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PubMed and Ovid Medline were searched to investigate the role of intramedullary nailing in the treatment of diaphyseal humeral non-union. Of 474 abstracts, 9 retrieved articles fulfilled our inclusion criteria and described management in 166 cases of humeral shaft non-union using several types of intramedullary nails. Union ranged from 40 to 100%; part of the variation could be explained by the quality index of the selected articles. Exchange nailing alone was not effective. Exposure of the fracture site and use of bone grafting were key to successful treatment. The total incidence of severe complications, including radial nerve damage, was very low. Thus, intramedullary nailing in the treatment of humeral shaft non-unions can lead to successful outcomes when associated with autologous bone grafting.  相似文献   
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BACKGROUND: Aim of our study was to evaluate the efficacy of multiagent intensive preoperative chemotherapy in patients with Ewing sarcoma family tumors (ESFT), in order to succeed a better percentage of necrosis before surgical resection. PROCEDURE: Eighteen patients with ESFT were treated with the same multiagent intensive preoperative protocol. 5/18 patients had bone Ewings sarcoma (EWS) and 13/18 had peripheral primitive neuroectodermal tumor (PNET). None had metastases at diagnosis. Chemotherapy consisted of 5 or 6 cycles with vincristine, cisplatin, cyclophosphamide, and Adriamycin, followed by 12 cycles of vincristine, cyclophosphamide, and actinomycin-D. Five patients with EWS underwent total resection after 5-6 cycles of preoperative chemotherapy and prosthetic replacement was performed in two of them. In 3/13 patients with PNET the tumor was resected at diagnosis and in 1/13 after 5 cycles of chemotherapy, while 9/13 patients received chemotherapy only and/or radiotherapy. RESULTS: In patients with EWS, the histologic specimens of the resected tumors showed that tissue necrosis was 100% in four patients and 95% in one patient. The good histologic response reflects the effectiveness of this regimen in all ESFT. No patient had topical recurrence or developed metastatic disease during follow-up period (2-13 years, mean time 7.4 years). All patients had the scheduled cycles without delays or dose reductions. There were no major side effects of chemotherapy. CONCLUSIONS: The intensive chemotherapy schedule, comprising of 5-6 cycles preoperatively, seems to maximize the percentage of tumor necrosis, thus improving outcome. Our study implies that this combined therapy may improve the prognosis of ESFT.  相似文献   
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Background and aim

Citrulline is a non-protein amino acid synthesized in the small intestine. In children with short-bowel syndrome, citrulline has served as a reliable marker of the residual bowel length and parenteral nutrition (PN) independence. In the present study we aim to assess the value of citrulline measurement in preterm neonates developing necrotizing enterocolitis (NEC).

Methods

Plasma citrulline levels were measured prospectively in 17 preterm neonates with NEC stage II during the entire course of the disease. Serial citrulline determinations in 24 healthy preterm neonates on 2, 7, 14, 21 and 28 days of life (DOL), served as reference values.

Results

In healthy preterm neonates plasma citrulline levels showed a progressive increase in relation to age. In neonates presenting with NEC, mean citrulline levels were significantly lower as compared to controls' citrulline levels of the most approximate day of life (DOL 7: 16.85 ± 4.2 vs 20.5 ± 4.5 μmol/L, p < 0.05; DOL 14: 18 ± 4.2 vs 23.5 ± 4.3 μmol/L, p < 0.01; DOL 21: 17 ± 2.5 vs 30 ± 5.7 μmol/L, p < 0.01). The optimal citrulline cut-off distinguishing NEC patient from controls was 17.75 μmol/L (sensitivity 76%, specificity 87%). Plasma citrulline at presentation correlated inversely with the duration of parenteral nutrition (r = − 0.49, p < 0.05). Consecutive citrulline determinations revealed that plasma citrulline increased during reintroduction and gradual increase of enteral nutrition.

