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81.
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
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Deep-frozen semen from 28 bulls belonging to 6 different A.I. centres was studied after thawing and the ATP content in the spermatozoa was assayed using a bioluminescence technique. The sperm motility was subjectively estimated under a phase contrast microscope and the sperm concentration of each ejaculate was calculated in a haemocytometer. The overall mean ATP content was 16.6 nmoles ATP/spermatozoa x 10(8). There was a significant variation in ATP content between A.I. centres. Significant differences between bulls in ATP content were found as well as a significant correlation between ATP concentration and the number of motile spermatozoa. This may indicate that ATP assessment may be useful as an additional, objective laboratory test. 相似文献
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Eight animals, 3 heifers and 5 primiparous cows, were artificially inseminated by intrauterine deposition of frozen-thawed semen. The insemination dose comprised 20×106 or 200 × 106 spermatozoa, frozen in French mini straws. Four animals were inseminated at fixed time interval (72 or 84 h) after cloprostenol injection. The remaining 4 animals were inseminated in spontaneous oestrus. Slaughter took place 2 or 12 h after insemination. After fixation the oviducts were cut into segments, which were serial-sectioned and stained. Six sections per segment were examined under the microscope for sperm recovery.The number of spermatozoa recovered from the oviducts varied considerably among animals. Recovery was poor (less than 50 spermatozoa) in 4 animals. Recovery was low when insemination took place in induced oestrus and with the lower sperm number (20×106). In animals in which more than 50 spermatozoa were found the distribution varied both between animals and between oviducts within the same animal. Overall, more spermatozoa were found in the lower (UTJ, isthmus and AIJ) than in the upper (ampulla) parts of the oviducts. In 3 out of 4 animals more spermatozoa were recovered from the left than from the right oviduct. Only in 1 animal were the majority of spermatozoa found in the oviduct ipsilateral to the follicle-bearing ovary. 相似文献
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Hiroshi KAGAMI Jun YASUDA Takahiro TAGAMI Mitsuru NAITO Yuko MATSUBARA Takashi HARUMI Takamasa NOGUCHI Yasuhiro YAMAMOTO Taikai TAKAHASHI Junichi MATSUYAMA Hiroyuki KOMATSU Tamao ONO 《Animal Science Journal》2002,73(6):453-456
Effect of the strain combination of the donor and recipient on production efficiency of W‐bearing sperm in mixed‐sex chimeric testes was analyzed. The combinations of the donors and recipients were White Leghorn (WL) and Rhode Island Red (RIR), and vice versa. Generated mixed‐sex chimeras that had the male phenotype at sexual maturity were classified into four groups: (1) a female WL donor and a male RIR recipient; (2) a male WL donor and a female RIR recipient; (3) a female RIR donor and a male WL recipient; (4) a male RIR donor and a female WL recipient. The mean number of W‐bearing sperm detected by in situ hybridization among 10 000 sperm observed were 147, 165, 30 and 45 in groups 1, 2, 3 and 4, respectively. The numbers in groups 1 and 2 were both significantly higher than those of groups 3 and 4 (P < 0.05). The combination of a WL donor and a RIR recipient produced W‐bearing sperm more efficiently than the reverse combination. 相似文献
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通过胞质内精子注射法介导转基因已经成为生产转基因动物的一种有效手段。然而传统的ICSI介导法用冻融精子或Triton X-100处理的精子作为携带外源DNA的载体,经胚胎移植后生产转基因后代的效率很低,主要原因为这些处理方式在提高转染效率的同时对精子染色体造成了较大程度的损伤。最近研究者们提出了一种使用高浓度碱液对精子进行简单的预处理,高效地生产转基因后代的方法。这些精子完全失去了质膜与顶体,但仍保留有核的完整性,并且可以高效的将外源基因插入宿主基因组,比传统的精子处理方法获得了更理想的转基因动物的生产效率。 相似文献
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利用透射电镜(TEM)技术观察了魁蚶精子发生过程的超微结构变化。结果表明:魁蚶精子发生经历了精原细胞、初级精母细胞、次级精母细胞、精子细胞和精子形成等过程,在精子形成中的主要细胞学事件包括顶体的发育、核形态变化及尾部的形成等。此过程中,前顶体颗粒聚集、融合,形成顶体囊,然后发育为圆锥形顶体;核的形态由圆形或卵圆形变为鼓形,核内染色质由团块状到颗粒状,再到高电子密度均质;线粒体聚集、融合、体积变大,迁移至核的后端,参与精子中段的形成。成熟精子由头部、中段及尾部组成,头部由顶体及核构成,中段由5个线粒体围绕远端中心粒组成,尾部为细长的鞭毛。研究亮点:魁蚶为我国重要的海产经济贝类之一,目前对其精子发生过程的超微结构未见研究报道。利用透射电镜技术观察了魁蚶精子发生过程中精子顶体的形成、核的形态建成等主要细胞学事件,探明了魁蚶精子属原生型,顶体物质的合成始于初级精母细胞时期,细胞核在精子发生过程中形态变化不大等问题,为蚶科精子发生机制的深入研究提供了参考。 相似文献