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Apoptotic cells, e.g. postinflammatory neutrophils, were reported to be engulfed by phagocytes without induction of an inflammatory response. We investigated the humoral immune response of BALB/c mice after repeated injection of viable or apoptotic human T cells. Following interleukin-2 (IL-2) deprivation, phytohaemagglutinin (PHA)/IL-2 expanded human T-cell lines were irradiated with UV-B light to induce apoptosis, confirmed by propidium iodide staining of Triton X-100-lysed cells. Indirect immunofluorescence was used to detect antilymphocyte antibodies 7 days after each injection. We found high levels of antilymphocyte antibodies in all animals immunized with viable T cells, whereas animals injected with apoptotic cells showed a significantly reduced humoral immune response. We conclude that apoptotic cells induce poor xenoreactive T-cell responses when compared with viable cells.  相似文献   
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PURPOSE: To compare tests for intestinal function with clinical scores after abdominal irradiation. PATIENTS AND METHODS: At the Department of Radiotherapy, Erfurt, Germany, intestinal changes were studied in 91 patients receiving abdominal radiotherapy between 1992 and 1996. Conventional fractionation (1.8-2 Gy per fraction, total doses 30.6-62.5 Gy) was applied. Before and at weekly intervals during radiotherapy, the clinical response was scored according to RTOG/EORTC for the upper and lower gastrointestinal (GI) tract. Resorption tests for vitamin B(12) and D-xylose were performed before the onset and immediately after treatment. RESULTS: The clinical response displayed a well-defined dose-effect relationship with grade 1 effects in 5% and 50% of the patients at about 10 Gy and 50 Gy, respectively. For grade 2 reactions, 5%- and 50%-effective doses were 20-30 Gy and 60-80 Gy. Effects in the upper and lower GI tract were highly correlated. Changes in body weight did not show a correlation with other clinical symptoms. Changes in resorption also displayed a significant dose effect. However, no correlation was found with the clinical symptoms in the individual patient. CONCLUSION: In the present study, the clinical manifestation of intestinal side effects according to RTOG/EORTC criteria was reflected by neither the vitamin B(12) nor by the D-xylose resorption test. Hence, these tests cannot be regarded as useful for objective quantitation of intestinal radiation injury.  相似文献   
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Information on the relative incidence of Crohn's disease and ulcerative colitis was obtained by a prospective investigation at six Melbourne teaching hospitals. One hundred and eleven patients who presented with chronic inflammatory bowel diseases between 1980-1981 were admitted to the study. Forty (36%) patients were diagnosed as having Crohn's disease and 63 (57%) patients as having ulcerative colitis. The type of chronic inflammatory bowel disease could not be determined in eight (7%) patients. These findings suggest that the relative frequency of Crohn's disease and ulcerative colitis in Melbourne hospitals is within the range that is reported for northern Europe and the United States.  相似文献   
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The development of in vitro blood tests that measure the delayed hypersensitivity reaction developed after contact with Mycobacterium tuberculosis will change progressively the diagnosis of M. tuberculosis infection. These blood assays (Quantiferon TB Gold, Cellestis, Australia; T-SPOT.TB, Oxford Immunotec, United Kingdom) use specific, complex M. tuberculosis antigens (ESAT-6 and CFP-10), whereas the intra-dermal Mantoux test is done with tuberculin, a complex mixture of more than 200 antigens. ESAT-6 and CFP-10 are absent from all the BCG vaccine strains used throughout the world. Significant improvement in the specificity with equivalent or increased sensitivity of the in vitro tests compared to the Mantoux test will lead eventually to replacement of the latter.  相似文献   
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