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631.
HLA-DR expression on keratinocytes is a common feature of diseased skin   总被引:5,自引:1,他引:5  
Biopsy specimens from 185 patients with 52 different skin disorders were investigated by indirect immunofluorescence staining for the presence of HLA-DR bearing keratinocytes and their association with an underlying inflammatory infiltrate and in particular with activated (HLA-DR-positive, Leu-4-positive) T lymphocytes. HLA-DR expression on keratinocytes was demonstrated in 38 dermatoses, including lymphocytic vasculitis, lupus erythematosus, morphea, vitiligo, lichen planus, cutaneous T-cell lymphoma, various infectious dermatoses, allergic contact dermatitis, granulomatous dermatoses, Sweet's syndrome, lichen sclerosus and erythema nodosum. In 27 of these this had not previously been reported. Occurrence of HLA-DR on keratinocytes was invariably linked to the presence of a lymphocytic infiltrate containing numerous activated T-cells (Leu-4 +, HLA-DR +) whereas such infiltrates were not accompanied by HLA-DR expression on keratinocytes in all the dermatoses investigated, as in pseudolymphoma and erythema anulare centrifugum. However, HLA-DR positive keratinocytes were consistently absent in skin disorders lacking any significant lymphocytic infiltration (e.g. leukocytoclastic vasculitis, bullous autoimmune dermatoses, genodermatoses and mastocytosis). Although it has been suggested that HLA-DR-positive keratinocytes are involved in various immune responses of the skin, their exact functional significance is, as yet, unknown.  相似文献   
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Thirteen subjects who had normal knees and fifteen patients who had a chronic rupture of the anterior cruciate ligament were tested in order to compare the measurements of tibiofemoral displacement as recorded by four commercial devices: the Acufex knee-signature system, the Genucom knee-analysis system, the Medmetric KT-1000 arthrometer, and the Stryker knee-laxity tester. Anterior and posterior displacement were measured at forces of eighty-nine newtons (twenty pounds) and 133 newtons (thirty pounds). We found significant differences in reproducibility of measurement among the devices. The Acufex, Medmetric, and Stryker devices had more reproducible measurements, and they could be used to identify 80 to 90 per cent of the normal subjects and anterior cruciate-deficient patients. The Genucom device had poorer reproducibility of measurement, and it tended to register greater differences in displacement between the right and left knees of normal subjects.  相似文献   
634.
Allergic sensitization and symptoms from the airways in relation to air pollution were compared in 10–12-year-old school children (n= 1113) from urban Konin in central Poland and both urban and rural parts of Sundsvall in northern Sweden. The measurements included parental questionnaires, skin-prick tests and serial peak flow measurements during 2 weeks with simultaneous monitoring of outdoor air pollutants. The skin-prick test technique was validated by IgE antibody determinations. The levels of common industrial pollutants, SO2 and smoke particles were much higher in Konin than in urban Sundsvall and the levels of NO2 were similar. Various respiratory symptoms were more often reported among school children in Konin (except for wheezing and diagnosed asthma). Multiple logistic regression analyses yielded the following increased odds ratios for children in Konin as compared with the reference group (rural Sundsvall): chest tightness and breathlessness 348 (95% confidence interval 2.08–5.82), exercise-induced coughing attacks 3.69 (95% confidence interval 1.68–8.10), recurrent episodes of common cold 2.79 (95% confidence interval 1.53–5.09) and prolonged cough 4–89 (95% confidence interval 2.59–9.23). In contrast, as compared with rural Sundsvall, the adjusted odds ratio for a positive skin-prick test was decreased in Konin, but increased in urban Sundsvall, 0.58 (95% confidence interval 0.37–0.91) and 1.67 (95% confidence interval 1.15–2.42) respectively. The study confirms that living in urban, as compared with rural areas, is associated with an increased prevalence of respiratory symptoms and sensitization to allergens. These differences could be explained by air pollution. Respiratory symptoms were more common in a similar urban group of Polish children who were exposed to even higher levels of air pollution. These children, however, had a much lower prevalence of sensitization to allergens, as compared with the Swedish children. This indicates that differences in lifestyle and standard of living between western Europe and a former socialist country influences the prevalence of atopy.  相似文献   
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Cytomegalovirus (CMV) infection is one of the most important causes of morbidity and mortality in solid organ transplantation. It can present with hematuria, the most common urological complication in the early post-simultaneous pancreas-kidney (SPK) transplant period. In SPK transplantation, CMV infection usually occurs 1 month after transplantation. We report an instance of bladder-drained SPK transplant presenting with recurrent gross hematuria from CMV infected duodenal graft ulcers 15 years after preserved well-functioning grafts. Serum quantitative Polymerase Chain Reaction (qPCR) for CMV was negative. Postmortem duodenal graft staining for CMV was positive, and revealed the cause of the inciting ulcer. To our knowledge, our patient is the first reported case of very late onset invasive CMV disease causing duodenal graft ulcers 15 years after transplantation, as previously reported cases of posttransplant CMV disease occurred only as late as 18 months. In addition, the absence of correlation between CMV viremia and CMV-infected duodenal allograft in SPK transplant has not been reported. Our case demonstrates that CMV viral load is -unreliable to diagnose invasive CMV disease, and tissue biopsy should be obtained to avoid missed diagnosis causing high morbidity and mortality.  相似文献   
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