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聚球藻藻胆体-类囊体膜吸收光谱中有五个吸收峰,它们位于420nm,438nm,490nm,624nm 和678nm。放氧速率为161—179mol O2/mg Chl.hr.电镜照片中显示在类囊体膜上有大量藻胆体。  相似文献   
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金鱼精子鞭毛发生的特点   总被引:7,自引:1,他引:6  
金鱼(Carassius auratus)是鲤形目鲤科硬骨鱼,精子为初级型,但在鞭毛上存在许多液泡。本文着重描述了在它的精子发生过程中,鞭毛形成的特点。现报告如下: 材料与方法 在不同季节从二龄金鱼(红龙睛)睾丸上不同部位取出小块组织,或在生殖季节用轻压腹部法挤出成热精子,即用2%戊二醛在室温下固定0.5小时,缓冲液稍洗后,在含0.8%亚铁氰化钾缓冲液内浸  相似文献   
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在不同季节,从成龄雄性金鱼(红龙睛Carassius auratus)的睾丸上几个部位取材,小块睾丸用亚铁氰化钾-四氧化锇方法固定,常规法脱水,Spurr包埋,切片。在电镜下对金鱼精子的发生进行了详细的比较研究,发现金鱼的初级精母细胞已经有鞭毛形成,有时还能在一个细胞内同时发现两根鞭毛存在。这是继国外  相似文献   
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光学衍射技术在当前已成为生物电子显微术中一个重要的组成部分,它不仅是高分辨率电镜工作所不可缺少的手段,而且还可以用来帮助处理电镜照片,分析样品的结构。我们利用自己改装的光学衍射仪观察分析了一些生物样品,充分显示了这种技术的优点。下面举例说明:  相似文献   
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金鱼精巢支持细胞间连接和血睾屏障   总被引:1,自引:0,他引:1  
Freeze-fracture and etching technique combined with thin sectioning and lanthanum impregnation has been used for the study of Sertoli cell junctions and the blood-testis barrier formation in goldfish testis with lobular organization. Some observations and results are first given in this paper. The results of experiments can be summarized as the following: 1). Sertoli cell junctions are compound junctions of tight junctions, desmosomes and gap junctions. Tight junctions usually appear as parallel or network like ridges on the P face and fine grooves on the E face at the freeze-etching replicas. Desmosomes and gap junctions often are located between or nearby the ridges of tight junctions. In addition, endoplasmic reticulum cristae near the junction area can also be observed. 2). The number, area and density of each individual junction vary with the development and differentiation stages of germinal cells in the cyst. 3). Tight junctions can be observed at any stage during germinal cell differentiation through the period of spermatogenesis and spermiogenesis. However, they appear morphologically different as type I and type II. 4). Lanthanum can partially penetrate into the intercellular spaces of spermatogonium and early primary spermatocyte but can't penetrate after the stage of late primary spermatocyte. 5). The blood-testis barrier formation starts at the stage of pachytene spermatocytes. The formation of the blood-testis barrier is the result of the development of the tight junction from type I to type II.  相似文献   
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生物学工作者对于普通的、加速电压为50—100千伏(kV)的透射式电镜及一般扫描电镜都已很熟悉,他们应用这类仪器来进行研究可以说已经达到了得心应手的程度。然而,大多数工作者对于在六十年代才在电镜家族中出现的新成员——高压电镜(指加速电压在500kV以上的电镜)的性能及它们在生物学中的潜力还不大了解。因而本文将把高压电镜的发展状况及在生物学上的应用作一扼要的介绍,供有兴趣的同志参考。  相似文献   
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金鱼精巢的细胞构造与精子的发生和形成   总被引:40,自引:2,他引:38  
  相似文献   
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金鱼精子质膜和核膜的区域特异性   总被引:6,自引:1,他引:5  
Combined SEM and TEM technique including thin sectioning, freeze-fracture and etching as well as cytochemical staining have been used for ultrastructural study on goldfish (Carassius auratus) sperm. It has been shown that primitive sperm plasma membrane and nuclear membrane are differentiated with regional specificity. The results from this study can be summarized as follows: 1. Intercalated protein particles are highly organized in the plasma membrane in the certain region of the head to form crystalline-like structure, in contrast rest of the area is rich in randomly or clustered particles. 2. Many vesicles in different size are often tightly packed in the head, neck and tail regions. Only these plasma membrane covering the vesicles contain almost no protein particles. 3. The vesicles can be densely stained cytochemically, suggesting the existence of glycoprotein. 4. Most of the nuclear membrane have no nuclear pores on it except the area near the neck part where many nuclear pores concentrate.  相似文献   
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本文首次报道用电子显微术观察兔肌甘油醛-3-磷酸脱氢酶(GAPDH)晶体及游离酶分子的结果,并进行了光学衍射分析和光学滤波处理。根据光学衍射图决定的二维投影晶胞参数为69.4(?)×67.6(?)(72°)。在电子显微镜下可以直接见到酶分子由四个亚基组成,这与生化分析及X 射线衍射分析结果相一致。  相似文献   
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