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排序方式: 共有73条查询结果,搜索用时 23 毫秒
1.
本文探索了重组人生长激素(Recombinanthumangrowthhormone,rehGH)对幼麝鼠生殖系统发育的影响。结果表明,rehGH使试验组麝鼠睾丸间质细胞和精原细胞数量明显增加,曲细精管内的初级精母细胞数量(5675,5850和1050个/标准口径曲细精管,P<001)显著增加;试验组卵巢中生长卵泡数量较多,而且有发育后期的卵泡,对照组卵巢中则没有这种卵泡。  相似文献   
2.
黄鳝精巢显微和超微结构的研究   总被引:8,自引:0,他引:8  
张小雪  董元凯 《水利渔业》1994,(4):9-11,56,F003
通过光镜和透射电镜研究雄鳝和雌雄间体鳝性腺。结果表明:①精巢的发育可分为六个时期;②精子细胞变态过程中,细胞核染色质的变化为细颗粒状→粗颗粒状(小团块)→高电子密度的均质物:③精子分为头部、颈部和尾部,头部为圆形,无顶体;④雌雄间体鳝的精细胞与同期雄鳝的精细胞发育程度基本相同。  相似文献   
3.
Effect of experimentally induced thyroxine overdose on the testis and seminal vesicles was studied in the air-breathing catfish, Clarias gariepinus during the preparatory and the pre-spawning phase. The present study revealed a marked reduction in testosterone level in serum, testis and seminal vesicles (SV). Histological examination showed a considerable reduction in the number of spermatozoa/spermatids in the seminiferous tubular lumen as well as depletion of fluid in the loculi of SV. SDS-PAGE analysis of SV fluid proteins demonstrated a significant decrease in the level of a ~27 kDa protein in thyroxine treated fishes. Evidences are presented here to indicate that thyroid hormone plays a role in regulating testis and SV function in catfish. T.N. Jacob and J.P. Pandey contributed equally  相似文献   
4.
[目的]探讨乌贼墨多糖对环磷酰胺致小鼠睾丸氧化应激损伤的保护作用.[方法]随机将70只成年雄性昆明小鼠分成7组:正常组、模型组、治疗组1、治疗组2、治疗组3、治疗组4和治疗组5,通过对小鼠腹腔注射环磷酰胺进行造模,灌胃乌贼墨多糖作为化疗保护剂,检测小鼠的体重、睾丸和附睾重量、睾丸指数和附睾指数、精子畸形率、睾丸中抗氧化指标,同时观察睾丸组织结构.[结果]乌贼墨多糖能提高小鼠体重和睾丸重量,降低精子畸形率,提高睾丸组织中抗氧化酶SOD和CAT活性,降低MDA含量,修复睾丸病理学损伤.乌贼墨多糖明显缓解环磷酰胺对睾丸的氧化损伤,其最佳灌胃剂量为80 mg/kg.[结论]乌贼墨多糖有可能作为临床上的化疗辅助药物.  相似文献   
5.
用组织学方法对中国美利奴公羊四季睾丸的生精过程研究结果表明,公羊的各级生精细胞数量、精子发生率以及精子日产量等均呈季节性变化,秋季最高,冬春季最低(仅为秋季的60%~70%);繁殖季节与非繁殖季节差异极显着(p<0.001);睾丸中曲细精管直径、生精上皮高度以及生精细胞、内分泌细胞的数密度呈现明显的季节性规律变化。  相似文献   
6.
山羊甘肃棘豆中毒睾丸、附睾的病理学研究   总被引:5,自引:0,他引:5  
山羊甘肃棘豆中毒睾丸、附睾的病理学研究丁伯良,王建辰,薛登民,贾维真,王淑娥(西北农业大学兽医系,杨陵712100)马远莉(陕西省农科院农业测试中心)摘要对6只10月龄西农莎能奶山羊公羊每日按10g/kg剂量单笼饲喂甘肃棘豆粉,4只同龄公羊作对照。1...  相似文献   
7.
河豚的食用安全性及营养价值研究进展   总被引:2,自引:0,他引:2  
阐述了河豚食用安全性,以及国内外对河豚鱼肉、肝脏和精巢营养价值的研究现状,以期为养殖低毒或无毒的河豚、科学地利用河豚资源及开放河豚市场提供参考。  相似文献   
8.

Background

Seminomas in the dog have traditionally been assumed to resemble human spermatocytic seminomas, based on their low malignancy and high occurrence in old individuals. However, recently published studies indicate that canine seminomas can be classified as classical and spermatocytic seminomas in a similar way as in man, and that classical seminomas comprise a substantial proportion of seminomas in the dog. These two factors both contribute to increasing the potential of canine seminoma as a relevant model for human testicular cancer. The aim of the present study was to characterise seminoma in Norwegian dogs using morphology and immunohistochemistry, and determine whether these tumours are comparable with human classical seminoma.

