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A preliminary report on in vitro sperm capacitation and egg-penetration of giant panda is briefly presented. The panda spermatozoon consists of head, neck and tail, just like the spermatozoa of other animals. Before capacitation sperm heads clusterd together and dispersed after capacitation. They were then able to swim straight forwared. During the time of in vitro capacitation the plasm membrane of the sperm head was first expanded tov arious degrees, then disintegrated, and finally became detached. The electro-dense material in the acrosome appeared in small clumps with high density. Extensive vesiculation occurred between the bi-layered acrosome membranes and thus led to disintegration. Vesiculation in panda sperm differs from that reported in hamsters. When the capacitated panda spermatozoa came into contact with the hamster eggs, the region between the acrosome collar and postacrosome cap first fused with the egg membrane followed by the penetration of the nucleus into the cortex of the egg. Some o  相似文献   
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本文通过竞争结合实验和电子显微镜放射自显影定位的研究,显示了小分子肽类激素不仅能进入鲮鱼(cirrhrinus molitorella)垂体的促性腺激素细胞内,并且进一步观察到125碘标记的LH-RH尚能通过核孔进入细胞核内。因此提出肽类激素有直接作用于染色质的可能性,这一事实有助于了解肽类或蛋白质激素在细胞或分子水平上的作用原理。  相似文献   
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大熊猫精子体外获能和异种穿卵的超显微结构研究   总被引:1,自引:0,他引:1  
大熊猫精子体外获能前,精子头部发生群集成缗钱状结构,获能后精子作活跃直线的超激活运动。获能过程中头部质膜先膨胀,随后破裂,顶体内致密物质浓缩成小团块,双层顶体外膜出现囊泡化引起顶体反应,从而顶体逐渐瓦解脱落,但顶体内胰仍包在核膜之外。 大熊猫精子获能和顶体反应后并能与地鼠卵子相互作用,在顶体领与后顶体帽连接处同卵膜先开始融合,接着可以穿入卵内。地鼠卵被大熊猫精子穿入后,卵表面出现明显的异常形态变化。  相似文献   
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