Laparoscopic pancreatic duct incision and stone removal and T-type tube drainage for pancreatic duct stone: A case report and review of literature

To study a more micro-invasive procedure for patients having pancreatic duct stones(PDS).Till now,there has been no report of laparoscopic pancreatic duct incision and stone removal and T-type tube drainage for PDS in the English literature.An 82-year-old man suffered from subxiphoid pain associated with a dilated pancreatic duct(7 mm)containing one stone,but without a mass in the head of the pancreas.Laparoscopic pancreatic duct incision,stone removal,and T-type tube drainage were successfully performed without intraoperative or postoperative complications.An uneventful operation was performed with laparoscopically completed procedures in 160 min.The intraoperative loss of blood was around 50 mL.After patient a discharge on day 11,complete relief from the subxiphoid pain was reported at a follow-up visit 15 mo later.Laparoscopic pancreatic duct incision with stone removal and T-type tube drainage is applicable in carefully selected patients and can be effectively and safely used for the treatment of the abdominal pain of chronic pancreatitis.

The propagation law and analysis of gas explosion in U type duct

In order to explore the propagation law of gas explosion in U type laneways,the propagation law of flame and shock wave in U type duct were experimentally and theoret- ically investigated.It is shown that the shock wave takes on the complicated stress state and the flame takes on complicated change rules in the U type duct.The propagation process of gas explosion in bend duct is the mutual action of explosion wave,flame and complicate flow,the destruction in bend surface is especially serious.In the mine exploita- tion and laneway design,the bend laneway should be avoided,especially continuous bend laneway.

Resistance Characteristics of Hydraulic Oil through Isodiametric T-type Duct with Sharp Corners

Rational determination and reduction of local energy loss of oil flow at pipe junctions are of important significance to improve hydraulic pipeline＇s work efficiency, especially for complex hydraulic pipeline connected by isodiametric T-type ducts with sharp comers to get combined and divided flow. From this point of view, the formulae of resistance loss for combined flow and divided flow through isodiametric T-type duct with sharp comers as well as the correlations of resistance loss coefficients in the branches of the duct are derived using energy method. On this basis, resistance characteristics of hydraulic oil in the duct are obtained by numerical simulation of different flow modes, which are commonly applied in hydraulic pipelines, using computational fluid dynamics （CFD） method, and the reasons for the resistance loss are analyzed based on the pressure change mechanism in the flow field. A part of simulation results was validated with the reference data. The research shows that for combined flows the resistance loss of symmetrical is lower than that of unsymmetrical to obtain low speed in common branch, but to gain high speed is quite the contrary, for divided flows, the symmetrical is always a reasonable choice to reduce resistance loss. These conclusions can be applied to optimize the design of hydraulic pipeline.

Intraductal papillary bile duct adenocarcinoma and gastrointestinal stromal tumor in a case of neurofibromatosis type 1

We report our experience with a synchronous case of gastrointestinal stromal tumor(GIST) and intraductal papillary neoplasm of the bile duct(IPNB) in anelderly woman with neurofibromatosis type 1(NF-1). A 72-year-old woman presented with a 2-mo history of right upper abdominal pain unrelated to diet and indigestion. Fourteen years earlier, she had been diagnosed with NF-1, which manifested as café au lait spots and multiple nodules on the skin. Computed tomography(CT) revealed a multilocular low-density mass with septation, and mural nodules in the right hepatic lobe, as well as a 1.7-cm-sized well-demarcated enhancing mass in the third portion of the duodenum. The patient subsequently underwent right hepatectomy and duodenal wedge resection. We present here the first report of a case involving a synchronous IPNB and GIST in a patient with NF-1. Our findings demonstrate the possibility of various tumors in NF-1 patients and the importance of diagnosis at an early

Differences between main-duct and branch-duct intraductal papillary mucinous neoplasms of the pancreas

In the last decade,intraductal papillary mucinous neoplasms(IPMNs) have become commonly diagnosed.From a morphological standpoint,they are classified in main-duct IPMNs(MD-IPMNs) and branch-duct IPMNs(BD-IPMNs),depending on the type of involvement of the pancreatic ductal system by the neoplasm.Despite the fact that our understanding of their natural history is still incomplete,recent data indicate that MD-IPMNs and BD-IPMNs show significant differences in terms of biological behaviour with MD-IPMNs at higher risk of malignant degeneration.In the present paper,clinical and epidemiological characteristics,rates of malignancy and the natural history of MD-IPMNs and BD-IPMNs are analyzed.The profile of IPMNs involving both the main pancreatic duct and its side branches(combined-IPMNs) are also discussed.Finally,general recommendations for management based on these differences are given.

