首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 83 毫秒
1.
中国鲎黄色结缔组织充满整个机体内部,填充于内脏器官之间,呈浅黄色或棕褐色,为鲎体内重要的组织结构,黄色结缔组织由多种类型的细胞和丰富的细胞间质组成,构成细胞主要有营养细胞、血细胞、类巨噬细胞以及干细胞等,营养细胞是其主要的组成细胞,内含丰富的营养颗粒和脂肪颗粒,鲎的黄色结缔组织分布有大量的造血组织,前体部的黄色结缔组织中分布有数量众多的中肠盲囊。  相似文献   

2.
中国鲎的血细胞发生于黄色结缔组织中弥散的造血组织.透射电镜观察结果表明.鲎造血组织中血细胞发生过程经历以下几个阶段:血母细胞、原血细胞,浆血细胞和颗粒血细胞.血母细胞位于造血组织中,被基膜包围,核质比大.原血细胞,胞质有所增大。细胞器较少。含少量膜泡.浆血细胞,胞质增大许多,内质网膜大量膜泡化.膜泡内沉积物不断生成,最终发育为血细胞特异性颗粒.早期颗粒血细胞内含少量的大小颗粒.随着细胞内大量大小颗粒的生成,细胞分化进人晚期颗粒血细胞阶段.即将成熟的血细胞逐渐脱离造血组织,移向血窦腔隙.在血淋巴中进一步成熟.  相似文献   

3.
鲎血淋巴系统的特点及其功能   总被引:2,自引:0,他引:2  
鲎的血淋巴系统由心脏、血管和血淋巴液组成.心脏和血管系统非常发达,而且血液量巨大.血淋巴液由血浆和血细胞组成.血浆主要含有血蓝蛋白、02—巨球蛋白、C—反应蛋白等.对鲎血细胞的种类,看法不一,其主要的血细胞类型为颗粒性血细胞,其胞质中含有特征性的大小颗粒.鲎的血淋巴中含有50种以上的免疫因子,大都位于大小颗粒中,它们在鲎的天然免疫中起重要的作用.  相似文献   

4.
用电子显微镜对杜仲叶脉韧皮部超微结构进行了观察,发现叶小脉韧皮部筛管分子比伴胞小;含胶细胞的细胞器退化消失,细胞腔内充满了橡胶颗粒;传递细胞的细胞壁向内形成乳突状突起,这种突起在细胞中的数量少,但特别大而长,这种特有的形态结构,可作为1种鉴定特征.  相似文献   

5.
对润楠(Machilus pingii Cheng ex Yang)花粉生殖细胞和营养细胞的形成进行了观察.结果如下:(1)随着小孢子核向(?)方向迁移,胞质的线粒体和前质体显著增多;由于大液泡的存在,细胞器偏向核的一侧分布.(2)小孢子有丝分裂末期,胞质中出现较多的高尔基体和微管.(3)生殖细胞(?)抵达花粉内壁后,生殖细胞和营养细胞的胞质中出现大量与壁平行排列的粗面内质网.随着生殖细胞壁的加厚, 生殖细胞的局部与营养细胞核相贴近,贴近区域的生殖细胞质中出现交织成网的内质网.(4)游离的生殖细胞具,胞质中仅有少量细胞器;营养细(?)中储存有大量的淀粉粒.从观察结果推测:影响润楠生殖细胞在花粉内进一步分裂的因素可能有三种:一是生殖细胞壁留存的时间;二是营养细胞和生殖细胞本身的代谢状况;三是营养细胞核对生殖细胞的作用.  相似文献   

6.
对锯缘青蟹氵蚤状幼体I期不同营养状态下(饥饿或投饵)肝胰腺细胞的超微结构进行了研究,实验表明,不同营养状态下肝胰腺细胞结构发生了较明显的变化,特别是R细胞某些胞器(如线粒体结构变化和微体颗粒数量和分布的变化)的变化与幼体的营养状态存在有密切的关系,在一定程度上可以表征幼体所处的营养状态,可作为营养状况的生理指标.  相似文献   

