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Appendicitis combined with Meckel’s diverticulum obstruction, perforation, and inflammation in children: Three case reports
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作者 Yi-Meng Sun Wang Xin +4 位作者 Yu-Fang Liu Zhe-Ming Guan Hao-Wen Du Ning-Ning Sun Yong-Dong Liu 《World Journal of Clinical Cases》 SCIE 2024年第4期865-871,共7页
BACKGROUND Meckel’s diverticulum is a common congenital malformation of the small intestine,with the three most common complications being obstruction,per-foration,and inflammation.To date,only a few cases have been ... BACKGROUND Meckel’s diverticulum is a common congenital malformation of the small intestine,with the three most common complications being obstruction,per-foration,and inflammation.To date,only a few cases have been reported world-wide.In children,the clinical symptoms are similar to appendicitis.As most of the imaging features are nonspecific,the preoperative diagnosis is not precise.In addition,the clinical characteristics are highly similar to pediatric acute appendicitis,thus special attention is necessary to distinguish Meckel’s diver-ticulum from pediatric appendicitis.Patients with poor disease control should undergo laparoscopic exploration to avoid serious complications,including intestinal necrosis,intestinal perforation and gastrointestinal bleeding.CASE SUMMARY This report presents three cases of appendicitis in children combined with intestinal obstruction,which was caused by fibrous bands(ligaments)arising from the top part of Meckel's diverticulum,diverticular perforation,and diver-ticular inflammation.All three patients,aged 11-12 years,had acute appendicitis as their initial clinical presentation.All were treated by laparoscopic surgery with a favorable outcome.A complete dataset including clinical presentation,dia-gnostic imaging,surgical information,and histopathologic findings was also provided.CONCLUSION Preoperative diagnosis of Meckel’s diverticulum and its complications is challenging because its clinical signs and complications are similar to those of appendicitis in children.Laparoscopy combined with laparotomy is useful for diagnosis and treatment. 展开更多
关键词 meckels diverticulum Complications Intestinal obstruction PERFORATION Appendicitis in children Mesodiverticular band LIGAMENT Diverticular disease Case report
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Single-center retrospective study of the diagnostic value of doubleballoon enteroscopy in Meckel’s diverticulum with bleeding
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作者 Tian He Chao Yang +10 位作者 Jing Wang Ji-Sheng Zhong Ai-Hua Li Ya-Jing Yin Li-Ling Luo Chun-Mei Rao Nian-Fen Mao Qiang Guo Zan Zuo Wen Zhang Ping Wan 《World Journal of Gastrointestinal Surgery》 SCIE 2024年第4期1043-1054,共12页
BACKGROUND The study aimed to analyze the characteristic clinical manifestations of patients with intestinal disease Meckel’s diverticulum(MD)complicated by digestive tract hemorrhage.Moreover,we aimed to evaluate th... BACKGROUND The study aimed to analyze the characteristic clinical manifestations of patients with intestinal disease Meckel’s diverticulum(MD)complicated by digestive tract hemorrhage.Moreover,we aimed to evaluate the value of double-balloon enteroscopy(DBE)in MD diagnosis and the prognosis after