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"Five steps four quadrants" modularized en bloc dissection technique for accessing hepatic hilum lymph nodes in laparoscopic pancreaticoduodenectomy
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作者 Xiao-Si Hu Yong Wang +5 位作者 Hong-Tao Pan Chao Zhu Shi-Lei Chen Hui-Chun Liu Qing Pang Hao Jin 《World Journal of Gastrointestinal Surgery》 SCIE 2024年第2期503-510,共8页
BACKGROUND Although en bloc dissection of hepatic hilum lymph nodes has many advantages in radical tumor treatment,the feasibility and safety of this approach for laparo-scopic pancreaticoduodenectomy(LPD)require furt... BACKGROUND Although en bloc dissection of hepatic hilum lymph nodes has many advantages in radical tumor treatment,the feasibility and safety of this approach for laparo-scopic pancreaticoduodenectomy(LPD)require further clinical evaluation and investigation.AIM To explore the application value of the"five steps four quadrants"modularized en bloc dissection technique for accessing hepatic hilum lymph nodes in LPD patients.METHODS A total of 52 patients who underwent LPD via the"five steps four quadrants"modularized en bloc dissection technique for hepatic hilum lymph nodes from April 2021 to July 2023 in our department were analyzed retrospectively.The patients'body mass index(BMI),preoperative laboratory indices,intraoperative variables and postoperative complications were recorded.The relationships between preoperative data and intraoperative lymph node dissection time and blood loss were also analyzed.RESULTS Among the 52 patients,36 were males and 16 were females,and the average age was 62.2±11.0 years.There were 26 patients with pancreatic head cancer,16 patients with periampullary cancer,and 10 patients with distal bile duct cancer.The BMI was 22.3±3.3 kg/m²,and the median total bilirubin(TBIL)concentration was 57.7(16.0-155.7)µmol/L.All patients successfully underwent the"five steps four quadrants"modularized en bloc dissection technique without lymph node clearance-related complications such as postoperative bleeding or lymphatic leakage.Correlation analysis revealed significant associations between preoperative BMI(r=0.3581,P=0.0091),TBIL level(r=0.2988,P=0.0341),prothrombin time(r=0.3018,P=0.0297)and lymph node dissection time.Moreover,dissection time was significantly correlated with intraoperative blood loss(r=0.7744,P<0.0001).Further stratified analysis demonstrated that patients with a preoperative BMI≥21.9 kg/m²and a TIBL concentration≥57.7μmol/L had significantly longer lymph node dissection times(both P<0.05).CONCLUSION The"five steps four quadrants"modularized en bloc dissection technique for accessing the hepatic hilum lymph node is safe and feasible for LPD.This technique is expected to improve the efficiency of hepatic hilum lymph node dissection and shorten the learning curve;thus,it is worthy of further clinical promotion and application. 展开更多
关键词 Five steps four quadrants Hepatic hilum lymph node Modularized en bloc clearance Laparoscopic pancreaticoduodenectomy
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Expanding endoscopic boundaries:Endoscopic resection of large appendiceal orifice polyps with endoscopic mucosal resection and endoscopic submucosal dissection
