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1.
中华稻蝗卵子发生的观察 总被引:6,自引:0,他引:6
对直翅目蝗总科中华稻蝗[Oxya chinesis(Thunberg)]卵子发生过程进行细胞学观察及阶段划分,成虫期卵子发生可分为卵母细胞分化、卵母细胞营养及卵母细胞卵黄形成3个时期,并且可划分为8个阶段:第l阶段,卵母细胞位于卵原区,进行第一次减数分裂前期;第2阶段,卵母细胞增大,滤泡上皮细胞开始出现;第3阶段,滤泡上皮细胞呈扁平状排列为一层包围在卵母细胞外,卵室内有空隙;第4阶段,滤泡上皮细胞呈立方形,卵室内无空隙,胚泡向卵质周缘移动;第5阶段,卵母细胞体积增大,滤泡上皮细胞长柱状,细胞间开始出现空位;第6阶段,卵母细胞胞质周缘有泡状小体出现并有卵黄颗粒积累;第7阶段,卵母细胞胞质内充满了染色较深的卵黄球,卵黄物质逐渐被卵黄膜包被,胚泡膜消失;第8阶段,卵黄积累完成,滤泡上皮细胞分泌卵壳蛋白凝聚固化而成为卵壳。 相似文献
2.
目的 白蚁的品级分化和发育与其性腺成熟有密切的关系,通过对尖唇散白蚁(Reticulitermes aculabialis)卵子发生的研究,为进一步探讨其生殖生理和品级分化的分子调节机制打下基础。方法 取雌性末龄若虫和分飞成虫腹部,Bouin氏液固定,常规石蜡切片6μm,HE染色。结果 卵子发生分为卵母细胞分化期、生长期及卵黄形成期,并细分为7个阶段:第1阶段,卵母细胞处于卵原区进行第1次减数分裂的前期;第2阶段,核仁消失,滤泡细胞开始分化;第3阶段,滤泡细胞包围卵母细胞后成为双核的柱状体;第4阶段,卵黄颗粒出现;第5阶段,卵母细胞积累大量卵黄;第6阶段,滤泡细胞变为柳叶状,卵黄积累完成;第7阶段,卵壳形成。结论 在卵子发生的过程方面,白蚁与其他昆虫基本相同。即:卵黄发生是卵子发生过程中的关键阶段;滤泡细胞在卵黄发生期非常活跃,参与了卵黄的形成,并且有可能直接调节卵子的成熟。 相似文献
3.
用组织学方法对短额负蝗卵子发生和卵母细胞凋亡进行了显微观察.根据卵母细胞的大小、形态、胞核的变化、卵黄物质的形成以及滤泡细胞的形态变化等特征,将短额负蝗卵子发生分为3个时期8个阶段,并描述了各个阶段卵母细胞和滤泡细胞的形态特征.卵子发生过程中卵母细胞凋亡现象主要发生在卵母细胞生长期,特征主要表现为滤泡细胞向卵母细胞质内分裂增殖,卵母细胞的胞质不均匀,出现许多空泡状物质. 相似文献
4.
北京油葫芦卵子发生的观察 总被引:3,自引:1,他引:3
对北京油葫芦(Teleogryllus emma Ohmachi & Matsuura)卵子发生过程进行了系统观察和研究.结果表明,成虫期卵子发生可明显的分为卵母细胞分化、生长及卵黄形成三个时期,并可分为七个阶段.第一阶段,卵母细胞位于卵原区,进行第一次减数分裂的前期.第二阶段,卵母细胞核内核仁消失,滤泡上皮细胞开始分化.第三阶段,滤泡上皮细胞有丝分裂形成单细胞层包围在卵母细胞外,之后滤泡上皮细胞形成双核的柱状体.第四阶段,卵母细胞胞质的周缘有泡状小体出现,随后卵黄小颗粒开始在胞质周缘沉积.第五阶段,卵母细胞积累大量卵黄物质,胚泡膜界限变的模糊.第六阶段,卵黄积累完成,胚泡消失,滤泡上皮细胞又成为扁圆形.第七阶段,卵黄膜和卵壳形成,卵子发育成熟. 相似文献
5.
利用透射电镜技术观察了中华绒螯蟹卵子发生过程中卵母细胞表面和滤泡细胞超微结构的变化.结果显示:从卵原细胞期到卵黄大量合成时期,滤泡细胞逐渐向卵母细胞迁移,细胞膜向外伸出许多突起,胞质中的细胞器逐渐增多,它们与卵黄蛋白物质一同移入卵周隙.到卵黄合成晚期,滤泡细胞逐渐解体.与此同时卵母细胞表面在卵黄发生初期可见微胞饮小泡;卵黄大量发生期出现大量微绒毛;卵黄合成晚期,卵黄膜形成,卵黄膜上出现多条通道,这些结构为卵母细胞吸收来自滤泡细胞的卵黄蛋白物质提供了保障. 相似文献
6.