laparoscopic diverticula resection.AIM To evaluate the value of DBE in the diagnosis and the prognosis after laparoscopic diverticula resection for MD with bleeding.METHODS The study retrospectively analyzed relevant data from 84 MD patients treated between January 2015 and March 2022 and recorded their clinical manifestations,auxiliary examination,and follow-up after laparoscopic resection of diverticula.RESULTS(1)Among 84 MD patients complicated with hemorrhage,77 were male,and 7 were female with an average age of 31.31±10.75 years.The incidence was higher in men than in women of different ages;(2)Among the 84 MD patients,65(78.40%)had defecated dark red stools,and 50(58.80%)had no accompanying symptoms during bleeding,indicating that most MD bleeding appeared a dark red stool without accompanying symptoms;(3)The shock index of 71 patients(85.20%)was<1,suggesting that the blood loss of most MD patients was less than 20%–30%,and only a few patients had a blood loss of>30%;(4)The DBE-positive rate was 100%(54/54),99mTcpertechnetate-positive scanning rate was 78%(35/45)compared with capsule endoscopy(36%)and small intestine computed tomography(19%).These results suggest that DBE and 99mTc-pertechnetate scans had significant advantages in diagnosing MD and bleeding,especially DBE was a highly precise examination method in MD diagnosis;(5)A total of 54 MD patients with hemorrhage underwent DBE examination before surgery.DBE endoscopy revealed many mucosal manifestations including normal appearance,inflammatory changes,ulcerative changes,diverticulum inversion,and nodular hyperplasia,with ulcerative changes being the most common(53.70%).This suggests that diverticular mucosal ulcer was the main cause of MD and bleeding;and(6)Laparoscopic dissection of diverticulae was performed in 76 patients,The patients who underwent postoperative follow-up did not experience any further bleeding.Additionally,follow-up examination of the 8 cases who had declined surgery revealed that 3 of them experienced a recurrence of digestive tract bleeding.These findings indicate that laparoscopic diverticula resection in MD patients complicated by bleeding had a favorable prognosis.CONCLUSION Bleeding associated with MD was predominantly observed in male adolescents,particularly at a young age.DBE was a highly precise examination method in MD diagnosis.Laparoscopic diverticula resection effectively prevented MD bleeding and had a good prognosis. 展开更多
关键词 meckels diverticulum with bleeding Double-balloon colonoscopy 99mTc-pertechnetate scanning Capsule endoscopy Ectopic gastric mucosa
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多层螺旋CT对小肠Meckel’s憩室的诊断价值 被引量:6
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作者 王峰 赵宏亮 +5 位作者 李剑 鄂蓓 魏梦绮 宦怡 石明国 郑敏文 《医学影像学杂志》 2014年第1期76-79,共4页
目的探讨多层螺旋CT对小肠Meckel’s憩室的诊断价值。方法搜集经手术及病理证实的7例小肠Meckel’s憩室患者的临床与CT检查资料,回顾性分析检查方法对诊断结果的影响。结果 7例患者术前均做了多层螺旋CT增强扫描,其中3例做了肠道准备并... 目的探讨多层螺旋CT对小肠Meckel’s憩室的诊断价值。方法搜集经手术及病理证实的7例小肠Meckel’s憩室患者的临床与CT检查资料,回顾性分析检查方法对诊断结果的影响。结果 7例患者术前均做了多层螺旋CT增强扫描,其中3例做了肠道准备并行三维重建者,明确诊断为Meckel’s憩室2例,其中1例表现为回肠壁上的不规则盲管状含气突起,其壁较厚,增强扫描时显著强化,另1例表现为肠壁局限性向下突起的含液指状憩室,其内可见小结节状软组织影,增强扫描憩室壁及憩室内小结节均明显强化。3例未做肠道准备也未行三维重建者及1例未做肠道准备但行三维重建者均未发现憩室。结论多层螺旋CT增强扫描及三维重建图像后处理可全面、直观地显示Meckel’s憩室的位置、形态及其与邻近肠管的关系,对该病的诊断有很大的帮助,CT扫描前充分的肠道准备则是其必要条件。 展开更多
关键词 小肠 美克尔憩室 体层摄影术 X线计算机 图像处理