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作者 Ankur P Patel Mai A Khalaf +2 位作者 Margarita Riojas-Barrett Tara Keihanian Mohamed O Othman 《World Journal of Gastrointestinal Endoscopy》 2023年第5期386-396,共11页
BACKGROUND Large appendiceal orifice polyps are traditionally treated surgically.Recently,endoscopic mucosal resection(EMR)and endoscopic submucosal dissection(ESD)have been utilized as alternative resection technique... BACKGROUND Large appendiceal orifice polyps are traditionally treated surgically.Recently,endoscopic mucosal resection(EMR)and endoscopic submucosal dissection(ESD)have been utilized as alternative resection techniques.AIM To evaluate the efficacy and safety of endoscopic resection techniques for the management of large appendiceal orifice polyps.METHODS This was a retrospective observational study conducted to assess the feasibility and safety of EMR and ESD for large appendiceal orifice polyps.This project was approved by the Baylor College of Medicine Institutional Review Board.Patients who underwent endoscopic resection of appendiceal orifice polyps≥1 cm from 2015 to 2022 at a tertiary referral endoscopy center in the United States were enrolled.The main outcomes of this study included en bloc resection,R0 resection,post resection adverse events,and polyp recurrence.RESULTS A total of 19 patients were identified.Most patients were female(53%)and Caucasian(95%).The mean age was 63.3±10.8 years,and the average body mass index was 28.8±6.4.The mean polyp size was 25.5±14.2 mm.74%of polyps were localized to the appendix(at or inside the appendiceal orifice)and the remaining extended into the cecum.68%of polyps occupied≥50%of the appendiceal orifice circumference.The mean procedure duration was 61.6±37.9 minutes.Polyps were resected via endoscopic mucosal resection,endoscopic submucosal dissection,and hybrid procedures in 5,6,and 8 patients,respectively.Final pathology was remarkable for tubular adenoma(n=10)[one with high grade dysplasia],sessile serrated adenoma(n=7),and tubulovillous adenoma(n=2)[two with high grade dysplasia].En bloc resection was achieved in 84%with an 88%R0 resection rate.Despite the large polyp sizes and challenging procedures,89%(n=17)of patients were discharged on the same day as their procedure.Two patients were admitted for post-procedure observation for conservative pain management.Eight patients underwent repeat colonoscopy without evidence of residual or recurrent adenomatous polyps.CONCLUSION Our study highlights how endoscopic mucosal resection,endoscopic submucosal dissection,and hybrid procedures are all appropriate techniques with minimal adverse effects,further validating the utility of endoscopic procedures in the management of large appendiceal polyps. 展开更多
关键词 Appendiceal orifice polyps endoscopic mucosal resection endoscopic submucosal dissection Polyp resection Adenomatous polyps en bloc resection
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前缀en-与后缀-en
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作者 尹继友 彭爱武 《英语自学》 2007年第9期45-45,共1页
前缀en-和后缀-en尽管词缀形式相同,但两者的构词功能迥然不同,前者仅用作动词词缀,而后者可作动词、形容词及名词词缀。因此不能将两者混为一谈。现分述如下:
关键词 en SPOKen enlarge deepen encourage endanger silenc
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基于高频数据和EN-LSTM的黄金期货短期波动率预测
