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11.
Histologically verified tumours submitted to the Norwegian Canine Cancer Register from 1990 to 1998 were studied (n=14,401). The proportion of testicular tumours (n=345) was 2.4%, and the breakdown of histological tumour diagnoses is presented. The frequency of the most common histopathological types was 33% interstitial (Leydig), 26.4% Sertoli and 33.9% seminomas/germ cell tumours. The average age at diagnosis was 10 years, but was significantly lower for Sertoli cell tumours (8.6 years) than for the other tumour types. Following a histopathological re-evaluation, 22.5% of the original tumor diagnoses were modified. Proportional morbidity ratios were calculated and individuals from the breeds Shetland sheepdog and Collie were five times more likely to have testicular tumours than the overall average for the registry. Breed differences in the distribution of histopathologic types were observed. Shetland sheepdog and Collie were most commonly diagnosed with Sertoli cell tumours, while all tumours from Norwegian elkhound in this material were seminomas.  相似文献   
12.
【目的】 试验旨在从代谢组学角度探究关中奶山羊睾丸发育代谢机制。【方法】 选择1月龄断奶雄性关中奶山羊和24月龄体成熟的雄性关中奶山羊各6只,采集睾丸组织,使用液相色谱-质谱(LC-MS)技术对睾丸组织进行化学检测,通过多维和单维分析相结合的方式对两组不同代谢物进行化学检测、对比与鉴别,通过富集差异代谢物分析筛选关中奶山羊发育代谢中的潜在关键通路。【结果】 在1和24月龄关中奶山羊睾丸组织中共筛选出334个差异代谢物,其中显著上调137个,显著下调197个。对前36个差异代谢物进行比较鉴定发现,分别为脂质和类脂质分子、有机酸及其衍生物、未分类化合物和苯丙烷和聚酮化合物四大类。经相关性分析发现,在1和24月龄关中奶山羊睾丸发育过程中,脂质和类脂质分子与甘油磷脂呈最大正相关,羧基及其衍生物与甘油磷脂呈最大负相关。对不同的代谢物进行富集分析,筛选出7条潜在的重要代谢通路,分别为肿瘤中的胆碱代谢、精氨酸和脯氨酸代谢、肿瘤中的中心碳代谢、铁死亡、谷胱甘肽代谢、氨酰-tRNA生物组成以及牛磺酸和亚牛磺酸代谢。【结论】 本试验从代谢组学角度揭示了1和24月龄关中奶山羊睾丸的差异代谢物及代谢机制,为今后哺乳动物睾丸的发育研究奠定了基础。  相似文献   
13.
性别决定过程是双潜能胚胎发育成睾丸或卵巢的过程.通过小鼠基因敲除试验以及在遗传水平分析性反转病人证明该过程是由多个基因调控的.论文综述了睾丸发育通路中信号分子成纤维细胞生长因子9(FGF9)在性腺分化中的作用.FGF9基因参与调节早期睾丸发育的3个重要事件,为调节性腺体腔上皮细胞增殖,促进Sertoli前体细胞形成,调节中肾细胞迁移,影响睾丸索的形成,FGF9诱导FGFR2在核内定位,并维持Sox9的表达.  相似文献   
14.
In fish, sex steroids initiate and/or accelerate the maturation of the brain-pituitary-gonad axis. In order to obtain information on the steroid milieu during the pubertal development of male African catfish, we have monitored the conversion of [3H]-pregnenolone and [3H]-androstenedione by testis and [3H]-pregnenolone by interrenal tissue fragmentsin vitro. Pubertal development occurs between two and six months of age. Testicular development proceeds through four main stages that are characterised histologically by the presence of spermatogonia (stage I), spermatogonia and spermatocytes (stage II), spermatogonia, spermatocytes and spermatids (stage III), and all germ cells including spermatozoa (stage IV). 11β-Hydroxyandrostenedione and cortisol were the main products of testes and interrenal tissue, respectively, in all stages of the pubertal development; a change in the steroidogenic pattern was not observed during this period. The interrenal tissue displayed no significant conversion of [3H]-pregnenolone to 11-oxygenated androgens. Blood plasma was analyzed for the presence of five androgens; testosterone, 11β-hydroxytestosterone, 11β-hydroxyandrostenedione, androstenetrione, and 11-ketotestosterone. 11-Ketotestosterone was the quantitatively dominating androgen in the circulation at all stages of development, which was more pronounced in stages III and IV. The obvious differences between thein vitro andin vivo results, namely 11β-hydroxyandrostenedione being the main testicular productvs. 11-ketotestosterone dominating in the blood, may indicate that 11β-hydroxyandrostenedione is converted to 11-ketotestosterone at extratesticular sites.  相似文献   
15.
