共查询到20条相似文献,搜索用时 46 毫秒
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胰高血糖素、血管紧张素、糖皮质激素均可诱导鼠、兔肝肾等器官金属硫蛋白(metalothionein,MT)的合成。兔在怀孕早期MT对从母体转移Zn至兔胎儿起调节作用。孕酮是家猫妊娠过程中的主要激素,它是否对肝MT有诱导作用,研究这一课题有助于阐明孕激... 相似文献
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力竭性游泳对大鼠睾丸金属结合蛋白的诱导及其与睾酮和锌… 总被引:6,自引:0,他引:6
本研究通过观察大鼠力竭性游泳后睾丸金属结合蛋白(TMBP)、睾酮和锌含量的动态变化,探讨TMBP的被诱导性、诱导特点以及与睾酮合成和锌代谢的关系。结果显示:大鼠力竭性游泳后,TMBP呈一过性升高,峰值在游泳后6h处,达安静时4 16倍;游后12h已降回原有水平。这表明TMBP可被力竭性游泳所诱导,并减期不至6h。TMBP诱导性的发现对认识TMBP的功能具有重要的意义。大鼠睾丸酮在力竭性游泳后即刻急 相似文献
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金属硫蛋白为一类广泛地存在于生物界的低分子量、富含半胱氨酸的金属结合蛋白,尤其对Cd,Zn,Cu和Au,Ag等有较强的亲和力。它是一种诱导合成的蛋白质,在体内能被金属和糖皮质激素等所诱导。它具有广泛的生物学功能,主要是参与微量元素的储存、运输和代谢,拮抗电离辐射,清除羟基自由基和重金属解毒等多种作用。某些微量元素缺乏症等疾病也与它有一定关系。今后在某些疾病的治疗、环保中清除有毒金属以及采矿、富集贵重金属等方面有着广泛的应用前景。 相似文献
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金属硫蛋白的生物学特性及生理作用 总被引:12,自引:0,他引:12
金属硫蛋白的生物学特性及生理作用朱赓伯(苏州医学院生化教研室,苏州215007)关键词金属硫蛋白金属硫蛋白又名金属硫组氨酸甲基内盐(metallothioneins,MT)。三十年前美国哈佛大学的B.L.Vallee首次在马的肾脏中发现Cd-MT和Z... 相似文献
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镱和铕诱导金属硫蛋白生成的初步研究 总被引:7,自引:0,他引:7
本文研究了不同剂量的稀土元素镱和铕,通过皮下注射对兔肝中金属硫蛋白生成的影响。用Sephadex G50柱对兔肝提取液进行分离,收集的组分用紫外分光光度法、原子吸收光谱法和ELISA法进行分析。实验结果表明,低剂量(1-3ppm)的镱和铕不能明显地诱导兔肝内金属硫蛋白的合成,而高剂量(10-40ppm)的镱和铕可以诱导兔肝金属硫蛋白合成。 相似文献
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The female genital system of the oviparous peripatopsid Ooperipatellus decoratus consists of an ovary, oviducts equipped with receptacula seminis and additional pouches, uteri, and a vagina. It is examined using transmission and scanning electron microscopy. The ovary is made up of paired ovarian tubes united anteriorly and posteriorly and differentiated into a sterile dorsal part and a fertile ventral part with exogenous oocytes. Fertilization presumably occurs in the oviducts once the oocytes pass the receptaculum seminis. Although the receptacula seminis have been reported to occur in juvenile O. decoratus females only, the present study reveals that they are present in adult females as well. Their wall consists of a cuboidal epithelium covered with a thin collagen-muscle layer. The additional pouches are projections of the oviducts facing the receptacula seminis. They are distally closed to the haemocoel by a flattened epithelium and lack external muscle cells. A thin collagen layer is only found proximally. The uteri are characterized by a columnar epithelium with folded cell membranes allowing extension of the uteri, thus facilitating the passage of the large uterine eggs towards the vagina. Another dominating feature of the uteri is a distally increasing secretory production, which probably contributes to chorion development. Cilia occurring along the entire length of the uteri are considered to assist in the transport of eggs towards the vagina. 相似文献
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对3只川金丝猴(Rhinopithecus roxellanae)的雌性生殖器官进行了观察。结果表明,卵巢通常呈椭圆形,两端稍尖,长1.0~1.8cm,宽0.4、0.6cm,厚0.2~0.4cm。有一个体呈一端大、一端小,中间缩细类似亚铃的形状。输卵管两侧均有系膜固定,输卵管上系膜仅0.1~0.2cm宽。子宫略呈长简形,子宫底正中沟不明显,子宫颈管较长,子宫轴与阴道轴在一直线上,子宫颈阴道部明显突出,前唇尤为明显,而阴道后穹比前穹深得多。阴道下半部前壁处皱襞密而高,形成三角形隆起,尖端向尿道外口:阴道前庭内前庭球明显,长约0.5cm,宽约0.2cm,位于尿道外口两侧的椭圆形窝内。 相似文献
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记述了柄天牛属8个种(亚种)的雌性生殖器,比较研究了该属雌性生殖器的结构特点.结果表明:柄天牛属雌性生殖器在骨杆形状、受精囊管长短等方面存在不同程度的差异;通过雌性生殖器特征对比,黄颈柄天牛、暗胸柄天牛、红腹柄天牛三者虽然存在一定差异,是否应作为同一种依据不足,故仍保留亚种地位. 相似文献
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Bell K 《Medical anthropology quarterly》2005,19(2):125-148