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作者 邱冬阳 丁玲 何一夫 《运筹与管理》 CSCD 北大核心 2024年第3期184-190,共7页
以上海黄金期货2019—2020年期间的1分钟高频交易数据为样本,选取具有变量选择和长短期记忆特性的EN-LSTM,运用滚动时间窗口的样本外预测,对比不同数据频率的短期波动率预测模型对波动率的刻画和预测能力。实证研究表明:EN-LSTM能拟合... 以上海黄金期货2019—2020年期间的1分钟高频交易数据为样本,选取具有变量选择和长短期记忆特性的EN-LSTM,运用滚动时间窗口的样本外预测,对比不同数据频率的短期波动率预测模型对波动率的刻画和预测能力。实证研究表明:EN-LSTM能拟合上海黄金期货高频交易波动率特征;数据频率会对上海黄金期货短期波动率的预测带来显著影响,1分钟的数据频率预测精度明显高于更为低频的数据。研究结论有助于黄金期货市场参与各方分散和化解金融风险。 展开更多
关键词 高频数据 机器学习 en-LSTM 黄金期货
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基于EN 15273的车辆动态限界计算方法研究
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作者 易晓丹 谢红兵 +3 位作者 王永 张宝珍 夏梦雨 孟令锋 《电力机车与城轨车辆》 2024年第3期66-71,共6页
为实现欧盟各国铁路运营互联互通,欧盟铁路局组织制定了在世界范围内都影响较大的TSI系列标准。根据TSI要求,出口欧洲车辆的动态限界须满足EN 15273-2标准,但在实际出口项目执行过程中,部分车辆会出现超限的问题。文章针对EN 15273标准... 为实现欧盟各国铁路运营互联互通,欧盟铁路局组织制定了在世界范围内都影响较大的TSI系列标准。根据TSI要求,出口欧洲车辆的动态限界须满足EN 15273-2标准,但在实际出口项目执行过程中,部分车辆会出现超限的问题。文章针对EN 15273标准中车辆动态限界计算原理和方法展开系统研究,提炼和总结动态限界计算方法和项目执行中的注意事项,并进行详细案例计算说明,可帮助限界设计人员深入理解和快速掌握动态限界计算方法,提高限界计算准确性和效率。 展开更多
关键词 en 15273标准 车辆 动态限界 计算方法
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Functional Roux-en-Y Gastric Bypass (F-RYGB), with Preservation of Duodenal Access: Report of Two Revisional Cases of Sleeve Gastrectomy
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作者 Victor Ramos Mussa Dib Carlos Augusto Scussel Madalosso +3 位作者 Paulo Reis Esselin de Melo Rui Ribeiro Paula Volpe Carlos Eduardo Domene 《Surgical Science》 2024年第3期135-158,共24页
Objective: This case report aimed to demonstrate a possible neuromuscular effect of Latarjet nerves transection or truncal vagotomy, in association with sleeve gastrectomy plus antrojejunostomy, in order to reproduce ... Objective: This case report aimed to demonstrate a possible neuromuscular effect of Latarjet nerves transection or truncal vagotomy, in association with sleeve gastrectomy plus antrojejunostomy, in order to reproduce a Roux-en-Y gastric bypass (RYGB) mechanistic principles, in patients with previous Sleeve Gastrectomy (SG) who had had weight regain, with or without concomitant gastroesophageal reflux disease (GERD). Background: Sleeve gastrectomy (SG) is one of the most frequently performed bariatric operations worldwide. Nevertheless, weight regain and gastroesophageal reflux disease (GERD) have been consistently demonstrated, in association with this technique, which may require a revisional procedure. RYGB is an option in such a situation but, implies in gastrointestinal exclusions, which represents a shortcoming of this revision. Surpassing this inconvenient would be of great value for the patients. Methods: We describe herein two cases of SG revision for weight regain and GERD, with a follow-up of one year. Gastroesophageal reflux disease was evaluated by validated questionnaire, upper endoscopy, seriography, high resolution manometry (HRM) and impedance pHmetry (I-pHmetry), in the pre and postoperative periods. A re-Sleeve Gastrectomy with antrojejunal anastomosis was done in both cases, after informed consents. The Latarjet nerves were transected in one case, due to a bleeding in the left gastric vessels and a truncal vagotomy was required in the other, to appropriately treat an associated hiatal hernia. Results: In the postoperative evaluation it was observed a