以鲶卵巢为材料,研究了卵巢和卵母细胞发育的形态结构特点。鲶卵巢的发育划分为6期,其卵母细胞相应地划分为6个时相,第一时相的卵母细胞呈原始分化状态,细胞外具一层细胞质膜,第二时相卵母细胞外不仅具质膜,而且还有滤泡膜和结缔组织膜。第三和第四时相的卵母细胞分化明显,由散在的卵黄沉积逐渐形成大的卵黄颗粒。第四时相卵母细胞具有漏斗状的精孔及椭圆形的精孔细胞。第五时相和第六时相分别为卵子形成和退化吸收时相。 相似文献
7.
罗氏沼虾(Macrobrachium rosenbergii)卵子发生的细胞化学研究 总被引:4,自引:0,他引:4
本研究应用细胞化学方法研究了罗氏沼虾卵子发生过程中主要生物大分子的变化。从卵原细胞到卵母细胞的发育过程中,核酸逐渐分散,蛋白质大量沉积。尽管卵原细胞和卵黄发生前的卵母细胞中,PAS和苏丹黑反应为阴性,但随着卵母细胞被滤泡细胞包围,这两种反应阳性物质在卵母细胞质中大量出现,似乎表明滤泡细胞可以向卵母细胞提供糖类和脂类或能构成糖类、脂类的物质。成熟卵子内含有大量蛋白质、糖类和脂类,为此后的胚胎发育作好了准备。 相似文献
8.
锯缘青蟹卵子发生的超微结构研究 总被引:11,自引:2,他引:11
锯缘青蟹的卵子发生可划分为卵原细胞,卵黄发生前期和卵黄发生期卵母细胞三个时期,卵原细胞核大而圆,卵质稀少,胞器以滑面内质网为主。卵黄发生前的卵母细胞核显著膨大,部分核内可见到同源染色体的联会现象:卵质细密,出现核仁外排物和大量的核糖体,粗面内质网,线粒体和自噬泡,卵黄发生的卵母细胞核膜上核孔密集;卵质中各种胞器高度发达,参与形成卵黄粒和脂滴;细胞出现微吞饮活动并形成卵黄膜,细胞外围单层滤泡细胞,本 相似文献
9.
本研究应用细胞化学方法研究了罗氏沼虾卵子发生过程中主要生物大分子的变化。从卵原细胞到卵母细胞的发育过程中,核酸逐渐分散,蛋白质大量沉积。尽管卵原细胞和卵黄发生前的卵母细胞中,PAS和苏丹黑反应为阴性,但随着卵母细胞被滤泡细胞包围,这两种反应阳性物质在卵母细胞质中大量出现,似乎表明滤泡细胞可以向卵母细胞提供糖类和脂类或能构成糖类,脂类的物质。 相似文献
10.
从组织学方面研究了白棘三列海胆生殖系统的构造及其性腺发育分期.结果表明,白棘三列海胆的生殖腺为5列,由系膜悬挂于各生殖腔内.卵巢为滤泡型,在滤泡的边缘为卵原细胞和卵黄形成前期卵母细胞,而在滤泡的内部为卵黄形成初期卵母细胞、卵黄形成后期卵母细胞和成熟卵细胞,当卵母细胞内的卵黄完成积累后,经两次成熟分裂,分裂为成熟卵子.精巢也为滤泡型,精原细胞由滤泡壁原始的生殖细胞产生,进而依次发育为初级精母细胞、次级精母细胞、精细胞和精子.白棘三列海胆生殖腺发育周期可分为:恢复期、生长期、成熟前期和排放后期,通过解剖观察及组织切片显示,全年中除5月份之外,其余各月份均可进行白棘三列海胆的人工繁殖. 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.
Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women's language from these perspectives: pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women's language, more attention should be paid to language use in social context. What's more, the linguistic phenomena in a speaking community can be understood more thoroughly. 相似文献
13.
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 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
15.
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
16.
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
17.
Miao Maosheng 《华南师范大学学报(自然科学版)》2014,(6)
正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula- 相似文献
18.
Yang Weitao 《华南师范大学学报(自然科学版)》2014,46(6):137-138
We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re- 相似文献
19.
Bernard Kirtman 《华南师范大学学报(自然科学版)》2014,(6)
正The electronic and nuclear(structural/vibrational)response of 1D-3D nanoscale systems to electric fields gives rise to a host of optical,mechanical,spectral,etc.properties that are of high theoretical and applied interest.Due to the computational difficulty of treating such large systems it is convenient to model them as infinite and periodic(at least,in first approximation).The fundamental theoretical/computational problem in doing so is that 相似文献
20.
《上海师范大学学报(自然科学版)》2014,(5):550
<正>"The Journal of Shanghai Normal University:Mathematics"is published by Shanghai Normal University as regular issues of The Journal of Shanghai Normal University each year from 2014 in English.The editors-in-chief of the issues are professors Yuhao Cong and Maoan Han.The Journal of Shanghai Normal University was started in 1958 with 相似文献