同体的

Tetraploid embryos could be produced by electrofusion at the stage of two-cell embryos, which could develop to blastocysts followed by fusion of cytoplasm and nucleus and cleavage in vitro. During the fusion of cytoplasm, the DNA methylation levels of the fused embryos are as high as these of two-cell diploid embryos in vivo Then the embryos are rapidly demethylated when the nucleus begin to fuse, resulting in the lowest DNA methylation levels when the nucleus are fused completely. After that, the DNA methylation levels of the fused embryos are gradually increased until the morula stage. However, whereas an asymmetric distribution of DNA methylation is established in vivo-derived blastocysts with a higher methylation level in the inner cell mass than that in the trophectoderm, we can not detect the asymmetric distribution in most in vitro-derived tetraploid blastocysts.

结果表明：利用电融合方法制备的小鼠四倍体胚胎在体外培养体系中经历细胞质融合、细胞核融合及细胞继续分裂发育直到囊胚期的过程，在细胞质融合的时候胚胎卵裂球同体内体外培养二倍体胚胎一样，呈现高度甲基化状态；在细胞核开始融合的时候，甲基化水平急速下降，在细胞核完全融合的时候甲基化水平达到最低点；随着胚胎继续分裂，胚胎甲基化水平逐渐增加，在桑葚胚期甲基化水平最高；但是囊胚期四倍体胚胎内细胞团同滋养层细胞甲基化荧光信号没有差别，这与体内体外培养二倍体囊胚内细胞团细胞甲基化荧光强度高于滋养层细胞甲基化荧光强度不同。

Tetraploid embryos could be produced by electrofusion at the stage of two-cell embryos, which could develop to blastocysts followed by fusion of cyto-plasm and nucleus and cleavage in vitro. During the fusion of cytoplasm, the DNA methylation levels of the fused embryos are as high as these of two-cell diploid embryos in vivo Then the embryos are rapidly demethylated when the nucleus begin to fuse, resulting in the lowest DNA methylation levels when the nucleus are fused completely. After that, the DNA methy-lation levels of the fused embryos are gradually increased until the morula stage. However, whereas an asymmetric distribu-tion of DNA methylation is established in vivo-derived blastocysts with a higher methylation level in the inner cell mass than that in the trophectoderm, we can not detect the asymmetric distribution in most in vitro-derived tetraploid blastocysts.

结果表明：利用电融合方法制备的小鼠四倍体胚胎在体外培养体系中经历细胞质融合、细胞核融合及细胞继续分裂发育直到囊胚期的过程，在细胞质融合的时候胚胎卵裂球同体内体外培养二倍体胚胎一样，呈现高度甲基化状态；在细胞核开始融合的时候，甲基化水平急速下降，在细胞核完全融合的时候甲基化水平达到最低点；随着胚胎继续分裂，胚胎甲基化水平逐渐增加，在桑葚胚期甲基化水平最高；但是囊胚期四倍体胚胎内细胞团同滋养层细胞甲基化荧光信号没有差别，这与体内体外培养二倍体囊胚内细胞团细胞甲基化荧光强度高于滋养层细胞甲基化荧光强度不同。

Tetraploid embryos could be produced by electrofusion at the stage of two-cell embryos, which could develop to blastcysts fellowed by fusion of cytoplasm and nucleus and cleavage in vitro.After fusion of cytoplasm, the DNA methylation levels of the fused embryos was very high as well as two-cell diploid embryos in vivo.Then the embryos was rapiddly demethylated when the nucleus begin to fuse, resulting the lowest DNA methylation levels when the nucleus fused completely.After that, the DNA methylation levels of fused embryos were gradually increased until the blastocysts stage.However, whereas an asymmetric distribution of DNA methylation was established in an vivo-derived blastocysts with a higher methylation level in the inner cell mass than in the trophectoderm, in most vitro-derived tetraploid blastocysts, we can not detect the asymmetric distribution.

结果表明：利用电融合方法制备的小鼠四倍体胚胎在体外培养体系中经历细胞质融合、细胞核融合及细胞继续分裂发育直到囊胚期的过程，在细胞质融合的时候胚胎卵裂球同体内体外培养二倍体胚胎一样，呈现高度甲基化状态；在细胞核开始融合的时候，甲基化水平急速下降，在细胞核完全融合的时候甲基化水平达到最低点；随着胚胎继续分裂，胚胎甲基化水平逐渐增加，在囊胚期甲基化水平最高；但是囊胚期四倍体胚胎内细胞团同滋养层细胞甲基化荧光信号没有差别，这与体内体外培养二倍体囊胚内细胞团细胞甲基化荧光强度高于滋养层细胞甲基化荧光强度不同。

According to the relationship of Yanshan epoch granites and NE ductile shear zones of main structure of this region, and regional isotope chronology data, the granitoids of this region are divided:(1) pretectonic, qnartze monzonite -granites assemblage, representative plutons: Shigujian, Erwan, Egongbao, and Yunfengding;(2) syntectonic granite assemblage, representative plutons: Tiantangzhai, and Jiuzihe;(3) posttectonic granite assemblage, representative plutons: Daguping and Bijiashan. These assemblages differ from precollision , syncollision and postcollision intrusive assemblages.

