平卧菊三七茎段组织培养快速繁殖

在平卧菊三七自然繁殖率偏低的情况下,探讨利用组织培养方法解决繁殖问题。主要利用诱导丛生不定芽培养基培育形成试管苗,移栽成活,能进行大田栽培;同时还试验了3种培养基对茎段带菌液体培养生根生长的影响,研究结果：3种自来水带菌液体培养基对平卧菊三七带顶芽茎段培养长出须根系的条数为：配方3〉配方1〉配方2,诱导培养长出须根的长...     

我国贝母组织培养研究概况

本文对我国贝母属植物的组织培养研究现状作了分析和归纳，总结了贝母组织培养在以下方面的研究成果：１、愈伤组织的诱导；贝母碱生产；３、胚状体诱导；４、器官分化；５、分化过程中的生理生化变化。     

文山三七块根的植物组织培养研究

选择云南文山三七块根为外植体,采用全面实验法或正交实验法,研究组织培养过程中外植体最佳表面消毒方案和最佳愈伤组织诱导、分化生芽、生根方案.试验结果表明,三七块根最佳表面灭菌方案为75%乙醇消毒10 s,再用2%次氯酸钠溶液消毒15 min;最佳愈伤组织诱导培养基为MS+蔗糖30 g/L+琼脂8 g/L+KT1.0mg/L+2,4-D1.0mg/L,批pH=5.8;生芽生根培养基可以选择MS+蔗糖30 g/L+琼脂8 g/L+2,4-D0.5 mg/L+NAA1.0mg/L NAA+6-BA1.0mg/L,pH=5.8.     

金线莲组织培养研究进展

从外植体选择、消毒方法、愈伤组织诱导与种子萌发、不定芽、芽与原球茎诱导、继代与增殖培养、壮苗生根、炼苗移栽、组培苗与野生苗比较、多倍体诱导、人工种子等方面对金线莲组织培养的研究进展进行梳理,以期对金线莲组织培养研究提供参考。     

三七叶甙对兔血小板聚集功能的影响

 应用Born氏比浊法分别测定三七叶甙(Panax notoginseng folium saponins)对花生四烯酸(arachidonic acid,AA)、血小板活化因子(platelet activating factor,PAF)和腺苷二磷酸(adenosine diphosphate,ADP)诱导的兔血小板聚集功能的影响.实验结果表明:三七叶甙在体外显著抑制ADP诱导的血小板聚集,其半数抑制浓度(medium inhibitory concentration,IC₅₀)为89.4mg/L;三七叶甙静脉注射也能明显降低ADP诱导的兔血小板聚集率,且呈剂量-效应关系.提示三七叶甙体内外均明显抑制ADP诱导的兔血小板聚集,而对AA和PAF诱导的兔血小板聚集无明显影响.     

菊花愈伤组织的诱导及器官再生

利用植物组织培养技术已大量繁殖出各种花卉。菊花茎、叶片、花托的组织培养已有报道,而以叶柄作为外植体的组织培养尚未见报道。本文阐述观察生长素NAA、2,4-D与细胞分裂素BA的不同浓度组合对菊花叶柄、茎段愈伤组织诱导及植株再生的影响,以及再生苗与实生苗的叶柄外植体愈伤组织的诱导和芽分化的比较。     

蔗糖浓度和外源2,4-D与KT浓度对三七幼叶细胞悬浮培养影响的研究

将云南文山三七幼叶诱导出愈伤组织,并采用悬浮震荡培养三七细胞.细胞培养基质中的碳源浓度和激素浓度对培养细胞生长的影响进行研究,实验结果显示:MS+1.5 mg/L2,4-D+1.0 mg/L KT+28 g/L蔗糖,pH为5.8的培养基最适合文山三七幼叶诱导得到的愈伤组织细胞悬浮的培养.     

贝母组织培养研究进展

在查阅国内外相关文献的基础上,从培养条件、小鳞茎再生、种质低温保存、生物碱积累、多倍体诱导等方面概述了贝母组织培养取得的研究成果,并提出了贝母组织培养中今后亟需解决的问题。     

马铃薯微型薯诱导简报

马铃薯试管微型薯是通过组织培养在容器内诱导试管苗于叶腋内形成的小薯[1].试管微型薯诱导技术自70年代中期首次报道以来,现在已被广泛应用于种质资源保存、交换、无毒种薯生产及马铃薯基因工程研究与应用中,本试验研究了克新4号和东农303,在二种培养方式、二种碳源、二种调节剂条件下诱导结薯情况.     

