AIM: To evaluate the clinical outcome of Ivor Lewis subtotal esophagectomy with two-field lymphadenectomy for patients with squamous cell carcinoma of the lower thoracic esophagus. METHODS: From January 1998 to Dece...AIM: To evaluate the clinical outcome of Ivor Lewis subtotal esophagectomy with two-field lymphadenectomy for patients with squamous cell carcinoma of the lower thoracic esophagus. METHODS: From January 1998 to December 2001, 73 patients with lower thoracic esophageal carcinoma underwent Ivor-Lewis subtotal esophagectomy with two-field lymphadenectomy. Clinicopathological information, postoperative complications, mortality and long term survival of all these patients were analyzed retrospectively. RESULTS: The operative morbidity and mortality was 15.1% and the mortality was 2.7%. Lymph node metastases were found in 52 patients (71.2%). Nodal metastases to the upper, middle, lower mediastini and upper abdomen were found in 13 (17.8%), 15 (20.5%), 30 (41.1%), and 25 (34.2%) patients, respectively. Postoperative staging was as follows: stage Ⅰ in 5 patients, stage Ⅱ in 34 patients, stage Ⅲ in 32 patients, and stage Ⅳ in 2 patients, respectively. The overall 5-year survival rate was 23.3%. For NO and N1 patients, the 5-year survival rate was 38.1% and 17.3%, respectively (X^2 = 22.65, P 〈 0.01). The 5-year survival rate for patients in stages Ⅱ a, Ⅱ b and Ⅲ was 31.2%, 27.8% and 12.5%, repsectively (X^2 = 29.18, P 〈 0.01). CONCLUSION: Ivor Lewis subtotal esophagectomy with two-field (total mediastinum) lymphadenectomy is a safe and appropriate operation for squamous cell carcinoma of the lower thoracic esophagus.展开更多
文摘AIM: To evaluate the clinical outcome of Ivor Lewis subtotal esophagectomy with two-field lymphadenectomy for patients with squamous cell carcinoma of the lower thoracic esophagus. METHODS: From January 1998 to December 2001, 73 patients with lower thoracic esophageal carcinoma underwent Ivor-Lewis subtotal esophagectomy with two-field lymphadenectomy. Clinicopathological information, postoperative complications, mortality and long term survival of all these patients were analyzed retrospectively. RESULTS: The operative morbidity and mortality was 15.1% and the mortality was 2.7%. Lymph node metastases were found in 52 patients (71.2%). Nodal metastases to the upper, middle, lower mediastini and upper abdomen were found in 13 (17.8%), 15 (20.5%), 30 (41.1%), and 25 (34.2%) patients, respectively. Postoperative staging was as follows: stage Ⅰ in 5 patients, stage Ⅱ in 34 patients, stage Ⅲ in 32 patients, and stage Ⅳ in 2 patients, respectively. The overall 5-year survival rate was 23.3%. For NO and N1 patients, the 5-year survival rate was 38.1% and 17.3%, respectively (X^2 = 22.65, P 〈 0.01). The 5-year survival rate for patients in stages Ⅱ a, Ⅱ b and Ⅲ was 31.2%, 27.8% and 12.5%, repsectively (X^2 = 29.18, P 〈 0.01). CONCLUSION: Ivor Lewis subtotal esophagectomy with two-field (total mediastinum) lymphadenectomy is a safe and appropriate operation for squamous cell carcinoma of the lower thoracic esophagus.
文摘直流分压器是直流输电系统中不可缺少的主设备。目前直流阻容式分压器因结构和工作原理的原因,导致内部出现较大的温度梯度,影响了分压器的误差性能,同时增加了空心绝缘子发生污秽闪络的概率。针对±1 100 kV直流分压器的散热问题,文中进行了内部温度场的结构优化设计,同时在顶部增加散热结构,降低其温度梯度。最后利用Ansys Fluent软件对该结构设计进行温度场和热流场的仿真分析,结果表明:在27℃的环境温度下,与传统结构的直流分压器相比,在额定一次电流为2 m A,热流量为2.2 k W的情况下,其内部温度有明显的降低,最大温差可达到20 K。同时增加的散热翅片显著提高了分压器内部气体的循环流动,提高了散热的效率,优化后的结构满足散热的需求。