根据燕山期花岗岩与区内主体构造NE向韧性剪切带的关系，并结合区域同位素年代学资料，将区内花岗岩分为：(1)构造前石英二长岩—花岗岩组合，代表性岩体有石鼓尖、二湾、鹅公包、云峰顶；(2)同构造花岗岩组合，代表性岩体有天堂寨、九资河；(3)构造后花岗岩组合，代表性岩体有大孤坪、笔架山，这里的构造前、同构造和构造后侵入岩组合不同于碰撞前、同碰撞和碰撞后侵入岩组合。

The results showed that POD activity increased at first and then decreased in the skin and flesh of root. The peak occurred at 40 d and 60 d in the skin and flesh, respectively. POD activity in the skin was higher than that in the flesh at 30 d and then contrary results were observed. The higher POD activity was, the more POD isoenzyme was. The pattern of POD isoenzymes was different between skin and flesh at different vegetative growth stages. POD isoenzymes in the skin were composed of five monomers and four dimers while five dimers or two monomers, two dimers and one tetramer in the flesh. POD isoenzymes in the root were mainly acidic. POD localized mainly in the cell walls of periderm, cambium, xylem ray, xylem vessels and primary xylem.

结果显示，心里美萝卜营养生长期肉质根的皮和肉中POD活性均先升高后降低，分别在播种后第40 d和60 d出现峰值，30 d时皮中POD活性高于肉，之后则相反，酶活性最高时同工酶数目也最多，不同时期，皮和肉中同工酶种类不同；皮中POD同工酶由5个单体和4个二聚体组成，而肉中由5个二聚体或2个单体、2个二聚体和1个四聚体组成，均以酸性同工酶为主；组化定位显示POD主要分布在肉质根的周皮、形成层、木射线、木质部导管和肉的初生木质部等的细胞壁附近。

With the use of the dislocation method of complex potential function, this paper studies the interaction between the interface macrocrack and the interface or beneath-interface microcracks by the construction and numerical solution of singular integral equations .

采用复势函数的位错解方法，通过对奇异积分方程的建立和数值求解，研究了界面主裂纹同界面及基体微裂纹之间的干涉。结果表明远场载荷角ψ同Dunder's参数α对界面微裂纹及基体中水平微裂纹同主裂纹干涉的影响都很显著，而ψ对屏蔽区的影响则远小于α对其的影

The delay time of vertical coseismic deformation have positive linear relationship with ep...

断层体垂直向同震形变延迟时间与震中距线性正相关，发生地震同震形变的响应速度约为5.5km/s，反映了在上层花岗岩地层中面波的传播速度；同震位移最大振幅和震中距的对数、震级之间具有明显线性关系，震级越大，同震位移的最大振幅越大；地震震级是断层体垂直同震形变振动持续时间的主要影响因素，震级越大，同震形变振动持续时间越长。

Subunit homodimers were also found existing in heteromeric NMDA receptors formed between NR1 and NR2 subunits.

我们的结果显示，当NR1a，NR2A，NR2B亚单位单独在HEK293细胞中表达时，可以各自形成同二聚体，当与其它亚单位共表达形成NMDA受体时，这些同聚体仍然存在。

A non-singular single integral mathematical model is adopted to calculate the external intermittent and alternative longitudinal magnetic field acquired by single axisymmetrical and cylindrical hollow coil t which is coaxial to electrode and excitated by a revisable pulsed current of square wave t in austenitic stainless steel GTA welding.

针对奥氏体不锈钢外加纵向磁场的气体保护钨极电弧焊接时，与电极同轴的单个轴对称空心圆柱线圈在双向脉冲矩形励磁电流作用下产生的间歇交变纵向磁场，采用无暇点单积分磁场的数学模型，对＊TAW焊接外加间歇交变纵向磁场进行了数值计算，该方法具有模型简单、计算速度快和精度高等优点并讨论了该间隙交变纵向磁场的分布、磁场的均匀性及其纵向分量与径向分量的比率等规律及其对焊接行为的影响，认为横磁分量将削弱GTAW外加纵向磁场的有利作用，影响磁控电弧的焊接质量

During the last decade, many studies have hypothesized that the MADS-box proteins could form specific dimers, which would be further assembled into tetrameric complexes to have more functions. In order to prove whether BCFMADS and CCFMADS genes can interact with each together to form either homodimer or heterodimer, we used an in vitro approach to analyze protein expressions for both genes.

MADS-box基因中，基因并不会单独的表现，而是透过形成同质二元体、异质二元体或是蛋白质复合体来表现其基因的功能性，因此本研究为欲证实BCFMADS以及CCFMADS基因间可否形成同质二元体或是异质二元体，乃利用E。

According to the clear water experiment, aeration performance of the new equipment is good with high total oxygen transfer coefficient and oxygen utilization ratio.

曝气设备的动力效率在叶轮转速为120rpm～150rpm时取得最大值，此时氧利用率和充氧能力也具有较高值。

The environmental stability of that world - including its crushing pressures and icy darkness - means that some of its most famous inhabitants have survived for eons as evolutionary throwbacks, their bodies undergoing little change.

稳定的海底环境─包括能把人压扁的压力和冰冷的黑暗─意谓海底某些最知名的栖居生物已以演化返祖的样态活了万世，形体几无变化。