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991.
L László J Tuckwell T Self J Lowe M Landon S Smith J N Hawthorne R J Mayer 《The Journal of pathology》1991,164(3):203-214
Immunofluorescence studies on Epstein-Barr virus (EBV)-transformed lymphoblastoid cells have previously shown that the latent membrane transforming protein (LMP-1) is found in patch-like inclusions which also immunostain for vimentin. We now show that EBV transformation causes a major reorganization of intermediate filaments, microtubules, mitochondria, and lysosomal elements, which generally become oriented around the microtubule organizing centre. Immunogold electron microscopy shows that LMP-1 is primarily concentrated in secondary lysosomes together with ubiquitin-protein conjugates and heat-shock protein 70. Intermediate filament inclusion formation with the above characteristics may be a general response triggered by other membrane glycoproteins; as seen, for example, in major human neurodegenerative diseases such as diffuse Lewy body disease. 相似文献
992.
This article reports on the experience with 38 biopsies from nasal mucosa, submitted with the question of immotile cilia syndrome. Fixation in glutaraldehyde with MgSO4 is preferable. At least 50 cilia should be scrutinized in the electron microscope, and dynein arms, radial spokes, sheaths, nexin links and orientation should be tabulated. Six cases displayed virtual absence of inner and outer dynein arms. The orientation of these cilia was random. Two of the patients had situs inversus. In biopsies considered not to represent the immotile cilia syndrome, about four inner and seven outer dynein arms were found per cilium. 相似文献
993.
994.
Two cases of acute Wernicke's encephalopathy with severe hypothermia as the major presenting feature are reported. Treatment with thiamine was rapidly introduced, but hypothermia nevertheless persisted for several weeks, at times masked by intercurrent infections. 相似文献
995.
Natural killer activity of human blood lymphocytes 总被引:1,自引:0,他引:1
Natural killer (NK) activity is an operational designation. It implies the in vitro cytotoxicities registered in short-term tests exerted by lymphocytes derived from donors with no known immunization history against the particular target. The strength of the effect exerted by unmanipulated blood lymphocytes shows an individual variation. Short-term in vitro treatment with interferon elevates the lytic potential of lymphocytes. Owing to the heterogeneity of the cytotoxic blood lymphocytes with regard of cell surface properties it is not possible to separate all active cells and inactive cells in clean populations. A considerable enrichment of active cells can be achieved if nylon wool non-adherent, large, granular Fc gamma receptor positive SRBC receptor negative--or low-avidity SRBC receptor positive--OKM1-reactive cells are separated. Negative cells are concentrated in the Fc receptor and OKM1-negative high-avidity SRBC receptor positive high cell density subset. The activity of lymphocytes in the former category is potentiated by interferon and the latter acquire the lytic function if PHA is added to the assay system. Freshly separated, non-cultured tumor cells are not or weakly sensitive to the effect of unmanipulated lymphocytes. However, when the lymphocytes are treated with interferon prior to the assay a lytic potential can be induced even against these in allogeneic effector target combinations. Cytotoxic cells which acquired the function after in vivo and/or in vitro immunization are designated as 'cytotoxic T-lymphocytes' (CTL), and were shown to act on the basis of antigen recognition. The expression of known T-markers on at least a fraction of the active cells and the recognition of alloantigens in NK systems suggest that the distinction between CTL and NK cells is not as sharp as initially suggested. 相似文献
996.
Constitutional t(15;17) 总被引:2,自引:0,他引:2
997.
Autonomic and peripheral nerve functions as well as the possible short-term effect of a novel aldose reductase inhibitor (ARI) on neuropathy were evaluated in 30 male type I diabetics (age 25-44 years, mean 34; duration of diabetes 10-20 years, mean 34) with neurographic signs of peripheral neuropathy (PN). Autonomic neuropathy (AN) was established by the heart rate reactions to deep breathing (E/I ratio = vagal function) and to tilt (acceleration index = sympathetic and vagal functions; the brake index = vagal function). Twenty-nine patients, 13 with AN, completed the study. Among neurographic variables, only sural nerve function tests correlated with autonomic functions. Patients with AN showed significantly lower mean sensory action potential amplitudes (SAPA) sural, indicating axonal losses, than patients without AN (3.58 +/- 0.79 microV v. 7.34 +/- 1.12 microV; p less than 0.01). PN as measured by neurography did not improve during ARI treatment. On the other hand, vagal function (brake indices) improved (p less than 0.05) during ARI in AN patients. 相似文献
998.
Fluid was collected from cysts ofTaenia hydatigena in 60 adult sheep and fluid from each animal pooled separately. By double diffusion antigen 5 was demonstrated in all pools but one. The criteria are described for selection and standardization of these preparations for use as antigens for the immunodiagnosis of human hydatid disease. Sera from 50 persons harbouring hydatid cysts and from 50 patients with other disease conditions were examined by the arc-5 double-diffusion test, using two antigens prepared fromEchinococcus granulosus andT. hydatigena cyst fluids, respectively. The results showed that a higher diagnostic sensitivity was obtained with the hydatid antigen. The significance of the findings is discussed in terms of their application to human immunodiagnosis in areas where hydatidosis, but not cysticercosis, is rare in livestock. 相似文献
999.
John David N. Dionisio Alfonso F. Cárdenas PhD Robert B. Lufkin Antonio DeSalles Keith L. Black Ricky K. Taira Wesley W. Chu 《Journal of digital imaging》1997,10(1):21-26
A prototype multimedia medical database is described for supporting thermal ablation therapy of brain tumors. Its design is motivated by the major need to manage and access multimedia information on the progress and reaction of tumors to various therapy protocols. The database links images to patient data in a way that permits the user to view and query medical information using alphanumeric, temporal, and feature-based predicates. Visualization programs permit the user to view or annotate the query results in various ways. These results support the wide variety of data types and presentation methods required by neuroradiologists to manage thermal ablation therapy data. The database satisfactorily meets the requirements defined by thermal ablation therapy. A similar approach is being undertaken for supporting different therapies of other types of tumors, thus showing the generality of our approach. 相似文献
1000.
Experimental Escherichia coli ascending pyelonephritis in rats: changes in bacterial properties and the immune response to surface antigens. 下载免费PDF全文
I Mattsby-Baltzer L A Hanson B Kaijser P Larsson S Olling C Svanborg-Edén 《Infection and immunity》1982,35(2):639-646
Systemic and urinary antibody responses were examined in rats with experimental ascending pyelonephritis caused by Escherichia coli O6K13H1. During 12-month follow-up of the infections, bacterial characteristics of the urinary and renal isolates were followed: O and K antigenicity, sensitivity to the bactericidal effect of normal human serum, capacity to attach to urinary tract epithelial cells, hemolytic activity, biochemical pattern, and virulence. During the long-term infection, the urinary and renal bacterial isolates changed in O and K antigenicity, serum sensitivity, and virulence. The adhesive capacity of the bacterial isolates did not change, possibly explaining the persistence of the bacteria in the urinary tract. The serum anti-O6 antibody levels remained high during the entire 1-year observation period, especially in the rats with renal involvement. Urinary anti-O6 antibodies were also found. The serum and urinary antibodies could have played a role in bringing about the observed changes in bacterial characteristics. Antibodies to lipid A were recorded in 9 of 16 rats with pyelonephritis and renal scarring and in 1 of 9 rats not having pyelonephritis or renal bacterial growth. 相似文献