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11.
Testicular seminoma with elevated serum human chorionic gonadotropin level (hCG-positive seminoma) is regarded as more malignant than marker-negative seminoma, although Its prognosis is still unclear. To clarify the malignant potential of seminoma with hCG production, the serum levels of the beta subunit of hCG (β-hCG) and lactic acid dehydrogenase (LDH) were examined in 35 and 40 patients, respectively, and the Immunohistochemical expression of β-hCG examined in 45 tumors. The elevation of the LDH serum level correlated to the Invasive status, metestatic status and poor outcome, while that of the serum β-hCG level correlated only to the metastatic status. Immunohistochemical expression of β-hCG was observed in syncytiotrophoblastic giant cells in 11 tumors and a few mononuclear seminoma cells In 36 tumors. Expression was not associated with the malignancy potential, except where the expression In mononuclear cells Inversely correlated to the invasive status. These results suggest that most seminomas produce a slight amount of hCG; that an elevated hCG serum level Indicates the pressnce of metastatic tumors and mainly reflects an increase in tumor volume but not in cellular malignancy potential; and that the LDH serum level, rather than hCG, is more useful as a prognostic indicator for patients with seminoma.  相似文献   
12.
热休克蛋白70-2基因在大鼠隐睾中的表达及意义   总被引:4,自引:0,他引:4  
目的 :探讨Hsp70 2基因表达在大鼠隐睾生精细胞中的作用。方法 :采用 2 2日龄Sprague Dawley雄性大鼠复制单侧隐睾模型 ,运用免疫组织化学SP法检测Hsp70 2和cdc2 基因在大鼠隐睾侧和对侧睾丸组织中的表达 ;运用生物素 dUTP 酶标亲和素测定法检测睾丸生精细胞凋亡。结果 :术后第 7d ,与对侧睾丸相比 ,隐睾侧Hsp70 2表达下降显著 (P <0 .0 1) ,cdc2 表达无显著性变化 (P >0 .0 5 ) ,生精细胞凋亡显著性增加 (P <0 .0 1)。术后第 14d ,隐睾侧生精细胞少见 ,Hsp70 2和cdc2 表达呈阴性。结论 :隐睾可以引起生精细胞发育停止和凋亡增加 ,这可能与Hsp70 2表达下降或不表达有关  相似文献   
13.
Marker enzymes of Sertoli and germ cells were estimated to study the mechanism of action of antispermatogenic compound CDRI 84/35 in adult male rat testis. Animals were killed after 22, 41, and 64 days of treatment with antispermatogenic dose of CDRI 84/35 in order to evaluate the effect of the compound on spermatid, spermatocyte, and spermatogonial stages, respectively. Studies were also extended to a recovery period of 90 days. Results indicate a direction action of the compound on germ cells, with no apparent effect on Sertoli cells. Studies also show a massive depletion of postmeiotic germ cells after the treatment, with some damage to premeiotic germ cells as well. Reversibility of the compound was partial, with the marker enzymes of pre- and postmeiotic germ cells not being restored to control levels after withdrawal of treatment.  相似文献   
14.
Objective: To study the changes in 5α-reductase type Ⅱactivity in sex glands of pubertal and adult male rats with diabetes. Methods: Pubertal (40 days old) and adult (90 days old) male Wistar rats were used, 30 animals in each group. Each group was randomly divided into 3 subgroups: the control (C), the diabetic (D) and the diabetic with insulin replacement (ID). The activity of 5α-reductase type Ⅱ was determined with thin layer chromatography in the epididymis, prostate and testis. Results: (1) In all the sex glands of pubertal rats, the enzyme activity was significantly lower in group D than in groups C and ID. (2) In all the sex glands of adult rats, there was no significant difference in the activity. Conclusion: In male rats, the activity of 5αa-reductase type Ⅱ in sex glands is more vulnerable to diabetes in pubertal rats than in adult rats.  相似文献   
15.
目的:探讨饮酒大鼠睾丸总抗氧化能力(T-AOC)、一氧化氮(NO)含量和一氧化氮合酶(NOS)活性的变化与生殖细胞凋亡的关系。方法:20只成年健康SD雄性大鼠随机均分为对照组和实验组,实验组和对照组分别用50%的乙醇溶液和蒸馏水按10 m l/kg每晚灌胃1次连续26 d(两个生精周期)后,用硝酸还原酶法测定睾丸组织中NO含量;用化学比色法测定其T-AOC和NOS活性;原位缺口末端标记(TUNEL)法检测生殖细胞凋亡指数(AI)的变化。结果:与对照组相比,实验组生殖细胞AI增加(P<0.01);睾丸组织T-AOC极显著下降(P<0.01),而NO含量明显上升(P<0.01)、NOS活性显著增强(P<0.01)。结论:大量饮酒能诱导生殖细胞凋亡增加,NOS活性增强导致NO的过量产生及T-AOC的显著下降是其重要原因。  相似文献   
16.
