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991.
Eleven children with Pseudomonas aeruginosa infection complicating foot puncture wounds were reviewed. Delay in presentation (mean 2 days) and diagnosis (mean 9 days) due to a paucity of clinical signs of deep infection was characteristic of this condition. Septic arthritis (5 patients) and osteomyelitis (3 patients) were frequent complications. Treatment involved multiple surgical debridements and prolonged intravenous antibiotic therapy. The clinical outcome was good although long-term radiographic changes were common.  相似文献   
992.
The impact of a cancer diagnosis upon a family has become a focus of clinical interest, but few scientific studies have been completed in this area. The objectives of this pilot study were twofold: first, to test the applicability of the Family System Test (FAST) in families (n=5) with a young adult member with cancer and secondly to evaluate patterns of interactions within these families. Results show that the FAST is applicable and useful to evaluate the different perceptions of hierarchy and cohesion - two essential variables - within these families. The great majority of family members represented their relationships as balanced (i.e., cohesive and moderately hierarchical). However, contrary to nonclinical families, fathers had a less positive view than mothers and patients: fathers more often perceived family and parenteral relations as unbalanced, and also more often perceived a reversal of hierarchy and a cross-generational coalition within the family. Implications for future research and clinical care are discussed.  相似文献   
993.
Deep granuloma annulare (DGA) is one of several lesions of skin and superficial soft tissues whose histologic character is a palisading granuloma with a small central focus of necrosis or necrobiosis. Unlike the other palisading necrobiotic lesions, DGA has a predilection for children in the first 5 to 6 years of life. A painless subcutaneous nodule(s) in the lower anterior tibial region or foot and the scalp, typically in the occiput, was the most common presenting feature in this study of 35 cases. Additional or recurrent lesions were reported in approximately 70% of cases with clinical follow-up. All lesions showed the presence of necrobiosis; however, one of the characteristic features was the multinodular character of the predominantly mononuclear cellular aggregates. The presence of vascular spaces at the periphery of the nodular profiles served as a clue to the diagnosis of DGA. The palisading arrangement of the mononuclear cells was evident only in those foci with central necrobiosis. A histiocytic disorder or fibrohistiocytic process was a common consideration in the differential diagnosis, especially in those cases with less apparent foci of necrosis. Palisading histiocytes with prominent eosinophilic cytoplasm and some nuclear atypism were problematic with regard to possible epithelioid sarcoma. Our study failed to identify any underlying or predisposing factors in the development of DGA. Despite the fact that DGA is a well-documented lesion in children, it occurs sufficiently infrequently that it is often not considered clinically when it presents as a subcutaneous mass or masses in a child. Its recognition by the pathologist is especially important as the occurrence of additional lesions in a high proportion of children can be anticipated without undue concern. Received June 16, 1997; accepted October 28, 1997.  相似文献   
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To investigate the role of the Maillard reaction in the pathogenesis of diabetic complications, we produced several clones of monoclonal antibodies against advanced glycation end products (AGEs) by immunizing mice with AGE-modified keyhole limpet hemocyanin, and found that one clone (AG-1) of the anti-AGE antibodies reacted specifically with imidazolones A and B, novel AGEs. Thus, the imidazolones, which are the reaction products of the guanidino group of arginine with 3-deoxyglucosone (3-DG), a reactive intermediate of the Maillard reaction, were found to be common epitopes of AGE-modified proteins produced in vitro. We determined the erythrocyte levels of imidazolone in diabetic patients using ELISA with the monoclonal anti-imidazolone antibody. The imidazolone levels in the erythrocytes of diabetic patients were found to be significantly increased as compared with those of healthy subjects. Then we studied the localization of imidazolone in the kidneys and aortas obtained from diabetic patients by immunohistochemistry using the antibody. Specific imidazolone immunoreactivity was detected in nodular lesions and expanded mesangial matrix of glomeruli, and renal arteries in an advanced stage of diabetic nephropathy, as well as in atherosclerotic lesions of aortas. This study first demonstrates the localization of imidazolone in the characteristic lesions of diabetic nephropathy and atherosclerosis. These results, taken together with a recent demonstration of increased serum 3-DG levels in diabetes, strongly suggest that imidazolone produced by 3-DG may contribute to the progression of long-term diabetic complications such as nephropathy and atherosclerosis.  相似文献   
999.
The protein Sex-lethal (SXL) controls pre-mRNA splicing of two genes involved in Drosophila sex determination: transformer (tra) and the Sxl gene itself. Previous in vitro results indicated that SXL antagonizes the general splicing factor U2AF65 to regulate splicing of tra. In this report, we have used transgenic flies expressing chimeric proteins between SXL and the effector domain of U2AF65 to study the mechanisms of splicing regulation by SXL in vivo. Conferring U2AF activity to SXL relieves its inhibitory activity on tra splicing but not on Sxl splicing. Therefore, antagonizing U2AF65 can explain tra splicing regulation both in vitro and in vivo, but this mechanism cannot explain splicing regulation of Sxl pre-mRNA. These results are a direct proof that Sxl, the master regulatory gene in sex determination, has multiple and separable activities in the regulation of pre-mRNA splicing.  相似文献   
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