Preventive effects of autologous bone marrow mononuclear cell implantation on intrahepatic ischemic-type biliary lesion in rabbits

BACKGROUND: The ischemic-type biliary lesion (ITBL) is one of the most serious biliary complications of liver transplantation. This study aimed to investigate the effects of autologous bone marrow mononuclear cell (BM-MNC) implantation on neovascularization and the prevention of intrahepatic ITBL in a rabbit model. METHODS: The rabbits were divided into control, experimental model, and cell implantation groups, with 10 in each group. The model of intrahepatic ITBL was established by clamping the hepatic artery and common bile duct. Autologous BM-MNCs were isolated from the tibial plateau by density gradient centrifugation and were implanted through the common hepatic artery. Changes in such biochemical markers as aspartate aminotransferase, alanine aminotransferase, alkaline phosphatase, gamma-glutamyltranspeptidase, total bilirubin and direct bilirubin were measured. Four weeks after operation, cholangiography, histopathological manifestations, differentiation of BM-MNCs, microvessel density and the expression of vascular endothelial growth factor were assessed. RESULTS: Compared with the experimental model group, the BM-MNC implantation group showed superiority in the time to recover normal biochemistry. The microvessel density and vascular endothelial growth factor expression of the implantation group were significantly higher than those of the control and experimental model groups. The ITBL in the experimental model group was more severe than that in the implantation group and fewer new capillary blood vessels occurred around it. CONCLUSIONS: Implanted autologous BM-MNCs can differentiate into vascular endothelial cells, promote neovascularization and improve the blood supply to the ischemic bile duct, and this provides a new way to diminish or prevent intrahepatic ITBL after liver transplantation. (Hepatobiliary Pancreat Dis Int 2010; 9:593-599)

Conversion surgery after gemcitabine and cisplatin plus durvalumab for advanced intrahepatic cholangiocarcinoma:A case report

BACKGROUND The combination of immune checkpoint inhibitors and chemotherapy has shown promising results for the treatment of advanced biliary tract cancer(BTC).Based on the results of the TOPAZ-1 trial,a gemcitabine and cisplatin plus durvalumab(GCD)regimen was recently approved as first-line therapy for patients with advanced BTC.However,post-GCD conversion surgery has not been previously studied.Herein,we describe a case of advanced intrahepatic cholangiocarcinoma(ICC)successfully treated with radical surgery after GCD.CASE SUMMARY A 65-year-old female diagnosed with advanced ICC with periductal infiltration into the hepatic hilum underwent eight cycles of GCD,followed by durvalumab maintenance treatment,with mild adverse events.Partial response was obtained.Subsequently,a conversion surgery with extended left hepatectomy and bile duct resection was performed.The resection margins were negative,and the pathological diagnosis was compatible with small duct type ICC.The patient remained disease-free for 8 months without adjuvant chemotherapy.CONCLUSION We describe the case of a patient who received successful conversion surgery after GCD treatment for advanced ICC.

风道结构改善货架式冷库热环境的数值模拟研究

本文采用数值模拟的方法探索风道结构对货架式冷库热环境的影响,分析风道结构各因素对热环境评价指标的影响程度。研究结果显示,在本文所设计的12种工况中,风道结构直接影响冷库温湿度分布均匀性和能量利用率,温度不均匀系数、相对湿度不均匀系数随着无因次风道宽度增加而下降,随着开口率的增加而减小。采用极差分析法和方差分析法判断多种因素对评价指标的影响显著程度,并根据综合平衡法得到最优工况,即第13种工况:无因次风道宽度为0.5,开口率为11.8%,该工况下温度及相对湿度不均匀系数分别下降为0.09及0.016、能量利用系数提高至1.68,可显著改善货架式冷库热环境。

