条石鲷的胚胎发育观察

对条石鲷早期发育(从受精卵到初孵仔鱼)的形态特征进行过程观察,描述了各发育时期的形态特征和发育速度.条石鲷的受精卵为圆球形浮性卵,透明,微黄色.在水温23.6～24.8℃,盐度28.5条件下,受精卵约经30 h32 min孵出仔鱼.实验记录了从受精卵到出膜后6 d的26个发育时期的特征及发育时间,拍摄了26张具有代表性的胚胎和仔鱼图片,胚胎发育可分为20个发育期.初孵仔鱼全长2.01 mm(1.92～2.08 mm),孵出45 h后卵黄囊完全吸收.     

淡水驯化后大鳞鲃胚胎发育观察

通过人工授精获得大鳞鲃(Barbus capito)受精卵,并在23℃~26℃的孵化条件下,详细观察了大鳞鲃胚胎发育及未受精卵的特征.结果显示,大鳞鲃受精卵为漂流性卵(半浮性卵),卵径为(1.55±0.1)mm,吸水后卵膜膨大,卵径达到(4.3±0.2)mm.在水温23℃~26℃的条件下,胚胎发育总历时为47 h 29 min,胚胎发育过程所需总积温为1 081℃~1 222℃.大鳞鲃受精卵卵裂方式与其他鲤科鱼类一样,属于盘状卵裂.根据胚胎发育各阶段的形态特征,将其划分为胚盘隆起、卵裂、囊胚、原肠胚、神经胚期至尾芽期和胚动期至孵化期等6个连续发育阶段,22个时期.未受精卵入水后吸水膨胀,由原生质集中形成"胚盘",但无如两细胞卵裂的现象;未受精卵的突起或分裂球陆续脱离胚盘会形成类似受精卵囊胚末期时的"假囊胚".研究结果有助于提高大鳞鲃人工繁育效率及对孵化条件及时调控处理,有助于大鳞鲃亲鱼受精率计算方法的掌握.     

鮸状黄姑鱼与大黄鱼人工杂交子代的胚胎发育

以Mian状黄姑鱼为母本、大黄鱼为父本的人工杂交试验表明：在温度17－20℃、盐度29．9－30．8的条件下，杂交卵经39.9h孵出，受精率为58．9％，孵化率为1．4％，仔鱼存活18d。对照组Mian状黄姑鱼受精率95％，受精卵孵化率56％。杂交组受精卵的胚胎发育与母本Mian状黄姑鱼的胚胎发育主要差别为：杂交卵在进入原肠期时，多数胚胎发育速度明显变慢，囊胚不能正常下包，胚胎畸形率较高。     

唇(鱼骨)(♀)×花(鱼骨)(♂)杂交子一代胚胎发育

以唇(鱼骨)为母本,花为父本进行属内远缘杂交,观察和记录了杂交F1受精卵胚胎发育情况,具体描述了各个时期的形态特征.结果表明,受精卵为粘性卵,卵径为2.50～2.80 mm,在水温在(20±1)℃条件下,受精后55 rain,胚盘形成;1 h 35 min,细胞开始分裂,进入卵裂期;5 h 05 min,囊胚层形成,进入囊胚期;10 h 30 min,胚层下包,形成胚环,进入原肠期;17 h 25 min,神经板形成,胚体侧卧,进入神经胚期;19 h 15 min,胚孔关闭,进入胚孔封闭期;22 h 25 min,进入器官形成期;94 h 10 min,仔鱼开始出膜.研究认为唇(鱼骨)(♀)×花(鱼骨)(♂)杂交F1受精卵与母本胚胎发育时序和形态特征基本相似.     

鲈鲤胚胎发育特征观察

观察了水温（18±0．5）℃条件下,鲈鲤[Percocypris pingi pingi（ T chang ）]的胚胎发育特征。结果显示：成熟鲈鲤卵呈球形、桔黄色,为粘性卵,卵径2．2mm,卵膜遇水膨胀后,最大外膜径达3．2-3．8mm。受精卵在水温（18±0．5）℃条件下,受精2h28min后开始第1次卵裂,受精后45h23min开始形成器官,受精后126h28min孵出仔鱼。初孵仔鱼全长为10．4mm,卵黄囊大而侧扁。根据胚胎发育过程的形态特征,可将鲈鲤胚胎发育过程分为受精卵、卵裂、囊胚、原肠胚、神经胚、器官发生和出膜7个连续阶段。32个时期。     

