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1.
对生殖期间鳜脑垂体的超微结构进行观察.脑垂体由神经垂体和腺垂体两部分组成.神经垂体组织中存在2种类型的脑垂体细胞,并可以区分A1、A2和B 3种类型的神经分泌纤维,其终端轴突中具有不同直径和形态的分泌颗粒;B型纤维轴突中含有许多透明小囊泡.腺垂体由前外侧部、中外侧部和中间部构成,分布催乳激素分泌细胞、促肾上腺激素分泌细胞、生长激素分泌细胞、促甲状腺素分泌细胞、促性腺激素分泌细胞、促黑色素激素分泌细胞、PAS-高碘酸-雪夫反应细胞和一种非分泌细胞(星状细胞)类型.本文并讨论了繁殖季节排卵前后期鳜脑垂体的超微结构特点.  相似文献   

2.
 应用透射电镜技术观察不同时期的性成熟赤点石斑鱼(Epinephelus akaara)脑垂体的超微结构。结果表明,性成熟赤点石斑鱼脑垂体近椭圆形,由神经垂体和腺垂体两部分组成。神经垂体主要由神经纤维、脑垂体细胞和微血管组成。其中神经分泌纤维存在A(A1、A2)和B型神经分泌纤维。腺垂体中外侧部(PPD)腺细胞由嗜酸性的GH细胞和嗜碱性的TSH细胞及GTH细胞3类细胞构成。在不同的时期,GTH细胞内的分泌颗粒明显不同。  相似文献   

3.
鲇脑垂体发生形态学的光镜和激光扫描共聚焦显微观察   总被引:6,自引:0,他引:6  
应用光镜和激光扫描共聚焦显微镜时鲇脑垂体发生形态学进行观察:鲇脑垂体由两个不同部位的胚胎细胞形成,原始口腔背壁外呸层分离出来的细胞构成腺垂体的前外侧部(RPD)和中外侧部(PPD),从间脑腹面漏斗体分离出来的细胞卡构成腺垂体中间部(PI)及神经垂体.3d龄仔鱼脑垂体的形态业已建成,属前后型.5d龄仔鱼脑垂体可区分出神经垂体及腺垂体,腺垂体可区分出RPD、PPD、和PI3个区域,并开始出现毛细血管.此时,PPD内的生长激素(GH)细胞已经分化.11d龄稚鱼脑垂体中除PPD内GH细胞已分化外,未见其它促激素分泌细胞分化.15d龄稚鱼脑垂体PPD内的促肾上腺皮质素(ACTH)细胞及催乳激素(PRL)细胞已分化.20d龄稚鱼脑垂体内各种激素分泌细胞完全分化.11d龄以前仔鱼脑垂体属前后型,15d龄和20d龄的稚鱼脑垂体内RPD、PPD和P13部分呈直状排列.性成熟鲇脑垂体结构旱背腹型.  相似文献   

4.
瓦氏黄颡鱼脑垂体组织学和组织化学研究   总被引:6,自引:1,他引:6  
对不同季节瓦氏黄颡鱼成鱼脑垂体进行组织学和组织化学研究.结果表明:瓦氏黄颡鱼脑垂体为背腹型腺体.神经垂体居中,前腺垂体位于垂体背面前部和后缘,由PRL细胞和ACTH细胞组成;中腺垂体位于垂体中部及背面后部,包括GH细胞、GTH细胞和TSH细胞,后腺垂体位于垂体腹面后方,组织学研究仅见一种分泌细胞.前腺垂体ACTH细胞形态、中腺垂体GTH细胞形态和数量在繁殖前后有明显变化,与生殖活动密切相关.  相似文献   

5.
用免疫组织化学方法观察了P物质在初孵扬子鳄脑垂体的分布特点.P物质阳性细胞分布于初孵扬子鳄脑垂体内侧腺垂体部,阳性纤维分布于初孵扬子鳄脑垂体外侧的神经部.结果表明P物质可能对垂体内分泌细胞有调节作用.  相似文献   

6.
运用组织学、组织化学技术对南方鲇成鱼垂体结构在生殖周期中的变化进行了研究.结果表明:南方鲇垂体为背腹型腺体,由神经垂体和腺垂体组成,神经垂体位于腺垂体中央;腺垂体前外侧部位于腺体前部,由PRL、ACTH细胞和少量GH、GTH细胞组成;中外侧部位于腺体中部及后部腹面区域,由GH、GTH和TSH细胞组成;中间部位于腺体后部背面,包括MSH、GTH细胞和首次在鱼类报道的大型泡状细胞.GTH和ACTH细胞结构在生殖周期中发生明显的变化,与生殖活动密切相关.  相似文献   