核电站孔道式蒸汽发生器热工分析及换热性能研究

为满足核电站提高蒸汽参数以获得更好的发电效率及经济性的发展需求,提出了一种适用于高温气冷堆超超临界参数下的孔道式蒸汽发生器。介绍了孔道式蒸汽发生器结构的主要特点,分析了该结构在换热性能、运行安全、生产成本等方面的优势。通过建立理论计算模型,对该蒸汽发生器采用直流逆流换热方式下的轴向、径向、准三维温度分布等参数进行了热工分析及换热性能研究。计算结果表明:该孔道式蒸汽发生器以对流传热及热传导的换热方式为主,温度分布分段明显,换热性能优异,符合相关换热要求。该研究可为核电站蒸汽发生器的设计及研发提供参考。

输卵管卵巢脓肿特征性CT表现的分析

目的探讨输卵管卵巢脓肿在MSCT检查中对诊断有价值的特征性表现。方法选取经手术病理证实的输卵管卵巢脓肿患者56例,术前均行CT增强扫描检查,分析临床及影像学资料。结果输卵管卵巢脓肿患者中单独右侧发病28例(50%),单独左侧发病18例(31.14%),双侧发病10例(17.85%)。管道型输卵巢卵巢脓肿26例(46.43%),串珠型为16例(28.57%),多囊型为12例(21.42%),单囊型2例(3.57%)。各种类型的输卵管卵巢脓肿灶的短径比较,差异有统计学意义(P=0.016),长径/短径的比较差异有统计学意义(P=0.024),线性囊灶出现于60.71%的输卵管卵巢脓肿,在管道型与其他各分型中所占比例差异有统计学意义(P=0.014)。输卵管卵巢脓肿的囊壁厚度介于0.21~0.35 cm之间,增强扫描厚壁及分隔可见中重度强化,静脉期达到峰值,平均强化程度为43~51HU。结论通过对输卵巢卵巢脓肿CT征象的观察,管道型结构和线性囊灶的出现可提示诊断输卵管卵巢脓肿,对提高影像科医师的准确诊断有一定帮助。

弯曲设计在涡轮一体化过渡段中的气动效果分析

为提升某对转涡轮过渡段性能,并研究叶片弯曲技术在过渡段中的气动效果,对某一体化设计涡轮过渡段进行数值模拟。对过渡段内支板及气动导向叶片进行弯曲设计,控制弯曲叶高50%,设计正弯、反弯、J型、反J型四种弯曲形式,弯角变化范围10°~20°,通过对比分析不同的叶片弯曲方案,初步探讨叶片弯曲在一体化过渡段内控制二次流动、减小损失的机理。结果表明:过渡段中主要损失区域集中在支板和气动导向叶片吸力面尾缘角区,采用J型设计能够有效改善叶片表面压力分布,大幅缩小高损失区范围,优化主流流动,20°弯角J型设计能够使通道内能量损失系数相对降低7.4%,对控制一体化过渡段流场内二次流动起到改善效果。

UHPC预制轨顶风道装配化研究

为提高轨顶风道现场施工的便捷性和施工质量,结合广州地铁10号线的实际情况,提出一种装配式轨顶风道的装配方案。结合使用超高性能混凝土(UHPC),利用其超高的力学性能和耐久性能,减少轨顶风道后期的相关维护。结果表明:本文所提出的装配式轨顶风道设计方案安全可靠,施工工艺合理,UHPC在预制风道中的使用,提高了风道的相关力学性能,降低了后期维护成本。

腹腔镜胆囊切除术中胆管损伤的原因、类型和处理

目的探讨腹腔镜胆囊切除术(LC)中胆管损伤的原因、类型及处理措施。方法回顾分析本科1993年3月￣2004年7月腹腔镜胆囊切除术的临床资料。结果LC9200例中,胆管损伤11例,发生率0.12%。其中急诊LC475例,急诊率5.16%,无一胆管损伤;中转开腹193例,中转率为2.09%,中转开腹胆管损伤2例,损伤率1.05%。胆管损伤术中发现8例、术后诊断3例;胆管修补(端端吻合)+T管支撑引流6例、胆肠Roux-en-y吻合4例,腹腔穿刺+鼻胆管引流1例(ENBD);再次胆道手术1例,再手术率9.09%。结论遵循辨-切-辨手术程序是避免LC胆管损伤的关键;严格掌握LC和急诊LC的适应证,果断及时中转开腹是避免胆管损伤的重要手段;及时发现实时处理胆管损伤能有效降低胆管损伤的再手术率。