Conclusions

Our findings provide preliminary evidence that citrulline levels that are reduced in preterm neonates with NEC in comparison to age-matched controls and serial citrulline determinations could help to monitor improvement of functional enterocyte mass during the course and resolution of NEC.  相似文献   
85.
We evaluated the pharmacokinetic profile of ciprofloxacin and its penetration into bronchial secretions of critically ill patients with chronic obstructive pulmonary disease (COPD). Twenty-five mechanically ventilated patients with severe COPD who were suffering from an acute, infectious exacerbation were included in this prospective, open-label study. All subjects received a 1-hour intravenous infusion of 400 mg ciprofloxacin every 8 h. Serial blood and bronchial secretion samples were obtained at steady state, and concentrations were determined using high-performance liquid chromatography. The pharmacodynamic parameters that are associated with the efficacy of fluoroquinolones against Gram-negative pathogens were also calculated. The mean peak (maximum) concentration (C(max)) and trough (minimum) concentration in plasma were 5.37 ± 1.57 and 1 ± 0.53 mg/liter, respectively. Mean values for volume of distribution, clearance, half-life, and area under the curve from 0 to 24 h (AUC(0-24)) were 169.87 ± 84.11 liters, 26.96 ± 8.86 liters/h, 5.35 ± 2.21 h, and 47.41 ± 17.02 mg · h/liter, respectively. In bronchial secretions, a mean C(max) of 3.08 ± 1.21 mg/liter was achieved in 3.12 ± 1.01 h, and the penetration ratio was 1.16 ± 0.59. The target of AUC(0-24)/MIC of ≥125 was attained in all patients, in the majority of them (76%), and in none at MICs of 0.125, 0.25, and 1 μg/ml, respectively. Slightly better results were obtained for the ratio C(max)/MIC of ≥10. In conclusion, ciprofloxacin demonstrates excellent penetration into bronchial secretions. There is wide interindividual variability in its pharmacokinetic parameters in critically ill COPD patients and inadequate pharmacodynamic exposure against bacteria with MICs of ≥0.5 μg/ml.  相似文献   
86.
Skin testing is the diagnostic cornerstone for allergies and is considered extremely safe. It is usually performed with the prick and the prick-to-prick method. The aim of this study is to report the first two pediatric cases of systemic allergic reactions during skin prick tests (SPT) with commercial food allergens. Both patients had a history of fish allergy. A 5-year-old girl, with a history of atopic dermatitis and asthma, reported an episode of urticaria and angioedema due to ingestion of fish, which had occurred 2 years before consultation. Ten minutes after having completed SPT to fish extracts, which had resulted positive, she suffered from generalized pruritus, nausea, stomach pain, and loss of consciousness. A 9-year-old boy, with a history of asthma and two episodes of acute urticaria and angioedema upon eating fish during infancy, reported a recent episode of oropharyngeal pruritus after tasting salmon. He was evaluated for fish allergy with SPT but developed conjunctivitis and acute urticaria during the first 10 min of the test. Anaphylaxis appears to be a rare side effect of skin testing in pediatric patients. Children with a history of asthma and atopic dermatitis are more likely to react.  相似文献   
87.
Several culprits may be identified at postmortem in sudden death (SD) victims, including coronary artery, myocardial, valve, conduction system, and congenital heart diseases. However, particularly in young people, the heart can be found grossly and histologically normal in a not-so-minor amount of cases (the so-called unexplained SD or “mors sine materia”) and inherited ion channel diseases are implicated (long and short QT syndromes, Brugada syndrome, and catecholaminergic polymorphic ventricular tachycardia). These channelopathies are due to defective genes encoding for proteins of sodium and potassium ion channels at the sarcolemma level or for receptors regulating intracellular calcium release at the sarcoplasmic reticulum level. Postmortem investigation may still represent the first opportunity to make the proper diagnosis also in the setting of a structurally normal heart and the employment of molecular biology techniques is of help to solve the puzzle of such “silent” autopsies. For these reasons, autopsy investigation of cardiac SD should always include sampling for genetic testing to search for the invisible inherited arrhythmogenic disorders, as recommended in the recent guidelines by the Association for European Cardiovascular Pathology.  相似文献   
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BACKGROUND/AIMS: Leptin has a particular profibrogenic role in the liver. We investigated whether IFN-alpha influences leptin production in patients with chronic hepatitis B (CHB) and C (CHC). Leptin was determined in serial samples from 63 CHB and 42 CHC IFN-alpha treated patients. Furthermore, we evaluated whether leptin alterations were associated with patients' characteristics. METHODS: Sera were investigated at serial time-points using an enzyme-linked-immunosorbent-assay. Controls consisted of 36 patients with autoimmune liver diseases and 44 healthy patients. RESULTS: Leptin levels before IFN-alpha administration were higher in CHB and CHC compared to healthy (P<0.004) and diseased controls (P=0.0001). In CHB patients, we observed a significant reduction of leptin during IFN-alpha treatment and lasting for up to 6 months after the end of treatment, followed by an increase reaching pretreatment levels at 1.5 years after stopping therapy. The pattern of leptin alterations was similar in CHC patients where leptin's decrease was more pronounced at 6 months after the end of treatment. Biochemical or virological response to treatment was not associated with leptin reduction in both groups. CONCLUSIONS: This study provides information on leptin kinetics during IFN-alpha treatment and follow-up in CHB and CHC patients and suggests IFN-alpha as a potential inhibitor of leptin production.  相似文献   
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