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31.
Jacques R. Caldwell David E. Pearce Craig Spencer Rosmarie Leder Robert H. Waldman 《The Journal of allergy and clinical immunology》1973,52(4):225-230
Immunologic studies were performed on 5 patients with pigeon breeders' disease. Intradermal injection of pigeon serum produced an immediate wheal-and-flare reaction within 15 minutes and a secondary Arthus-type reaction within 4 to 8 hours. Immunofluorescent studies of the secondary reaction site showed IgG, C3, and C4 in 2 patients. Patients' sera produced multiple precipitin bands with pigeon serum when reacted by double diffusion in gel. IgG antibody isolated from each of the patients' serum formed precipitating immune complexes that fixed large amounts of complement (C4) when added to fresh human serum. Peripheral blood lymphocytes from 4 of the 5 patients produced macrophage migration inhibitory factor (MIF) when challenged with dilute pigeon serum. These studies are the first to show complement fixing antibodies and macrophage MIF production by lymphocytes from patients with hypersensitivity lung disease and suggest that both humoral and cellular immunity may be important in the pathogenesis of these disorders. 相似文献
32.
R.S.K. Chaganti Roller B. Bailey Suresh C. Jhanwar Zalmen A. Arlin Bayard D. Clarkson 《Cancer Genetics and Cytogenetics》1982,5(3):215-221
Malignancy in patients with constitutional chromosome abnormality is of interest not only because it permits insights into the relationship between chromosome abnormality and cancer, but also because it provides opportunities to address such questions as the clonality and evolution of tumors. We report Ph1-positive chronic myelogenous leukemia (CML) in a 50-year-old mosaic (45,X/46,XX) Turner syndrome patient whose leukemia was restricted to the monosomic cell line. Our extensive cytogenetic studies of this patient demonstrated that non-leukemic normal cells persisted in the marrow and were able to proliferate during a period of temporary suppression of the leukemic clone following aggressive treatment. 相似文献
33.
Functional mapping of the activity of the R region in the human T-cell leukemia virus type I long terminal repeat to increase gene expression 总被引:3,自引:0,他引:3
We previously demonstrated the activity of the R fragment in the long terminal repeat of human T-cell leukemia virus type I for elevation of the level of gene expression. In this study, the fragment was deleted with BAL31 nuclease to determine its functional domain. Series of the shortened R fragments were linked to the simian virus 40 promoter unit, which regulated expression of a reporter gene. Examination with the R fragments deleted from the 5 and 3 ends showed that borders of the functional domain were mapped within nucleotide positions 458 to 473 for the 5 end and nucleotide positions 559 to 594 for the 3 end, respectively. Thus we conclude that a 136-base-pair fragment corresponding to the second half of the R region was sufficient to allow elevation of the level of gene expression. 相似文献
34.
采用半固体一步单层琼脂培养法和单克隆荧光抗体技术分别观察重症肝炎外周血TL-CFU和mIL-2R,发现重症肝炎患者TL-CFU(104.4±32.6)及mIL-2R(35.6±8.6)较正常人明显降低。在培养体系中加胎肝细胞质液后,无论在重症肝炎组还是在正常组均不能明显地提高TL-CFU,说明胎肝细胞质液不含具生物佐的促TL-CFU因子。但对mIL-2R表达的影响,在重症肝炎组病人,只有在PHA存在条件下才能促进mIL-2R的表达,说明胎肝细胞质波含有某种(些)物质能协同PHA促进重症肝炎患者外周血淋巴细胞mIL-2R表达。 相似文献
35.
Chemically induced mutants of an I-Ak,d expressing antigen-presenting B-cell--B-lymphoma hybridoma have recently been generated by immunoselection in vitro and were found to possess alterations in some of their serologically and functionally defined I-Ak region dependent functions. In order to identify at the structural level the origin of the differences in serological and functional properties of these mutants, I-Ak molecules from several of these mutant hybridomas were compared biochemically to wild-type I-Ak polypeptides by two-dimensional gel electrophoresis and high-pressure liquid chromatographic tryptic peptide analyses. Two-dimensional gel electrophoresis indicated that no major structural alterations, resulting in changes in mol. wt or charge, had occurred in the Ak alpha or Ak beta polypeptides from the mutant cells. Likewise, Ak alpha peptide maps of the mutants were indistinguishable from the normal Ak alpha peptide maps. However, two of the three mutants studied did exhibit one additional peptide in their Ak beta peptide maps. These results suggest that the major deficiencies in T-cell-activating functions of these mutants are a result of a limited alteration in the Ak beta polypeptide primary structure. 相似文献
36.