Methods

By applying diagnostic criteria from human pathology, 45 seminomas from the Norwegian Canine Cancer Register were examined histologically with hematoxylin and eosin (HE) and periodic acid-Schiff (PAS) stains. All sections were stained immunohistochemically with antibodies against human placental alkaline phosphatase (PLAP) and the transmembrane receptor c-KIT.

Results

Although two of the seminomas showed immunohistochemical staining characteristics indicative of classical seminoma (PLAP+/c-KIT+), all 45 examined seminomas were morphologically consistent with spermatocytic seminoma.

Conclusions

The value of canine seminoma as a model for SE in man remains unclear. Among the 45 investigated tumours from Norwegian dogs, none were classified as classical seminoma based on morphological criteria consistent with human seminomas. Regional or breed differences in the occurrence of classical seminoma in the dog, as well as the lack of uniform diagnostic criteria, might explain the discrepancy between the findings in the current study and the results presented by other authors.  相似文献   
9.
本研究采用组织病理学和免疫组织化学技术观察了三聚氰胺(Melamine,MA)对雄性小鼠睾丸的毒性作用,以深入揭示三聚氰胺的毒性作用及其机理。将25只28日龄SPF雄性昆明小鼠随机均分为5组,1组为对照组,其他4组为试验组。4个试验组分别按下述不同剂量灌服三聚氰胺:0.6 mg/kg(bw)/d(每日每公斤体重0.6 mg)、3.0 mg/kg(bw)/d、15.0 mg/kg(bw)/d和17.5 mg/kg(bw)/d,用玉米油做溶剂;空白对照组每日灌服等量玉米油。连续灌胃30天后剖检小鼠并取其睾丸组织进行固定、切片和染色,观察睾丸的组织病理变化。同时,采用免疫组织化学方法检测睾丸组织中增殖细胞核抗原(PCNA)的表达量。观察结果表明,与对照组相比,试验组不同剂量浓度的三聚氰胺对小鼠睾丸组织造成不同程度的病理损伤;三聚氰胺也会在一定程度上影响睾丸组织中PCNA的表达。研究结果表明三聚氰胺对于小鼠生殖系统有明显毒性作用。  相似文献   
10.
Assessing the health of the testes in domestic animals is an important aspect of the breeding soundness examination and selection. The aim of the present study was to develop a simple method for scanning and to establish ultrasonographically the gross anatomic structures of the goat testes. Six adult male goats were examined to study the sonographic appearance of normal testes and epididymides using a water bath based ultrasound scanning technique. The ultrasonographic examinations were done using a 5–9 MHz/60 mm (7.5 MHz) linear-array transducer and a B-mode scanner. The ultrasonographic examination was performed in goats after standardizing the procedure on six testes collected from slaughter house. Results showed that in live goats when the probe was placed directly over the scrotum it gave distorted and unclear image. In water bath method the entire scrotum was dipped into a container filled with water and linear probe was used to observe the sonographic features of the testis. Each testis was viewed vertically, resulting in longitudinal image which was frozen, measured and printed through a thermal printer. The results of the ultrasonogram revealed that the testicular parenchyma was homogenous and moderately echogenic throughout. The diameter (mean±se) of the right and left testes was 4.47±0.14 and 4.42±0.07 cm respectively and no significant difference was observed between the testes. The mediastinum testis was a 1.50±0.22 cm wide linear structure of greater echogenicity than the testicular parenchyma when viewed in the transverse plane and nearly circular echogenic “spot” in the midline of the testis when viewed horizontally. The head and tail of the epididymides were easily identified on all the testes, but the epididymal body and ductus deferens were difficult to identify consistently. The tail of the epididymis was easily identified on the distal end of the testis with sonolucent tubules and appeared sonographically as a ‘peaked cap’ upon the testicular parenchyma. The diameter (mean±se) of the tail of right and left epididymis was 2.11±0.18 and 1.92±0.06 cm and no significant difference was observed between epididymides. The vascular pampiniform plexus (1.42±0.18 cm) was easily identified on the proximal end of the testes. The tunics of the testes appeared as a bright echogenic line. Inter-testicular septum appeared between testes as a hyperechoic line. It is concluded that ultrasonography permits a noninvasive evaluation of the internal structure of the scrotum and testes and water bath based sonographic examination may prove to be a valuable simple diagnostic methodology for evaluating physiopathologic conditions of goat testes and can be employed as a routine investigative method during breeding soundness and clinical examination.  相似文献   
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