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991.
AD Struthers 《Canadian Metallurgical Quarterly》1996,17(11):1617-1618
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Intranasal administration of protein antigen is an efficient way to induce mucosal tolerance. Suppressive mechanisms that might be involved in this phenomenon include down-regulation of T-helper type-1 (Th1)-mediated processes by Th2 cells. However, since Th2 responses can also be subjected to mucosal tolerance, we wanted to investigate whether suppression of a typical Th1 response, such as a delayed-type hypersensitivity (DTH) reaction by intranasal tolerance induction, was causally related to up-regulation of Th2 responses. We therefore treated mice either systemically or locally with anti-interleukin-4 (IL-4) or anti-IL-10 antibodies before intranasal tolerance induction or before sensitization for DTH to see whether we could prevent or abrogate tolerance. Although the up-regulation of antigen-specific IgE levels in tolerant mice could be prevented by anti-IL-4 treatment, the extent of tolerance as measured by suppression of DTH was not affected. We therefore conclude that up-regulation of Th2 responses observed after intranasal tolerance induction is an additional or consequential rather than a necessary reaction. 相似文献
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HF L?hr C Elste HP Dienes G Michel HB Braun KH Meyer zum Büschenfelde G Gerken 《Canadian Metallurgical Quarterly》1996,25(3):292-300
BACKGROUND/AIM: Virus-host interactions may have pathogenetic significance in chronic hepatitis. Thus the humoral immune response was evaluated during the clinical course of HCV-infected patients. METHODS: Eighteen selected chronic HCV patients received three doses of 3 or 6 MU interferon-alpha 2a weekly for 6 to 12 months and were followed up for 6 to 60 months. Anti-HCV antibody levels were serially measured either in end-point diluted sera with the Matrix-Assay or with quantitative anti-HC34-IgG and -IgM ELISA. Circulating immune complexes were assessed by flow cytometry and the results were correlated with histology, quantitative HCV-RNA levels and genotypes. RESULTS: Nine complete responders (CR; genotypes 1a n = 4; 1b n = 1; 2a n = 1; 3a n = 3) showing sustained virus elimination and ALT normalisation had low HCV-RNA pretreatment levels (mean 14 x 10(3) copies/ml) compared to six nonresponders and three partial responders (NR/PR; genotypes 1a n = 2; 1b n = 7) who had significantly higher HCV-RNA pretreatment levels (mean 254 x 10(3) copies/ml; p < 0.01). In untreated NR/PR the HC34 core-antigen was most immunogenic, in CR the NS3-derived HC29-antigen. Pre-treatment levels of anti-HC 34-IgG and -IgM antibody levels in NR/PR were higher than in CR (IgM/IgG p = 0.05, n.s.) and these differences became significant during or after therapy (3 months therapy: IgM p < 0.02/IgG p < 0.07; end of therapy: IgM 0.006/IgG p < 0.04; 6 months post-therapy: IgM p < 0.002/IgG p < 0.004). The PR patients showed recurrent anti-HC34 antibody levels that preceded disease reactivation and detectable HCV-RNA in serum. Immune complex formation increased in some patients during treatment but did not correlate with disease activity, quantitative viraemia, antibody levels or therapy outcome. CONCLUSION: Anti-HC34 antibodies, i.e. of the IgM-subtype, correlated quantitatively with viraemia and disease activity. Monitoring the antibody levels may predict the long-term therapy outcome during interferon-alpha treatment. 相似文献
998.
TP Duprez M Gille BC Vande Berg J Malghem CB Grandin P Michel S Ghariani BE Maldague 《Canadian Metallurgical Quarterly》1996,38(6):511-515
Low back pain is caused by a variety of etiologies. Some clinicians have postulated that much low back pain is due to trauma to the iliolumbar ligament. The iliolumbar ligament is one of the three pelvic-lumbar ligaments and develops during the 12th week of gestation. The iliolumbar ligament appears to be a major stabilizing component between the vertebral spine and the pelvis. The innervation of the iliolumbar ligament appears similar to the posterior lumbar ligaments. Our hypothesis is: micro-trauma to the iliolumbar ligament is the primary cause of many cases of chronic low back pain because (1) it is the weakest component of the multifidus triangle; (2) there is increased susceptibility to injury due to its angulated attachment; (3) it is a primary inhibitor of excess sacral flexion; (4) it is a highly innervated nociceptive tissue; and (5) it plays an increased role with progressive disc degeneration. 相似文献
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ME Kuipers PJ Swart M Schutten C Smit JH Proost AD Osterhaus DK Meijer 《Canadian Metallurgical Quarterly》1997,33(2):99-108
Changes of blood metabolites and hormones were studied in female breeding calves before, during and after weaning from 4 to 18 weeks of age. Calves were initially fed increasing amounts of whole milk (up to 7 kg/day in week 8 of life). Milk intake was then gradually decreased up to the age of 16 weeks, when calves were completely weaned and only fed hay and concentrates. Average daily gain was 0.85 kg. Postprandial concentrations of glucose, insulin, insulin-like growth factor-I and 3.5.3'-triiodothyronine concentrations gradually decreased (P < 0.05) with age, while those of beta-hydroxybutyrate, protein, albumin, haemoglobin and iron increased (P < 0.05). Concentrations of cholesterol transiently increased, whereas those of urea reversibly decreased. Non-esterified fatty acids, triglycerides and growth hormone did not consistently change during the duration of the study. In conclusion, changes of glucose, beta-hydroxybutyrate, haemoglobin, iron, insulin, insulin-like growth factor-I and 3.5.3'-triiodothyronine were markedly different from those usually seen in veal calves of the same age. 相似文献