The present study was designed to investigate the relationship between intra-and inter-individual differences in arousal level and performance on both critical flicker fusion frequency and figural reversal tasks. Forty male undergraduate Ss were used. Electrical skin conductance was used as the indicant of arousal level. For the intra-individual comparisons white noise was used to increase the Ss’arousal levels. Significant inverted U-shaped relationships were found between both flicker fusion thresholds and rates of figural reversal and skin conductance between individuals. A significant curvilinear relationship was found between rates of figural reversal and level of conductance within individuals. No significant curvilinear relationship was found between flicker fusion thresholds and level of conductance within individuals. 相似文献
37.
Alyce C. Russell Agnieszka Kepka Irena Trbojević-Akmačić Ivo Ugrina Manshu Song Jennie Hui Michael Hunter Simon M. Laws Gordan Lauc Wei Wang 《Immunobiology》2019,224(1):110-115
Background
Increased body fat may be associated with an increased risk of developing an underlying pro-inflammatory state, thus leading to greater risk of developing certain chronic conditions. Immunoglobulin G has the ability to exert both anti- and pro-inflammatory effects, and the N-glycosylation of the fragment crystallisable portion is involved in mediating this process. Body mass index, a rudimentary yet gold standard indication for body fat, has been shown to be associated with agalactosylated immunoglobulin G N-glycans.Aim
We aimed to determine the association between increased body fat and the immunoglobulin G glycosylation features, comparing body mass index to other measures of body fat distribution.Methods
We investigated a sample of 637 community-based 45–69?year olds, with mixed phenotypes, residing in Busselton, Western Australia. Body mass index and the waist-to-hip and waist-to-height ratios were calculated using anthropometry, while dual-energy x-ray absorptiometry was performed to gain an accurate measure of total and area specific body fat. Serum immunoglobulin GN-glycans were analysed by ultra-performance liquid chromatography.Results
Twenty-two N-glycan peaks were found to be associated with at least one of the fat measures. While the previous association of body mass index to agalactosylated immunoglobulin G was replicated, measures of central adiposity explained the most variation in the immunoglobulin G glycome.Conclusion
Central adiposity is associated with an increased pro-inflammatory fraction of immunoglobulin G, suggesting that the android/gynoid ratio or waist-to-height ratio instead be considered when controlling for adiposity in immunoglobulin G glycome biomarker studies. 相似文献38.
A simple visual observation system, supplemented by measurement of skin potential, was devised for developmental studies of sleep cycles in settings where multiple electrode placement is not practicable. The findings replicated essential features of quiet and active sleep cycles which had been reported previously to exist against the background of decreasing level of physiological arousal, as sleep proceeds. Twelve newborns showed approximately one-half of their inter-feeding sleeping time in the rapid eye movement stage of sleep. Skin potential rapidly declined from the waking level, continued to decrease in level throughout sleep, increased in variability during REM sleep, and increased in level at the second waking period. 相似文献
39.
In the event of smallpox bioterrorism, widespread vaccination may be required. Vaccinia immune globulin (VIG) has been used to treat complications from the smallpox vaccine. While the potency of VIG was defined by its ability to neutralize intracellular mature virus, a second form of vaccinia called the extracellular enveloped virus (EEV) is critical for virus spread in the host. The B5R-protein is one of many EEV-specific proteins. Immunoprecipitation and ELISA revealed that VIG recognizes the B5R-protein. An EEV plaque-reduction assay using a recombinant vaccinia that lacks the majority of the extracellular domain of B5R showed that the ability of VIG to neutralize EEV is principally directed at B5R. In addition, absorbing out the anti-B5R antibody present in VIG through the addition of recombinant B5R protein abrogated VIG's ability to significantly neutralize wild-type EEV. This work demonstrates the prominent role of B5R as a target of EEV-neutralizing activity of human antibodies. 相似文献
40.