豫北地区大鳞副泥鳅胚胎发育的观察

目前泥鳅和大鳞副泥鳅的养殖热潮正在全国范围内兴起,优良新品种的培育早已经为养殖者所期待.胚胎发育过程特征的研究是进行新品种培育的基础工作.对产自豫北地区的大鳞副泥鳅的胚胎发育过程进行了连续观察,对其各个胚胎时期的发育特征和持续时间进行了记录.结果表明从受精卵到出膜共划分为6个阶段和卵裂期、囊胚期、原肠期、神经胚期、肌节期、尾芽期、胚动期、出膜前期、孵出期、眼黑色素期等10个连续的典型时期,在23℃时胚胎发育历时共24 h 20 min.     

遮目鱼的诱导产卵

以绒毛膜促性腺激素(HCG)和鲤鱼脑垂体制剂(CPH)对遮目鱼进行诱导产卵。每次注射剂量HCG 10000国际单位,CPH 100亳克。每尾鱼注射两次,两次间隔时间为24小时。注射药物后,三尾雌鱼产了卵,其中一尾雌鱼所产之卵经人工授精,部分受精卵通过胚胎发育阶段而孵出了鱼苗。     

团头鲂的胚胎发育与观察方法优化

通过人工繁殖获得团头鲂受精卵,在体视显微镜下对其胚胎和早期仔鱼发育过程进行了连续观察、拍照与测量.结果显示,团头鲂受精卵呈圆球形,具黏性,卵径(1.18±0.09)mm;在水温(21±1)℃条件下,团头鲂胚胎发育从受精到孵化历时39h10min,经历了胚盘形成、卵裂期、囊胚期、原肠胚期、神经胚期、器官形成期和出膜期7个发育阶段;初孵仔鱼体长(3.44±0.29)mm,出膜后第4d仔鱼鳔完全充气,卵黄囊消失;观察时,受精卵至尾鳍出现期胚胎置0.7%生理盐水中,肌肉效应期和后面各时期的胚胎经4%多聚甲醛固定后置3%甲基纤维素中拍照可获得良好效果.该工作为研究团头鲂胚胎早期发育过程提供了实时和动态的图像资料,并为鱼类胚胎发育观察提供了基本技术参考.     

泰山赤磷鱼酯酶同工酶(EST)的研究

运用垂直板聚丙烯酰胺凝胶电泳技术,对泰山赤磷鱼早期发育不同时期(未受精卵、受精卵、原肠晚期、色素期)和成体眼、脑、心、肌、肝、肾6种组织酯酶进行研究,结果表明(1)泰山赤磷鱼酯酶同工酶在未受精卵和早期胚胎发育时期均表达,并且酶谱和酶活性有差异,该酶的激活时序与动物胚胎发育中的细胞分化密切相关;(2)泰山赤磷鱼酯酶同工酶具有明显的组织特异性,酯酶同工酶基因表达与组织来源和细胞分化密切相关.     

罗氏沼虾个体发育之初——受精卵特性的研究

采用石蜡切片和生化方法研究了罗氏沼虾(Macrobrachium rosenbergii)受精卵的特性。结果表明：受精卵中央区是一团致密的卵黄物质,卵表面初级卵膜内是一层细胞质。表层细胞质与中央区之间是连接紧密的卵黄颗粒。中央区与外周卵黄颗粒紧密相连,同时也透过卵黄颗粒间的细胞质与表层细胞质相连。卵黄物质的组成以蛋白质(18．67±0．22(μg/卵))和脂类(13．52±0．27(μg/卵))为主,分别占受精卵干重的45．86%和33．21%。在受精卵期较高的淀粉酶活力说明糖类在此期为主要的能源,迅速为受精卵的发育提供能量,蛋白酶类酶活力也较高,分解卵黄蛋白以供能,脂类在受精卵期不是主要的能源。罗氏沼虾受精卵期蛋白SDS-PAGE显示了包含卵黄磷蛋白两个亚基在内的75．6～105KD区域内的蛋白亚基含量丰富,是受精卵期蛋白质的主要成分,也是胚胎发育时期的蛋白营养源,此外,其他分子量的蛋白亚基种类也较多。     

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.     

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     

An affordable accurate evaluation of the binding conformations predicted by molecular docking studies in bio-system

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     

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

正~~