中胚层的

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。

The part of the embryonic mesoderm, consisting of loosely packed , unspecialized cells set in a

间叶细胞胚胎的中胚层部分，由生长于胶状基质的、结构松散的、无特定功能的细胞组成，这些细胞将会发育成结缔组织、骨、软骨、血液及淋巴系统

Then, under the control of systemic factors, mesenchymal cells aggregate and differentiate to form catilage blastemal elements that prefigure skeletal limb components.

脊椎动物胚胎期骨与关节系统的发生是一种复杂生命现象，起始于中胚层间充质细胞的定向聚集，形成肢芽，然后在一系列作用因子的调控下，肢芽内细胞进一步分化，形成具有骨骼雏形的软骨原基，后者经软骨内骨化发育成骨。

The 28S rDNA molecular phylogenetic trees showed: 1 entoprocts and phylactolaemate ectoprocts constituted a sister group, strenghthening the opinion that entoprocts should be reunited into phylum Bryozoa; 2 the cheilostome gymnolaemates was obviously non-monophyletic; 3 bryozoans itself was polyphyletic beyond any doubt, its main lineages were scattered in different positions of the lophotrochozoan trees; 4 to our great interests, the phylogenetic position of cheilostomes was between the diploblastic and the triploblastic, indicating they may play an important role during the evolution route from the diplobastic to the triploblastic animals.

28S rDNA分子系统树显示，内肛动物和被唇类外肛动物聚在一起并互为姐妹群，支持将内肛动物重新归入苔藓动物门的结论；唇口目裸唇类外肛动物绝非单系发生；苔藓动物本身也不是单系发生的，其主要类群分别位于触手冠担轮动物系统树的不同位置，特别是，唇口目苔藓动物的系统地位介于二胚层动物和其它三胚层动物之间，可能是二胚层动物向三胚层动物演化过程中的一个关键类群。

The present case report explains echographic features of a Mesoblastic Nephroma diagnosed at the 31 weeks of pregnancy and make a brief discussion.

我们的这个病例就提供了一例在孕31周诊断的中胚层肾瘤的回声特征并做了简单的讨论。

Results There were 8 angiomyolipomas, 2 leiomyomas, 2 multilocular cystic nephromas, 1 hemangioma and 1 mesoblastic nephroma. Only multilocular cystic nephroma and leiomyoma have special characteristics that can be determined from RCC.

典型的平滑肌瘤和多囊性肾瘤在CT上有可与肾癌鉴别的特征性表现：平滑肌瘤为规则圆形，边界清楚，密度均匀，CT值略高于肾实质，无钙化，弱强化；多囊性肾瘤为边界清楚的包块，可见边缘锐利含多个分隔的肿块，分隔之间为囊腔，囊内容物的CT值与水相似或稍高，而错构瘤、海绵状血管瘤、慢性肾脓肿、中胚层肾瘤在CT上无法与肾癌鉴别。

Having or characterized by a robust,muscular body build caused by the predominance of structures developed from the embryonic mesodermal layer.

具有运动型体格的由胚胎中胚层发育而来，因结构占优势而促成健壮高大的体型的、或以此为特征的

Of lung cancer generally refers to the substance of the Ministry of lung cancer, often do not contain other pleural mesodermal origin of tumor, or malignant lymphoma, other malignant tumors such as carcinoid tumors, or transfer from other tumors.

肺癌一般指的是肺实质部的癌症，通常不包含其他肋膜起源的中胚层肿瘤，或恶性淋巴瘤、其他恶性肿瘤如类癌，或是转移自其他的肿瘤。

Human basic fibroblast growth factor is a single-chain heparin-binding polypeptide. It is a general regulatory mediator for different cells such as endothelial cells and for other cells of mesodermal and neuroectodermal origin, it stimulates cells proliferation, inducing or delaying differentiation.

人碱性成纤维细胞生长因子是一种单链的具有与肝素结合能力的多肽分子，它能够调节内皮细胞及其它来源于中胚层和神经外胚层等多种细胞的生长、分化、迁移和凋亡，同时是一种重要的血管生成因子，因此具有广泛的临床应用价值。

As similar defects are not exhibited by mice that experience systemic inhibition of NF-B, we postulated that the morphogenetic defects in IKK--deficient mice are not caused by reduced NF-B activity but instead are due to failed epidermal differentiation that disrupts proper epidermal–mesodermal interactions.

因为类似的缺陷没有出现在经历了全身NF-B抑制的小鼠，作者推断IKK缺失小鼠的形态发生缺陷不是由于NF-B活性降低引起而是因为可以破裂专属表皮－中胚层相互作用的表皮分化失败引起。

Breath, muscle contraction of the buttocks; arch body, as far as possible to hold his head, right leg straight towards the ceiling (peg-leg knee in order to avoid muscle tension).

呼气，收缩臀部肌肉；拱起身体，尽量抬起头来，右腿伸直朝向天花板（膝微屈，以避免肌肉紧张）。

The cost of moving grain food products was unchanged from May, but year over year are up 8%.

粮食产品的运输费用与5月份相比没有变化，但却比去年同期高8％。