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11.
Motoki Tagami Kazuo Yamagata Hideaki Fujino Akiyoshi Kubota Yasuo Nara Yukio Yamori 《Cell and tissue research》1992,268(2):225-232
Summary In this study bovine aortic endothelial cells were co-cultured with astrocytes from fetal Wistar Kyoto rats. Endothelial cells growing on type-I collagen, development. Although some cells appeared to be mature, horseradish peroxidase penetrated within 1 min of incubation through the intercellular junctions of these endothelial elements maintained on type-I collagen. In contrast, endothelial cells on type-IV collagen, co-cultured with astrocytes, were well developed; their intercellular junctions were well established, and plasmalemmal vesicles reduced in number. As a result, horseradish peroxidase was unable to penetrate through the endothelial cells grown on type-IV collagen and co-cultured with astrocytes because of the reduced extent of the junctional and vesicular transport. These findings reveal that (1) type-IV collagen is essential for the differentiation of endothelial cells, (2) endothelial cell-astrocyte interactions occur during co-culture, and (3) endothelial permeability depends on astrocyte-produced factors, in addition to type-IV collagen. 相似文献
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A major plasma protein, referred to as SP 1, exhibits sex- and stage-specific expression during the larval development of the silkworm, Bombyx mori. We have isolated a plasmid clone bearing a part of mRNA sequence coding for SP 1 and quantitated the amount of SP 1 mRNA by means of RNA blot hybridization using the cDNA probe. The developmental change in the amount of SP 1 mRNA in the fat body closely reflected that of the hemolymph concentration of SP 1, indicating that the biosynthesis of SP 1 is regulated in a sex- and developmental stage-specific fashion at the level of mRNA. 相似文献
14.
Non-cycling pluripotent bone marrow stem cells (CFU-S), taken 3 hrs after injection of 20 mg of Ara-C, have been shown to enter DNA synthesis at 1 to 3 hr after being cultured in alpha-medium. This phenomenon was observed when bone marrow was incubated as a plug, but not when incubated as a cell suspension in the present experimental conditions. These results suggest that a medullary structure is necessary in order to observe this effect and/or that accessory cells are destroyed during the process of single cell preparation. 相似文献
15.
A chymotrypsin-type serine protease in rat basophilic leukemia cells: evidence for its immunologic identity with atypical mast cell protease 总被引:2,自引:0,他引:2
H Kido K Izumi H Otsuka N Fukusen Y Kato N Katunuma 《Journal of immunology (Baltimore, Md. : 1950)》1986,136(3):1061-1065
Activity of a chymotrypsin-type serine protease was found in a subline of rat basophilic leukemia (RBL-2H3) cells. The protease was immunologically cross-reactive with anti-atypical mast cell protease immunoglobulin (Ig) G, and its activity was inhibited in a dose-dependent manner by the antibody. The apparent m.w. of the protease that reacted with the antibody was 25,000, which was identical with that of atypical mast cell protease in rat mucosal mast cells. These results show that the chymotrypsin type serine protease in RBL-2H3 cells is immunologically identical with atypical mast cell protease, which was first purified from rat small intestine. Immunohistochemical studies showed that the protease was located not only in intracytoplasmic granules but also in organelles synthesizing protein, such as cisternae of the rough endoplasmic reticulum, perinuclear spaces, and the Golgi apparatus. However, no immunoreactivity was demonstrated in rat basophils. The activity of the protease increased in the exponential phase of growth of RBL-2H3 cells in which some activity was also detected in the medium, and it decreased in the late stationary phase. 相似文献
16.
T Hasegawa S Izumi S Kurihara Y Ishizuka Y Ito A Takechi M Tsuchiya 《Acta cytologica》1985,29(3):363-366
In a high-volume cytology laboratory in the metropolitan Tokyo area, the incidence of cytologically diagnosed herpes infection in cervical scraping smears of the female genital tract was studied according to the year-by-year changes, age distribution, seasonal variation and types of cytologic alteration. The overall incidence over the 12 years studied was 0.007% (87 cases among 1,230,773 examined). The incidence varied from 0.003% to 0.005% in the early 1970s (except for 1973) and increased to 0.011% in the last three years (1980 to 1982). A large increase was noted in younger age groups in comparison with middle and older age groups. There was a tendency for the infection rate to be higher in the spring (0.011%) and lower in the fall (0.005%). Multinucleation and a ground-glass appearance were observed in the infected cells in almost every case while eosinophilic inclusion bodies were found in 20.7% of the cases. 相似文献
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K Izumi 《Journal of bacteriology》1962,83(5):956-959
Izumi, Kunihiko (Kanazawa University, Kanazawa, Japan). Mucopolysaccharides produced by a strain of Clostridium perfringens. J. Bacteriol. 83:956-959. 1962.-A new series of mucopolysaccharides was isolated from the culture medium of Clostridium perfringens and partially purified by the use of a column of anion-exchange resin. A large part of the substance was composed of neutral sugars, amino sugars, uronic acids, and oligopeptides, suggesting a structure analogous to that of bacterial cell walls. Acidic amino acids, especially aspartic acid, were the main constituents of the oligopeptides. The substance exhibited high viscosity when dissolved in water. The degree of viscosity in each fraction seemed to depend on the content of amino sugars and the chain length of the oligopeptides. 相似文献
20.
Xenobrama microlepis gen. et sp. nov. is described on the basis of 17 adult and subadult specimens collected by surface gill nets, bottom trawl
and midwater trawl from the subantarctic waters of the South Pacific Ocean. This monotypic new genus is distinguished from
other bramid genera by the following characters: inner lower edges of mandible touching each other (except near symphysis);
gill rakers short, thick, and stout; subpectoral region very narrow; interpelvic space flat and wide; vertebrae 49–51; and
scales in longitudinal series more than 83. The new taxon is widely distributed in the high seas of the South Pacific, 38–54°S,
79–176°W, but is rather rare compared toBrama spp. in catches of drift gill nets. 相似文献