B超、T管造影及电子胆道镜对胆管残余结石的诊断价值

目的探讨胆道术后残余结石的诊断方法。方法回顾分析167例进行胆道镜检查和取石病人的B超、T管造影和胆道镜检查记录,对3种诊断方法的诊断准确率和诊断效率进行比较分析。结果B超、T管造影和胆道镜三者的诊断准确率、假阳性率及假阴性率分别为84.5,5.6,9.9,74.6,1.4,23.9,98.6,0和1.4%。但电子胆道镜与B超(P=0.791)、T管造影(P=0.457)的诊断效率差异性比较无统计学意义。结论三种检查方法各有优点,B超能提供结石位置与数量、胆管扩张情况,T管造影能提供有无残余结石、胆管狭窄、胆道引流是否通畅,胆道镜能直接了解结石、肿瘤、狭窄、炎症、出血和发现B超、T管造影不能发现的结石,并可同步进行取石。三者在胆道术后残余结石的诊断过程中发挥各自优势,不能相互替代,建议胆道结石的术后病人常规进行三者检查,在最大程度上降低胆管结石残余率。

海上低空大气波导及其应用综述

低空大气波导对电波传播和探测通信系统等具有重要影响,研究大气波导环境和开发其应用系统具有重要的科学意义和应用价值。本文以工程应用为目标,简要概括了海上蒸发波导、表面波导和悬空波导的调查方法和主要研究进展,以及基于大气波导环境的电波传播评估系统。蒸发波导调查,一般通过近海面气象要素廓线进行间接的观测,在工程中多利用相似理论计算大气折射率廓线,该方法已集成到许多针对电波传播效应开发的软件中。表面和悬空波导调查,大多采用气象探空方法进行观测,近年来对该类大气波导环境的观测方法,由通过天气图、卫星云图等进行定量分析和估算,逐渐发展为中尺度天气数值式精确确定,在工程中更倾向于海气耦合数值模式,如美国的COAMPS业务系统。关于大气波导传播效应的主要理论有几何光学理论、波导模理论和抛物型方程,其中抛物型方程理论应用较多。最后指出大气波导研究在工程方面努力的方向,即结合中尺度数值模式和电波传播模式发展三维可视化系统,准确可靠地提供电波环境信息和预测预报,更好地为经济和国防建设服务。

复合型人工胆管实验研究

目的筛选性能优异的非降解型材料,制备复合型人工胆管,观察其植入动物体内后的生物学特性,分析作为胆管替代物的可行性。方法内层采用聚四氟乙烯材料,外层采用医用级尼龙纤维编织,氟橡胶涂覆,制备复合型人工胆管。将6只实验猪的胆总管各切除20 mm,植入人工胆管,90 d后取出行组织学及电镜检测。结果实验猪术后均无胆漏及黄疸。肝功能:术后2、8、12周ALT、AST、TBil及DBil指标均正常。90 d后解剖:腹腔无粘连、无胆漏,近端胆管无扩张,肝脏色泽质地正常。人工胆管外层为纤维组织均匀包裹,无明显炎性改变,管腔通畅,管内壁光洁,无沉淀物附着。透射电镜检测:胆管周围组织中可见胶原纤维、纤维细胞、毛细血管和排列整齐的胆管上皮细胞,各细胞器结构正常,未见中性粒、淋巴、单核等炎性细胞。扫描电镜示:人工胆管从动物体内取出后与术前人工胆管对比无明显改变。结论人工胆管采用复合型结构为一种新的制作理念,便于胆管植入的缝合与支撑,预防胆漏与狭窄。实验证实复合型人工胆管组织相容性好,具有作为胆管替代物的可行性,有进一步研究的价值。