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Sonic hedgehog在小鼠胚胎下颌突Meckel's软骨发育过程中的表达 被引量:2
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作者 杜娟 范志朋 +4 位作者 马鑫 刘淑红 吴燕 范明 王松灵 《口腔生物医学》 2011年第1期3-7,共5页
目的:研究Sonic hedgehog(Shh)基因在小鼠胚胎颌面部Meckel's软骨发育不同阶段的表达,探讨Shh基因在下颌骨体发育骨化中的功能。方法:利用原位杂交和免疫组化技术检测Shh基因mRNA在小鼠胚胎11~14.5 dpc(days post coitum)阶段下颌... 目的:研究Sonic hedgehog(Shh)基因在小鼠胚胎颌面部Meckel's软骨发育不同阶段的表达,探讨Shh基因在下颌骨体发育骨化中的功能。方法:利用原位杂交和免疫组化技术检测Shh基因mRNA在小鼠胚胎11~14.5 dpc(days post coitum)阶段下颌突Meckel's软骨中的表达情况。结果:在颌面形成的早期阶段(11~12.5 dpc),Shh基因mRNA和蛋白在Meckel's软骨有表达且有增强趋势,但在颌面发育完成(14.5 dpc)后表达消失。结论:Shh基因可能参与下颌骨体早期发育。 展开更多
关键词 sonic HEDGEHOG 下颌骨 发育 meckel's软骨
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甲状旁腺激素相关蛋白对发育中的Meckel’s软骨作用的研究 被引量:2
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作者 赵青 奚春睿 李松 《昆明医学院学报》 2010年第9期27-31,共5页
目的观察SD大鼠下颌骨发育过程中甲状旁腺激素相关蛋白(PTHrP)在Meckel’s软骨上时空的变化,初步探讨PTHrP在Meckel’s软骨发育中的意义.方法用免疫组化染色法及原位杂交染色法检测E13-19dSD胎鼠的下颌骨发育过程中,PTHrP及PTHrPmRNA在M... 目的观察SD大鼠下颌骨发育过程中甲状旁腺激素相关蛋白(PTHrP)在Meckel’s软骨上时空的变化,初步探讨PTHrP在Meckel’s软骨发育中的意义.方法用免疫组化染色法及原位杂交染色法检测E13-19dSD胎鼠的下颌骨发育过程中,PTHrP及PTHrPmRNA在Meckel’s软骨上的表达.结果 E13-15d在Meckel’s软骨前段PTHrP蛋白强阳性表达,在细胞核、胞浆均表达,在肥大软骨细胞核上表达更明显,而且PTHrPmRNA强阳性表达的位置与PTHrP蛋白一致.E17-19d Meckel’s软骨前段骨化,E17d在临近成骨处的Meckel’s软骨软骨细胞PTHrP蛋白弱阳性表达,且位于肥大软骨细胞核内,PTHrPmRNA阴性表达.E19dPTHrP临近成骨处蛋白染色阴性表达,PTHrPmRNA阴性表达;在前段远离骨化处PTHrPmRNA,PTHrP蛋白强阳性表达,细胞核上表达明显.结论 PTHrP在Meckel’s软骨前段软骨细胞中的表达存在时空特异变化,提示PTHrP蛋白可能由SD大鼠Meckel's软骨软骨细胞合成,并作为一种自分泌因子调节Meckel’s软骨细胞的增殖和分化. 展开更多
关键词 meckels软骨 下颌骨 发育 甲状旁腺激素相关蛋白
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^(99m)TcO_4^-腹部断层显像诊断小儿Meckel’s憩室并出血的价值 被引量:1
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作者 高明太 刘纯 +1 位作者 陈明 李乐 《兰州大学学报(医学版)》 CAS 2005年第2期85-85,109,共2页
关键词 ^99mTcO4^-腹部断层显像 小儿 meckels憩室 腹部出血 MD 胃粘膜
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西咪替丁介入放射性核素显像诊断儿童Meckel’s憩室一例 被引量:1
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作者 陈明 刘纯 +2 位作者 何津祥 高明太 杨鹏 《兰州大学学报(医学版)》 CAS 2001年第3期32-32,共1页
关键词 介入放射性核素 meckels憩室 西咪替丁 显像诊断 麦克尔憩室 胃粘膜 断层显像 西米替丁 儿童 平面显像
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经乳突入路Meckel’s囊及其毗邻结构的应用解剖 被引量:1
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作者 王君玉 党瑞山 +3 位作者 胡国汉 廖建春 刘环海 卢亦成 《解剖与临床》 2008年第3期154-156,共3页
目的:为临床手术中Meckel’s囊的切开提供解剖学资料。方法:经10%甲醛固定成人尸头标本15具30侧,模拟乙状窦前(迷路后)入路及乙状窦后入路,内窥镜下观察Meckel’s囊口及毗邻结构。而后开颅取脑,三叉神经自Meckel’s囊处切断。解剖Meckel... 目的:为临床手术中Meckel’s囊的切开提供解剖学资料。方法:经10%甲醛固定成人尸头标本15具30侧,模拟乙状窦前(迷路后)入路及乙状窦后入路,内窥镜下观察Meckel’s囊口及毗邻结构。而后开颅取脑,三叉神经自Meckel’s囊处切断。解剖Meckel’s囊,观察其与周围结构的关系,测量Meckel’s囊口的前后径、宽度,Meckel’s囊的组成,与Dorello管外口、岩静脉、内耳道的距离。结果:Meckel’s囊口的最长径为(9.53±1.66)mm、最宽径为(2.99±0.43)mm,Meckel’s囊口上端到Dorello管口的距离为(6.99±1.30)mm。Meckel’s囊口到内耳道、岩静脉、岩上窦-乙状窦交点的最近距离分别为(9.80±1.61)mm、(9.40±1.65)mm、(38.41±2.49)mm。结论:部分Meckel’s外侧壁两层硬膜之间夹有独立的骨片,增加了Meckel’s囊区域操作的难度,解剖中测量的数据为Meckel’s囊附近的手术提供了参考。 展开更多
关键词 meckels 三叉神经 内耳道 乙状窦前入路 解剖
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动态显像诊断儿童Meckel’s憩室
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作者 张青 叶斌华 《实用临床医学(江西)》 CAS 2002年第A01期86-86,共1页
关键词 meckels憩室 动态显像诊断 儿童
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术中球囊扩张容积-Meckel腔体积比值与PMC治疗原发性三叉神经痛疗效的关系 被引量:2
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作者 莫凯 郭贤放 +1 位作者 姚鑫 廖声潮 《中国临床神经外科杂志》 2023年第5期311-313,317,共4页