pyloric spasm in both cases, during seriography and endoscopy, kept until the one-year follow-up. There was unidirectional contrast flow to the gastrointestinal anastomosis, filling the jejunal limb, in radiologic contrast study. No contrast passed through the pylorus. Nonetheless, the duodenum was kept endoscopically accessible. In the one-year evaluation, weight loss was adequate and GERD resolution was obtained in both cases, confirmed by endoscopic and functional esophageal assessment, together with symptoms questionnaire. Conclusion: The association of Latarjet nerves sectioning or truncal vagotomy with re-sleeve gastrectomy plus gastrointestinal anastomosis (antrojejunal), in a revision for a failed sleeve, can represent a technical approach, to reproduce RYGB results, without exclusions and with duodenum endoscopic accessibility maintenance. It maybe could be applied for primary surgeries. Additional studies are necessary to confirm this hypothesis. 展开更多
关键词 Roux-en-Y Gastric Bypass Sleeve Gastrectomy Jejuno Gastric Bypass Vagus Nerve VAGOTOMY Bariatric Surgery
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基于EN 45545系列标准的动车组布线防火设计思考
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作者 李丰收 严钰甜 +3 位作者 曾星 杨朋 李洪德 李庭芳 《技术与市场》 2024年第3期63-66,71,共5页
EN 45545《铁路应用——机车车辆防火》是轨道交通行业一个关键的防火系列标准,旨在确保轨道交通车辆的内部材料和组件的耐火性能,以提供更高的安全性。基于EN 45545防火系列标准的要求,从布线部件的防火设计、基于火灾下运行能力的布... EN 45545《铁路应用——机车车辆防火》是轨道交通行业一个关键的防火系列标准,旨在确保轨道交通车辆的内部材料和组件的耐火性能,以提供更高的安全性。基于EN 45545防火系列标准的要求,从布线部件的防火设计、基于火灾下运行能力的布线设计以及防火布线防火隔断设计方面进行动车组布线设计,以期为轨道交通车辆布线防火设计提供参考。 展开更多
关键词 en45545 动车组布线 防火设计
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Giant dedifferentiated liposarcoma of the gastrocolic ligament:A case report
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作者 Assamoi Brou Fulgence Kassi Kacou Sebastien Yenon +4 位作者 Fian Marc Herve Kassi Adja Jacob Adjeme Khader Morel Diarra Cynthia Bombet-Kouame Marcellin Kouassi 《World Journal of Gastrointestinal Surgery》 SCIE 2023年第10期2376-2381,共6页
BACKGROUND Dedifferentiated liposarcoma(DDLS)has a worse prognosis and occurs most commonly in the retroperitoneal region and rarely in the intraperitoneal region.Histological diagnosis was revolutionized by the combi... BACKGROUND Dedifferentiated liposarcoma(DDLS)has a worse prognosis and occurs most commonly in the retroperitoneal region and rarely in the intraperitoneal region.Histological diagnosis was revolutionized by the combined contributions of histoimmuno-chemistry and molecular biology.Aside from surgery,there is no consensus on the optimal treatment for this chemoresistant cancer.CASE SUMMARY A thirty-year-old black female presented with a large painful abdominal mass occupying nearly the entire abdomen and progressive weight loss was admitted for surgery.Abdominal computed tomography showed a large heterogeneous mass of the mesentery that was sized 18 cm×16 cm in size and had heterogeneous contrast enhancement.During laparotomy,en bloc excision of the large and multilobulated gastrocolic ligament mass was performed.The initial postoperative histopathological diagnosis was undifferentiated sarcoma.Finally,the results of immunohistochemistry and molecular biology allowed us to confirm the diagnosis of DDLS.The tumour followed an aggressive evolution with diffuse metastasis,causing the death of the patient less than 5 mo after the operation.CONCLUSION Dedifferentiated liposarcomas are rare tumours that typically originate in the retroperitoneum but may arise in unexpected locations. 展开更多
