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991.
Ron D.M. Soede Yvonne M. Wijnands Ioana Van Kouteren-Cobzaru Ed Roos 《The Journal of cell biology》1998,142(5):1371-1379
The ZAP-70 tyrosine kinase is essential for T cell activation by the T cell receptor. We show that ZAP-70 is also required for migration of T cells that is dependent on the integrin LFA-1. Invasion of TAM2D2 T cell hybridoma cells into fibroblast monolayers, which is LFA-1–dependent, was blocked by overexpression of dominant-negative ZAP-70 and by piceatannol but not by herbimycin A. The Syk inhibitor piceatannol blocks the Syk homologue ZAP-70, which is expressed by TAM2D2 cells, with the same dose dependence as the inhibition of invasion. Dominant-negative ZAP-70 completely inhibited the extensive metastasis formation of TAM2D2 cells to multiple organs upon i.v. injection into mice. Migration of TAM2D2 cells through filters coated with the LFA-1 ligand ICAM-1, induced by 1 ng/ml of the chemokine SDF-1, was blocked by anti–LFA-1 mAb and also abrogated by dominant-negative ZAP-70 and piceatannol. In contrast, migration induced by 100 ng/ml SDF-1 was independent of both LFA-1 and ZAP-70. LFA-1 cross-linking induced tyrosine phosphorylation, which was blocked by dominant-negative ZAP-70 and piceatannol. We conclude that LFA-1 engagement triggers ZAP-70 activity that is essential for LFA-1–dependent migration. 相似文献
992.
993.
Dr. Ed. Formánek 《Plant Systematics and Evolution》1885,35(8):265-270
Ohne Zusammenfassung 相似文献
994.
Dr. Ed. Formánek 《Plant Systematics and Evolution》1885,35(5):153-160
Ohne Zusammenfassung 相似文献
995.
A. Papas D.M.D. Ph.D. J. Herman D.M.D. C. Palmer M.Ed. R.D. M. Rounds M.Ed. R.D.H. R. Russell M.D. R. McGandy M.D. M.P.H. S. Hartz Sc.D. R. Jacob Ph.D. R. Feldman D.D.S. D.M.Sc 《Gerodontology》1984,3(2):147-155
This paper is a preliminary report of a dental pilot study which was recently conducted with 104 elderly subjects, 77 of whom also participated in a nutrition status survey. The study was comprehensive, including measurements of oral health status, and medical data concerning nutrition status. Also included were questionnaires concerning diet and nutritional habits, and attitudes towards dental care. A literature review is also presented. Statistical analysis reveals correlations between certain food types, (liquid/solid fermentable, slowly dissolving fermentable), and root and coronal decay. The correlation with coronal decay is greater. Some of the data are still undergoing analysis. When all the data are analyzed and available, additional reports will be forthcoming and will describe any other correlations that are found between nutritional and oral health status. Certain new periodontal indices will also be described. The relationships between the oral health status and the nutritional needs of the elderly have not been adequately studied. It is expected that with a broader data base, these relationships will be better understood. 相似文献
996.