目的探讨术中球囊扩张容积-Meckel腔体积比值与经皮穿刺微球囊压迫术(PMC)治疗原发性三叉神经痛(PTN)疗效的关系。方法回顾性分析2019年3月至2021年8月PMC治疗的41例PTN的临床资料。术前MRI三维重建扫描测定Meckel腔体积,计算术中球囊... 目的探讨术中球囊扩张容积-Meckel腔体积比值与经皮穿刺微球囊压迫术(PMC)治疗原发性三叉神经痛(PTN)疗效的关系。方法回顾性分析2019年3月至2021年8月PMC治疗的41例PTN的临床资料。术前MRI三维重建扫描测定Meckel腔体积,计算术中球囊扩张容积与Meckel腔体积的比值。术后随访6~18个月,末次随访参考巴罗德神经病学研究所疼痛预后分级(BNI)评估疗效,其中Ⅰ~Ⅱ级为有效,Ⅲ~Ⅴ级为无效。结果末次随访,有效31例,无效10例。有效组和无效组Meckel腔体积(0.43±0.20 cm^(3) vs.0.51±0.22 cm^(3))、术中球囊扩张容积(0.61±0.23 ml vs.0.49±0.20 ml)均无统计学差异(P>0.05),而有效组术中球囊扩张容积与Meckel腔体积的比值(1.46±0.26)明显大于无效组(0.98±0.12;P<0.05)。结论通过术前测量Meckel腔体积,以球囊扩张容积-Meckel腔体积比值的有效区间为参考依据,术中对球囊扩张容积进行把控,可提高PMC治疗PTN的疗效。 展开更多
关键词 原发性三叉神经痛 经皮穿刺微球囊压迫术 术中球囊扩张容积 meckel腔体积 疗效
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小儿Meckel's憩室内翻套入回肠并发肠套叠及穿孔1例
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作者 谭悦菊 孙光喜 《中国社区医师》 2016年第20期105-105,107,共2页
小儿Meckel's憩室并发肠套叠及穿孔是儿科急腹症之一,一经确诊应及早外科手术。本文介绍小儿Meckel's憩室内翻套入回肠并发肠套叠及穿孔1例。
关键词 meckel's憩室 小儿 手术
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小儿Meckel’s憩室24例临床分析
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作者 蒋志凌 《四川省卫生管理干部学院学报》 2005年第4期297-297,共1页
目的:探讨小儿Meckel’s憩室的临床表现、诊断方法及与组织形态的关系。方法:回顾性分析本院近10年经手术病理证实为Meckel’s憩室的小儿患者24例。结果:Meckel’s憩室并发下消化道出血15例、肠梗阻4例,下消化道出血患儿中14例行99mTcO-... 目的:探讨小儿Meckel’s憩室的临床表现、诊断方法及与组织形态的关系。方法:回顾性分析本院近10年经手术病理证实为Meckel’s憩室的小儿患者24例。结果:Meckel’s憩室并发下消化道出血15例、肠梗阻4例,下消化道出血患儿中14例行99mTcO-4腹部显像,与病理符合率为57%。结论:下消化道出血是小儿Meckel’s憩室的常见并发症,核素显像是术前诊断的主要方法,活动期出血、血管畸形可导致假阳性率增加。 展开更多
关键词 meckels憩室 小儿 并发症 核素显像
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Lipoma within inverted Meckel’s diverticulum as a cause of recurrent partial intestinal obstruction and hemorrhage: A case report and review of literature 被引量:12
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作者 Güldeniz Karadeniz Cakmak Ali Ugur Emre +6 位作者 Oge Tascilar Sibel Bekta■ Bulent Hamdi Uan Oktay Irkorucu Kemal Karakaya Yucel Ustundag Mustafa Comert 《World Journal of Gastroenterology》 SCIE CAS CSCD 2007年第7期1141-1143,共3页
Lipoma within an inverted Meckel's diverticulum presen- ting with hemorrhage and partial intestinal obstruction is an exceptional clinical entity. We report a case of 47-year-old male with a history of recurrent e... Lipoma within an inverted Meckel's diverticulum presen- ting with hemorrhage and partial intestinal obstruction is an exceptional clinical entity. We report a case of 47-year-old male with a history of recurrent episodes of partial intestinal obstruction and melena due to a subserosal lipoma located in the base of an inverted Meckel's diverticulum. According to our knowledge, this is the first case of a lipoma within a Meckel's diverticulum giving rise to this clinical scenario without the existence of heterotrophic gastric or pancreatic tissues. 展开更多
关键词 meckel's diverticulum LIPOMA INVERsION Intestinal obstruction HEMORRHAGE
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手术治疗Meckel’s憩室20例 被引量:1
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作者 张继光 林宏福 《临床外科杂志》 2003年第S1期34-35,共2页
目的 提高对Meckel’s憩室的诊治水平。方法 回顾性总结经手术及病理证实的Meckel’s憩室 2 0例 ,14例因并发症手术 ,6例在其他手术中发现。结果  15例行单纯楔形切除 ,5例行肠切除吻合术。术后无并发症发生。结论 Meckel’s憩室属... 目的 提高对Meckel’s憩室的诊治水平。方法 回顾性总结经手术及病理证实的Meckel’s憩室 2 0例 ,14例因并发症手术 ,6例在其他手术中发现。结果  15例行单纯楔形切除 ,5例行肠切除吻合术。术后无并发症发生。结论 Meckel’s憩室属先天性畸形 ,术前不易诊断。其并发症发生率约为 4% ,依次为 :憩室炎 (常合并出血 ) ,肠套叠 ,嵌顿疝 ,肿瘤等 ,手术治疗效果好。 展开更多
关键词 meckels憩室 并发症 手术治疗