关键词 Dedifferentiated liposarcoma Gastrocolic ligament mass en bloc excision IMMUNOHISTOCHEMISTRY Molecular biology Worse prognosis Case report
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食物袢与十二指肠残端固定预防Petersen疝及Roux-en-Y滞留综合征的临床效果分析
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作者 吴建忠 沈根海 +1 位作者 郎建华 黄维贤 《腹腔镜外科杂志》 2023年第4期262-265,280,共5页
目的:分析将食物袢固定于十二指肠残端以预防Petersen疝、Roux-en-Y滞留综合征发生的临床效果。方法:回顾分析2012年2月至2020年2月为254例患者行Roux-en-Y重建的根治性远端胃切除术的临床资料。对比Roux-en-Y重建后将食物袢固定于十二... 目的:分析将食物袢固定于十二指肠残端以预防Petersen疝、Roux-en-Y滞留综合征发生的临床效果。方法:回顾分析2012年2月至2020年2月为254例患者行Roux-en-Y重建的根治性远端胃切除术的临床资料。对比Roux-en-Y重建后将食物袢固定于十二指肠残端(固定组,n=95)与未固定(未固定组,n=159)Petersen疝、Roux-en-Y滞留综合征的发生率。结果:未固定组中7例(4.4%)发生Petersen疝,24例(15.1%)出现Roux-en-Y滞留综合征;固定组无一例发生Petersen疝(P=0.038),2例发生Roux-en-Y滞留综合征(P=0.001)。未固定组内,腹腔镜亚组的39例患者中3例发生Petersen疝;固定组内,腹腔镜亚组的50例患者均未发生Petersen疝;腹腔镜亚组内,固定亚组Petersen疝(P=0.047)、Roux-en-Y滞留综合征(P=0.004)的发生率低于未固定亚组。结论:Roux-en-Y重建后,将食物袢固定于十二指肠残端可有效减少Petersen疝、Roux-en-Y滞留综合征的发生。 展开更多
关键词 胃肿瘤 腹腔镜检查 吻合术 Roux-en-Y Petersen Roux-en-Y滞留综合征
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Two case reports of acute upper gastrointestinal bleeding from duodenal ulcers after Roux-en-Y gastric bypass surgery: Endoscopic diagnosis and therapy by single balloon or push enteroscopy after missed diagnosis by standard esophagogastroduodenoscopy 被引量:3
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作者 Seifeldin Hakim Srinivas R Rami Reddy +2 位作者 Mihaela Batke Gregg Polidori Mitchell S Cappell 《World Journal of Gastrointestinal Endoscopy》 CAS 2017年第10期521-528,共8页
The diagnosis and opportunity for endoscopic therapy of gastric or duodenal lesions may be missed at esophagogastroduodenoscopy(EGD) because of technical difficulty in intubating at EGD the postoperatively excluded st... The diagnosis and opportunity for endoscopic therapy of gastric or duodenal lesions may be missed at esophagogastroduodenoscopy(EGD) because of technical difficulty in intubating at EGD the postoperatively excluded stomach and proximal duodenum in patients status post Roux-en-Y gastric bypass(RYGB). Two cases are reported of acute upper gastrointestinal bleeding 10 or 11 years status postRYGB, performed for morbid obesity, in which the EGD was non-diagnostic due to failure to intubate the excluded stomach and proximal duodenum, whereas subsequent push enteroscopy or single balloon enteroscopy were diagnostic and revealed 4-cm-wide or 5-mm-wide bulbar ulcers and even permitted application of endoscopic therapy. These case reports suggest consideration of push enteroscopy, or single balloon enteroscopy, where available, in the endoscopic evaluation of acute UGI bleeding in patients status post RYGB surgery when the EGD was non-diagnostic because of failure to intubate these excluded segments. 展开更多
关键词 Morbid obesity Bariatric surgery Roux-en-Y gastric bypass surgery Upper gastrointestinal bleeding ESOPHAGOGASTRODUODenOSCOPY Push enteroscopy Single balloon enteroscopy Therapeutic endoscopy Double balloon enteroscopy
