精子形成

To investigate whether the expression of cdc2 and cyclin B1 in spermatogenic cells during spermatogenesis is actually a temperature dependent event, in situ hybridization, Western blotting and immunohistochemistry analysis were used to study the expression of cdc2 and cyclin B1 in normal and cryptorchid testis. Results showed that heat would differentially hurt male germ cells in different developmental stages during spermatogenesis, especially the pachytene primary spermatocytes. Most of spermatogonia in contralateral cryptorchid testis were not harmed fatally by heat as yet, indicating that spermatogonia could resist to beat to a certain extent. In this case spermatogonia could develop to pachytene/diplotene primary spermatocytes, but they could not acquire the ability to complete the transition from mitosis to meiosis, and then appeared to go through apoptosis. Therefore, we could not find the descendants of meiosis: secondary spermatocytes and round spermatids, elongated spermatids and spermatozoon. The abdominal temperature had no significant influence on the transcription of cdc2 and cyclin B1 in the spermatogonia and pachytene/diplotene primary spermatocytes. In normal rabbit testis, cyclin B1 increased in the pachytene/diplotene primary spermatocytes before meiosis and reached its peak in the spermatids.

为了解精子正常发生过程中cdc2和cyclin B1表达的低温依赖性，我们利用原位杂交和免疫组化等方法，研究了正常和隐睾精子发生过程中cdc2和cyclin B1的转录和翻译调控活动，结果表明：（1）热对各阶段的雄性生殖细胞都有损害，粗线期的初级精母细胞尤为敏感，实验性隐睾内的精原细胞尚未完全受到"致命"影响，说明精原细胞对热有一定的耐受性，但即使成为粗线期／双线期初级精母细胞，却未能获得由有丝分裂过渡到减数分裂的能力，呈现不同程度的凋亡，所以在整个切片中找不到源自减数分裂的产物----次级精母细胞、圆形精子细胞，更谈不上长形精子细胞和精子的形成；（2）腹腔高温未明显地影响隐睾精原细胞和粗线期/双线期初级精母细胞中cyclinB1和cdc2的转录，说明高温并不是通过影响cyclin B1和cdc2的转录活动而导致生精过程阻断的；（3）正常兔睾丸组织中，〓在精原细胞和粗线期／双线期精母细胞中均有表达：cyclin B1蛋白在减数分裂前期的粗线期／双线期初级精母细胞中的表达量增加，于变态末期的精子细胞中达高峰。

A result of these foods with high lysine is an essential element of spermiogenesis.

因这些食物中含赖氨酸高，是精子形成的必要成分。

The spermatogenesis in worker included spermatogonia, primary speramtocyte, second spermatocyte and spermatid, but mature sperm was not found.

工蚁精子的发生过程包括精原细胞时期和精母细胞时期，并形成了精细胞，但未形成精子。

Fig.7 After the Sperm formed,it leaves the cytoplasmic massof spermatid 8300

图7。精子形成后与胞质间桥脱离的纵断面，8300

The spermatozoa are embeded in a extracellalar matrix composed of high dense fibrils matrix and flocculent and concentric vesicles similar to that in the primary spermatophore layer, but the later lack of spermotozoa. The flocculent and concentric vesicles are often seen to release their contents around the main body of spermatozoa. The spermatozoa may absorb the contents to form vesicular zone and membrane zone in sperm nucleu. The secondary spermatophore layer is distinctly subdivided into inner region and outer region. The loose outer region consists of canaliculated reticulum and large flocculent vesicles.

输精管内的精荚为管状，由精子群、精荚基质及初级精荚壁和次级精荚壁组成，初级精荚壁与精荚基质是相连续的，它们之间无明显界限，两者均由电子密度较高的纤丝状基质和絮状泡和同心圆泡组成，但后者不含精子，后者中的絮状泡和同心圆泡常在精子主体部周围释放内含物，可能与形成精子细胞核中的泡状带和膜状带有关，在交配后的雌虾，其头胸部腹面上粘着的精荚中，其基质内已不见絮状和同心圆泡，仅见稀疏的纤丝。

These data suggested that the centrin isoforms played different roles in different stages of spermatogenesis. The centrin-1 gene was revealed to be relevant to the centriolar translocation to the posterior pole of cell and the elaboration of flagellum during spermiogenesis, while the centrin-2 and centrin-3 might play roles in spermatogonial mitosis but were not involved in the spermatid differentiation process.

