hermaphrodite flower. The floral shape and size of male and hermaphrodite flowers were similar. No difference was observed between these dimorphological flowers in pollen germination rate in vitro and in the speed of pollen tube growth in vivo . Anthesis was only 4-5 h. Male flowers usually opened 0.5 h earlier than hermaphrodite flowers. An unexpected finding was that no pollen from the male flowers was found on the stigmas of the hermaphrodite flowers, in spite of the occasional visits by insects to both types of flowers in both wild and control populations. A consistent pattern of fruit development was found to exist in open pollinated flowers as well as in flowers that had been bagged. The sex ratios did not have significant influence on fruit set. Approximately 25% of the pistils in a gynoecium failed to develop into fruits because no pollen was deposited on them, indicating that the fruit set of this andromonoecious plant is mainly affected by pollen limitation rather than resource limitation. Reproduction in S. guyanensis subsp. lappula in the habitats was dependent on self_pollination in hermaphrodite flowers. The male flowers in this species might be a potential source of additional pollination and may facilitate cross_pollination. The fact that the flowers of monoecious species in Sagittaria pollinated by a wide diversity of insect visitors may contribute enormously to the diversification of sex expression in this genus. 展开更多
关键词 Sagittaria guyanensis subsp. lappula sex expression ANDROMONOECY evolutionD
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The New Discoveries of Specific Characteristics of Yulania Spach 被引量:2
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作者 赵东欣 赵东武 孙军 《Agricultural Science & Technology》 CAS 2008年第1期54-59,共6页
The research history and new discoveries of the specific characteristics of Yulania Spach were reported, as to the specific characteristics, such as the terminal , axillary and fascicled similar flower buds,sometimes ... The research history and new discoveries of the specific characteristics of Yulania Spach were reported, as to the specific characteristics, such as the terminal , axillary and fascicled similar flower buds,sometimes polycymes; 2-4 flower types of a plant; two spathe-like stipoles of single flower; drape or overlap of tepals, deep split or shallow split on the edge of tepals. The discoveries could provide valuable information for the further studies on the taxonomic system, anthotaxical evolution, phylogenetic relationship and breeding. 展开更多
关键词 Yulania Spach Specific characteristics New discoveries
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Antioxidase Activities of Tetraploid Lines and Diploid Control Line of Chrysanthemum cinerariifolium 被引量:5
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作者 刘蓁 高山林 《Agricultural Science & Technology》 CAS 2009年第6期84-86,共3页
Objective The SOD, POD and APX enzyme activities of tetraploid lines and diploid control line of Chrysanthemum cinerariifolium in test-tube and field were determined in order to provide a reference for the selective b... Objective The SOD, POD and APX enzyme activities of tetraploid lines and diploid control line of Chrysanthemum cinerariifolium in test-tube and field were determined in order to provide a reference for the selective breeding of high resistance good tetraploid varieties of C. cinerariifolium. Method The SOD, POD and APX activities of each sample were determined. Every material should have 3 replicates which been determined and calculated mean value to analyze. Result The various kinds of antioxidase activities in protective enzyme system of tetraploid lines were increased generally in comparison with that of diploid control line. And there is certain relativity between the samples in field and in test-tube of these lines. Conclusion The antioxidase activities of each line in test-tube could be considered as reference index to screen high resistance good tetraploid varieties of C. cinerariifolium. 展开更多
关键词 Chrysanthemum cinerariifolium (Trev.) Vis. Antioxidase activities Selective breeding of good varieties
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