超声与CT检查对肝胆管结石并发肝胆管癌的诊断价值

目的:观察超声对肝胆管结石合并肝胆管癌的诊断率,为肝胆疾病的临床诊断提供可借鉴的方法。方法:选取2011年1月至2012年1月在我院肝胆外科就诊的肝胆管结石合并肝胆管癌患者60例,随机分为观察组和对照组。观察组30例患者于手术前行B超检查,对照组30例患者行CT检查,比较两组临床确诊率。结果:观察组确诊18例,确诊率为60.0%;胆管内乳头状癌4例,诊出率为66.7%;胆管壁狭窄型癌2例,诊出率为50%;对照组确诊22例,确诊率为73.3%;胆管内乳头状癌3例,诊出率为50%;未诊出胆管壁狭窄型癌病例。对照组确诊率优于观察组,差异具有意义(P<0.05)。观察组胆管内乳头状癌及胆管壁狭窄型癌的诊出率显著优于对照组,差异具有统计学意义(P<0.05)。结论:B超和CT在临床上均可诊断胆管结石合并肝胆管癌,但B超的临床确诊率优于CT,值得推广应用。

医源性胆管损伤分型及优化处理规范探讨

目的研讨一种科学的胆管损伤分型标准,用以规范胆管损伤的诊断并指导临床治疗。方法回顾分析52例胆管损伤的临床资料,研究其损伤特点、处理方式及治疗效果,并总结复习相关文献。结果本组病例根据不同的胆管损伤类型,指导治疗方案,对术中及术后不同时期发现的胆管损伤,分别行一期胆道修复、外引流或胆肠吻合等不同方法合理处理,术后随访,发生胆道狭窄8例,11例常伴有右上腹不适,33例随访期恢复良好。结论胆管损伤的疗效受损伤类型和恰当的处理方案等因素的影响。科学合理的胆管损伤分型和基于该分型而采取的处置原则,能减少并发症及提高治疗效果,可以作为胆管损伤后规范治疗的参考。

以胆道感染为主要临床表现的小胆管型原发性硬化性胆管炎1例报告

1病例资料 患者女性,30岁,因＂慢性肝炎2年,右上腹疼痛伴尿黄1d＂于2017年3月24日入本院。患者自2015年2月至本次发病期间曾反复多次因右上腹疼痛伴肝功能异常住院治疗,均经抗生素抗感染及常规保肝治疗后好转,

儿童胆道扩张症与胰胆管合流异常的相关性

目的通过回顾性分析先天性胆道扩张症(CBD)临床病例资料,比较合并胰胆管合流异常(PBM)与无合流异常病例的临床特征之间的差异,探讨PBM以及共同管长度与CBD的发病、临床症状、相关实验室检查结果的相关性,为CBD的发病机理和诊断治疗提供新的理论依据。方法回顾性总结2017年1月至2019年12月首都医科大学附属北京儿童医院普外科收治的胆道扩张症病例临床资料,83例胆道扩张症患儿纳入研究,以MRCP中胰胆管共同管长度为分组标准,分为合流异常组(共同管长度≥5 mm,n=47)与非合流异常组(共同管长度<5 mm,n=36),研究指标包括发病年龄、性别、临床症状、相关实验室检查、共同管长度、胆道结石以及胆总管囊肿大小,研究结果采用非参数检验和χ^(2)检验。结果在临床症状中,发热、黄疸、白色大便及胆道结石两组间无统计学差异(P>0.05),腹痛症状合流异常组多于无合流组(P<0.05);实验室检查结果AST、ALT、TBIL、DBIL及IBIL两组间无统计学差异(P>0.05),血清淀粉酶检测合流异常组高于无合流异常组(P<0.05);合流异常组胆总管呈囊肿型32例(38.6%),梭型15例(18.1%),无合流异常组胆总管呈囊肿型26例(31.3%),梭型10例(12.0%),两组间无统计学差异(P>0.05),但胆总管囊肿体积合流异常组小于无合流异常组(P=0.02)。结论先天性胆道扩张症合并胰胆管合流异常的患儿出现腹痛症状较早、较严重,同时血清淀粉酶较高,合并胰腺炎较常见,故易于做出早期诊断,可能也是本组胆总管囊肿体积较小的原因。本研究胰胆管共同管长短与先天性胆道扩张症的临床症状、肝功能、胆红素及血清淀粉酶等水平无明确相关性,故不能单纯以胰胆管共同管长度判断病情轻重。