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1.
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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A new technique for measuring intraosseous pressures involves inserting a miniature transducer directly into the intraosseous space. A high-performance, high-fidelity pressure transducer is easy to assemble and insert. The transducer permits dynamic studies of intraosseous pressure during gait, and constitutes a promising tool for detecting changes in intraosseous pressure in osteoarthritis and osteonecrosis.  相似文献   
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Alcohol misuse remains the single most important contributing factor to road accident deaths and injuries in Australia. The results of compulsory blood alcohol tests on road casualties have shown that probationary licensed drivers have a threefold increased risk of road accident injury compared to fully licensed drivers and are additionally over-represented in alcohol-related crashes. These findings led the Victorian Road Trauma Committee to campaign for a zero blood alcohol limit for learner and probationary drivers and motorcyclists. In May 1984, zero blood alcohol legislation was enacted in Victoria. The present legislation applies to learner and first year probationary licence holders. For the first time we have evidence of a moderate reduction in alcohol-related road trauma in Victoria. Between 1977 and 1983 there has been a significant reduction in the proportion of driver casualties admitted to hospital with illegal blood alcohol concentrations and in the number of driver fatalities with blood alcohol concentrations in excess of 0.15 g%. An evaluation of the following recommended drink driver countermeasures is presented: improved driver education, increased penalties, re-education--rehabilitation programmes for convicted drink drivers, interlock devices and an increase in the legal drinking age.  相似文献   
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Human Fallopian tubal epithelial cells in culture lose morphological features associated with the epithelium in situ and the extent to which they retain their in-vivo phenotype or function is unknown. In order to address this question, immunocytochemical markers were identified which distinguish secretory (HMFG2+, LhS28-) from ciliated (HMFG2-, LhS28+) epithelial cells in tissue sections of Fallopian tube. These markers were used to analyse the phenotype of tubal cells in vitro. Primary cultures of human tubal epithelial cells were seeded onto glass and grown to confluence before addition of oestradiol-17beta. In the absence of hormone, tubal epithelial cells expressed cytokeratins and nuclear receptors for oestrogen and progesterone and adopted a homogeneous (HMFG2+, LhS28-) secretory cell phenotype. Following the addition of oestradiol-17beta, a proportion of cells became positive for LhS28. The induction of a ciliated epithelial cell phenotype was confirmed by scanning electron microscopy, where on permeable collagen membranes, approximately one-third of tubal epithelial cells became ciliated in the presence of oestradiol-17beta. We suggest that in vitro, tubal epithelial cells adopt an immature secretory-like phenotype and that oestrogen can induce differentiation to a ciliated epithelial cell phenotype.   相似文献   
8.
The T-cell receptor β locus (TCRB) on chromosome 7q35 was studied as a candidate region for genetic susceptibility to type 1 insulin-dependent diabetes (IDDM). A highly polymorphic microsatellite marker mapping to the TCRBV6.7 gene and a TCRB C-region RFLP were used to genotype the members of a total of 21 multiplex IDDM families from two different geographical areas. There was no evidence to support linkage to either of these markers with IDDM, and conventional two-point analysis excluded linkage to the telomeric end of the TCRB complex, in the region of the highly informative TCRBV6.7 marker. There was significant linkage of IDDM to the class II HLA-D locus with significant lod scores >3.0 obtained for the HLA-DRB1 and HLA-DQB1 genes. Affected sib-pair (ASP) and transmission disequilibrium (TDT) association tests confirmed these findings.  相似文献   
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Diurnal and weekly cyclical changes in lung airways resistance   总被引:1,自引:0,他引:1  
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