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1.
叶面施硒对大蒜生理特性、含硒量和产量的影响   总被引:2,自引:0,他引:2  
采用不同浓度的亚硒酸钠进行大蒜叶面喷施的田间试验。结果表明:硒浓度500mg/kg时,其超氧化物歧化酶活性最强,且一定的硒浓度可提高大蒜过氧化氢酶的活性;施硒大蒜中全硒、有机硒和无机硒含量提高,且有机硒的转化率与硒浓度增加成正比;全硒、有机硒和无机硒含量在硒浓度10000mg/k时迭最高;≤10mg/kg的低浓度硒有利于大蒜产量的增加;综合各因素,大蒜叶面积施硒以不超过10mg/kg为宜。  相似文献   

2.
采用土培与水培相结合方式,以油菜为样本,用亚硒酸钠以质量浓度为9、12、15、18、21、24mg/L的硒对照7个处理补硒,研究了硒对油菜苗期根系生长及还原力的影响,结果显示:不同质量浓度硒处理都比对照能保持根系的生长活力,在补硒质量浓度小于9mg/L处理时,能提高根冠比;补硒质量浓度小于15mg/L范围内,随补硒的质量浓度增加,根系的生物量亦增加;在补硒质量浓度小于21mg/L时,根系的还原活力随硒的质量浓度上升而增加;而高质量浓度的硒处理根系的还原活力降低、根冠比下降、根系的生物量减少.  相似文献   

3.
硒的生物学效应及与银屑病的关系   总被引:2,自引:0,他引:2  
介绍了有关硒的生物学效应、硒及GSH-px与银屑病发病治疗的关系,指出皮肤对硒的吸收或利用存在一定的屏障作用,即“血-皮肤屏障”,外用补硒疗法可能是克服这一屏障、提高银屑病治疗效果的有效疗法。  相似文献   

4.
关于提高茶叶含硒量途径的探讨   总被引:6,自引:0,他引:6  
系统分析了各种因素对茶叶含硒量的影响,研究结果表明:茶树品种,采摘季节、立土条件。特别是土壤中有效硒含量,均对茶叶含硒量有明显影响,3种因素的交互作用可使茶叶含硒量相差百倍以上,而制茶工艺对商品茶含一没有明显影响,认为通过品种选育、采摘季节的调节、提高土壤有效硒含量、寻找富硒土壤建立高硒茶基地是提高茶叶含一和保健人垢可能途径。  相似文献   

5.
为了探究硫酸盐对粘红酵母X-20(Rhodotorula glutinis X-20)富硒的影响,在恒定浓度亚硒酸钠和梯度浓度硫酸钠条件下培养R.glutinis X-20,研究硫酸盐对R.glutinis X-20生物量、总硒及硒纳米颗粒的影响,并使用RT-qPCR初步探索了硫酸盐调节R.glutinis X-20富硒的分子机制。研究发现,硫酸钠的添加使菌株的生物量提高了48.5%,总硒及硒纳米颗粒含量分别降低了36.7%和48.8%。RT-qPCR分析显示硫酸盐会抑制硒代谢关键基因CTH、metE、metB的表达,造成硫酸盐存在条件下总硒及硒纳米颗粒含量下降。硫酸盐的添加提高了R.glutinis X-20在亚硒酸钠环境中的生物量,这对富硒酵母产品的大规模生产具有重要意义。同时,RT-qPCR的结果也为R.glutinis X-20在分子生物学上的优化指明了方向。  相似文献   

6.
外源硒对胡萝卜生理生化特性、富硒性及其产量的影响   总被引:3,自引:0,他引:3  
采用不同浓度亚硒酸钠(NasSeO3)进行胡萝卜叶面喷施田间试验,研究硒对胡萝卜硒富集、产量及其生理生化特性的影响.结果表明:叶面施硒可明显提高胡萝卜中各形态硒含量,随施硒量的增加,有机硒转化率随之上升;其全硒、有机硒含量在最大处理浓度(500mg/kg)最高,分别是CK的15.9和26.6倍.施硒除在个别硒浓度提高SOD和CAT活性外,其余浓度酶活降低;施硒低于10mg/kg时有利于胡萝卜叶绿素合成;硒对胡萝卜光和速率则表现负效应.施硒胡萝卜产量较对照降低未达显著水平.综合分析硒对胡萝卜含硒量、产量及其生理生化、以及对人、畜食用的安全性,施硒量以不超过1.0mg/kg为宜.  相似文献   