7.
鲤鱼神经垂体的超微结构研究   总被引:2,自引:0,他引:2  
经电子显微镜观察,提出鲤鱼神经垂体由有髓神经分泌纤维和三种无髓神经分泌纤维以及垂体细胞和毛细血管组成,神经分泌纤维与垂体细胞之间存在着突触联系,神经分泌纤维之间只有细胞间连接。在神经垂体组织中还存在Ⅰ型和Ⅱ型两种结构与功能不同的垂体细胞,另外在血管间道内观察到了很少见的特殊空泡结构。  相似文献   

8.
<正> 近年,生殖内分泌学的一个重大的进展是阐明了某些丘脑下部激素对生殖机能的调节控制与影响。这些激素是由丘脑下部的一些神经分泌细胞产生的,其分泌物不像神经递质一样进入突触间隙,而是进入血液循环,以真正激素的方式影响着远隔的器官。在较高等的动物,与生殖有关的此种激素主要有由丘脑下部视上核及室旁核分泌的催产素(OXY);丘脑下部促垂体区神经元分泌的肽类黄体生成素释放激素(LRH)。  相似文献   

9.
本文运用免疫胶体金电镜定位技术对团头鲂(Megalobrama Ambly cephala)(?)垂体(?)性腺激素细胞进行了钙素(CaM)的超微结构定位。钙调素分别标记在与激素蛋白合成及分泌有关的细胞核、粗面内质网和分泌颗粒中,表明 CaM 参与激素的合成和转运作用。此外,促性腺激素分泌细胞中的大颗粒和小颗粒上均有 CaM,说明这两种颗粒具有共性,均参与激素的分泌活动,这一结果进一步弄清了大、小颗粒的性质,为鱼类的生殖生理及人工催产机理的研究提供了有价值的资料。  相似文献   

10.
抗猪促卵泡激素小鼠源单克隆抗体的研究   总被引:3,自引:0,他引:3  
用猪促卵泡激素(PESH)作为抗原免疫BALB/C小鼠。通过将免疫小鼠的脾细胞和同系小鼠骨髓瘤细胞(SP2/O—Ag14)进行融合,建立了九株能稳定分泌抗PFSH单克隆抗体的杂交瘤细胞。其中三株杂交瘤细胞分泌的抗体被证实是对PFSH特异结合的,它们和另一种非常相近的垂体激素——猪促黄体激素(PLH)不结合。用有限稀释法对全部九株杂交瘤进行了三次亚克隆。有几种单克隆抗体被羟基磷灰石柱层析一步法从小鼠腹水所纯化。以聚丙烯酰胺凝胶电泳法检测经纯化单克隆抗体制品的纯度。  相似文献   

11.
Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.  相似文献   

12.
The Williston Basin is a significant petroleum province, containing oil production zones that include the Middle Cambrian to Lower Ordovician, Upper Ordovician, Middle Devonian, Upper Devonian and Mississippian and within the Jurassic and Cretaceous. The oils of the Williston Basin exhibit a wide range of geochemical characteristics defined as "oil families", although the geochemical signature of the Cambrian Deadwood Formation and Lower Ordovician Winnipeg reservoired oils does not match any "oil family". Despite their close stratigraphic proximity, it is evident that the oils of the Lower Palaeozoic within the Williston Basin are distinct. This suggests the presence of a new "oil family" within the Williston Basin. Diagnostic geochemical signatures occur in the gasoline range chromatograms, within saturate fraction gas chromatograms and biomarker fingerprints. However, some of the established criteria and cross-plots that are currently used to segregate oils into distinct genetic families within the basin do not always meet with success, particularly when applied to the Lower Palaeozoic oils of the Deadwood and Winnipeg Formation.  相似文献   

13.
王慧 《科技信息》2008,(10):240-240
Wuthering Heights, Emily Bronte's only novel, was published in December of 1847 under the pseudonym Ellis Bell. The book did not gain immediate success, but it is now thought one of the finest novels in the English language. Catherine is the key character of this masterpiece, because everybody and everything center on her though she had a short life. We can understand this masterpiece better if we know Catherine well.  相似文献   

