精原细胞

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。

The results show that the CD29, CD49, CD90 express in the gonium and the primary spermatogenous, but there are not expression in the oocyte, the second spermatogenous and the spermatocyte.

研究结果表明，CD29， CD49， CD90在雌性生殖腺各级卵母细胞中均不表达，位于生殖褶边缘的性原细胞中可见表达；在雄性生殖腺的初级精原细胞中表达，但在成团分布的次级精原细胞、各级精母细胞中均未表达。

Conclu sion:(1)Surface densities of PCNApositive cells reached their peaks on 14th day after birth,but the number of apoptotic cells reached its peaks on 21st day p ostnatal,so the apoptotic peak was late the proliferating peak for a week,and related to the particular period in cycle of seminiferous epithelium;(2)The spe rmatogium were found move from center to the periphery of the seminiferous tubule and arrange disorder to order;(3)The spermatogonium remained replicating activ ity of DNA during the developing stage.

生精细胞凋亡的高峰要滞后其增殖峰1周左右，而且与其所处生精周期的特定阶段有关；（2）精原细胞在胚胎发育过程中向曲细精管周边迁移，其排列由无序到有序；（3）在生后各发育阶段中，精原细胞始终保持DNA复制的能力。

While under the ultrastructure, the spermatogonium can be distinguished as primary spermatogonium and secondery spermatogonium; in addition, the mature sperm has a head, a midpeice and a tail, and the "9+3" canaliculus tail has side fin in it.

超微结构下精原细胞分为初级精原细胞和次级精原细胞，成熟精子分头部、中片和尾部3个部分，尾部有侧鳍，具"9+3"式微管结构。

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。

The apoptosis of 80 mg/kg ﹒ d group was mainly located in spermatogenous cell and first spermatocyte; the apoptosis of 120 mg/kg ﹒ d group was mainly located in spermatogenous cell , first spermatocyte and spermatocyte of the second order; the apoptosis of 240 mg/kg ﹒ d group was mainly located in spermatogenous cell and first spermatocytes, and seemingly, the apoptosis located in first spermatocyte was dominant; whereas the apoptosis of 480 mg/kg ﹒ d group was located in all levels spermatogenic cells.

结果表明：各试验组小鼠生精细胞凋亡指数随着浓度的升高有增加的趋势，而且与对照组差异显著（ P ＜0.05或 P ＜0.01）。80 mg/kg · d 组凋亡细胞主要定位于精原细胞和初级精母细胞；120 mg/kg · d 组凋亡细胞主要定位于精原细胞、初级精母细胞和次级精母细胞；240 mg/kg · d 组凋亡细胞主要定位于精原细胞、初级精母细胞，以初级精母细胞为最多；而480 mg/kg · d 组凋亡细胞定位于各级生精细胞。

They can reach 72.04% and 84.5% separately(P.05). 2. The methods such as Percoll uncontinuous density gradient centrifugation, isolation according to the different adhesiveness can be used to isolate and purify rabbit SSC effectively. Spermatogonia mainly distribute between the gradient 27% to 35%(density between 1.0410g/ml to 1.0508g/ml).

Percoll 不连续密度梯度离心和差异粘附等方法可以有效的对兔精原细胞进行分离纯化，其中精原细胞主要分布于密度梯度为27%-35%(密度 1.0410g/ml~1.0508g/ml)的带间，此带中精原细胞的纯度平均达到 60.42%(P.01)。

Strong expression of nanos 1 mRNA was detected in spermatogonia and relatively weaker signal was found in primary spermatocytes but no nanos 1 mRNA expression was observed in spermatids. The results suggested that nanos 1 may play an important role in maintenance and functioning of the germline stem cell—oogonia and spermatogonia.

在斑马鱼精子发生中， nanos1 mRNA可在精原细胞和初级精母细胞中检测到。nanos1 mRNA的阳性信号在精原细胞中极为强烈，在初级精母细胞中较为微弱，而精子细胞中没有阳性信号。

Stage I of both male and female stone flounder appears only once in all its life, and the germ cells are comprised by spermatogonia or oogonia. The gonad from Mar to Aug keeps at stage II. The gonad index of testis at this stage is 0.037%, and the amount of spermatogonia is increased quickly. There is some linear germ plasm in the cytoplasm of spermatogina. In ovary at this stage it is mostly composed by oocyte of phase 2 which the character is the appearance of yolk nucleus, and no zona radiate in membrane. The mean GI of ovary is 1.95%. From Sep to Oct gonad is at stage III which testis is composed by lots of spermatogina and few spermatocytes, and the mean GI of testis at this stage is 0.086%. In ovary the ooctyes at phase 3 are in dominate position, the yolk nucleus disappear. And the GI of this stage is 3.35%. Both testis and ovary are at stage IV in Nov. hi testis the germ cells are in spermiogenesis, and the mean GI is 0.93%. hi ovary the oocytes are mostly at phase 4, which are filled in the cytoplasm with vitellin granule, and the zona radiate in membrane begins to formation. Nucleus moves to one side of the oocyte gradually. The mean GI of ovary at this stage is 9.37%.

