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1.
采用荧光紫杉醇直接荧光标记,研究了腹毛类纤毛虫阔口游仆虫(Euplotes eurystomus)中由纤毛器、纤毛器附属微管和非纤毛器微管组成的皮层微管胞器.其中纤毛器、纤毛器附属微管包括口围带及小膜托架微管,波动膜及基部微管骨架网,额腹横棘毛、左缘棘毛及基部的前纵维管束、后纵微管束和横微管束,背触毛及基部的玫瑰花环附属微管等;非纤毛器皮层微管包括背腹面的细小网格状微管,背面的斜向微管层及贯穿于细胞纵长的纵微管层等.形态发生中,老口围带被前仔虫继承,前、后仔虫的额腹横棘毛发生及分化过程中老纤毛器基部微管退化,并且老棘毛及其附属微管可能具有定位和定向作用,但未见直接的物质联系.所得结果为揭示腹毛目纤毛虫皮层微管胞器建构的多样性、细胞皮层微管的分化及其细胞调控提供了基础资料.  相似文献   

2.
应用荧光紫杉醇直接荧光标记和抗a-微管蛋白抗体免疫荧光标记,显示了纤毛虫小腔游仆虫(Euplotes aediculatus)皮层纤毛器微管、纤毛器基部附属微管和背皮层表面微管等结构,以及皮层纤毛器微管的形态发生.结果表明,该游仆虫背皮层表面网在形态上与嗜银网相一致,也是一种微管类细胞骨架;与其他几种游仆虫比较,前仔虫口纤毛器和背皮层纤毛器微管的形态发生存在不同的模式,其形态发生可能具有种的特异性,可以作为种的分类依据之一.此外,与FLUTAX(fluorescence taxoid)标记方法相比较,抗α-微管蛋白抗体免疫荧光标记能较清晰地显示游仆虫背皮层表面微管网及早期发生的额腹横棘毛原基和背触毛原基,推测该游仆虫的细胞背表面微管网与其他微管结构其微管蛋白组分可能存在差异,且形态发生中伴随着皮层纤毛器微管的组装和成熟,其微管蛋白组分同时也在不断发生变化.  相似文献   

3.
采用透射电镜术显示腹毛类纤毛虫阔口游仆虫(Euplotes eurystomus)的微管类细胞骨架包括纤毛器微管骨架和非纤毛器微管骨架.结果表明:细胞皮层纤毛器中除纤毛杆、纤毛基体微管外,其基体间连接纤维、基体托架、基体附属微管、纤毛器基部附属微管束以及围棘纤维篮等也是皮层纤毛器微管的重要组成部分,各种微管相互联系、聚...  相似文献   

4.
异毛虫Allotricha curdsi皮层纤毛器基部微管的荧光标记   总被引:7,自引:0,他引:7  
FLUTAX直接荧光标记和抗α-微管蛋白抗体免疫荧光标记显示,原生动物腹毛目纤毛虫异毛虫(Al-lotricha curdsi)细胞微管胞器由口围带、波动膜、额腹横棘毛、左右缘棘毛、背触毛等皮层纤毛器、纤毛器基部附属微管组成.其中腹面皮层纤毛器基部附属微管包括小膜托架、小膜附属微管、波动膜骨架;额腹横棘毛基部围棘纤维篮、额腹横棘毛和左右缘棘毛基部前纵微管束、后纵微管束和横微管束,它们以各自的纤毛器基部为中心,分别向皮层不同方向发射,在细胞皮层内形成一个复合三维结构微管网;并且,左、右缘棘毛基部横微管显示非镜像对称的图像,横棘毛基部微管前纵微管束向前伸展后其前端并非聚集在一起,这与目前报道的其他腹毛目纤毛虫如贻贝棘尾虫、魏氏拟尾柱虫同种结构的定位特征不一样.  相似文献   

