Susceptibilities to stress corrosion cracking （SCC） of X80 pipeline steel in high pH solutions with various concentrations of HC03 at a passive potential of-0.2 V vs. SCE were investigated by slow strain rate tensi...Susceptibilities to stress corrosion cracking （SCC） of X80 pipeline steel in high pH solutions with various concentrations of HC03 at a passive potential of-0.2 V vs. SCE were investigated by slow strain rate tensile （SSRT） test. The SCC mechanism and the effect of HC03 were discussed with the aid of electrochemical techniques. It is indicated that X80 steel shows enhunced susceptibility to SCC with the concentration of HCO3 increasing from 0.15 to 1.00 mol/L, and the susceptibility can be evaluated in terms of current density at -0.2 V vs. SCE. The SCC behavior is controlled by the dissolution-based mechanism in these circumstances. Increasing the concentration of HCO3 not only increases the risk of rupture of passive films but also promotes the anodic dissolution of crack tips. Besides, little susceptibility to SCC is found in dilute solution containing 0.05 mol/L HCO3 for X80 steel. This can be attributed to the inhibited repassivation of passive films, manifesting as a more intensive dissolution in the non-crack tip areas than at the crack tips.展开更多
目的:探讨行腹腔镜无功能肾切除患者的临床特征,分析合并上尿路手术史和无手术史患者之间影响手术复杂性的相关因素。方法:收集2017年1月至2023年11月于重庆医科大学附属第一医院泌尿外科接受腹腔镜无功能肾切除术患者的临床资料,回顾...目的:探讨行腹腔镜无功能肾切除患者的临床特征,分析合并上尿路手术史和无手术史患者之间影响手术复杂性的相关因素。方法:收集2017年1月至2023年11月于重庆医科大学附属第一医院泌尿外科接受腹腔镜无功能肾切除术患者的临床资料,回顾性分析上尿路手术史和无手术史患者的一般特征以及围手术期指标的变化。采用手术时间、估计失血量、中转开放手术率、术后并发症、术后住院时间等指标,评估腹腔镜单纯性肾切除手术的复杂性。结果:共纳入293例患者,其中94例合并上尿路手术史以及199例无手术史。与无手术史组相比,上尿路手术史组的估计失血量、中转开放手术率、手术时间均有所增加(P<0.001),而术后住院时间则无明显差异。在单因素方式分析中,上尿路手术史(P<0.001)是唯一影响估计失血量的因素。logistic回归模型显示上尿路手术史(OR=3.858,95%CI=1.796~8.287,P=0.001)和体质指数(body mass index,BMI)(OR=4.074,95%CI=1.887~8.796,P=0.001)是影响手术时间延长的独立预测因素。结论:腹腔镜单纯性肾切除术的复杂程度受多种因素影响。上尿路手术史是影响手术时间及估计失血量的独立因素。对于合并上尿路手术史患者,根据患者的临床特点合理的选择手术方式和治疗策略十分重要。展开更多
BACKGROUND Laparoscopic radical gastrectomy is widely used,and perioperative complications have become a highly concerned issue.AIM To develop a predictive model for complications in laparoscopic radical gastrectomy f...BACKGROUND Laparoscopic radical gastrectomy is widely used,and perioperative complications have become a highly concerned issue.AIM To develop a predictive model for complications in laparoscopic radical gastrectomy for gastric cancer to better predict the likelihood of complications in gastric cancer patients within 30 days after surgery,guide perioperative treatment strategies for gastric cancer patients,and prevent serious complications.METHODS In total,998 patients who underwent laparoscopic radical gastrectomy for gastric cancer at 16 Chinese medical centers were included in the training group for the complication model,and 398 patients were included in the validation group.The clinicopathological data and 30-d postoperative complications of gastric cancer patients were collected.Three machine learning methods,lasso regression,random forest,and artificial neural networks,were used to construct postoperative complication prediction models for laparoscopic distal gastrectomy and laparoscopic total gastrectomy,and their prediction efficacy and accuracy were evaluated.RESULTS The constructed complication model,particularly the random forest model,could better predict serious complications in gastric cancer patients undergoing laparoscopic radical gastrectomy.It exhibited stable performance in external validation and is worthy of further promotion in more centers.CONCLUSION Using the risk factors identified in multicenter datasets,highly sensitive risk prediction models for complications following laparoscopic radical gastrectomy were established.We hope to facilitate the diagnosis and treatment of preoperative and postoperative decision-making by using these models.展开更多
文摘Susceptibilities to stress corrosion cracking （SCC） of X80 pipeline steel in high pH solutions with various concentrations of HC03 at a passive potential of-0.2 V vs. SCE were investigated by slow strain rate tensile （SSRT） test. The SCC mechanism and the effect of HC03 were discussed with the aid of electrochemical techniques. It is indicated that X80 steel shows enhunced susceptibility to SCC with the concentration of HCO3 increasing from 0.15 to 1.00 mol/L, and the susceptibility can be evaluated in terms of current density at -0.2 V vs. SCE. The SCC behavior is controlled by the dissolution-based mechanism in these circumstances. Increasing the concentration of HCO3 not only increases the risk of rupture of passive films but also promotes the anodic dissolution of crack tips. Besides, little susceptibility to SCC is found in dilute solution containing 0.05 mol/L HCO3 for X80 steel. This can be attributed to the inhibited repassivation of passive films, manifesting as a more intensive dissolution in the non-crack tip areas than at the crack tips.