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Inverted Meckel's diverticulum as a cause of occult lower gastrointestinal hemorrhage 被引量:9
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作者 Omar M Rashid Joseph K Ku +2 位作者 Masayuki Nagahashi Akimitsu Yamada Kazuaki Takabe 《World Journal of Gastroenterology》 SCIE CAS CSCD 2012年第42期6155-6159,共5页
Meckel's diverticulum is a common asymptomatic congenital gastrointestinal anomaly,but rarely it can present with hemorrhage.Over the last few years inverted Meckel's diverticulum has been reported in the lite... Meckel's diverticulum is a common asymptomatic congenital gastrointestinal anomaly,but rarely it can present with hemorrhage.Over the last few years inverted Meckel's diverticulum has been reported in the literature with increasing frequency as an occult source of lower gastrointestinal hemorrhage.Here,we report a case of a 54-year-old male,who was referred for surgical evaluation with persistent anemia and occult blood per rectum after a work up which failed to localize the source over 12 mo,including upper and capsule endoscopy,colonoscopy,enteroclysis,Meckel scan,and tagged nuclear red blood cell scan.An abdominal computed tomography scan showed a possible mid-ileal intussusception and intraluminal mass.During the abdominal exploration,inverted Meckel's diverticulum was diagnosed and resected.We review the literature,discuss the forms in which the disease presents,the diagnostic modalities utilized,pathological findings,and treatment.Although less than 40 cases have been reported in the English literature from 1978 to 2005,19 cases have been reported in the last 6 years alone(2006-2012) due to improved diagnostic modalities.Successful diagnosis and treatment of this disease requires a high index of clinical suspicion,which is becoming increasingly relevant to general gastroenterologists. 展开更多
关键词 Inverted meckel's diverticulum Gastrointestinal hemorrhage Lower gastrointestinal bleeding Intussusceptions
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Intestinal obstruction caused by torsed gangrenous Meckel's diverticulum encircling terminal ileum 被引量:7
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作者 Carmine Cartanese Tommaso Petitti +4 位作者 Ernesto Marinelli Antonio Pignatelli Davide Martignetti Matteo Zuccarino Lucio Ferrozzi 《World Journal of Gastrointestinal Surgery》 SCIE CAS 2011年第7期106-109,共4页
Meckel's diverticulum(MD)is considered the most prevalent congenital anomaly of the gastrointestinal tract. It may result in a number of complications including hemorrhage,obstruction,and inflammation.Obstruction ... Meckel's diverticulum(MD)is considered the most prevalent congenital anomaly of the gastrointestinal tract. It may result in a number of complications including hemorrhage,obstruction,and inflammation.Obstruction of various types is the most common presenting symptom in the adult population.Loop formations with the end of an MD and adjacent mesentery constricting the distal ileum is an uncommon cause of obstruction. Axial torsion and gangrene of MD is the rarest of the complications.The correct diagnosis of complicated MD before surgery is often difficult because this condition may mimic other acute abdominal pathologies.Delay in the diagnosis of a complicated MD can lead to signifi- cant morbidity and mortality.Here we describe the case of a patient with a very rare form of acute small bowel obstruction secondary to giant torsed gangrenous MD encircling the terminal ileum.To our knowledge, this co-occurrence of axial torsion and a loop-forming mechanism of obstruction has been reported only once in English medical literature. 展开更多
