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BACKGROUND: Diagnosis of atopic dermatitis (AD) depends on clinical features because no definitive diagnostic test exists. Criteria proposed by Hanifin and Rajka (Acta Derm Venereol (Stockh) 1980; Suppl 92: 44-47) were acceptable for hospital-based studies but were found not to be suitable for field studies. A UK working party formulated clinical diagnostic criteria that could be used in both hospital and epidemiological settings. Validation studies of the criteria showed widely variable results, probably due to different clinical settings and ethnicity. AIM AND OBJECTIVE: This study was undertaken to validate Hanifin and Rajka's criteria and to assess the comparative efficacy of their criteria and the UK working party's diagnostic criteria in the diagnosis of AD in a hospital setting in North India. SUBJECTS AND METHODS: This study serially included 101 patients with AD and 48 controls of paediatric age group. The study period was from July 2003 to December 2004. RESULTS: Hanifin and Rajka's criteria (sensitivity 96%, specificity 93.75%, positive predictive value 97% (PPV) and negative predictive value (NPV) 91.84%) had a statistical advantage over the UK working party's diagnostic criteria (sensitivity 86%, specificity 95.83%, PPV 97.75% and NPV 76.67%), with a P-value < 0.005.  相似文献   
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A lump on the midface of a child can pose as a diagnostic dilemma. There is a wide variety of possible differential diagnoses, ranging from simple benign conditions such as a sebaceous cyst, dermoid cyst, lipoma, neuroma and neurofibroma, to potentially devastating conditions such as odontogenic myxoma.A case of a child in which the formulation of a definite diagnosis was clinically and histologically challenging is presented.  相似文献   
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BACKGROUND: Acquired cerebriform intradermal naevus (CIN) is a rare form of pseudo cutis verticis gyrata. CASE REPORT: A case of acquired CIN of the scalp in a 46-year-old male patient is presented. The clinical and histopathological presentations of CIN are described and the therapeutic possibilities are discussed. CONCLUSIONS: In each individual case the physician must decide whether to do surgery or follow a wait-and-see policy. There is little risk of malignant change of CIN, and surgical excision of such lesions often involves evident mutilation.  相似文献   
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Objective: Right upper lobe collapse is a common radiographic finding in intubated children. We hypothesized that deep suctioning and uncontrolled negative pressures during endotracheal tube suctioning were significant contributory factors. Methods : The incidence of right upper lobe (RUL) collapse in intubated, ventilated children on a paediatric cardiac intensive care unit was determined over a 3-month period ( n = 102). Graduated suction catheters and suction vacuums of < 165 cm H2O were then introduced. Another prospective audit was carried out 3 months later ( n = 60). Results : We found that 24% developed RUL collapse and 4 developed an apical pneumothorax. Following the introduction of graduated catheters and controlled vacuums pressures, a significant reduction in the incidence of RUL collapse, to 7%, was observed ( p < 0.05). Conclusions : We conclude that high negative pressure and deep-suctioning causes RUL collapse in children. Any lobar collapse not only prolongs the child's stay in intensive care, but can be associated with further morbidity which may have a serious implication. By improving suctioning technique this morbidity can be significantly reduced.  相似文献   
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Recombination of deltaRec to psiJalpha will delete the TCR delta gene, which is thought to play an important role in the bifurcation of the TCR alphabeta versus TCR gammadelta differentiation lineages. We recently detected a DNA-binding protein in human thymocytes, the so- called PJA-BP, which recognizes the psiJalpha gene segment and might be one of the factors involved in the regulation of preferential deltaRec- psiJalpha rearrangements. We now investigate PJA-BP expression and its correlation with TCR delta gene deletion in thymocytes. Our electrophoretic mobility shift assay experiments showed that the PJA-BP is evolutionary conserved in human, murine and simian thymocytes. Using a large series of human hematopoietic malignancies (n = 30), we conclude that PJA-BP expression is thymocyte specific and seems to be restricted to thymocytes committed to the TCR alphabeta lineage. Analysis of seven well-defined human thymocyte subpopulations showed that preferential deltaRec-psiJalpha rearrangements as well as PJA-BP expression can be detected from the immature CD34-/CD1+/CD3- /CD4+/CD8alpha+beta- thymocyte differentiation stage onwards. These experiments indicate that expression of PJA-BP in human thymocytes starts simultaneously with preferential deltaRec-psiJalpha rearrangements, which supports our hypothesis that PJA-BP is one of the factors involved in the preferential recombination of deltaRec to psiJalpha.   相似文献   
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