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腹腔镜辅助远端胃癌根治术不同Uncut Roux-en-y吻合方式对病人的疗效及对肿瘤标志物和预后的影响 被引量:1
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作者 刘炯 汪向飞 江斌 《临床外科杂志》 2023年第2期177-180,共4页
目的探讨不同Uncut Roux-en-y吻合方式对胃癌病人的疗效及对其检验指标和预后的影响。方法我院2018年3月~2021年2月收治的远端胃癌病人96例,均行腹腔镜辅助远端胃癌根治术,根据吻合方式分为两组,其中研究组46例,采用改良U-RY吻合术治疗... 目的探讨不同Uncut Roux-en-y吻合方式对胃癌病人的疗效及对其检验指标和预后的影响。方法我院2018年3月~2021年2月收治的远端胃癌病人96例,均行腹腔镜辅助远端胃癌根治术,根据吻合方式分为两组,其中研究组46例,采用改良U-RY吻合术治疗,对照组病人50例,采用U-RY吻合术治疗,比较两组病人的围术期指标(手术时间、术中出血量、首次通气时间、住院时间及术后第1天引流量)、手术前后肿瘤相关指标(CEA、CA19-9)、术后并发症及术后1年的预后情况。结果除术后第1天引流量外,研究组的其余指标(手术时间、术中出血量、首次通气时间和住院时间)优于对照组(P<0.05);术前两组的肿瘤相关指标(CA19-9、CEA)比较无明显差异(P>0.05),术后两组病人的肿瘤相关指标(CA19-9、CEA)均较术前降低,差异有统计学意义(P<0.05);研究组总并发症发生率比对照组低(8.7%vs 30.0%,P<0.05);术后1年,两组病人的生存率和复发率比较无明显差异(97.8%vs 96.0%,4.3%vs 6.0%,P>0.05)。结论腹腔镜辅助远端胃癌根治术中应用改良U-RY吻合术可显著缩短病人的手术时间,加快病人的康复速度,且可降低其术后并发症发生率,最终不影响病人的预后。 展开更多
关键词 胃癌 腹腔镜辅助远端胃癌根治术 非离断式Roux-en-Y 疗效 预后
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改良Warren吻合术与Roux-en-Y吻合术在小儿腹腔镜胆总管囊肿术中的临床对照研究
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作者 马仲福 赵成基 +6 位作者 曾永娟 陈亚惊 胡继科 李斌德 李刚 王文赟 杨爱玲 《兰州大学学报(医学版)》 2023年第9期52-56,共5页
目的比较腹腔镜先天性胆总管囊肿根治术中2种胆肠吻合方式的优劣,为临床选择不同术式提供理论依据。方法回顾性分析兰州大学第二医院2016年7月-2022年4月收治的117例先天性胆总管囊肿患者,按手术方式分为Roux-en-Y吻合组(63例)与改良War... 目的比较腹腔镜先天性胆总管囊肿根治术中2种胆肠吻合方式的优劣,为临床选择不同术式提供理论依据。方法回顾性分析兰州大学第二医院2016年7月-2022年4月收治的117例先天性胆总管囊肿患者,按手术方式分为Roux-en-Y吻合组(63例)与改良Warren吻合组(54例)。2组患者均行腹腔镜下胆总管囊肿根治性切除术,肠-肠吻合方式有Roux-en-Y式肠-肠吻合及改良Warren式肠-肠吻合。比较2组患者手术效果、术后效果及术后并发症等指标。结果2组患者手术时间、吻合时间、术后恢复排气排便时间、术后并发肠梗阻及反流性胆管炎方面差异均有统计学意义(P<0.05),而其余指标没有显示明显差异(P>0.05)。结论改良Warren吻合术较Roux-en-Y吻合术,具有手术时间短、吻合快、术后肠功能恢复快、防反流效果好等优点,且操作简便,不切断肠管,保证肠管电生理活动的连续性,适合在基层医院推广。 展开更多
关键词 ROUX-en-Y吻合术 改良Warren吻合术 小儿腹腔镜手术 先天性胆总管囊肿
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分数Ornstein-Uhlenbeck过程最小二乘估计改进的Berry-Esséen界
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作者 陈勇 古象盟 《数学物理学报(A辑)》 CSCD 北大核心 2023年第3期855-882,共28页
该文目的有二.一是得到了当Hurst参数H∈(0,1/2)时,分数布朗运动联系的Hilbert空间H中有界变差函数的一种新颖的内积计算公式.这个新公式基于有界变差函数的Lebesgue-Stieljes测度的一种分解以及Lebesgue-Stieljes测度的分部积分公式.... 该文目的有二.一是得到了当Hurst参数H∈(0,1/2)时,分数布朗运动联系的Hilbert空间H中有界变差函数的一种新颖的内积计算公式.这个新公式基于有界变差函数的Lebesgue-Stieljes测度的一种分解以及Lebesgue-Stieljes测度的分部积分公式.二是作为该公式的应用,通过寻找对称张量空间H^(⊙2)中二元函数fT(t,s)=e^(−θ|t−s|)1{0≤s,t≤T},其范数的平方做为T的函数当T→∞时的渐近线,改进了当H∈(1/4,1/2)时,分数Ornstein-Uhlenbeck过程漂移系数最小二乘估计的Berry-Esséen类上界.该文的渐近分析比Hu,Nualart,Zhou(2019)引理17的相应结论精细许多;该文改进的Berry-Esséen界是Chen,Li(2021)定理1.1相应结论的最佳改进.作为一个附产品,该文也给出上述渐近分析的另一个应用,分数Ornstein-Uhlenbeck过程漂移系数矩估计的Berry-Esséen类上界,其证明方法和Sottinen,Viitasaari(2018)命题4.1的方法显著不同. 展开更多
关键词 分数布朗运动 分数 ORNSTEIN-UHLenBECK 过程 Berry-Esséen类上界
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一类分数高斯噪声驱动的Ornstein-Uhlenbeck过程的参数估计:Hurst参数H∈(0,1/2)
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作者 陈勇 李英 +1 位作者 盛英 古象盟 《数学物理学报(A辑)》 CSCD 北大核心 2023年第5期1483-1518,共36页
Chen和Zhou(2021)研究了一类分数高斯过程(G_(t))_(t≥0)驱动的Ornstein-Uhlenbeck过程的参数估计问题,其中协方差函数R(t,s)=E[G_(t)G_(s)]的二阶混合偏导分解成两个部分:一个与分数布朗运动相同,另一个以(ts)^(H−1)为界,其中H∈(1/2,... Chen和Zhou(2021)研究了一类分数高斯过程(G_(t))_(t≥0)驱动的Ornstein-Uhlenbeck过程的参数估计问题,其中协方差函数R(t,s)=E[G_(t)G_(s)]的二阶混合偏导分解成两个部分:一个与分数布朗运动相同,另一个以(ts)^(H−1)为界,其中H∈(1/2,1).该文研究同一问题,但假设H∈(0,1/2).分数高斯过程联系的希尔伯特空间H当H∈(1/2,1)和H∈(0,1/2)时差异显著.该文的起点是这类高斯过程(G_(t))t≥0和分数布朗运动(B^(H)_(t))t≥0分别联系的希尔伯特空间H和H_(1)的内积之间的一种定量关系.该文得到漂移参数基于连续时间观测的最小二乘估计和矩估计的强相合性,其中H∈(0,1/2),及渐近正态性和Berry-Esséen类上界,其中H∈(0,3/8). 展开更多
