雨生红球藻原生质体制备与再生育种

研究了高渗溶液组成及浓度、酶的组成与质量分数、预处理方法、温度和pH等因素对雨生红球藻原生质体制备与再生的影响.结果表明:选用细胞数约为106·mL-1的对数生长期细胞,于50 mmol·L-1EDTA和25 mmol·L-1 DTT缓冲液,30℃下恒温处理1h,再于质量分数2.0%蜗牛酶和质量分数1.0%纤维素酶,温...     

木质素降解菌L1原生质体的形成和再生

从自然界筛选出一株降解木质素高的白腐真菌 L1,对其原生质体的形成和再生进行了研究。在 OS培养基中生长的菌丝体 ,原生质体数量较高。在液体培养条件下 ,于 OS培养基中培养 60 h的菌丝体 ,用 0 .3% β-巯基乙醇与酶液同时处理菌丝体 ,采用 p H5 .0的混合酶 (蜗牛酶∶纤维素酶∶溶菌酶的最佳浓度比为 5∶ 4∶ 1 ) ;在 30℃酶解 4h;用 0 .4mol/L NH4Cl,1 0 mmol/L Mg SO4作渗透压稳定剂时 ,原生质体数量达到 4.32× 1 0 5个 /mg。 OS双层再生培养基最适于原生质体再生     

槐耳原生质体制备与再生研究

对槐耳原生质体制备与再生进行了研究,结果表明:槐耳原生质体制备最佳条件是以液体静置培养9d的菌丝体,0.6mol/L蔗糖作为渗透压稳定剂,在体积质量比2%溶壁酶、1%纤维素酶和1%蜗牛酶作用下,25℃酶解3h,制备率达2.75×106个/mL;再生最佳条件是液体静置培养12d的菌丝体,0.6mol/L甘露醇为渗透压稳定剂,在2%溶壁酶作用下,35℃酶解2h,再生率为12.7%.     

一株耐盐性酵母的原生质体化及再生条件的优化研究

对一株耐盐性酵母Zygosaccharomyces rouxii的原生质体化及再生条件进行了实验研究.结果表明:用0.5 mg/mL(10 unit/mL)细胞壁溶解酶zymolyase20T在1.0~1.5 mol/L山梨糖醇渗透压调节剂的浓度范围内,原生质体化率可达99%以上,再生率在2%~11%之间,而且用磷酸钾缓冲液比用Tris-HCl缓冲液再生率高.在山梨糖醇浓度1.5 mol/L,zymolyase20T浓度0.5 mg/mL,磷酸钾缓冲液0.1 mol/L(pH6.0)时,30℃、60 min,再生率达30%以上.     

环孢菌素A产生菌的分子鉴定及其原生质体制备

环孢菌素A高产菌株No.421502经形态学特征和分子标记鉴定,确认为镰孢菌属,命名为Fusariumsp.No.421502.收集Fusarium sp.No.421502孢子刚萌发的幼嫩菌丝体,以0.7 mol/L KCl为渗透压稳定剂,用质量浓度为20 mg/mL的蜗牛酶,30℃80 r/min处理5 h制备原生质体.原生质体为7×105/mL,原生质体形成率为62.8%.制备的原生质体稀释后接入再生培养基,再生率为29.6%.     

白色念珠菌SC5314原生质体制备的研究

通过研究白色念珠菌菌龄、预处理剂、酶解温度、裂解酶种类、酶解时间等不同因素对白色念珠菌SC5314原生质体制备的影响,确定了其原生质体制备的条件:选用菌龄为12 h的菌体,用50 mmol/L EDTA+5%巯基乙醇(体积比)+50 mmol/L Tris (pH=8.0)的复合预处理剂进行预处理,用0.7 mmol/L的NaCl作为渗透压稳定剂,1%的蜗牛酶+1%的纤维素酶+1%的溶壁酶在30 ℃的条件下酶解120 min.在此条件下,其原生质体制备率高达98%.     