文摘目的:探讨行腹腔镜无功能肾切除患者的临床特征,分析合并上尿路手术史和无手术史患者之间影响手术复杂性的相关因素。方法:收集2017年1月至2023年11月于重庆医科大学附属第一医院泌尿外科接受腹腔镜无功能肾切除术患者的临床资料,回顾性分析上尿路手术史和无手术史患者的一般特征以及围手术期指标的变化。采用手术时间、估计失血量、中转开放手术率、术后并发症、术后住院时间等指标,评估腹腔镜单纯性肾切除手术的复杂性。结果:共纳入293例患者,其中94例合并上尿路手术史以及199例无手术史。与无手术史组相比,上尿路手术史组的估计失血量、中转开放手术率、手术时间均有所增加(P<0.001),而术后住院时间则无明显差异。在单因素方式分析中,上尿路手术史(P<0.001)是唯一影响估计失血量的因素。logistic回归模型显示上尿路手术史(OR=3.858,95%CI=1.796~8.287,P=0.001)和体质指数(body mass index,BMI)(OR=4.074,95%CI=1.887~8.796,P=0.001)是影响手术时间延长的独立预测因素。结论:腹腔镜单纯性肾切除术的复杂程度受多种因素影响。上尿路手术史是影响手术时间及估计失血量的独立因素。对于合并上尿路手术史患者,根据患者的临床特点合理的选择手术方式和治疗策略十分重要。
基金Natural Science Foundation of Fujian Province,No.2021J011360,and No.2020J011230Natural Science Foundation of Xiamen,China,No.3502Z20214ZD1018,and No.3502Z20227096+2 种基金Medical Innovation Project of Fujian Provincial Health Commission,No.2021CXB019Youth Scientific Research Project of Fujian Provincial Health Commission,No.2022QNB013Bethune Charitable Foundation,No.HZB-20190528-10.
文摘BACKGROUND Laparoscopic radical gastrectomy is widely used,and perioperative complications have become a highly concerned issue.AIM To develop a predictive model for complications in laparoscopic radical gastrectomy for gastric cancer to better predict the likelihood of complications in gastric cancer patients within 30 days after surgery,guide perioperative treatment strategies for gastric cancer patients,and prevent serious complications.METHODS In total,998 patients who underwent laparoscopic radical gastrectomy for gastric cancer at 16 Chinese medical centers were included in the training group for the complication model,and 398 patients were included in the validation group.The clinicopathological data and 30-d postoperative complications of gastric cancer patients were collected.Three machine learning methods,lasso regression,random forest,and artificial neural networks,were used to construct postoperative complication prediction models for laparoscopic distal gastrectomy and laparoscopic total gastrectomy,and their prediction efficacy and accuracy were evaluated.RESULTS The constructed complication model,particularly the random forest model,could better predict serious complications in gastric cancer patients undergoing laparoscopic radical gastrectomy.It exhibited stable performance in external validation and is worthy of further promotion in more centers.CONCLUSION Using the risk factors identified in multicenter datasets,highly sensitive risk prediction models for complications following laparoscopic radical gastrectomy were established.We hope to facilitate the diagnosis and treatment of preoperative and postoperative decision-making by using these models.
