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Patients after kidney, heart and lung transplantation differ in their immunosuppressive drug regimens and in susceptibility to infectious complications with cytomegalovirus (CMV). In this study, CMV-specific T-cell responses were characterized in long-term transplant recipients and associated with the frequency of infectious complications. CMV-reactive CD4 T cells from 50 healthy controls, 68 renal, 14 heart and 24 lung transplant recipients were flow cytometrically quantified by the induction of cytokines after specific stimulation. Moreover, the immunosuppressive effect of calcineurin inhibitors on specific T-cell reactivity was quantified in vitro and compared with responses in vivo. Median CMV-specific T-cell frequencies in long-term renal (1.48%; range 0.06-17.26%) and heart transplant recipients (0.90%; 0.13-12.49%) did not differ from controls (1.82%; 0.26-21.00%). In contrast, CMV-specific T-cell levels were significantly lower in lung transplant recipients (0.50%; <0.05-4.98%) and showed a significant correlation with the frequency of infectious episodes (r =-0.57, p = 0.005). The differences within the groups were associated with increasing dosages of immunosuppressive drugs, as exemplified for calcineurin inhibitors that dose dependently reduced specific T-cell reactivity in vitro. In conclusion, monitoring CMV-specific CD4 T cells may serve as a measure for long-term disease susceptibility and may contribute to an improved management of CMV complications after lung transplantation.  相似文献   
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Deck officers on coastal tankers may be exposed to high concentrations of cargo vapors during loading and tank-cleaning operations. Two cases of acute nonlymphatic leukemia are described. Both men had worked as chief officers on coastal tankers transporting benzene and other petroleum products.  相似文献   
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Intravenously injected polystyrene microspheres with functional amino groups (AP-MSs, 0.2,1.0, and 4.0 urn in diameter) were cleared from the blood very rapidly. The calculated half-lives for 0.2-, 1.0-, and 4.0-μm AP-MSs were about 55,60, and 50s; no significant differences were found with 106,107, and 108 microspheres/rat. Loading experiments showed that the liver, spleen, lung, kidney, and heart had a very high capacity to take up AP-MSs. The AP-MSs were distributed mainly to the liver, lung, and spleen, whereas other organs contained less than 1 % of injected AP-MSs. In terms of numbers of AP-MSs per gram of tissue, the highest contents were found in spleen, liver, and lung for 0.2-, 1.0-, and 4.0-um AP-MSs, respectively. There was indication of redistribution of particles from one organ to another during the first 6 h after injection. Chondroitin sulfate A (Chon) and hyaluronic acid (Hya) adsorbed or covalently linked to AP-MSs increased uptake in the liver, with Chon AP-MSs (adsorbed or linked) showing the best effect: about 25% increase compared with unadsorbed 1-μm AP-MSs. Experiments with separated cells in vitro demonstrated that 1 um AP-MSs, intravenously injected, associated only with Kupffer cells. When the microspheres were adsorbed with Chon, there was also association with liver endothelial cells. This finding indicates that conjugation of microspheres with ligands for endothelial receptors may be a useful method for directing microspheres to specific organs, even if the receptors are not by themselves phagocytic  相似文献   
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The purpose of this study was to evaluate an instrument for assessment of physical disability, mainly intended for clinical settings, the Disability Rating Index (DRI). Healthy persons (n = 1092), both white and blue collar workers, and patients (n = 366) with different levels of physical capacity, were assessed. Most of the patients (n = 303) underwent rehabilitation programmes for neck/shoulder/low-back pain but some (n = 47) were arthritis patients waiting for hip or knee replacement surgery, or wheelchair patients with multiple sclerosis (n = 16). The reliability was investigated by test-retest studies, intra- and inter-rater and internal consistency studies. Five construct validity tests were carried out: a discrimination study; a converging validity test; a test for sensitivity to small alterations in health status; and two correlational validity tests. Correlation of the self-reported DRI to the actual performance in similar activities was carried out. Responsiveness was tested by correlation of the DRI before/after replacement surgery for arthritis. The test-retest correlations were 0.83–0.95 in the studies, including correlation of different versions. The intra- and inter-rater reproducibility was 0.98 and 0.99 respectively. The Kruskal-Wallis test in the discrimination study yielded p < 0.0001. More than 90% of the respondents completed the questionnaire correctly. Correlation of the DRI to the Functional Status Questionnaire was 0.46. The responsiveness was excellent, p = 0.0001. The DRI proved to be a robust, practical clinical and research instrument with good responsiveness and acceptability for assessment of disability caused by impairment of common motor functions.  相似文献   
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