关键词 分数布朗运动 四阶矩定理 ORNSTEIN-UHLenBECK 过程 分数高斯过程 Berry-Esséen 类上界
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Analyzing the Prebiotic Potential of Glucosamine for Targeting the Gut Microbiome Health
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作者 Pranav Pancham Divya Jindal +4 位作者 Archita Gupta Deepshikha Yadav Shriya Agarwal Saurabh Jha Manisha Singh 《Food and Nutrition Sciences》 CAS 2023年第2期119-134,共16页
Recognizing the composition and modulation of the microbiome, a viable therapeutic tool for multi-targeted therapy is a new strategy that has recently been explored. Glucosamine (GS) is being studied for its prebiotic... Recognizing the composition and modulation of the microbiome, a viable therapeutic tool for multi-targeted therapy is a new strategy that has recently been explored. Glucosamine (GS) is being studied for its prebiotic potential in addition to being the most abundant and naturally occurring amino monosaccharide. The current study focuses on glucosamine’s prebiotic potential by assessing the stability of various GS concentrations (1% - 5%) in the gastrointestinal tract (GIT) and its ability to be fermented by the gut microbiota. The results showed that GS stimulated the most growth in L. acidophilus even after a longer incubation time than B. bifidum and L. acidophilus growth was concentration-dependent, with maximum growth at 3% with a simultaneous decrease in pH (5.6 - 1.7). The decrease in GS concentration with time also represented the growth of bacterial species, demonstrating the species’ utilization of GS. Furthermore, at 3%, GS also represented the prebiotic index of 1.9. In addition, the concentration of GS in various simulated GIT fluids was estimated in both fast and fed conditions to examine GS stability at various levels in the gut. The results showed that GS remained unaffected and non-digestible in all of the simulated GIT fluids (salivary, gastric, intestinal, and colonic), but there was a slight decrease in GS concentration (2.8%) in the fasted state of gastric fluid due to low pH levels (1.6). As a result, the findings are conclusive and suggest that GS possesses prebiotic properties. 展开更多
关键词 MICROBIOME enteric Nervous System (enS) Prebiotic Index Hexosamine Biosynthetic Pathway (HBP) Vagal Afferents Phosphotransferase System
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腹腔镜非离断Roux-en-Y吻合远端胃癌根治术治疗T_(1~4)aN_(0~3)M_(0)胃癌的临床研究
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作者 童永康 忽维维 吴培华 《海南医学》 CAS 2023年第24期3568-3572,共5页
目的观察腹腔镜非离断(Roux-en-Y)吻合远端胃癌根治术治疗T_(1~4)aN_(0~3)M_(0)胃癌的临床疗效,并探讨其对患者生活质量的影响。方法回顾性分析2019年5月至2022年7月宝鸡高新医院普通外科收治的80例T_(1~4)aN_(0~3)M_(0)胃癌患者的临床... 目的观察腹腔镜非离断(Roux-en-Y)吻合远端胃癌根治术治疗T_(1~4)aN_(0~3)M_(0)胃癌的临床疗效,并探讨其对患者生活质量的影响。方法回顾性分析2019年5月至2022年7月宝鸡高新医院普通外科收治的80例T_(1~4)aN_(0~3)M_(0)胃癌患者的临床资料,根据手术方式不同分组,其中43例接受腹腔镜非离断Roux-en-Y吻合远端胃癌根治术治疗者纳入非离断组,37例接受腹腔镜传统Roux-en-Y吻合远端胃癌根治术治疗者纳入传统组。比较两组患者的手术指标、手术前后胃液pH值、生活质量及并发症发生情况。结果非离断组患者的半流质进食时间及手术时间分别为(4.83±1.64)d、(205.36±30.56)min,明显短于传统组的(8.10±1.86)d、(237.81±32.32)min,而出血量为(62.57±31.96)mL,明显少于传统组的(125.47±48.93)mL,差异均有统计学意义(P<0.05);非离断组患者术后5 d胃液pH值为6.12±0.41,明显高于传统组的5.92±0.40,差异有统计学意义(P<0.05);两组患者术后各项生活质量评分均较术前升高,且非离断组患者术后的各项评分升高幅度明显大于传统组,差异均有统计学意义(P<0.05);非离断组患者术后并发症总发生率为16.28%。略低于传统组患者的23.68%,但差异无统计学意义(P>0.05)。结论与腹腔镜传统Roux-en-Y吻合远端胃癌根治术比较,采用腹腔镜非离断Roux-en-Y吻合远端胃癌根治术治疗T_(1~4)aN_(0~3)M_(0)胃癌,手术时间明显缩短,术中出血量更少,患者生活质量显著提高。 展开更多
