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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。

Two polar nuclei move to the micropylar end before sperm is released in a gap between the egg cell and central cell and subsequently taking off cytoplasm one after another. The sperm nucleus moving to the egg nucleus runs faster than the one to the polar nuclei. It fuses with the polar nuclei that are moving towards the antipodal cells at the chalazal end.

精子释放前，两极核移向卵细胞的合点端；两精子释放于卵细胞与中央细胞的间隙后，先后脱去细胞质，然后分别移向卵核和极核，移向卵核的精核快于移向极核的精核；精核与两极核在向反足细胞团方向移动的过程中完成雌雄核融合。

Two polar nuclei move to the micropylar end before sperm is released in a gap between the egg cell and central cell and subsequently taking off cytoplasm one after another. The sperm nucleus moving to the egg nucleus runs faster than the one to the polar nuclei. It fuses with the polar nuclei that are moving towards the antipodal cells at the chalazal end, Images showed the fusion process of male and female nuclei and polyspermous fertilization.

精子释放前，两极核移向卵细胞的合点端；两精子释放于卵细胞与中央细胞的间隙后，先后脱去细胞质，然后分别移向卵核和极核，移向卵核的精核快于移向极核的精核；精核与两极核在向反足细胞团方向移动的过程中完成雌雄核融合。

At postnatal 1st week immunopositive reaction of NGF was detected mainly in sustentacular cells and the spermatogonia also showed positive staining. NGF positive staining in the testes was observed in interstitial cells, spermatogenetic cells, sustentacular cells and Leydig cells at 3rd week. After the postnatal 5th week, NGF-positive immunostaining was also detected in intersitial cells and spermatogenetic cells, but the intensity of reaction was weaker than that at 1st and 3rd weeks.

免疫组化定位分析显示：睾丸组织的神经生长因子蛋白表达于小鼠出生后的各个时期内，1周龄睾丸组织免疫阳性反应主要位于支持细胞，精原细胞也有着色；3周龄睾丸组织的间质细胞、各级生精细胞、支持细胞、管周肌样细胞表达均呈现阳性；5周后的睾丸组织内神经生长因子呈低水平表达，主要表达于间质细胞和生精细胞内。

Results The mortality rate of mice in 80 mg/kg, day cyclophosphamide group was 16.7%, and T level [ at 30th day :( 1.38 ± 0.31 );45th day:( 1.15 ± 0.26 ) ] and T/LH ratio [ at 30th day:(0.163 ± 0.014); 45th day:(0.127 ± 0.023 ) ] were significantly decreased (all P＜0.05) at 30th day after induction;The concentration of MDA [at 15th day:(2.70 ± 0.41);30th day:(2.710.36);45th day:(2.67 ±0.43) ] was maintained at a high level (all P＜0.05) during the 45 days ; Number of Leydig's cells [ at 15th day:(9.65 ± 0.75 ); 30th day:( 14.05 ± 0.67 ); 45th day:(8.49 ± 072)] and layers of spermatogenetic epithelia [ at 15th day:(4.75 ± 0.82);30th day:(3.60 ± 0.49);45th day:(3.74 ± 0.43 ) ] were significantly decreased ( all P ＜ 0.01 ) and stabilized in a low level. The induced model was stable and the mortality rate was acceptable. In the 60 mg/kg, day cyelophosphamide group, the T level and T/LH ratio had no significant change (P ＞ 0.05 ), and the concentration of MDA ,number of Leydig' s cell and layers of spermatogenetic epithelia recovered at 30th day after induction. The induced model was unstable.

结果 剂量每日为80 mg/kg体重小鼠成模后死亡率为16.7%，血清T[30 d：(1.38±0.31)；45 d：(1.15±0.26)]及T/LH比值[30 d：(0.163±0.014)；45 d：(0.127±0.023)]于诱导后第30天出现显著下降(P均＜0.05)，而诱导后睾丸组织内MDA含量[15 d：(2.70±0.41)；30 d(2.71±0.36)；45 d：(2.67±0.43)]维持高水平(P均＜0.05)，生精上皮层次[15 d：(4.75±0.82)；30 d：(3.60±0.49)；45 d：(3.74±0.43)]和间质细胞[15 d：(9.65±0.75)；30 d：(14.05±0.67)；45 d：(8.49±0.72)]均显著减少(P均＜0.01)并稳定于低水平，模型稳定，死亡率适当；每日60mg/kg体重组小鼠血清T及T/LH比值于不同时段并未出现明显变化(P＞0.05)，且睾丸组织内MDA含量、生精上皮层次和间质细胞计数在30 d后有所恢复，模型不稳定；每日100 rag/ks体重组死亡率为30.0%，死亡率过高。

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。

However, on the view of development, we must base ourselves upon our own country whatever it is for fine blanking die or for fine blanking materials and fulfill home made.

