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991.
Summary The apical cell coat of the olfactory epithelium proper and the vomeronasal neuroepithelium of the rat was investigated electronmicroscopically by means of the Ruthenium-red reaction. In the olfactory epithelium proper, the cilia of receptor cells and microvilli of supporting cells possess a cell coat measuring approximately 10 nm in thickness. In the vomeronasal neuroepithelium, the apical cell coat is thicker than in the olfactory epithelium proper. On microvilli of vomeronasal receptor cells the cell coat varies in thickness from 15 to 20 nm, and on microvilli of supporting cells it measures approximately 75 nm. The functional implications of these findings are discussed.A portion of this study was presented at the 6th European Anatomical Congress in Hamburg. This publication is dedicated to Prof. E. KlikaSupported by the Deutsche Forschungsgemeinschaft (Br 358/5-1). 相似文献
992.
Lambda Ig constant region genes are translocated to chromosome 8 in Burkitt''s lymphoma with t(8;22) 总被引:11,自引:4,他引:7 下载免费PDF全文
A de la Chapelle G Lenoir J Boué A Boué P Gallano C Huerre M F Szajnert M Jeanpierre J M Lalouel J C Kaplan 《Nucleic acids research》1983,11(4):1133-1142
By in situ hybridization of normal human chromosomes with a cloned genomic probe specific for the constant region of the lambda immunoglobulin genes, band 22q11 was preferentially labelled. In two cell lines with t(8;22) derived from Burkitt's lymphoma a strong signal was noted on the 8q+ chromosome derivative, indicating that the constant region of the lambda Ig gene cluster was translocated from chromosome 22 to chromosome 8. In addition, the signal observed on the 22q- derivative chromosome was stronger than the background in one of the two cell lines tested, but not in the other. The implications are that the break point in chromosome 22 in some cases lies within the Ig gene itself or between clusters of such genes, and that different cases have different break points. 相似文献
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Lysogenic conversion in the Shigella flexneri group 总被引:1,自引:0,他引:1
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An ATPase reaction has been studied at the surface of intact normal and neoplastic human cells in culture. For this purpose a sensitive method has been developed which permits repeated monitoring of enzyme activity without interference with cellular viability. Experiments could be performed with the cells cultured in a single dish. The cells were firmly attached to the supporting medium throughout the experiment. The incubation medium could easily be separated from the cells at the end of the reaction. There was no diffusion of the surface-located ATPase into the incubation medium. Another advantage was the possibility of microscopic control of the appearance of the cells during the reaction. High ATPase activity was found in glia-like cells derived from normal adult brain cells while lines from gliomas had very low activity. One SV40 transformed glia line had an extremely low ATPase activity in contrast to the uninfected cells. Normal fibroblasts and sarcoma cells had about the same low activity as the glioma cells. 相似文献
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Herpes virus aotus: a latent herpesvirus from owl monkeys (Aotus trivirgatus) isolation and characterization 总被引:3,自引:0,他引:3