这些结果提示，Centrin同源基因在精子发生的不同阶段发挥不同功能，其中Centrin-1与精子细胞分化期的中心体后移、鞭毛的生成及精子中轴形成可能密切相关，Centrin-2和-3则可能在精原细胞有丝分裂中起作用，而与精子细胞变态分化无关。

And there are essential genes for sperm formation on the Y chromosome.

生殖细胞的性别主要是由生殖腺中体细胞的微环境决定的。Y染色体上存在精子形成所必需的基因。

The testis index, testis volumes were same as the annual changes of testis mass. The curves of annual variation were all unimodality.2 The spermatogenetic cycle of Myospalax cansus comprises seven stages with significant features: Stage I , from February to April, the testis were at the stage of spermatogonia proliferation. In this period, testis index and the number of spermatogonia began to rise. Other spermatogenic cells had not yet formed; Stage II to III, from March to April, primary spermatocyte meiosis period. The testis index was highest in this stage, and spermatogenic cells were in spermatocyte stage, the primary spermatocyte meiosis generated to secondary spermatocyte; Stage IV, from April to May, spermatocytes continued to split, germ cells appeared in seminiferous tubules; Stage V, in May, sperm formation, spermatids of seminiferous tubules were transformed to spermatozoa, a large number of sperms existed in the lumen; Stage VI, spermatozoa emission period, from May to June, testis index were a significant drop and mature spermatozoa excluded gradually; VII, the testicular activity ceased basically from July to September, November to January of the following year, the spermatogenic activity ceased completely. Therefore, Myospalax cansus are animals of seasonal reproduction, spermatogenesis cycle is discontinuous type.

睾丸系数、体积和重量的年周期变化规律一致，变化曲线呈现单峰型。2甘肃鼢鼠雄性生殖腺的年周期活动由7个特征明显的时期构成：Ⅰ期，2～3月份，精原细胞增殖期，睾丸系数开始上升，精原细胞进行有丝分裂，其他生精细胞尚未形成；3～4月份为Ⅱ～Ⅲ期，初级精母细胞成熟分裂期，睾丸系数达到最大，生精细胞大多处于精母细胞阶段，初级精母细胞减数分裂生成次级精母细胞；Ⅳ期，4～5月份精母细胞继续进行分裂，精细胞在生精小管内出现；Ⅴ期，5月份，精子形成期，曲细精管中精细胞变态成精子，在管腔中存在大量的精子；Ⅵ期，精子排放期，5～6月份，睾丸系数显著下降，成熟精子从生精小管上脱离，逐渐排除；Ⅶ期，精原细胞停滞期，7～9月份睾丸生精活动基本停滞，11～翌年1月，生精活动完全停止。

Spermatogonial stem cells divide continuously to support spermatogenesis throughout postnatal life and transmit genetic information to the next generation.

精原干细胞在人出生后可以连续分裂以支持精子形成，将遗传信息传递给下一代。

In conclusions,(1) The pronuclear formation was asynchronous after ICSI in buffalo, the female pronuclear formed 3 hours earlier than male pronuclei;(2) After ICSI and activation, Culture of oocytes in 1.9mmol/L 6-DMAP for 3 hours can improve their subsequent embryonic development;(3) Treatment of sperm with 5mmol/L DTT can promote sperm decondensation;(4) Dead sperms can be used for ICSI in buffaloes;(5) Treatment of sperm with GSH can improve the efficiency of ICSI in buffaloes.

以上结果表明：(1)水牛精子胞质内显微受精的雌、雄原核发育不同步，雌原核比雄原核早3h形成；(2)水牛卵母细胞ICSI和激活后用1.9mmol／L 6-DMAP培养处理3h能提高其胚胎发育率；(3)DTT预处理水牛精子能提高其ICSI后的精子解聚率；(4)死精子能用于水牛卵母细胞的ICSI；(5)GSH预处理水牛精子有助于提高其ICSI后的囊胚发育率。

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。