Ovaries and testes from the Russian sturgeon at different stages of sexual maturity were incubated with ;sup3;H-androstenedione or 3H-pregnenolone. The major metabolites of androstenedione in both sexes were testosterone and 5- and 5ß-androstanediols, but no evidence was found for the gonadal production of 11-oxygenated androgens. Pregnenolone was converted to 17-hydroxyprogesterone, androstenedione and testosterone together with reduced metabolites. 11-Oxygenated androgens were found in female serum by gas chromatography-mass spectrometry (GC-MS), in serum of both sexes by radioimmunoassay (RIA), and was detectable by RIA in interrenal but not gonadal tissue. The results suggest that sturgeon may differ from teleosts in that 11-oxygenation may take place in extragonadal tissues.  相似文献   
16.
Growth hormone (GH) and reproduction: a review   总被引:5,自引:0,他引:5  
Interaction between growth and reproduction occurs in many vertebrates and is particularly obvious at certain stages of the life cycle in fish. Endocrine interactions between the gonadotropic axis and the somatotropic axis are described, the potential role of GH being emphasised. A comparative analysis of these phenomena in mammals, amphibians and fish, suggests a specific role of GH in the physiology of puberty, gametogenesis and fertility. It also shows the original contribution made by studies on the fish model in this field of investigations.  相似文献   
17.
研究发现除了内分泌调控外,睾丸神经对睾丸的发育、雄激素的分泌以及精子的发生也发挥重要的调节作用,与睾丸的内分泌调节功能相比较人们对植物性神经在睾丸生理活动调节方面的认识还很少。论文从睾丸的植物性神经分布、精索神经对睾丸发育和睾丸生理功能的影响以及睾丸不同发育时期胆碱能受体和肾上腺素能受体的分布、神经递质NE和Ach对睾丸发育和功能的影响等方面做了详细综述,并对今后的研究方向和研究意义做了展望。  相似文献   
18.
Testes from spermiating goldfish were incubated with [3H]17-hydroxyprogesterone. The major products in the unconjugated fraction were identified as androstenedione, androstenetrione, 11-β-hydroxyandrostenedione, 11-ketotestosterone, 17,20α-dihydroxy-4-pregnen-3-one (17,20αP) and 11-deoxycortisol. Testosterone was present predominantly in the glucuronide fraction, but yields were low (1–3%). The major components of the sulfate fraction were 17,20αP and 11-deoxycortisol. The identification of cortisone in low yield (< 2.5010) in both the free and sulfate fractions is the first report of corticosteroid biosynthesis by a teleost testis. The high yields of 17,20αP and 11-deoxycortisol and their sulphates suggests that their possible role in spermiation of the goldfish should be further investigated.  相似文献   
19.
目的探讨3-甲基-4-硝基酚(PNMC)对雄性小鼠的生殖毒性作用。方法 20只小鼠随机分成阴性对照组和PNMC组(分0.9、9和90mg/kg·bw组),经口灌胃染毒30天,观察睾丸和精子的形态变化。结果染毒组小鼠各剂量睾丸生精细胞发生坏死,曲细精管腔内出现细胞团,精子细胞分化异常,形成均质红染颗粒,睾丸曲细精管生精上皮/直径比值在90mg/kg组明显高于对照组;染毒组小鼠精子畸形率明显高于对照组(P<0.05),并且随着染毒浓度的增加,畸形率有增加的趋势。结论 3-甲基-4-硝基酚不仅可以引起生精细胞坏死和抑制精子形成,还可以诱导精子畸变,从而对生殖系统造成损伤。  相似文献   
20.
This study was conducted to determine the effects of hormone treatment on testis structure in Barbus sharpeyi, as well as the morphology of sperm examined by scanning electronic microscopy (SEM). Male B. sharpeyi were divided into three groups (three fish per group) and injected with luteinizing hormone – releasing hormone analogue (LHRH–A2) or carp pituitary extract (CPE). The first and second groups were treated with 10 μg kg?1 LHRH–A2 and metoclopramide (MET), and their testis were sampled pre‐ and Poststripping respectively. The third group received 2 mg kg?1 CPE and were killed pre‐stripping. Based on the histological results obtained, the testicular connective tissue of the lumen was thicker, and seminal vesicles were of a lower volume, in fish injected with CPE in comparison to the other groups. After treatment with LHRH–A2 and MET, not all spermatozoa within the testis were ejaculated, and only a small amount of sperm was obtained by abdominal stripping. The highest and lowest diameters of connective tissue within lobules were observed in fish receiving CPE and LHRH–A2 treatments respectively. There was a significant difference (P < 0.05) in lobule space between the fish injected with the CPE and the fish injected with the LHRH–A2 and MET. The SEM results revealed that the spermatozoa of B. sharpeyi were composed of a spherical to elliptical head, a cylindrical midpiece, and a lengthy flagellum. In conclusion, it was found that injection with LHRH–A2 and MET improved the spermatogenic process in comparison to injection with CPE.  相似文献   
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