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1.
研究了油松花粉对雄性幼年小白鼠睾丸发育及精子生成的影响.并与睾酮组和正常对照组进行了比较.结果表明:油松花粉具有类似睾酮的作用,可促进睾丸的发育及精子的生成,油松花粉作为营养保健品开发,儿童不宜服用。  相似文献   
2.
性成熟黄颡鱼精巢的年周期变化:Ⅰ.生精部的周年 …   总被引:7,自引:0,他引:7  
黄颡鱼的精巢从外形上分为上、下两段。上段为生精部,下段为贮精囊。性成熟黄颡鱼精巢的生精部为小叶型结构,其周年变化经历如下过程:Ⅲ期-Ⅳ期-Ⅴ期-Ⅵ期-Ⅲ期。4上月下旬开始生精活动的启动。  相似文献   
3.
报道了白蜡虫雄虫的生殖系统的构造及其发育情况.  相似文献   
4.
镉对鹌鹑睾丸组织的毒性研究   总被引:1,自引:0,他引:1  
为探讨镉对睾丸组织的毒性及其作用机制,用氯化镉灌胃法研究镉离子对雄性鹌鹑(Coturnix coturnixjaponica)睾丸组织结构、睾酮含量、体重、睾丸系数、睾丸脂质过氧化物(MDA)值、血清乳酸脱氢酶(LDH)活性及睾丸中抗氧化酶活性的影响.结果显示染镉组鹌鹑的上述各指标与对照组相比均有显著性差异,表明镉对鹌鹑睾丸有明显毒性作用,脂质过氧化作用及其所致的组织损伤和出血性炎症可能是镉对睾丸损害的重要病理过程.  相似文献   
5.
Methylene blue (MB) is a typical photosensitizing agent and a DNA hybridization indicator, but its modes of interaction with the DNA molecules are not clearly described, particularly in relation to its electrochemical oxidation signals. To probe the DNA‐MB interactions we have used chromosomal salmon testes and supercoiled plasmid sc pUC19 DNA immobilized on home‐made screen‐printed electrodes (SPEs) and a wide range of MB concentrations, from nano‐ to micromolar. The applicability of the home‐made screen‐printed electrodes used for the DNA‐MB studies were tested using standard calf thymus DNA. Two MB oxidation peak signals: MB(I) at ca. ?0.18 V and MB(II) at 0 V vs. Ag/AgCl were detected within ±10–15% standard deviation, signals different from adsorbed MB signal (?0.25 V, pH 4.7). The MB(I) signal, seen when both DNAs were used, showed two plateaus, one at nano‐ and another at micromolar MB concentrations; these were accompanied by the changes in the oxidation signal at 0.98 V, usually attributed to guanine oxidation. In contrast, the MB(II) signal was only seen for salmon testes DNA, indicating various modes of MB interactions with chromosomal and plasmid DNA. In the presence of MB, the guanine related signal (G) at 0.98 V has been amplified significantly (10×), allowing for the identification of the DNAs at low DNA concentrations, the feature particularly useful in the plasmid sc pUC19 detection. The use of another DNA intercalator, riboflavin (RF), aided in the identification of the relation between MB(I), MB(II) and G oxidation signals.  相似文献   
6.
Transgenic animal technology is a powerful tool for researching bioscience, biomedicine, bioreactor, and agriculture. There are various ways to produce transgenic animals. The most common ways currently available are pronuclear microinjection and nuclear transfer techniques. However, these methods usually result in low efficiency, causing mosaic (in pronuclear microinjection), or developmental abnormalities (in nuclear transfer). In 1994, Brinster and his colleagues reported an original method to transfer spermatogonial stem cells from donor to recipient mice. The donor spermatogonia were able to form spermatozoa in recipient testes, and to produce progeny carrying the donor's genetic characters. Since then, a series of novel methods were invented by using spermatogonia transplantation. These new methods facilitate the research and application of spermatogonia. Some of these methods, when combining with genetic modification methods, will form a novel methodology for creating transgenic animals. The present paper reviews the achievements of research on spermatogonia transplantation related to creating transgenic animal. Such as, transplantation techniques, cryopreservation of spermatogonia, preparation of recipients, long-term proliferation of spermatogonia in culture, genetic modification of spermatogonia, and characterization of germ line transmission of the modified gene, etc. Furthermore the methodologies for creating transgenic animals by using spermatogonia transplantation were described. Based on the difference between donors and recipients used, the methodology is categorized into two groups: allogeneic transplantation, and autologous transplantation. Although progress in this research area has been swift, potential difficulties remain to be overcome in each approach. The advantages and existing problems in the methodology are discussed.  相似文献   
7.
树和许多温带野生哺乳动物一样,属于季节性繁殖的动物。昆明地区的树其生殖季节在2至8月初,8月中至次年1月为非繁殖期。成年树的睾丸、卵巢和生殖管道的形态及重量有明显的季节性变化。雌性和雄性生殖系统的发育基本同步。  相似文献   
8.
鸣禽栗鹀性腺季节性差异的研究   总被引:3,自引:0,他引:3  
利用H-E染色方法,IBAS图像分析仪分析及微机处理技术对鸣禽栗巫鸟春秋季的性腺进行了形态学观察和比较,结果发现:鸣禽性腺在重量、体积、精细管和卵泡的最大平均直径以及内部结构组成上均具有明显的季节性差异.这些结果为鸟类性腺的季节性变化提供了基础资料,并为进一步研究激素对鸟类发声学习的影响提供了形态学依据.  相似文献   
9.
刺五加对小鼠睾丸作用的初步研究   总被引:2,自引:0,他引:2  
昆明种健康成年雄性小鼠20只,随机分为两组:给药组和对照组。分别采取腹腔注射刺五加注射液和等量生理盐水30天。取睾丸做常规石蜡切片,组织学观察;并用体视学方法测量睾丸曲细精管直径。结果显示:刺五加使睾丸重量增加了21.7%,曲细精管直径增加了20.5%,并且光镜下生精细胞的层数及精子的数量有所增加。推测刺五加可能有促进精子发生的作用。  相似文献   
10.
对鳜精巢的组织学结构和超微结构进行观察.鳜精巢呈叶型结构,由精原细胞、初级精母细胞、次级精母细胞、精细胞、成熟精子等生殖细胞和支持细胞、间质细胞、边界细胞、类肌细胞、成纤维细胞、内皮细胞等非生殖细胞组成.鳜精子形成过程,精细胞大致经历了鞭毛发生,核质凝缩及核位置的改变,线粒体迁移等过程.鳜成熟精子无顶体结构,头短而圆,主要为核占据,核凹窝发达,尾细长,具侧鳍,尾部轴丝为“9 2”结构.  相似文献   
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