微量元素对提高奶牛受胎率的研究

对281头饲养管理正常、无繁殖系统疾病的高产奶牛进行了产后补饲微量元素的试验研究．130头补饲的母牛(试验组)比151头未补饲的母牛(对照组)配种两个情期受胎率提高16．1个百分点．产后60d内母牛发情试验组比对照组发情母牛比率提高15．4个百分点．     

胎衣不下对奶牛产后繁殖力的影响研究

通过对574头初产母牛和1269头经产母牛泌乳期资料的生物统计学分析,研究胎衣不下对产后奶牛繁殖力的影响,同时按母牛是否伴发子宫炎或(和)卵巢囊肿分组,比较了它们可能对产后繁殖力的影响。患子宫炎或(和)卵巢囊肿的母牛,其胎衣滞留时间的长短对产后繁殖力无明显影响。单纯胎衣滞留的初产母牛,首次配种受胎率明显降低。经产母牛中,胎衣滞留超过5天者,首次配种受胎率降低25％(P<0.05),空怀时间延长17天(P<0.05);若胎衣滞留时间超过7天,首次配种时间延迟21天(P<0.05),首次配种受胎率降低35％(P<0.01),空怀时间延长66天(P<0.01)。     

促孕散治疗奶牛卵巢疾病引起不孕症的研究

本研究用促孕散对奶牛持久黄体和卵巢静止进行分组治疗，并与激素治疗作对比。结果表明，促孕散治疗持久黄体试验牛发情有效率为97．62％，配种受胎率为90．24％；促孕散治疗卵巢静止试验牛发情有效率为92．59％，配种受胎率为92．0％；经氯前列烯醇治疗持久黄体试验牛的配种受胎率为71．11％，经绒毛膜促性腺激素治疗卵巢静止试验牛的配种受胎率为58．33％。由此说明，促孕散在治疗奶牛持久黄体和卵巢静止性不孕症中效果显著。     

牦母牛发情期阴道粘液pH值、粘液结晶、细胞学变化规律与受胎率关系的研究

对１９头健康牦母牛在发情期中阴道粘液的变化情况进行了研究，结果表明，在友情盛期，牦母牛阴道粘液ｐＨ值为７；１２±０．３１，阴道分泌物抹片镜检可见大量无核上皮细胞，少量有核上皮细胞，很少见白细胞，并有５２．６％牛只出现不同形状的粘液结晶；在发情末期，阴道粘液ｐＨ值为６．９７±０．２７，镜检可见上皮细胞减少，白细胞增多，粘液结晶出现率明显减少仅占３１．２％；受试１９头牦母牛中，受孕数１３头，受胎率为６８．４％，其中，１０头出现粘液结晶的发情牦母牛全部受孕（１００％），９头未发现粘液结晶的牛只仅受孕３头（３３．３％），二者差异极显著（Ｐ＜０．０１），由此看出，牦母牛在友情期中阴道粘液结晶的出现率与会胎率成正相关。该研究结果为准确判定牦母牛发情期，指导过时输精及提高杂交受胎率，提供了简便易行的方法和基础参考数据。     

山羊手术法胚胎移植对供受体母羊重复使用的影响

采用手术法对白绒山羊进行胚胎移植，探讨手术对供受体母羊重复使用的影响。结果：１９９１￣１９９４年４年中，用于第１、２、３、４次超排（ＦＳＨ＋ＬＨ）的有效供体母羊数为９１只、４３只、７只和２只，手术取胚的胚胎回收率分别为７０．１％、８２．７％、７９．６％和６３．６％。供体母羊手术取胚后，在下１￣２情期中发情时进行人工授精，用于第１、２、３、４次手术后人工授精的所有组合的供体母羊数为１３６只、５９只、     

伊莎褐商品代蛋鸡育成后期体重对早期产蛋性能影…

对９４５只１２５日龄的伊莎商品蛋鸡不同体重组进行早期（１９－２５周龄）产蛋性能的观察结果：体重在开产前达到１６００ｇ以上时提前开产，达５％、５０％和８０％的产蛋率日龄，体重最重的Ａ组比Ｂ组分别提早７、４和１天，比Ｃ组分别提早１４、７和４天；试验期内的产蛋量，Ａ组比Ｂ组多产蛋６４９枚，合４６．２４ｋｇ，比Ｃ组多产１６８３枚，合１０９．６５ｋｇ；蛋重与体重呈正比，平均每蛋重，Ａ组比Ｂ组多１．４６ｋｇ，     

牛体外受精胚胎移植的应用研究

探讨了利用牛ＩＶＦ技术,在国外生产纯种肉牛胚胎运用国内进行大批量移植后受体母牛的妊娠率及产犊情况,共移植受体母牛１５８头,妊娠率（９０ｄ）为２１．４％￣４８．５％,共计产纯种犊牛５５头,５￣８日龄胚移植给发情第７ｄ的母牛能够得到较高的妊娠率（４３．８％￣５０．０％）,受体母牛在前两交伯移植妊娠率（３０．０％￣３５．０％）,明显高于第三次（１５．４％）以后的妊娠高,研究结果证实,在国外生产的的占ＩＶ     

奶牛胚胎早期死亡的预防

怀孕母牛流产原因很多，如习惯性流产、损伤性流产等，但多数属胚胎早期死亡，死亡率可达20％。30％．胚胎早期死亡大致可分为两个时期．一是在配种后的8一12天之间．另一个足在配种后40天左右。这是冈为母牛正常发情周期为20-21天，如果母牛配种后经30天左右和40天以上出现再发情现象的，这就可以认为这些母牛具有胚胎早期死亡的可能性。     

奶牛繁殖中的几个问题

奶牛的发展很大程度上取决于牛的繁殖,繁殖力就是奶牛的生产力,如果奶牛不能有效的繁殖,也就失去了饲养价值,而被淘汰。奶牛因不孕症淘汰占母牛淘汰率的比例达32％,因此,搞好奶牛的繁殖对增加奶牛头数,产奶量的提高和获得好的经济效益至关重要。目前在石河子垦区,规模化大牛场,出现头胎母牛产后90—120天不发情,有些是久配不孕,还有些配种后2—3上个情期又返情等,     

灭活与未灭活发情母牛血清对牛体外受精卵发育的影响

通过在成熟培养液和发育培养液内添加灭活或未灭活发情母牛血清（ＯＣＳ）探讨了血清灭活与否对牛体外受精（ＢＩＶＦ）卵发育的影响，在卵母细胞成熟培养实验中，两个组分别添加１０％灭活、未灭活发情零日母牛血清（Ｄ＿０ＯＣＳ），另一组为不加血清的对照组。三个处理组的卵裂率分别为７４．８％、７６．５％和５０．２％（Ｐ＜０．０１）。囊胚发育率分别为２５．９％、１８．３％和４．８％（Ｐ＜０．０５）。前两个处理组间无显著差异，但二者的各项发育指标均显著高于对照组。在发育培养液内分别添加５％灭活或未灭活发情第五日母牛血清（Ｄ＿５ＯＣＳ）。两个处理组的卵裂率分别为７６．７％和７２．０％，囊胚发育率分别为２４．５％和２０．１％，二者间无显著差异，结果表明：牛卵母细胞的成熟过程中，血清的添加是必须的。未灭活ＯＣＳ同样可以促进ＢＩＶＦ卵的体外发育，但其效果仍不如灭活的ＯＣＳ．     

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

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