利用菊粉产山梨醇酵母融合菌株的构建

介绍高产菊粉酶的克鲁维酵母(Kluyveromycessp.)Y85菌株与产山梨醇的酿酒酵母(Saccharomycescerevisiae)E15菌株,通过属间原生质体融合构建直接利用菊粉产山梨醇的酵母融合菌株.结果认为,以0.1%EDTA-巯基乙醇为脱壁预处理剂,蜗牛酶浓度2%(W/V),酶解温度30℃,E15和Y85两菌株细胞酶解时间分别为40min和30min,原生质体形成率和再生率分别达90%和25%以上.融合的适宜条件为添加30%(W/V)PEG和10mmol/LCaCl2,融合时间为30min,融合率可达2.64×10-6以上.利用两亲株自然性状差异检出融合菌株,并经DNA含量、菊粉酶活性、细胞形态与大小、菌落形态等测定加以确证.其中F27融合菌株在适宜条件下,山梨醇摇瓶发酵产量可达4.87g/100mL,并且具有遗传稳定性能.     

蒙古口蘑与双孢蘑菇原生质体融合育种研究

以蒙古口蘑和双孢蘑菇为出发菌株,研究了酶浓度、酶解时间、菌龄和渗透压稳定剂、再生培养基等对蒙古口蘑和双孢蘑菇原生质体制备和再生的影响.结果表明,蒙古口蘑原生质体制备和再生的最佳条件是,培养5 d的菌丝体用2.5%(w/w)的溶壁酶酶解4 h,渗透压稳定剂为0.6 mol/L KCl,MB为再生培养基,制备率为7.53×1010个/L,再生率为8.4×10-4;双孢蘑菇原生质体制备和再生的最佳条件是,培养5 d的菌丝体用2%(w/w)的溶壁酶酶解3 h,渗透压稳定剂为0.6 mol/L KCl,PQA为再生培养基,制备率为6.96×1010个/L,再生率为7.4×10-4.对两种菌原生质体的释放过程进行形态观察,均为顶端释放.采用双亲灭活原生质体融合技术对蒙古口蘑和双孢蘑菇原生质体融合进行研究,蒙古口蘑原生质体采用热灭活,65℃处理30 min,灭活率达100%,双孢蘑菇采用紫外灭活,在15 W紫外灯下,距离30 cm,处理20 min,灭活率达100%,两菌株按1∶1混合,以30%PEMG(6 000)为促融剂,融合10 min,融合率为5.6×10-5.经遗传稳定性检验,融合菌株的遗传稳定率为80%,从菌落特征、菌丝形态、菌丝生长量、酯酶、游离全蛋白、乳酸脱氢酶、乙醇脱氢酶和过氧化物酶等同工酶方面对融合子进行筛选,获得一株具有双亲性状的融合株.     

异常汉逊酵母原生质体形成和再生研究

采用多因子正交实验确定了一株异常汉逊酵母(Hansenula anomala)原生质体形成和再生的最佳条件。对数前期细胞在1％蜗牛酶、0.1％巯基乙醇(ME)。0.1％EOTA,0.9mol.l~(-1)甘露醇和pH5.4,35℃条件下处理30分钟,原生质体形成率和再生事分别为91.4％和9.31％,原生质体形成率×再生率值最大(8.51％)。     

绣球菌原生质体制备及再生条件的初步研究

为进一步改善绣球菌栽培特性、提高栽培产量,对绣球菌原生质体制备与再生条件进行了初步探索.以绣球菌原生质体再生量为指标,对等渗剂、酶反应温度、pH和反应时间等影响因素进行了优化.结果表明,采用2%的溶壁酶溶解绣球菌菌丝细胞壁,制备原生质体的最佳条件是,以0.6 mol/L蔗糖为等渗剂,在30℃、pH值6.0环境下反应3 h.在此条件下,原生质体的再生量为11 850个/mL.     

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.     

Features of Women's language

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.     

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.     

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     

Call for Papers

<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     

Journal of Donghua University ( English Edition) Contents of Volume 31

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