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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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The zinc level in serum and whole blood was determined in a series of 121 patients, 20 suffering from overt hyperthyroidism, 34 with manifest hypothyroidism and a control group of 67 euthyroid subjects. The zinc content per deciliter of erythrocytes was calculated from the haematocrit. The hyperthyroid group revealed a highly significantly elevated serum zinc level (p less than 0.01), but a most significantly reduced zinc content in whole blood (p less than 0.001) in comparison with the euthyroid group. On the other hand, the reverse changes were observed in the hypothyroid group, i.e. a most significantly reduced serum zinc content (p less than 0.001) and a highly significantly increased zinc content in whole blood (p less than 0.01). These results suggest that the determination of zinc levels both in serum and in whole blood may be a useful additional parameter of peripheral thyroid hormone effect.  相似文献   
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In this paper we propose a method for construction of feed-forward neural classifiers based on regularization and adaptive architectures. Using a penalized maximum likelihood scheme, we derive a modified form of the entropic error measure and an algebraic estimate of the test error. In conjunction with optimal brain damage pruning, a test error estimate is used to select the network architecture. The scheme is evaluated on four classification problems.  相似文献   
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Nine children, aged 5 to 11 years, with subacute or chronic meningitis were studied. Symptoms started during the summer season in all patients and in eight of the patients the disease began with a localized erythematous lesion (ECM), mostly in the face. In one patient only there was a history of an insect bite at the site of the erythema. The neurological abnormalities included aseptic meningitis, peripheral facial nerve palsy (5/9) and oculomotor nerve palsy (1/9). Most children complained of headache, fatigue, loss of appetite and had a low grade fever. High antibody titers to Borrelia spirochetes in serum and/or cerebrospinal fluid (CSF) were demonstrated by ELISA in eight of the nine patients and by indirect immunofluorescence assay (IFA) in three patients. All patients had a dramatic improvement in their general condition and became afebrile within three days of institution of i.v. penicillin G treatment (i.v. cefuroxime in one patient).  相似文献   
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Previously infertile couples and the newborn intensive care unit   总被引:1,自引:0,他引:1  
Having a newborn child admitted to a newborn intensive care unit can be a traumatic experience for parents; however, parents who previously have been infertile face unique problems in coping with this situation. The authors discuss the difficulties parents must overcome in resolving their crises and in developing a good relationship with their child, or, in some cases, coming to terms with the child's death or ongoing disability. In addition, the authors offer suggestions for effective social work intervention.  相似文献   
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Corneal abrasion is the most common ocular injury occurring in the perioperative period. Corneal abrasion may occur during general anesthesia, monitored anesthesia care, regional anesthesia, or in the immediate recovery period. This injury is not usually apparent until the patient is in the PACU, and the perianesthesia nurse may be the first clinician to detect this complication. Preventive measures and vigilant care can help reduce the incidence of corneal abrasion in susceptible patients. Early detection and prompt intervention may help reduce the incidence of ocular morbidity. The purpose of this article is to explore the incidence, mechanism of injury, prevention, recognition, and treatment of perioperative corneal abrasion.  相似文献   
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