5.
包囊游仆虫表膜含有质膜和表膜泡。表膜下纵纤维层中其腹面由单根微管纵向排列组成,背面由每三根微管形成“品”字形微管单元,背面银线网是一种真实的嗜银结构,它可能是表膜泡结构间隙中的沉积物;细胞皮层中非纤毛器细胞骨架主要包括束状、网状骨架系统以及其他一些微管束,纤毛器细胞骨架其基体间含有托架及其连接纤维,基体并向细胞质放射出纤维。另外,小根纤维由多根微管在一起组成,基体及有关微管纤维形成具有不同的连接方  相似文献   

6.
包囊游仆虫纤毛器微管在不同生理状态下的分化   总被引:2,自引:0,他引:2  
应用FLUTAX染色及荧光显微术研究了包囊游仆虫的皮层微管胞器及其形成包囊和脱包囊过程中结构的分化:(1)细胞无性分裂过程中,棘毛基部的毛基体由紧密聚集状态逐渐分离、瓦解和消失;背纤毛基体逐渐膨大,基体内的周围微管散开成梅花形,之后在相应皮层区发生由颗粒组成的条带形原基.(2)细胞形成包囊时,口围带、波动膜和额腹横棘毛等微管胞器经历了部分去分化的过程,伴随着细胞体的凝缩,其纤毛器相互聚集,定位于球形体包囊细胞腹面;背纤毛按原有模式排列,位于包囊细胞背面.(3)脱包囊过程中,细胞吸水膨大,细胞体分化成变形虫状并显示一致的弱荧光,但未见微管胞器的荧光图像;细胞通过包囊壁背面小孔脱囊而出,恢复成为正常形态的纤毛虫;此后,在细胞脱包囊后残留的包囊壁背壁尚保存有部分背纤毛的痕迹.根据所得结果推测,形态发生中,纤毛器微管对新结构的形成可能有物质联系或物质贡献;脱包囊时,细胞成变形虫状,其微管结构可能发生了解聚和再分化的过程.  相似文献   

7.
华美游仆虫皮层细胞骨架的超微结构及免疫电镜观察   总被引:1,自引:0,他引:1  
 应用透射和免疫电镜术,在超微结构水平观察显示,腹毛类纤毛虫华美游仆虫的皮层纤毛器和非纤毛器细胞骨架中,表膜下、细胞质深部的微管或纤维束,以及纤毛器及纤毛器附属微管等均是以α-和 β-微管蛋白为主要成分的微管类结构;中心蛋白定位于纤毛器的基体腔、基体基部近中心端、基体基部近中心端连接及基体中部连接结构中,而在纤毛杆和皮层非纤毛器微管中无中心蛋白成分存在。据此认为,该纤毛虫中,基体部位的蛋白组成机制与纤毛杆及纤毛器附属结构是不同的,非分裂期细胞中定位于基体主体部位的中心蛋白可能与维持相关结构的稳定性有关。  相似文献   

8.
包囊游仆虫的皮层及其纤毛结构的形态学研究   总被引:1,自引:0,他引:1  
应用光学显微镜和扫描电子显微镜研究了非分裂时期和分裂时期上海包囊游仆虫的皮层及其纤毛结构的形态学。形态发生中,纤毛原基按口原基,额腹横棘毛、尾棘毛、和背触毛原基的顺序先后在皮层内发生和分化,皮层相应位置也按序形成纤毛原基生长发育的空间。纤毛原基长纤毛时,其上方皮层表面裂开,伴同着新口围带逐渐外露,或新棘毛沿皮层裂口形成的沟槽迁移和定位。皮层表面突起中,唇和第二条脊经历生长发育和分裂的过程,被分配到前、后仔虫中,其中脊向仔细胞传递的这种现象是特殊的。所得结果表明,游仆虫的老口围带纤毛结构发生更新后形成前仔虫的口围带,并且前仔虫波动膜也可能是更新后产生的新结构。  相似文献   