本实验以合并3-氯丙二醇和2,3-氧丙醇(5+75mg/kg/d×2)给大鼠9个疗程,停药120天,共历程210天。观察其睾丸及附睾头、精囊某些生化成份的影响,其结果表明实验组之糖蛋白、RNA、DNA,含量有不同变化,停药120天未能完全恢复。停药120天后,乳酸脱氢酶活性及其同功酶酶谱的分析表明,能量的供能未能恢复到对照组的水平。从酶谱来看,药物所致的供能方式受损伤,因器官不同而有不同,并讨论了药物所致的不育,可能与能量供给有关。  相似文献   
17.
缺锌对大鼠力竭性游泳前后睾酮和锌水平变化的影响   总被引:5,自引:1,他引:4  
本实验动态观察了缺锌和缺锌后补锌对大鼠力竭性游泳前后辜丸和血清睾酮、锌水平以及游泳能力的影响。结果显示:缺锌造成大鼠游泳能力大大降低,补锌后明显增加。不论安静时还是力竭性游泳后12小时内,缺锌大鼠的血清和辜丸锌含量均显著低于对照和补锌大鼠。与对照和补锌大鼠相比,缺锌大鼠的血清和睾丸酮含量,安静时均较低,力竭性游泳后也呈现不同程度的降低。缺锌还造成大鼠辜丸重量的明显下降。结果表明,锌营养不良将损害运动能力。  相似文献   
18.
Metastatic carcinoma to the testis is very rare. Metastasis of prostate adenocarcinoma to testis was detected incidentally after bilateral orchiectomy for hormonal management of metastatic prostate carcinoma. The metastatic lesion was not identified in physical examination or in macroscopic dissection of the testis after surgery. Microscopy revealed an adenocarcinoma which, given the history of the patient and a positive immunohistochemical stain for PSA, was identified as metastatic prostatic adenocarcinoma.  相似文献   
19.
为了探讨彩色多普勒血流显像技术显示正常人睾丸内血流的可行性,并探讨睾丸的血流动力学特征,我们对20名正常人双侧睾丸进行了彩色多普勒检查。结果显示,彩色多普勒能显示所有睾丸的包膜动脉、向心动脉。正常睾丸的包膜动脉和向心动脉收缩期峰值血流速度的均值分别为9.00cm/s和7.42cm/s;舒张末期血流速度均值分别为3.50cm/s和3.38cm/3,本文对睾丸彩色血流显像和多普勒频谱特点也作了讨论。  相似文献   
20.
HtrA2 is up-regulated in the rat testis after experimental cryptorchidism   总被引:3,自引:0,他引:3  
AIM: The aim of the present study was to elucidate the role of high temperature requirement A2 (HtrA2) in germ cell loss in the heat-stressed testis. METHODS: We examined the expression of HtrA2, caspase-9 activity and proteolytic activity of HtrA2 in the rat testis, and their in vivo responses to experimental cryptorchid treatment. RESULTS: Northern analysis revealed the expression of HtrA2 mRNA peaked at days 1 and 7 after cryptorchid treatment. While expression of HtrA2 mRNA was seen in the spermatogonium, spermatocytes and some spermatids in normal adult rat testis, experimental cryptorchidism treatment resulted in a marked increase in its signal intensity in spermatocytes and some spermatids, and the layers of spermatogonium and early primary spermatocytes became negative at days 1 and 7 after the treatment. However, the spermatogonium, Sertoli cells and interstitial cells appeared to have strong intensities at days 14, 28 and 56 after the treatment. Western analysis revealed the expression of HtrA2 protein peaked at day 2 coinciding with the increase of positive spermatogonium, the appearance of protein-positive interstitial cells, and day 28 coinciding with the reappearance of protein-positive interstitial cells. Caspase-9 activity peaked at day 2 and HtrA2 proteolytic activity peaked at day 28. Consequently, the first peak of HtrA2 mRNA expression was followed by the peak of caspase-9 activity and the second peak was followed by the peak of proteolytic activity; however, the second peak of mRNA expression had considerable chronological difference from that of the protein. CONCLUSION: These findings suggest the probabilities that the heat stress results in germ cell death by a caspase-independent manner with the elevation of HtrA2 proteolytic activity, as well as a caspase-dependent manner with the elevation of caspase-9 activity.  相似文献   
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