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81.
Differentiating Small Round Cell Sarcomas of the Soft Parts by an Innovative Immunogold Labeling Method: An Ultrastructural Study 总被引:1,自引:0,他引:1
A new immunoelectron microscopy procedure was developed by remaking the fixed-frozen tissue specimens into LR White resin blocks suitable for postembedding colloidal gold immunolabeling, and used to examine 16 cases of small round cell soft tissue sarcomas. In rhabdomyosarcoma, ultrastructural double-immunogold staining demonstrated a coexpression of muscle specific actin and desmin in the same tumor cell. In both Ewing's sarcoma and peripheral neuroepithelioma, the heterogeneous expression of MIC2 gene product (p30/32MIC2) in each tumor cell was demonstrated as well. In peripheral neuroepithelioma, the colloidal gold immunolabeling for neurofilament demonstrated the intermediate filaments surrounding microtubules. The procedure for ultrastructural colloidal gold immunolabeling using fixed-frozen tissue is thus considered to be useful not only for tumor diagnosis, but also for investigating various subcellular structures. 相似文献
82.
人胚胎肺内神经内分泌细胞电镜观察 总被引:1,自引:0,他引:1
用透射电镜对不同胎龄的人胚胎肺内神经内分泌细胞进行了发生和超微结构观察。肺内支气管上皮内未分化细胞,第八周开始向神经内分泌细胞转化,提示神经内分泌细胞对早期胚胎肺的发生、发育有特殊意义。神经内分泌细胞内致密核心小泡(DCV)及其它与内分泌活动有关的各种细胞器发达。能见到P0细胞、P1细胞、P2细胞及P3细胞等四种类型的神经内分泌细胞。P0细胞的发生及分化程度表明它可能是一种前细胞,它可以进一步转化 相似文献
83.
G. S. Yakobson S. G. Dobrovol'skaya G. M. Vakulin 《Bulletin of experimental biology and medicine》1978,85(4):502-506
The pattern of injury and repair in the liver of Wistar rats depending on sex, the phase of the estrous cycle, and also under the conditions of deficiency of female sex hormones and after injection of -estradiol into ovariectomized rats was studied by morphometric, histo chemical, and electron-microscopic methods. Structural disturbances caused by CCl4 were found to be increased and reparative reactions inhibited in the liver of females both during the period of a natural increase in the blood estrogen concentration and under the influence of exogenous estradiol, and ovariectomy also had a protective effect. In males, structural changes in the liver were more marked than in females with a low blood estrogen level and differend only a little from those in females during the period of increased secretion of sex steroids.Central Research Laboratory, Novosibirsk Medical Institute. (Presented by Academician of the Academy of Medical Sciences of the USSR V. P. Kaznacheev.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 85, No. 4, pp. 460–464, April, 1978. 相似文献
84.
观察老年大鼠下丘脑视上核腹侧大细胞神经元和弓状核神经元的超微结构,结果显示:老年大鼠视上核腹侧血管加压素(VP)神经元的胞体较成年鼠大,胞质结构比较致密,内含许多核糖体颗粒,粗面内质网分散成小泡状,神经分泌颗粒增多,溶酶体、线粒体、高尔基氏复合体数量都较多.而弓状核内的暗细胞和亮细胞的核糖体减少,高尔基氏复合体和线粒体都变化,还有少数神经元固缩,细胞质内胞器明显减少,呈现变性现象.结果提示:老年期下丘脑视上核VP神经元机能增强;而弓状核内两种细胞都显示机能减弱的征象.老年时下丘脑各核团神经元的这种不协调性变化,可能是动物衰老的一种重要表现. 相似文献
85.
Carlo Capella Luciana Usellini Mauro Papotti Luigia Macri Giovanna Finzi Vincenzo Eusebi Gianni Bussolati 《Ultrastructural pathology》1990,14(4):321-334
The ultrastructural patterns of neuroendocrine (NE) differentiated breast carcinomas are analyzed and discussed. Reports in the literature describe wide variations in the size of observed dense-core membrane-bound granules and discrepancies in their interpretation. In the present study 24 cases of breast carcinoma with recognized morphologic, histochemical, and immunocytochemical features of NE tumors were investigated. Five different types of dense-core granules of neurosecretory (NS) type (confirmed by the ultrastructural localization of chromogranin A) and five different cell types were recognized. Some amphicrine cells were found to contain both mucin and NS granules. Another notable ultrastructural feature of breast NE carcinomas was the presence of clear vesicles of presynaptic type, which correlated with expression of synaptophysin. 相似文献
86.
阿霉素性心肌病之心肌线粒体酶的细胞化学研究 总被引:2,自引:0,他引:2
阿霉素性心肌病之心肌线粒体SDH和CCO的细胞化学观察发现,多数线粒体的酶活性较弱,少数较强或中等,并与ADR的累积用量和心肌损伤程度有关。作者认为SDH和CCO活性降低,线粒体能量代谢障碍在ADR引起心肌病的过程中起着重要作用。 相似文献
87.
Chibisov SM Breus TK Illarionova TS 《Bulletin of experimental biology and medicine》2001,132(6):1150-1153
Magnetic storm modulates morphological and functional state of the heart and the related systems. Changes in cardiomyocyte ultrastructure induced by changes in geomagnetic activity were studied in experiments on rabbits. We describe a possible mechanism underlying changes in cardiac activity in intact animals induced by geomagnetic perturbations. The most pronounced alterations of cardiomyocyte ultrastructure were observed during the major phase of magnetic storm. 相似文献
88.
Paneth cell-rich carcinoma of the stomach 总被引:1,自引:0,他引:1
89.
Jocelyne Fleury-Feith Laurence Kheuang Lin Zeng Jean Bignon Christian Boutin Isabelle Monnet Marie-Claude Jaurand 《The Journal of pathology》1995,177(2):209-215
The aim of this study was to determine, by transmission electron microscopy, the differentiation features of 21 human malignant mesothelioma cell lines (HMCLs) established from 13 specimens of 12 confirmed human malignant mesotheliomas, and of tumours induced in nude mice injected with 16 HMCLs. Fifty per cent of HMCLs showed typical mesothelial differentiation (long and slender microvilli, desmosomes, perinuclear intermediate filaments); 29 per cent did not show differentiation; and the remainder were poorly differentiated. Three human tumour specimens gave several different HMCLs; the cell lines obtained from a given tumour exhibited variable mesothelial differentiation. Eleven HMCLs were compared with the native tumour. Four were similar to the tumour and seven were less well differentiated, in most cases in relation to their microvilli. With six HMCLs, tumours induced in nude mice were less well differentiated than the corresponding cell lines, whereas with four HMCLs, tumours were equally or better differentiated. However, in most nude mice tumours, typical mesothelial microvilli were present. These results show that cell lines established from malignant mesothelioma may exhibit dedifferentiated features. However, while the variability in ultrastructural differentiation may result from the culture microenvironment, it could also be related to the state of differentiation, of the native tumour sample and to tumour cell heterogeneity. 相似文献
90.
G. V. Mardanova V. V. Osipov G. N. Kostryukov 《Bulletin of experimental biology and medicine》1990,109(4):523-527
Department of Mini-Pig Models, Research Laboratory of Experimental Biological Models, Academy of Medical Sciences of the USSR, Krasnogorsk, Moscow Region. (Presented by Academician of the Academy of Medical Sciences of the USSR A. P. Avtsyn.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 109, No. 4, pp. 398–400, April, 1990. 相似文献