9.
包囊游仆虫的皮层及其纤毛结构的形态学研究   总被引:3,自引:2,他引:3  
应用光学显微镜和扫描电子显微镜研究了非分裂时期和分裂时期上海包囊游仆虫的皮层及其纤毛结构的形态学.形态发生中,纤毛原基按口原基,额腹横棘毛、尾棘毛、和背触毛原基的顺序先后在皮层内发生和分化,皮层相应位置也按序形成纤毛原基生长发育的空间.纤毛原基长纤毛时,其上方皮层表面裂开,伴同着新口围带逐渐外露,或新棘毛沿皮层裂口形成的沟槽迁移和定位.皮层表面突起中,唇和第二条脊经历生长发育和分裂的过程,被分配到前、后仔虫中,其中脊向仔细胞传递的这种现象是特殊的.所得结果表明,游仆虫的老口围带纤毛结构发生更新后形成前仔虫的口围带,并且前仔虫波动膜也可能是更新后产生的新结构.  相似文献   

10.
中心蛋白与中心体(或基体)有着密切关系,作为一种细胞骨架蛋白,形成原生动物巨大的细胞骨架网络;为了研究从八肋游仆虫细胞中克隆到的一种中心蛋白基因(EoCen3)的功能,我们构建了八肋游仆虫细胞大核人工染色体pBTub-Tel,定位分析该基因所表达的中心蛋白在细胞中的分布和行为.该人工染色体利用密码子优化的增强型绿色荧光蛋白基因作为标记,在八肋游仆虫细胞中实现高表达,避免用抗生素作为标记对该细胞的喂养产生影响.定位结果显示,该类中心蛋白特异定位于游仆虫形态发生过程中的基体上.在八肋游仆虫无性生殖细胞分裂的起始阶段基体开始发育,首先形成第一个基体,Eo-Cen3定位于新形成的基体中;随后基体开始复制,EoCen3定位于正在复制的基体中.在细胞发育过程中绿色荧光标记的基体成倍增加,说明EoCen3与参与棘毛形成的基体的复制有一定的关系.  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.
何延凌 《科技信息》2008,(4):258-258
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.
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   

14.
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   

15.
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   

16.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  相似文献   

17.
There are numerous geometric objects stored in the spatial databases. An importance function in a spatial database is that users can browse the geometric objects as a map efficiently. Thus the spatial database should display the geometric objects users concern about swiftly onto the display window. This process includes two operations:retrieve data from database and then draw them onto screen. Accordingly, to improve the efficiency, we should try to reduce time of both retrieving object and displaying them. The former can be achieved with the aid of spatial index such as R-tree, the latter require to simplify the objects. Simplification means that objects are shown with sufficient but not with unnecessary detail which depend on the scale of browse. So the major problem is how to retrieve data at different detail level efficiently. This paper introduces the implementation of a multi-scale index in the spatial database SISP (Spatial Information Shared Platform) which is generalized from R-tree. The difference between the generalization and the R-tree lies on two facets: One is that every node and geometric object in the generalization is assigned with a importance value which denote the importance of them, and every vertex in the objects are assigned with a importance value,too. The importance value can be use to decide which data should be retrieve from disk in a query. The other difference is that geometric objects in the generalization are divided into one or more sub-blocks, and vertexes are total ordered by their importance value. With the help of the generalized R-tree, one can easily retrieve data at different detail levels.Some experiments are performed on real-life data to evaluate the performance of solutions that separately use normal spatial index and multi-scale spatial index. The results show that the solution using multi-scale index in SISP is satisfying.  相似文献   

18.
In the 19th century the society was controlled by men, and women were just appendants of them, they had not any rights and freedom. But Jane was an exception, she showed some characteristics of early feminist. Jane showed her characteristics of feminism in three aspects: rebellion, equality, and independence. These characteristics were helpful to her success, and feminism is the only way out for women of that time.  相似文献   

19.
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   

20.
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   

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