7.
中国鲎鲎素对人胃腺癌BGC-823细胞形态和超微结构的影响   总被引:5,自引:3,他引:2  
应用从中国鲎血液中提取的鲎素处理人胃腺癌BGC-823细胞,研究鲎素对胃癌细胞形态和超微结构的影响,光镜观察显示经2.0μg/mL鲎素处理的BC-823细胞形态较为一致,细胞体积增大,趋于扁平铺展状态,细胞核质比例变小,核仁数量减少、体积缩小、扫描电镜与透射电镜观察可见经鲎素处理后BGC-823细胞表面微绒毛稀少,细胞边缘丝状伪足减少,片状伪足增多;细胞核形态较规则,核内异染色质减少,常染色质增多;细胞质内线性粒体量增多,结构较为一致,高尔基于较为典型发达状态,并出现粗人质网增多和多聚核糖体减少等变化,结果表明,鲎素能有效改变胃癌细胞恶性形态结构特征,从而对胃癌细胞具有一定的诱导分化作用。  相似文献   

8.
犬卵母细胞体外成熟培养前后的超微结构变化   总被引:2,自引:0,他引:2  
从屠宰场采集犬卵巢,收集间情期(不可见卵泡)和发情期卵巢卵母细胞。成熟培养前,其超微结构有以下特征:间情期犬卵母细胞与卵丘细胞间以及卵丘细胞之间通过胞质突起相连,胞质中的主要细胞器是线粒体和脂滴,质膜下有发达的粗面内质网;囊状卵泡的卵母细胞,结构近似于间情期犬卵母细胞,但细胞间连接更为普遍,胞质中细胞器更加丰富,并出现零星的皮质颗粒。经TCM199+20%FCS+10IU/mLFSH体外培养36h后,微绒毛、线粒体、滑面内质网、皮质颗粒等细胞器增多,胞质内细胞器向皮质区迁移,核仁发生致密化。体外培养72h后,卵母细胞进一步成熟,表面微绒毛由倒伏状变得细长且坚起,皮质颗料沿质膜下呈线行排列,线粒体分散于皮质中央  相似文献   

9.
许氏平鲉消化道的组织化学研究   总被引:6,自引:0,他引:6  
运用组化方法对许氏平鲉消化道碱性磷酸酶、酸性磷酸酶、羧酸酯酶和粘液物质进行了定位及半定量研究。发现幽门盲囊和肠上皮细胞顶端胞质和纹状缘具碱性磷酸酶活性;胃粘膜上皮细胞核上方胞质、幽门盲囊及肠上皮细胞顶端胞质中检测到酸性磷酸酶活性;在胃贲门部和盲囊部、鼬门盲囊以及肠的上皮细胞内还检测到羧酸酯酶活性。整个消化道的粘膜层中存在许多粘液细胞。食道上皮含大量酸性粘液细胞,胃上皮细胞均含有中性粘液,而肠道由前向后中性粘液物质逐渐减少酸性粘液物质逐渐增多。研究结果表明许氏平鲉食道和直肠有润滑和微弱的吸收作用,胃有消化雕类和吸收二糖及短链脂肪的功能;幽门盲囊有较强的吸收脂类的功能;前肠、中肠和后肠有活跃的细胞内消化和吸收功能。  相似文献   

10.
四分体内各小孢子之间具有发达的胞质通道可见各种细胞器穿过此通道,初期的生殖细胞和营养细胞的细胞质中的细胞器没有明显差异,但在以后发育中,生殖细胞和营养细胞表现出明显的异质性,生殖细胞中始终未发现质体,其它细胞器不仅数量少,而且体积小,结构简单。与此相反,营养细胞内各种细胞器明显增多,而且体积大,结构发达,质体内可见有淀粉的沉积,特别值得指出的是,在营养细胞中发现一种结构较特殊的质体,这一现象在其它植物中尚未见报道过。  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   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号