关键词 胃癌 非离断Roux-en-Y吻合远端胃癌根治术 传统Roux-en-Y吻合远端胃癌根治术 治疗效果 生活质量
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基于YOLOv5-en算法的草莓采摘机器人目标检测技术 被引量:1
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作者 高云茜 邓三鹏 《实验技术与管理》 CAS 北大核心 2023年第10期178-183,216,共7页
为实现草莓采摘机器人在温室中对草莓的快速、精确检测,该文提出一种YOLOv5-en算法。在原有YOLOv5基础上,首先对原始主干进行网络卷积操作并加入CBAM模块;其次,引入BiFPN模块进行多尺度特征融合;然后,使用直方图均化算法和Mosaic数据增... 为实现草莓采摘机器人在温室中对草莓的快速、精确检测,该文提出一种YOLOv5-en算法。在原有YOLOv5基础上,首先对原始主干进行网络卷积操作并加入CBAM模块;其次,引入BiFPN模块进行多尺度特征融合;然后,使用直方图均化算法和Mosaic数据增强进行目标检测数据预处理;最后,优化K-means算法对训练数据集聚类分析,同时使用Focal loss损失函数构建YOLOv5-en目标检测网络。通过对比试验得出:与YOLOv5、Faster-RCNN ResNet101和Faster-RCNN VGG16模型相比,YOLOv5-en的mAP分别提升了3.41%、17.85%和14.40%,可达94.36%。通过采摘机器人模拟环境检测验证了该模型的可行性,且达到了应用水平,可为采摘机器人实时小目标检测提供支撑。 展开更多
关键词 YOLOv5-en CBAM BiFPN 采摘机器人
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HBFNEnKF混合同化方法设计及检验 被引量:4
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作者 朱浩楠 闵锦忠 杜宁珠 《大气科学》 CSCD 北大核心 2016年第5期995-1008,共14页
基于前后张驰逼近(Back and Forth Nudging,简称BFN)和集合卡尔曼滤波(En KF)方法,构建了一种新的同化方法 HBFNEn KF(Hybrid Back and Forth Nudging En KF)混合同化方法,并将此同化系统分别与通道浅水模式(shallow water model)和全... 基于前后张驰逼近(Back and Forth Nudging,简称BFN)和集合卡尔曼滤波(En KF)方法,构建了一种新的同化方法 HBFNEn KF(Hybrid Back and Forth Nudging En KF)混合同化方法,并将此同化系统分别与通道浅水模式(shallow water model)和全球浅水模式对接,检验了HBFNEn KF同化方法的有效性。同时,对比了集合均方根滤波(En SRF)、HNEn KF(Hybrid Nudging En KF)、HBFNEn KF三种方法在有误差模式中的同化效果。试验结果表明:HBFNEn KF同化方法保留了HNEn KF方法的同化连续性,解决了En KF同化不连续不平滑的问题,同时还有着更快的收敛速度;当采用单变量分析试验时,HBFNEn KF方法的优势最为明显,表明HBFNEn KF能够较好地保持不同模式变量间的平衡。此外,增量场尺度分析结果表明:相比En SRF,HBFNEn KF在大尺度范围有更好的同化效果,同时能够避免在中小尺度范围内出现大量的虚假增量。 展开更多
关键词 资料同化 Hybrid Back and FORTH Nudging en KF (HBFNen KF) enSEMBLE Square-Root Fiter (en SRF) 浅水模式
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改良和常规胃空肠Roux-en-Y吻合术在胃肠手术中的应用效果对比
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作者 姜常龙 李宏伟 《医师在线》 2023年第8期50-53,共4页
目的探讨改良和常规胃空肠Roux-en-Y吻合术在胃肠手术中的应用效果。方法回顾性分析2021年1月~2022年12月我院收治的76例胃肠手术患者,按照不同的手术方法分为对照组及观察组。对照组38例行常规胃空肠Roux-en-Y吻合术,观察组38例行改良... 目的探讨改良和常规胃空肠Roux-en-Y吻合术在胃肠手术中的应用效果。方法回顾性分析2021年1月~2022年12月我院收治的76例胃肠手术患者,按照不同的手术方法分为对照组及观察组。对照组38例行常规胃空肠Roux-en-Y吻合术,观察组38例行改良胃空肠Roux-en-Y吻合术。比较两组手术指标、术后疼痛评分和并发症。结果对照组的术后并发症发生率为28.95%,观察组的术后并发症发生率为7.89%,观察组明显低于对照组(P<0.05)。与对照组相比,观察组术中出血量、手术时间、住院时间均明显更少(P<0.05)。与对照组相比,观察组术后6 h、12 h、18 h、24 h时的视觉模拟评分法(VAS)评分明显更低(P<0.05)。结论改良胃空肠Roux-en-Y吻合术可改善胃肠疾病患者的术后机体疼痛,减少术后并发症,加快康复。 展开更多
关键词 胃肠手术 常规胃空肠Roux-en-Y吻合术 改良胃空肠Roux-en-Y吻合术 应用效果
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三维超声速后掠翼转捩的eN-神经网络模型预测
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作者 于晟浩 袁吉森 +2 位作者 高亮杰 钱战森 李椿萱 《力学学报》 EI CAS CSCD 北大核心 2023年第6期1236-1246,共11页
为提高三维超声速边界层转捩预测的计算效率,使用神经网络模型替代线性稳定性分析的过程,发展了一种适用于三维可压缩边界层转捩高效预测的神经网络模型方法.通过对线性稳定性分析方法及超声速后掠翼流场特征的研究,提出适用于超声速后... 为提高三维超声速边界层转捩预测的计算效率,使用神经网络模型替代线性稳定性分析的过程,发展了一种适用于三维可压缩边界层转捩高效预测的神经网络模型方法.通过对线性稳定性分析方法及超声速后掠翼流场特征的研究,提出适用于超声速后掠翼流动转捩预测的神经网络模型特征参数,使用系列超声速后掠钝板模型作为样本集,建立了eN-神经网络模型.以三维超声速大后掠等直机翼标准模型作为测试集,分析各输入参数的敏感性,并对比eN-神经网络模型与传统稳定性分析方法的计算结果及效率,验证了本方法的准确性与高效性. 展开更多
关键词 转捩预测 en方法 神经网络 超声速 后掠翼
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