关键词 meckels DIVERTICULUM Axial TORsION GANGRENE Intestinal OBsTRUCTION Mesodiverticular band
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Inverted Meckel’s diverticulum manifested as adult intussusception: Age does not matter 被引量:7
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作者 Eleni Sioka Gregory Christodoulidis +1 位作者 Grigorios Garoufalis Dimitris Zacharoulis 《World Journal of Gastrointestinal Surgery》 SCIE CAS 2011年第8期123-127,共5页
Adult intussusception due to Meckel’s diverticulum (MD) is an uncommon cause of intestinal obstruction. However, the surgeon should still be suspicious of this condition since the non specific symptoms and the rarity... Adult intussusception due to Meckel’s diverticulum (MD) is an uncommon cause of intestinal obstruction. However, the surgeon should still be suspicious of this condition since the non specific symptoms and the rarity of it make a preoperative diagnosis uncertain. Considering the secondary nature of adult intussusception and the necessity of early surgical intervention to avoid morbidity and mortality, we report two cases of intussusception due to MD in adults. A diverticulectomy using a TA stapler was performed in the first patient. In the second patient extensive fibrosis of the adjacent mesentery and thickening of jejunal mucosa were observed, so a segmental resection of the small bowel or affected ileal part and a hand-sewn anastomosis was performed. The postoperative period along with the long term follow-up was uneventful for both patients. The decision between diverticulectomy vs bowel resection can be based on the intussuscepted bowel condition. Early surgical intervention may ensure a favorable outcome. 展开更多
关键词 INVERTED meckels DIVERTICULUM Adult INTUssUsCEPTION Emergency surgery Intestinal OBsTRUCTION COMPUTED tomography DIVERTICULECTOMY
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CO_(2)/CO干扰下基于腔衰荡吸收光谱的痕量H_(2)S浓度测量 被引量:3
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作者 熊枫 彭志敏 +3 位作者 王振 丁艳军 吕俊复 杜艳君 《物理学报》 SCIE EI CAS CSCD 北大核心 2023年第4期35-43,共9页
H_(2)S作为一种有毒且腐蚀性较强的气体污染物,实现其浓度的准确测量意义重大.实际工业过程中,H_(2)S测量常受其他排放产物的干扰,本文基于腔衰荡吸收光谱技术(CRDS)通过扫描6336—6339 cm^(-1)范围内的吸收光谱,实现了H_(2)S/CO_(2)/C... H_(2)S作为一种有毒且腐蚀性较强的气体污染物,实现其浓度的准确测量意义重大.实际工业过程中,H_(2)S测量常受其他排放产物的干扰,本文基于腔衰荡吸收光谱技术(CRDS)通过扫描6336—6339 cm^(-1)范围内的吸收光谱,实现了H_(2)S/CO_(2)/CO三组分物质浓度的同步测量,为实际工业过程中物质干扰下的H_(2)S浓度测量提供新思路.首先,对不同采样长度下提取衰荡时间的准确性进行分析,发现衰荡信号的采样长度约为衰荡时间的8倍时,衰荡时间提取效果最好;通过不同压力对比实验确定最佳实验压力工况为50 kPa,并将最佳采样长度与压力工况应用于H_(2)S浓度测量.随后,改变H_(2)S浓度对CO_(2)/CO干扰下系统对痕量H_(2)S浓度的测量效果进行检验,并对不同稀释比例下浓度测量结果的线性度进行分析.最后,对本文CRDS系统的检测限进行分析,通过对4组低浓度H_(2)S光谱的信噪比进行分析,得到H_(2)S的检出限为6.9 ppb (1 ppb=10^(-9));通过对系统长期测量结果进行Allan方差分析,得到系统对H_(2)S物质浓度的检测下限约在2 ppb左右. 展开更多
关键词 腔衰荡吸收光谱 H_(2)s浓度 多组分测量
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Diffraction of plane SV waves by a cavity in poroelastic half-space 被引量:15
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作者 Liang Jianwen and Liu Zhongxian Department of Civil Engineering, Tianjin University, Tianjin 300072, China Professor PhD Candidate 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2009年第1期29-46,共18页