多肉植物黑王子组织培养体系的研究

为快速繁殖多肉植物黑王子(Echeveria‘Black Prince’),建立其组织培养体系,试验采用黑王子叶片为外植体进行离体培养研究.结果表明:黑王子不经过愈伤组织的诱导阶段,即能从外植体上直接诱导分化出不定芽,其最适培养基为MS+1.0mg/L 6-BA+0.5mg/L NAA,诱导率高达94.6%;最适的不定芽生根培养基为MS+0.5mg/L NAA,生根率达92.0%;试管苗的移栽成活率为95.0%.本研究建立了黑王子快速、高效繁殖的组织培养体系,为其工厂化生产与利用提供了技术保障.     

Markedness and its Interpretation in Language Use

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.     

Characterization of Ordovician carbonate reservoirs, southeastern Saskatchewan, Canada

The discovery of the prolific Ordovician Red River reservoirs in 1995 in southeastern Saskatchewan was the catalyst for extensive exploration activity which resulted in the discovery of more than 15 new Red River pools. The best yields of Red River production to date have been from dolomite reservoirs. Understanding the processes of dolomitization is, therefore, crucial for the prediction of the connectivity, spatial distribution and heterogeneity of dolomite reservoirs.The Red River reservoirs in the Midale area consist of 3～4 thin dolomitized zones, with a total thickness of about 20 m, which occur at the top of the Yeoman Formation. Two types of replacement dolomite were recognized in the Red River reservoir: dolomitized burrow infills and dolomitized host matrix. The spatial distribution of dolomite suggests that burrowing organisms played an important role in facilitating the fluid flow in the backfilled sediments. This resulted in penecontemporaneous dolomitization of burrow infills by normal seawater. The dolomite in the host matrix is interpreted as having occurred at shallow burial by evaporitic seawater during precipitation of Lake Almar anhydrite that immediately overlies the Yeoman Formation. However, the low δ18O values of dolomited burrow infills (-5.9‰～ -7.8‰, PDB) and matrix dolomites (-6.6‰～ -8.1‰, avg. -7.4‰ PDB) compared to the estimated values for the late Ordovician marine dolomite could be attributed to modification and alteration of dolomite at higher temperatures during deeper burial, which could also be responsible for its 87Sr/86Sr ratios (0.7084～0.7088) that are higher than suggested for the late Ordovician seawaters (0.7078～0.7080). The trace amounts of saddle dolomite cement in the Red River carbonates are probably related to "cannibalization" of earlier replacement dolomite during the chemical compaction.     

低渗透非均质砂岩油藏启动压力梯度研究

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。     

On Tragic Consciousness In The Works By Ernest Hemingway

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.     

A computer generator for randomly layered structures

AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…     

An Index mechanism for multi-scale view in spatial databases

There are numerous geometric objects stored in the spatial databases. An importance function in a spatial database is that users can browse the geometric objects as a map efficiently. Thus the spatial database should display the geometric objects users concern about swiftly onto the display window. This process includes two operations:retrieve data from database and then draw them onto screen. Accordingly, to improve the efficiency, we should try to reduce time of both retrieving object and displaying them. The former can be achieved with the aid of spatial index such as R-tree, the latter require to simplify the objects. Simplification means that objects are shown with sufficient but not with unnecessary detail which depend on the scale of browse. So the major problem is how to retrieve data at different detail level efficiently. This paper introduces the implementation of a multi-scale index in the spatial database SISP (Spatial Information Shared Platform) which is generalized from R-tree. The difference between the generalization and the R-tree lies on two facets: One is that every node and geometric object in the generalization is assigned with a importance value which denote the importance of them, and every vertex in the objects are assigned with a importance value,too. The importance value can be use to decide which data should be retrieve from disk in a query. The other difference is that geometric objects in the generalization are divided into one or more sub-blocks, and vertexes are total ordered by their importance value. With the help of the generalized R-tree, one can easily retrieve data at different detail levels.Some experiments are performed on real-life data to evaluate the performance of solutions that separately use normal spatial index and multi-scale spatial index. The results show that the solution using multi-scale index in SISP is satisfying.     

Achieving Unusual States of Matter Under High Pressure

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-     

Exchange-Correlation and Electronic Excitation Energies from Pairing Matrix Fluctuations

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-     

Density Functional Theory for the Response of Periodic Systems to Electric Fields Based on the Vector Potential Approach

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     

On the Thermodynamic Limit for Responses to Static Electromagnetic Fields

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