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Background Atopic eczema is an increasing clinical problem in Africa. Objective To determine allergic characteristics and to identify possible risk factors for eczema among schoolchildren in an urbanized area in Ghana. Patients and methods Schoolchildren aged 3–16 years with eczema were recruited. For each patient, one to three age‐ and sex‐matched controls were selected. All children completed a questionnaire and were skin prick tested with a panel of allergens. Blood was drawn to determine the total and allergen‐specific IgE. Conditional logistic regression models with the matching factors included in the model were used to calculate the odds ratios and to adjust for possible confounders. Results A total of 52 children with eczema (27 boys and 25 girls) and 99 controls were included. Levels of total IgE were found to be 9.1 (1.1; 78.4) times more often elevated in children with eczema. This association was mainly driven by elevated IgE levels against cockroach antigen. Children with eczema were found to have 2.0 (0.87; 4.7) times more often positive skin prick tests (SPT), but this association diminished to 1.2 (0.40; 3.6) after adjustment for total IgE levels. Frequent washing with soap was identified as a risk factor for the development of eczema among these children. Conclusion Schoolchildren with eczema in Ghana were characterized by elevated IgE levels especially against cockroach antigen. The association between eczema and positive SPT was much weaker suggesting immune hyporesponsiveness of the skin. After adjustment for IgE level, SPT were less suitable to distinguish children with and without eczema.  相似文献   
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OBJECTIVES: To evaluate the ability of clinicians involved in the provision of paediatric intensive care to estimate cardiac index in ventilated children, based on physical examination and clinical and bedside laboratory data. METHODS: Clinicians were exposed to all available haemodynamic and laboratory data for each patient, allowed to make a physical examination, and asked to first categorize cardiac index as high, high to normal, low to normal, or low, and then to quantify this further with a numerical estimate. Cardiac index was measured simultaneously by femoral artery thermodilution (coefficient of variation 5.37%). One hundred and twelve estimates were made by 27 clinicians on 36 patients (median age 34.5 months). RESULTS: Measured cardiac index ranged from 1.39 to 6.84 1/min/m2. Overall, there was poor correlation categorically (kappa statistic 0.09, weighted kappa 0.169) and numerically (r = 0.24, 95% confidence interval 0.06 to 0.41), although some variation was seen among the various levels of seniority. CONCLUSION: Assuming that objective measurement, and hence manipulation, of haemodynamic variables may improve outcome, these findings support the need for a safe, accurate, and repeatable technique for measurement of cardiac index in children who are critically ill.  相似文献   
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Haagen  IA; Geerars  AJ; de Lau  WB; Bast  BJ; de Gast  BC 《Blood》1995,85(11):3208-3212
To evaluate the potency by which human T cells are targeted and activated by bispecific monoclonal antibodies (BsAbs) to lyse tumor cells, a clonogenic assay was developed. The efficacy of a CD3 x CD19 BsAb binding to both the CD3 T-cell antigen and the CD19 B-cell antigen was already proven in 51Cr-release assays and in 3-day activation cultures. To achieve more quantitative results, a 14-day clonogenic assay, based on limiting-dilution, was performed for the determination of the initial and residual number of clonogenic units obtained with a CD19+ pre-pre-B acute lymphoblastic leukemia (ALL-B) cell line. Elimination of up to 5 logs of ALL-B cells by freshly isolated peripheral blood mononuclear cells (PBMCs) cultured with BsAb plus interleukin-2 (IL-2) could be detected. The presence of human IgG did not abolish the effect. Repeated addition of each of the two agents was necessary, because a single treatment produced only a 1- to 2-log kill. CD3 monoclonal antibody and IL-2 stimulation ("lymphokine-activated killer cell" conditions) resulted in only a 2-log kill. The number of T cells proved critical in lysis of ALL-B cells, with a 5-log kill using a T-cell:B-cell ratio of 3:1 but with only a 1-log kill using a ratio of 1:1. PBMCs isolated from patients with non-Hodgkin's lymphoma, both in relapse or remission, proved to be as competent as those from healthy donors in removing ALL-B cells. This clonogenic assay shows the importance of repeated administration of CD3 x CD19 BsAb and IL-2 and offers the possibility to compare it with other therapies in B-cell malignancy.  相似文献   
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A wide range of invasive and non-invasive techniques for monitoring the haemodynamic condition of critically ill patients is now available. A general reluctance on the part of paediatric intensive care specialists to use pulmonary artery thermodilution catheters and the need for constant realignment of hand-held Doppler probes has necessitated the search for a technique which is relatively non-invasive and provides continuous information on the haemodynamic condition of critically ill paediatric patients. We sought to establish if transoesophageal Doppler fulfilled these criteria. Eleven children who had recently undergone cardiac surgery were studied. Median age was 39 months and weight 14.9 kg. Five simultaneous pairs of measurements of cardiac index (CI: thermodilution) and minute distance (MD: transoesophageal Doppler) were made, as a baseline, when each child was haemo-dynamically stable. Following a fluid challenge, five repeat pairs of measurements were made. The mean percentage changes for CI and MD were 16.4% (range 5.3-44%) and 16.6% (3.4-47.7%), respectively. The average coefficients of variation for measurements of CI and MD were 3.5% and 2.9%, respectively. The mean difference in percentage change between CI and MD was -0.5% (95% confidence interval for the bias –4% to 3%; limits of agreement –10.7 to +9.7%). Our study indicates that transoesophageal Doppler is reproducible, easy to use and provides clinically acceptable information when following changes in CI in haemodynamically stable paediatric patients. ? Cardiac index, minute distance, pulmonary artery catheter, thermodilution, transoesophageal Doppler  相似文献   
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