7.
微量元素硒与肿瘤的关系   总被引:11,自引:0,他引:11  
近几年国内外基础医学研究表明微量无量硒对肿瘤有预防和治疗作用,补硒能使其发病率和死亡率降低。本文重点综述硒与肿瘤发生发展的关系,总结了硒防癌抗癌机制,硒与消化道肿瘤、乳腺癌、前列腺癌的相关性.  相似文献   

8.
以硒化葡糖24%的剂量给荷艾氏腹水瘤的小鼠灌胃后,该组小鼠的平均存活天数比给相应剂量的非硒化葡聚糖组显增加,生命延长率为31.1%。将含有微量元素硒的茶多酚与不含硒的茶多酚比较,结果显示含硒茶多酚与不含硒的茶多酚比较,结果显示含硒多酚的抑制瘤作用更明显。  相似文献   

9.
 纳米硒作为一种新型单质硒,与有机硒和无机硒相比具有更高的生物利用度,更强的生物活性和更低的毒性,并且具有抗氧化和抗肿瘤的作用。概述了纳米硒在生物医药中的应用,包括纳米硒用于化疗、放疗、放化疗以及其他临床药物的增敏,纳米硒的功能化和靶向修饰增强抗肿瘤效果,含硒纳米材料在抗肿瘤中的应用,纳米硒的毒理学,介绍了纳米硒制剂产业化发展情况。  相似文献   

10.
硒对蛹虫草生长发育的影响   总被引:3,自引:0,他引:3  
以蛹虫草作为富集硒的载体,用不同浓度的含硒培养基分别对蛹虫草的子实体进行培养,以研究蛹虫草的耐硒能力.结果表明:采用固体培养基培养蛹虫草子实体,在含硒0.5—20mg/kg的固体培养基上,菌丝均能生长;在含硒0.5—5.0mg/kg范围内,子实体生长速度较其他浓度明显提高;在含硒10.0—20.0mg/kg范围内,子实体生长受到抑制;在含硒30mg/kg以上的培养基上,菌丝不能生长。  相似文献   

11.
Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.  相似文献   

12.
何延凌 《科技信息》2008,(4):258-258
Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women's language from these perspectives: pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women's language, more attention should be paid to language use in social context. What's more, the linguistic phenomena in a speaking community can be understood more thoroughly.  相似文献   

13.
理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。  相似文献   

14.
As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.  相似文献   

15.
正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula-  相似文献   

16.
We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re-  相似文献   

17.
正The electronic and nuclear(structural/vibrational)response of 1D-3D nanoscale systems to electric fields gives rise to a host of optical,mechanical,spectral,etc.properties that are of high theoretical and applied interest.Due to the computational difficulty of treating such large systems it is convenient to model them as infinite and periodic(at least,in first approximation).The fundamental theoretical/computational problem in doing so is that  相似文献   

18.
For molecular systems,the quantum-mechanical treatment of their responses to static electromagnetic fields usually employs a scalar-potential treatment of the electric field and a vector-potential treatment of the magnetic field.Although the potential for each field separately is associated with the choice of an(unphysical)origin,the precise choice of the origin for the electrostatic field has little consequences for the results.This is different for the  相似文献   

19.
Franck-Condon factors bridge the gap between theoretical modeling and experimental observations for molecular electronic spectroscopy and electron transfer.Under the displaced harmonic oscillator approximation,multidimensional Franck-Condon factors are decomposed into a product of many one-dimensional(1D)Franck-Condon(FC)factors,and each 1D-FC factor is associated with one Huang-Rhys factor that determines the leading contribution of  相似文献   

20.
<正>"The Journal of Shanghai Normal University:Mathematics"is published by Shanghai Normal University as regular issues of The Journal of Shanghai Normal University each year from 2014 in English.The editors-in-chief of the issues are professors Yuhao Cong and Maoan Han.The Journal of Shanghai Normal University was started in 1958 with  相似文献   

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