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Ueda H Takehana K Eerdunchaolu Iwasa K Fujimori O Shimada S 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2001,63(3):287-291
The distribution patterns of the intensity of negative charge on the free surfaces (glycocalyx of the plasma membrane) of endothelial cells (ECs) in blood vessels and reticular cells (RCs) in the splenic cord of the rat spleen were studied by an electron microscopic cytochemical method using polyethyleneimine (PEI) as a cationic probe. Spleens from adult male rats were perfusion-fixed with 0.5% glutaraldehyde -4% paraformaldehyde containing 0.05% cetylpyridinium chloride and then perfused with 0.5% PEI at pH 7.4. On the free surfaces (glycocalyx of the plasma membrane) of the ECs examined, distinct PEI-positive reactions were observed in blood vessels, such as trabecular arteries, central arteries, arterial capillaries, pulp veins and trabecular veins. These PEI-positive electron-dense substances in the trabecular arteries, central arteries, and trabecular veins took the shape of a band of 170-250 nm in thickness. On the other hand, the corresponding ultrastructure of the ECs lining the splenic sinuses and the RCs in the splenic cord showed exceedingly weak PEI reactions. The PEI-reactive deposits were significantly thinner than those in the above blood vessels. As the thickness of the electron-dense substances can be related to the density of the negative charge, these results suggest that there is a high intensity of negative charge on the free surfaces (glycocalyx of the plasma membrane) of ECs in blood vessels where blood cells and plasma pass into the red pulp or are discharged from the red pulp. In contrast, the splenic sinuses and RCs, which are the main components of the red pulp, contain weakly negative-charged sites. This may contribute to the microcirculation of the splenic blood vessels and elucidate the possible physiological functions of the spleen, such as blood storage. 相似文献
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综述了近年来对抛物线性限制势量子点中强耦合双极化子和磁双极化子的部分研究工作.从抛物量子点中2个电子-声子体系的哈密顿量出发,采用Lee-Low-Pines-Huybrechts变分方法,研究了量子点中强耦合双极化子的振动频率、诱生势和有效势随电子-声子耦合强度、两电子相对距离和量子点半径的变化规律;采用Tokuda改进的线性组合算符法研究了温度和LO声子效应对强耦合双极化子的有效质量和平均声子数的影响.基于Lee-Low-Pines幺正变换,采用Pekar类型变分法研究了抛物量子点中强耦合磁双极化子的内部激发态性质,当考虑自旋和外磁场影响时,研究了二维量子点中强耦合磁双极化子基态的能量、声子平均数以及第一激发态的能量、声子平均数随量子点受限强度、介电常数比、电子-声子耦合强度和磁场的回旋共振频率的变化规律. 相似文献
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. Eerdunchaolu K. Takehana A. Kobayashi . Baiyin G. -F. Cao A. Andrén K. Iwasa M. Abe 《Anatomia, histologia, embryologia》1999,28(3):183-191
The morphology of the gland cells in the glandular sac area of the Bactrian camel and the composition of secretory substances were examined by histochemical methods. It was found that the gland cells of the glandular sac area were of the same type and size as those of the cardiac glands. The composition of secretory substances from the glandular sac area was the same as that of secretory substances from the cardiac glands. Moreover, secretory substances from the gland cells of the glandular sac area contained a great deal of acid glycoconjugates, such as sialic acid, in addition to neutral saccharides (fucose, mannose, glucose, N-acetyl-D-glucosamin, galactose and N-acetyl-galactosamin). Furthermore, immunohistochemical examination showed that progastricsin was present in the gland cells of the glandular sac area and the cardiac gland. In this study, histological analysis suggested that the stomach of the Bactrian camel is a single cavity stomach, formed as a result of multiple differentiation and growth of cardiac glands through the process of evolution. 相似文献
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