但是，从发展的角度来看，无论是精冲机、精冲模具，还是精冲材料都应该立足于国内，尽早实现精冲技术的国产化。

The results showed that (1) COX-2 mRNA and protein existed in the mature male rat testis. COX-2 was localized in spermatocytes by immunohistochemistry.(2) COX-2 also existed in adult man testis. COX-2 protein was positively stained in spermatocytes and Leydig cells.(3) 2 weeks after administration of rofecoxib, the level of testosterone in the whole testis reached its lower values, being only 50% of control values. However, testosterone level recovered during 4 weeks. After such treatment, histologic examination of these testes showed atrophy of the seminiferous tubules and maturation arrest of spermatogenesis.(4) 2 weeks post-EDS, expression of COX-2 decreased significantly (P.005), in comparison with vehicle-treatment control. 4 weeks after treatment, a new generation of fetal like Leydig cells repopulated in the testicular interstitium resulting in COX-2 expression partially recovered. Although the expression of COX-2 mRNA and protein are enhanced at 8th week after using external testosterone, it wasn't significant higher than control group.

实验研究证明：(1)正常成年雄性大鼠睾丸组织中COX-2在mRNA和蛋白质水平均存在表达，免疫组织化学结果显示COX-2定位于曲细精管内的生精细胞；正常成年男性睾丸组织中同样存在COX-2表达，免疫组织化学结果显示COX-2定位于曲细精管内的生精细胞和Leydig细胞；(2)服用特异性COX-2酶抑制剂rofecoxib 2周后，实验组大鼠睾丸组织内睾酮的含量减少，为正常对照组的50％；持续用药4周后睾丸组织内睾酮浓度逐渐恢复至正常水平；COX-2酶活性降低后病理组织切片显示睾丸内曲细精管萎缩，生精紊乱，持续用药4周时影响最明显；(3)注射特异性Leydig细胞杀灭剂EDS 2周后，实验组大鼠睾丸组织内睾酮浓度降至极低水平时，COX-2的蛋白和基因表达水平也显著低于正常空白对照组（P.005）；使用EDS后第4周，睾丸组织中的睾酮浓度逐渐回升，同样组织中COX-2蛋白表达和mRNA表达水平也相应提高接近正常水平；使用EDS后4周开始给予外源性睾酮，6周和8周时COX-2表达水平的绝对值虽有提高，但与正常大鼠空白对照组比较并无显著性差异，说明外源性雄激素刺激睾丸合成COX-2的作用并不明显。

Now the overseers of the workmen were Jahath and Abdias of the sons of Merari, Zacharias and Mosollam of the sons of Caath, who hastened the work: all Levites skilful to play on instruments.

这些工人都勤于操作，监管他们工作的监督是默辣黎族的肋未人雅哈特与敖巴狄雅，和刻哈特族的则加黎雅与默叔蓝；尚有精于乐器的肋未人

We specialise in the design and manufacture meet the customer demand for LCD and LCM, to achieve the "complete customer satisfaction," the policy of product quality requirements.

我们精于设计和制造符合客户需求的LCD及LCM，以达到&客户完全满意&的产品品质政策之要求。

However, as the name（read－only memory）implies, CD disks cannot be written onorchanged in any way.

然而，正如其名字所指出的那样，CD盘不能写，也不能用任何方式改变其内容。

Galvanizes steel pallet is mainly export which suits standard packing of European Union, the North America. galvanizes steel pallet is suitable to heavy rack. Pallet surface can design plate type, corrugated and the gap form, satisfies the different requirements.

镀锌钢托盘多用于出口，替代木托盘，免薰蒸，符合欧盟、北美各国对出口货物包装材料的法令要求；喷涂钢托盘适用于重载上货架之用，托盘表面根据需要制作成平板状、波纹状及间隔形式，满足不同的使用要求。