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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   
54.
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   
55.
Weaning methods are an important ingredient in successful extubation. All too frequently, however, patient problems that thwart weaning are not identified or controlled. The pre-weaning assessment form in Table 2 should be used as an evaluation tool after the patient is intubated. Any "no" answers will indicate a common problem impeding weaning. Following problem identification, a plan of care can be developed using management strategies described in Table 3. Thus, a critical void in practice, impediments to weaning, is addressed. This article has addressed the need for the prevention or early identification of problems in mechanically ventilated patients. With this knowledge to guide our practice, we should be able to wean almost any patient.  相似文献   
56.
Septo-optic dysplasia: MR imaging   总被引:5,自引:0,他引:5  
Barkovich  AJ; Fram  EK; Norman  D 《Radiology》1989,171(1):189-192
Septo-optic dysplasia is the diagnosis when optic nerve hypoplasia is seen in conjunction with dysgenesis of the septum pellucidum. Nearly two-thirds of these patients have hypothalamic-pituitary dysfunction, and half have schizencephaly. The disorder is difficult to classify because of the diversity of clinical and pathologic manifestations. Magnetic resonance images of 11 patients with clinical and radiographic evidence of septo-optic dysplasia were reviewed retrospectively. The "syndrome" appears to include two subsets of patients whose abnormalities have different embryogenesis and neuropathologic findings. The existence of these two subsets helps to explain the diversity of the clinical and radiologic findings.  相似文献   
57.
Tissue sections embedded in paraffin and fixed in formalin from 32 patients with Hodgkin's disease, representing the major histological subtypes, were studied using two granulocyte specific monoclonal antibodies (Leu-M1 and 3C4) and an HLA-D region specific monoclonal antibody (TAL-IB5). Reed-Sternberg cells were stained with one or other of the antigranulocyte antibodies in the nodular sclerosing and lymphocyte depleted subtypes. Reed-Sternberg cells in all but three cases of mixed cellularity Hodgkin's disease were positive with both Leu-M1 and 3C4. One case stained with only Leu-M1, and two cases were consistently negative with both antibodies. HLA-DR was widely expressed in the Reed-Sternberg cells of all three subtypes. In the four cases of lymphocyte predominant Hodgkin's disease the multinucleated Reed-Sternberg cells did not stain with either antigranulocyte antibody but were strongly positive with anti-HLA-DR. Twenty five cases of non-Hodgkin's lymphoma, in which there were multinucleated giant cells resembling Reed-Sternberg cells, were studied in a similar way. These cases included pleomorphic T cell and B cell lymphomas, histiocytic lymphomas, and malignant histiocytosis of the intestine. In none of these did the multinucleated cells stain with either antigranulocyte antibody, but in most cases the multinucleated cells stained with anti-HLA-DR. In two cases of the tumour stage of mycosis fungoides dot like intracytoplasmic staining was shown in the tumour cells with both antigranulocyte markers. The monoclonal antigranulocyte antibodies Leu-M1 and 3C4 are of considerable value in both the diagnosis and the differential diagnosis of Hodgkin's disease and are particularly valuable in that they can be applied to tissue fixed in formalin and embedded in paraffin. Antibody to HLA-DR, while useful, is of less value.  相似文献   
58.
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   
59.
Summary Ninety-one percent (n=182) of the female members of South Australian representative squads in 14 sports volunteered to act as subjects. Twenty-seven percent of them had represented Australia. The underwater weighing method together with the measurement of residual volume (RV) by helium dilution were used to determine body density (BD); the percent body fat (% BF) was then computed according to Siri.A stepwise multiple regression analysis yielded a correlation coefficient (R) of 0.863 between the criterion (BD) and the best weighted sum of predictors (anthropometric variables): BD (g·cm–3)=1.14075–0.04959 (log10 triceps, subscapular, supraspinale and calf skinfolds in mm)+0.00044 (age in decimal years)–0.000612 (waist girth in cm)+0.000284 (height in cm)–0.000505 (gluteal girth in cm)+0.000331 (breast girth in cm).Only those predictors which resulted in a statistically significant increase inR (p0.05) were included. The standard error of estimate of 0.00597 g · cm–3 was equivalent to 2.7% BF at the mean. This equation was shown to be largely population specific. There was a range of 7.6–35.8% of BF and the overall mean of 18.5% was significantly lower (p<0.001) than that of 23.4% obtained on a moderately active reference sample of similar age (n=135). If group sizes of only one or two are regarded as too small for meaningful comparison, then the lowest mean of 13.5% was achieved by the long-distance runners (n=14). The highest averages were registered by the heavyweight rowers (24.2%;n=7) and soccer players (22.0%;n=11). The overall average for games players (n=107) was 19.4%.This study was supported by a grant from the National Health and Medical Research Council of Australia  相似文献   
60.
Influenza nucleoprotein (NP)-specific T-cell receptor transgenic mice (F5) were crossed with transgenic mice expressing the cognate antigenic protein under the control of the H- 2Kb promoter. Double-transgenic mice show negative selection of thymocytes at the CD4+8+TCR10 to CD4+8+TCRhi transition stage. A few CD8 T cells, however, escape clonal deletion, and in the peripheral lymphoid organs of these mice, they exhibit low levels of the transgenic receptor and upregulated levels of the CD44 memory marker. Such cells do not proliferate upon exposure to antigen stimulation in vivo or ex vivo, however, they can develop low but detectable levels of antigen-specific cytotoxic function after stimulation in vitro in the presence of IL-2.  相似文献   
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