This article explores dominant discourses surrounding male and female genital cutting. Over a similar period of time, these genital operations have separately been subjected to scrutiny and criticism. However, although critiques of female circumcision have been widely taken up, general public opinion toward male circumcision remains indifferent. This difference cannot merely be explained by the natural attributes and effects of these practices. Rather, attitudes toward genital cutting reflect historically and culturally specific understandings of the human body. In particular, I suggest that certain problematic understandings of male and female sexuality are deeply implicated in the dominant Western discourses on genital surgery. 相似文献
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Surgical removal of the corpus allatum or neurosecretory cells of the brain results in a marked reduction in protein accumulation in the transparent accessory reproductive gland (TARG) of the male. Topical application of C18 juvenile hormone stimulates a dose-dependent accumulation of protein in allatectomized males. These results suggest that a direct or indirect stimulation by the neuroendocrine system is normally required for TARG protein synthesis. 相似文献
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The morphology of the genital apparatus of two batrachoid species, Opsanus tau and Porichthys notatus , was studied. The anatomical organization of the female reproductive apparatus is similar in both species but differences are observed in the rhythm of gametogenesis with individual oocyte production asynchronous in O. tau and group synchronous in P. notatus. The male reproductive apparatus is similarly organized in the two species, with both showing enlongated testes with an efferent duct system, two main testicular ducts, a common sperm duct, and a pair of multi-channel accessory structures. The sperm transport system consisting of the efferent duct system, main testicular ducts, and sperm duct is more developed in P. notatus and only in this species does it secrete sialoglycoproteins. Male accessory organs also secrete sialoglycoprotein in both species, but they appear more developed in O. tau. Intraspecific variability in development of accessory structures and mucin secretion was also observed between the two male morphs of P. notatus. Type I males, which build nests and perform parental care to eggs and fry, have larger accessory organs and more abundant secretion than type II males, which adopt opportunistic spawning tactics. The possible role played by mucins as components of the seminal fluid, in both species, and their inter-and intraspecific variability are discussed in the light of the reproductive biology and the presence of alternative male mating tactics. 相似文献
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The spermatheca and the accessory glands of the collembolan Orchesella villosa are described for the first time. Both organs exhibit ultrastructural differences, according to the time of the intermolt in which the specimens were observed. A thick cuticular layer lines the epithelial cells of the accessory glands. In the reproductive phase, they are involved in secretory activity; a moderately dense secretion found in the apical cell region opens into the gland lumen. Cells with an extracellular cistern are intermingled with the secretory cells. These cells could be involved in fluid secretion, with the secretory product opening into the cistern which is filled with an electron-transparent material. After the reproductive phase, the gland lumen becomes filled with a dense secretion. The accessory gland secretion may play a protective role towards the eggs. The spermatheca is located between the accessory glands; its epithelium is lined by a thin cuticle forming spine-like projections into the lumen and consists of cells provided with an extracellular cistern. Secretory cells, similar to those seen in the accessory glands, are missing. Cells with a cistern could be involved in the production of a fluid secretion determining sperm unrolling and sperm motility. 相似文献