在每年的3月-8月期间性腺处于Ⅱ期，此期精巢中精原细胞明显增多，胞质局部可见有线状的生殖质存在，平均成熟系数为0.037％；卵巢中以2时相卵母细胞为主，可见细胞质中出现强嗜碱性的卵黄核，细胞外由一层滤泡细胞包围，但尚无放射带，平均成熟系数为1.95％。9月-10月期间性腺处于Ⅲ期，此期精巢中仍有大量精原细胞，同时可见部分精母细胞，平均成熟系数为0.086％；卵巢中以3时石鲜孟加限加$玩印面n洲匆s性腺发生、分化及发育的周年变化相卵母细胞为主，细胞质中的卵黄核己消失，平均成熟系数为3.35%。11月性腺处于IV期，此期精巢内精细胞正处于不同的形成过程中，平均成熟系数为0.93%；卵巢中以4时相卵母细胞为主，胞质中充满染成桔红色的卵黄颗粒。

Histologically, the seminiferous tubules contained numerous Sertoli cells and more Sertoli-spermatozoa complexes, accompanied by the depletion of Leydig cells with deeply stained nuclei. Mature spermatozoa were stored up in the epididymis, but only a few in the efferent ducts. In the second place was testicular atrophy（32/120; 26.7%）. The seminiferous tubules showed moderate to severe inactivity of spermiogenesis with evidence of only spermatogonia, spermatocytes and Sertoli cells. The Leydig cells were obviously decreased in numbers associated with decrease of lipid droplets in their cytoplasms. Testicular hypoplasia was the third disorders（22/120; 18.3%）. Only a few spermatogonia and Sertoli cells appeared without any spermiogenesis. The associated changes was decreased in Leydig cells and fibrous hyperplasia in the interstitium.Epididymal stones were sometimes found（12/120; 10%）. Grossly, yellowish-white nodules with various sizes and firm in consistency were observed in the epididymis and the front efferent ducts. Microscopically, the epididymal ducts were dilated with voluminous spermatozoa storage, even showed calcification in severe cases. The deposited calcium salts were stained positively by Von Kossa and Alizarin red methods.Amyloidosis was also detected in 10 roosters（8.3%）. Eosinophilic, homogeneous, amyloid-like substances were deposited mainly in the testicular interstitium and the periphery of blood vessels. These substances showed positive reaction by Congo red staining. Five roosters（4.2%）had Marek's lesions in the testis, epididymis and peripheral nerves with infiltration of pleomorphic lymphocytes. Only one case showed epithelial necrosis of seminiferous tubules accompanied by fibrous proliferation in the interstitium.

结果发现，在总共搜集的120个病例中，其中因年老所导致的产精力不佳为最多，占38例（31.7%），於镜下可见大量精虫黏附於Sertoli cell的表面，并可见Sertoli cell数量明显增多而Leydig cell明显减少，且其细胞核呈现浓染的现象，而在其副睪中仍可见到成熟精虫蓄留於管腔中，但在其输精管内却只有少量精虫存在；其次为睪丸萎缩，占32例（26.7%），镜下可见中度至重度无造精作用，其生精小管中只见到精母细胞、精原细胞及Sertoli cell存在，但Leydig cell数量明显减少且其细胞质内的脂质也明显减少；睪丸发育不全，占22例（18.3%），於生精小管内只见到精母细胞及少量Sertoli cell存在，不见造精细胞分化，於生精小管间质可见Leydig cell减少并伴随结缔组织增生；副睪结石，占12例（10%），肉眼下可在副睪及输精管前段见到黄白色大小不一的结节，触感坚硬，於镜下可见副睪管扩张并有大量成熟精虫蓄积，严重时可见钙化现象，以Von Kossa及茜素红染色均呈阳性反应；类淀粉沉著症，占10例（8.3%），镜下在睪丸间质及血管周围可见粉红均质样的物质沉积，以刚果红染色成阳性反应；马立克病，占5例（4.2%），镜下可在睪丸、副睪实质及周边神经内均可见到嗜碱性大小不一的淋巴样细胞浸润；睪丸坏死，占1例（0.8%），镜下可见生精小管上皮细胞坏死脱落及间质结缔组织增生。

It has been put forward that there exists single Ball point and double Ball points on the symmetrical connecting-rod curves of equilateral mechanisms.

从鲍尔点的形成原理出发，分析对称连杆曲线上鲍尔点的产生条件，提出等边机构的对称连杆曲线上有单鲍尔点和双鲍尔点。

The factory affiliated to the Group primarily manufactures multiple-purpose pincers, baking kits, knives, scissors, kitchenware, gardening tools and beauty care kits as well as other hardware tools, the annual production value of which reaches US$ 30 million dollars.

集团所属工厂主要生产多用钳、烤具、刀具、剪刀、厨具、花园工具、美容套等五金产品，年生产总值3000万美元，产品价廉物美、选料上乘、质量保证，深受国内外客户的青睐