14.
The discovery of the prolific Ordovician Red River reservoirs in 1995 in southeastern Saskatchewan was the catalyst for extensive exploration activity which resulted in the discovery of more than 15 new Red River pools. The best yields of Red River production to date have been from dolomite reservoirs. Understanding the processes of dolomitization is, therefore, crucial for the prediction of the connectivity, spatial distribution and heterogeneity of dolomite reservoirs.The Red River reservoirs in the Midale area consist of 3~4 thin dolomitized zones, with a total thickness of about 20 m, which occur at the top of the Yeoman Formation. Two types of replacement dolomite were recognized in the Red River reservoir: dolomitized burrow infills and dolomitized host matrix. The spatial distribution of dolomite suggests that burrowing organisms played an important role in facilitating the fluid flow in the backfilled sediments. This resulted in penecontemporaneous dolomitization of burrow infills by normal seawater. The dolomite in the host matrix is interpreted as having occurred at shallow burial by evaporitic seawater during precipitation of Lake Almar anhydrite that immediately overlies the Yeoman Formation. However, the low δ18O values of dolomited burrow infills (-5.9‰~ -7.8‰, PDB) and matrix dolomites (-6.6‰~ -8.1‰, avg. -7.4‰ PDB) compared to the estimated values for the late Ordovician marine dolomite could be attributed to modification and alteration of dolomite at higher temperatures during deeper burial, which could also be responsible for its 87Sr/86Sr ratios (0.7084~0.7088) that are higher than suggested for the late Ordovician seawaters (0.7078~0.7080). The trace amounts of saddle dolomite cement in the Red River carbonates are probably related to "cannibalization" of earlier replacement dolomite during the chemical compaction.  相似文献   

15.
Location based services is promising due to its novel working style and contents.A software platform is proposed to provide application programs of typical location based services and support new applications developing efficiently. The analysis shows that this scheme is easy implemented, low cost and adapt to all kinds of mobile nework system.  相似文献   

16.
以AC-13级配为基础,将橡胶颗粒代替部分集料掺入混合料中,以低温弯曲试验为评价方法对不同橡胶颗粒掺量下沥青混合料的低温抗裂性进行研究,并引入应变能密度值对混合料的低温抗裂性进行综合评价.试验结果表明:橡胶颗粒沥青混合料试件的破坏微应变均超过2 300,满足冬寒区的技术指标;无论是否掺加橡胶颗粒,随着温度的下降,沥青混合料破坏时的最大弯拉强度增大,弯拉应变降低,劲度模量增大;弯曲应变能密度在胶粒掺量为1%左右时具有较大的弯曲应变能密度值,此时橡胶颗粒沥青混合料具有较好的低温抗裂性.  相似文献   

17.
理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。  相似文献   

18.
Quality traits in wheat (Triticum aestirum L.) were studied by quantitative trait locus (QTL) analysis in a recombinant inbred line (RIL) population, a set of 131 lines derived from Chuan 35050 × Shannong 483 cross (ChSh). Grains from RILs were assayed for 21 quality traits related to protein and starch. A total of 35 putative QTLs for 19 traits with a single QTL explaining 7.99-40.52% of phenotypic variations were detected on 10 chromosomes, 1D, 2A, 2D, 3B, 3D, 5A, 6A, 6B, 6D, and 7B. The additive effects of 30 QTLs were positive, contributed by Chuan 35050, the remaining 5 QTLs were negative with the additive effect contributed by Shannong 483. For protein traits, 15 QTLs were obtained and most of them were located on chromosomes 1 D, 3B and 6D, while 20 QTLs for starch traits were detected and most of them were located on chromosomes 3D, 6B and 7B. Only 7 QTLs for protein and starch traits were co-located in three regions on chromosomes 1D, 2A and 2D. These protein and starch trait QTLs showed a distinct distribution pattern in certain regions and chromosomes. Twenty-two QTLs were clustered in 6 regions of 5 chromosomes. Two QTL clusters for protein traits were located on chromosomes 1D and 3B, respectively, three clusters for starch traits on chromosomes 3D, 6B and 7B, and one cluster including protein and starch traits on chromosome 1D.  相似文献   

19.
As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.  相似文献   

20.
赵英华 《科技信息》2008,(12):219-220
0.Preface China has long been boasting of its colorful and immense culture which comprises of Taoism,Confucianism and Buddhism.The interwoven influence among the religions on Chinese way of thinking,on the nation's behavior in their social life throughout the long history is beyond list.  相似文献   

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