This paper presents an indirect boundary integration equation method for diffraction of plane SV waves by a 2-D cavity in a poroelastic half-space.The Green's functions of compressive and shear wave sources are deriv... This paper presents an indirect boundary integration equation method for diffraction of plane SV waves by a 2-D cavity in a poroelastic half-space.The Green's functions of compressive and shear wave sources are derived based on Biot's theory. The scattered waves are constructed using fictitious wave sources close to the boundary of the cavity, and their magnitudes are determined by the boundary conditions. Verification of the accuracy is performed by: (1) checking the satisfaction extent of the boundary conditions, (2) comparing the degenerated solutions of a single-phased case with well- known solutions, and (3) examining the numerical stability of the solutions. The nature of diffraction of plane SV waves around a cavity in a poroelastic half-space is investigated by numerical examples. 展开更多
关键词 poroelastic half-space cavity DIFFRACTION plane sV waves compressive wave source shear wave source Green's function pore pressure
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Meckel's diverticulum bleeding diagnosed with magnetic resonance enterography:A case report 被引量:3
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作者 Fu-Run Zhou Liu-Ye Huang Hai-Zhu Xie 《World Journal of Gastroenterology》 SCIE CAS 2013年第17期2727-2730,共4页
Although the introduction of double-balloon enteroscopy has greatly improved the diagnostic rate, definite diagnosis of Meckel's diverticulum far from the ileocecal valve is still impossible in most cases. We expl... Although the introduction of double-balloon enteroscopy has greatly improved the diagnostic rate, definite diagnosis of Meckel's diverticulum far from the ileocecal valve is still impossible in most cases. We explored the role of magnetic resonance (MR) enterography in detecting bleeding from Meckel's diverticulum that can not be confirmed via double-balloon enteroscopy. This study describes a case of male patient with bleeding from Meckel's diverticulum diagnosed with MR enterography of the small intestine. No bleeding lesion was found via colonoscopy, anal enteroscopy, or oral colonoscopy. MR enterography of the small intestine revealed an occupying lesion of 3.0 cm in the lower segment of the ileum. The patient was transferred to the Department of Abdominal Surgery of our hospital for surgical treatment. During surgery, a mass of 3 cm × 2 cm was found 150 cm from the ileocecal valve, in conjunction with congestion and edema of the corresponding mesangium. Intraoperative diagnosis was small bowel diverticulum with bleeding. The patient underwent partial resection of the small intestine. Postopera-tive pathology showed Meckel's diverticulum containing pancreatic tissues. He was cured and discharged 7 d after operation. We conclude that MR enterography of the small intestine has greatly improved the diagnosis rate of Meckel's diverticulum, particularly in those patients with the disease which can not be confirmed via double-balloon enteroscopy. 展开更多
关键词 meckels DIVERTICULUM Double-balloon ENTEROsCOPY Magnetic REsONANCE ENTEROGRAPHY
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