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81.
To estimate the incidence and causes of secondary thrombocytosis in children, a 12 month study of all patients attending a children's hospital and discovered to have a platelet count over two times the upper normal limit (> 800 x 10(9)/l) was undertaken. Data so obtained were analysed both separately and together with those from two previous studies to gain as broad a perspective as possible. Of 7916 children who had platelet counts during the study period, 36 (0.5%) produced a value > 800 x 10(9)/l; there were 19 boys and 17 girls. There was a preponderance of young infants (median age 13 months). Twenty seven of the 36 had some sort of associated infection, bacterial in 18 and viral in nine. The other nine were either recovering from anti-neoplastic chemotherapy (n = 6), were post-operative (n = 2), or simply iron deficient (n = 1). Combining these patients with those described in previous studies allowed a review of 139 unselected children with very high platelet counts. Fifty three (38%) had infections, 29 (20%) had traumatic or surgical tissue damage, 16 (11%) had malignant disease undergoing chemotherapy or surgery, and 13 (9%) had connective tissue or autoimmune disorders. Secondary thrombocytosis is not rare and is most frequently seen in very young infants after infection. It can arise in a wide variety of other circumstances including rebound from myelosuppression, iron lack, or as part of an acute phase response. It is clinically unimportant in terms of morbidity and requires no treatment other than that for the primary condition.  相似文献   
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It is postulated that a vigorous host inflammatory response in the cystic fibrosis lung contributes to lung injury. Tumour necrosis factor-alpha (TNF-alpha) may play a part in that process and in the generation of leukotrienes. Therefore, the relationships between sputum TNF-alpha, leukotriene concentration, and lung function abnormalities in 16 children with cystic fibrosis were investigated. Each subject provided sputum samples and performed spirometry. TNF-alpha was measured by enzyme linked immunosorbent assay; individual leukotrienes were separated using high performance liquid chromatography and quantified by radioimmunoassay. The geometric mean concentration of TNF-alpha was 129.7 pg/ml and 95% confidence interval 48.2 to 348.3. Mean (SEM) leukotriene B4 (LTB4) was 97.8 (22.9) pmol/g and total cysteinyl leukotrienes were 60.9 (14.8) pmol/g. Mean (SD) forced expiratory volume in one second (FEV1) of the group was 53 (15)% of predicted and forced vital capacity (FVC) was 65 (14)% of predicted. There was a significant positive correlation between TNF-alpha and both LTB4 and the total cysteinyl leukotriene sputum content. An inverse relationship existed between TNF-alpha and FEV1 and FVC. Moreover, a negative correlation was observed between sputum LTB4 and FEV1 and FVC. These results suggest that TNF-alpha and the leukotrienes may participate in the airways inflammation and airflow obstruction observed in cystic fibrosis subjects and support the hypothesis that TNF-alpha upregulates the 5-lipoxygenase pathway in vivo.  相似文献   
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Renal cell carcinoma is a rare pediatric malignancy that appears to have a similar clinical outcome in children and adults. We review the experience of Childrens Hospital Los Angeles and compare it with the published pediatric series, reporting on seven cases from 1954 to the present. As in earlier pediatric series, we find that Stage I/II patients do well (five of five complete responses with prolonged disease-free survival) with surgical resection. As in other pediatric series, our only Stage III patient died of disease. We also report on a recent case of renal cell carcinoma, metastatic to lymph nodes and lung parenchyma at diagnosis (Stage IV). This patient was treated with high dose continuous infusion recombinant interleukin-2 and had a partial response. The patient attained a complete response following a second laparotomy and two subsequent cycles of recombinant interleukin-2. He is presently well, without evidence of disease, 3 1/2 years after diagnosis. The significance of this form of therapy to advanced renal cell carcinoma in childhood is discussed. © 1994 Wiley-Liss, Inc.  相似文献   
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Two patients had colonic perforation as a result of percutaneous nephrostomy placement followed by track dilatation and renal calculus removal. We present the technical aspects of nephrostomy placement and stone removal, as well as the clinical diagnosis and management of these cases. Both patients recovered well with conservative therapy and required no surgical intervention. This report reviews the anatomic considerations for percutaneous nephrostomy in patients undergoing renal stone removal.  相似文献   
90.
Surgical repair of double aortic arch: 16-year experience   总被引:1,自引:0,他引:1  
Double aortic arch (DAA) is a complete form of vascular ring causing tracheoesophageal compression. We analyzed long-term results of a series of DAAs, over a period of 16 years. Between 1987 and 2003, 29 children underwent surgery for airway and/or esophageal compression secondary to a DAA. Dominant symptoms were stridor, dysphagia, choking episodes, and life-threatening apneic spells (n = 7). Diagnosis was established by barium studies, bronchoscopy, echocardiogram, angiogram, computed tomography (CT), and magnetic resonance imaging (MRI). Seven patients had concurrent cardiac anomalies. Two children had an associated tracheoesophageal fistula. Surgery was accomplished by left thoracotomy (n = 25), right thoracotomy (n = 2) or median sternotomy (n = 2). The operative mortality was zero. There was one late death due to respiratory failure. Four (13.8%) patients had a surgical complication (chylothorax, 3 cases; acute renal failure, 1 case). Follow-up (mean 7.1 years; range 6 months to 16 years) was complete in all patients, and showed complete improvement in 22 patients and partial improvement in 6 patients. Early surgical repair of DAA is associated with low mortality, and results in marked symptomatic relief in most patients. Patients with tracheomalacia or associated asthma, constitute a high-risk group and may manifest persistent symptoms and require adjunctive procedures.  相似文献   
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