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Pulmonary atresia with intact ventricular septum   总被引:1,自引:0,他引:1  
Neonates with pulmonary atresia with intact ventricular septum are ductus dependent from birth. The initial approach in these patients is to ensure continued adequate pulmonary blood flow in anticipation of imminent spontaneous closure of the ductus. Our experience and evolving approach in the management of 16 consecutive neonates with pulmonary atresia with intact ventricular septum from 1978 to 1984 is presented. On the basis of the revised classification by Bull and associates, we divided the patients into four different groups according to right ventricular morphology. Basically, three types of palliative surgical procedures were performed: systemic-pulmonary artery shunt; systemic-pulmonary artery shunt with pulmonary valvotomy; and pulmonary valvotomy alone. Systemic-pulmonary artery shunt is the most important part of neonatal palliation. Our present routine is to perform left subclavian-main pulmonary artery shunt with a polytetrafluoroethylene tube in all patients and, in addition, to perform an open transpulmonary valvotomy without cardiopulmonary bypass in patients with a patent infundibular portion of the right ventricle. Our technique and the advantages of this type of shunt procedure are discussed. Patients with right ventricular sinusoidal-coronary artery communications are a subgroup with an additional problem. In our series, patients with this anomaly are categorized into groups with major and minor connections and their surgical significance is discussed. Overall, there was one death among 16 patients after neonatal palliative procedures and one death among five patients after hemodynamic repair.  相似文献   
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Transforming growth factor-β1 (TGF-β1) is known to be a potent growth inhibitor for many cell types, including most epithelial cells. In skin keratinocytes, TGF-β1 has been shown to inhibit growth and to rapidly reduce c-mycexpression. However, the molecular mechanism of TGF-β1 action on cell growth of cervical carcinoma has not yet been elucidated. We thus assessed the effect of TGF-β1 on the growth of cervical carcinoma cell lines. Two cervical squamous carcinoma cell lines, CUMC-3 and CUMC-6, were incubated with varying concentrations of TGF-β1, and growth inhibition was evaluated with tetrazolium-based colorimetric assay. After culture in TGF-β1 for 24 h, inhibition of growth was detected in a dose-dependent manner at concentrations of 0.1–10 ng/ml in both cell lines. This effect of TGF-β1 on cultured carcinoma cells was associated with apoptotic process including oligonucleosomal ladder DNA and apoptotic body formations. Northern blot analysis revealed c-mycmRNA expression was suppressed by 10 ng/ml of TGF-β1 following 3 h of treatment in both cell lines. Western blot analysis showed that the level of p27Kip1protein was increased after TGF-β1 treatment in both cell lines. These results suggest that the mechanisms by which TGF-β1 inhibits the growth of cervical carcinoma are complex and may include effects on down-regulation of c-mycgene, and overexpression of p27Kip1protein.  相似文献   
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Accurate assessment and replacement of blood loss and fluid–electrolyte deficit during craniosynostosis repair is difficult owing to patient size and the diversity of surgical technique. Forty-three patients undergoing primary craniosynostosis repair over a 10-year period were studied retrospectively to determine blood loss and fluid deficit and to assess blood transfusion practices during both intraoperative and postoperative periods. Blood loss was calculated on the basis of estimated red cell mass (ERCM) and fluid-electrolyte imbalance was investigated with blood samplings. Blood transfusion was considered appropriate if the postoperative or posttransfusion ERCM was within 12% of the preoperative value. Estimated fluid requirement (EFR) was used in 4 ml kg–1 h–1 except for neonates. Intraoperatively, 80% of all patients were appropriately managed with respect to blood transfusion and EFR. Postoperatively only 20% of the patients receiving transfusions were transfused appropriately. In 23.3% of these patients (10/43) unexpected respiratory distress developed immediately after their recovery from the anesthesia. With the measurement of estimated blood volume and allowable blood loss, appropriate transfusion could be achieved for the successful treatment of the primary craniosynostosis. Received: 16 February 1998  相似文献   
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