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Regan E. Giesinger Adrianne R. Bischoff Patrick J. McNamara 《Congenital heart disease》2019,14(2):311-316
Ligation of a hemodynamically significant ductus arteriosus results in significant changes in loading conditions which have predictable consequences. Postligation cardiac syndrome, defined as hypotension requiring inotropic support and failure of oxygenation and ventilation, may occur 6‐12 hours following ligation due to left ventricular systolic and diastolic failure, respectively. Afterload is the primary driver of this decompensation. In this review, we describe the pathophysiological changes in loading conditions associated with postligation cardiac syndrome and other contributors to cardiovascular dysfunction following ductal ligation. We present strategies for perioperative optimization and a physiology‐based algorithm for postoperative management guided by targeted neonatal echocardiography. The use of these strategies to reduce the frequency of postligation deterioration may be an avenue to improve outcomes for neonates in this vulnerable patient population. 相似文献
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《Journal of pediatric surgery》2023,58(6):1090-1094
BackgroundThe purpose of this study was to assess diagnostic accuracy and neonatal outcomes in fetuses with a suspected proximal gastrointestinal obstruction (GIO).MethodsAfter IRB approval, a retrospective chart review was conducted on prenatally suspected and/or postnatally confirmed cases of proximal GIO at a tertiary care facility (2012–2022). Maternal-fetal records were queried for presence of a double bubble ± polyhydramnios, and neonatal outcomes were assessed to calculate the diagnostic accuracy of fetal sonography.ResultsAmong 56 confirmed cases, the median birthweight and gestational age at birth were 2550 g [interquartile range (IQR) 2028–3012] and 37 weeks (IQR 34–38), respectively. There was one (2%) false-positive and three (6%) false-negatives by ultrasound. Double bubble had a sensitivity, specificity, positive predictive value, and negative predictive value for proximal GIO of 85%, 98%, 98%, and 83%, respectively. Pathologies included 49 (88%) with duodenal obstruction/annular pancreas, three (5%) with malrotation, and three (5%) with jejunal atresia. The median postoperative length of stay was 27 days (IQR 19–42). Cardiac anomalies were associated with significantly higher complications (45% vs 17%, p = 0.030).ConclusionsIn this contemporary series, fetal sonography has high diagnostic accuracy for detecting proximal gastrointestinal obstruction. These data are informative for pediatric surgeons in prenatal counseling and preoperative discussions with families.Level of EvidenceDiagnostic Study, Level III. 相似文献
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RYOSAKU TOMIYAMA FUKUNORI KINJO AKIRA HOKAMA TSUYOSHI MIYAGI HIROKI NAKASONE NAGISA KINJO HIROSHI SAKUGAWA ATSUSHI SAITO 《Digestive endoscopy》2003,15(2):125-127
We report a case of a patient in whom endoscopic band ligation was achieved for postpolypectomy gastric bleeding. A 76‐year‐old man visited our hospital because of anemia. Endoscopy revealed a gastric polyp, approximately 12 mm in diameter, on the lesser curvature in the distal gastric body. The polyp was considered to be the source of chronic anemia and was therefore removed by using standard careful snare‐cautery polypectomy technique. Four days later, follow‐up endoscopy was performed to evaluate the postpolypectomy site, and an active bleeding postpolypectomy ulcer was identified. Initial attempts to achieve hemostasis with ethanol injection were unsuccessful. Immediate hemostasis was obtained with a subsequent endoscopic band ligation device. There has been no recurrent bleeding. Endoscopic band ligation might be a good treatment modality for the treatment of a postpolypectomy gastric bleeding lesion. 相似文献
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Marta Méndez-López Magdalena Méndez Fernando Sánchez-Patán Isabel Casado Maria-Angeles Aller Laudino López Maria-Teresa Corcuera Maria-Jose Alonso Maria-Paz Nava Jaime Arias Jorge-Luis Arias 《Journal of gastrointestinal surgery》2007,11(2):187-194
To obtain a new model of chronic portal hypertension in the rat, two classical methods to produce portal hypertension, partial portal vein ligation and the oral administration of thioacetamide (TAA), have been combined. Male Wistar rats were divided into four groups: 1 (control; n?=?10), 2 [triple partial portal vein ligation (TPVL); n?=?9], 3 (TAA; n?=?11), and 4 (TPVL plus TAA; n?=?9). After 3 months, portal pressure, types of portosystemic collateral circulation, laboratory hepatic function tests (aspartate aminotransferase, alanine aminotransferase, bilirubin, alkaline phosphatase, and gamma-glutamyl transpeptidase) and liver histology were studied. The animals belonging to group 2 (TPVL) developed extrahepatic portosystemic collateral circulation, associated with mesenteric venous vasculopathy without hepatic destructurization or portal hypertension. Animals from group 3 (TAA) developed cirrhosis and portal hypertension but not extrahepatic portosystemic collateral circulation, or mesenteric venous vasculopathy. Finally, the animals from group 4 (TPVL?+?TAA) developed cirrhosis, portal hypertension, portosystemic collateral circulation, and mesenteric venous vasculopathy. The association of TPVL and TAA can be used to obtain a model of chronic portal hypertension in the rat that includes all the alterations that patients with hepatic cirrhosis usually have. This could, therefore, prove to be a useful tool to study the pathophysiological mechanisms involved in these alterations. 相似文献
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微小切口双重荷包缝合法矫正重度乳头内陷 总被引:7,自引:0,他引:7
目的 介绍一种疗效确切,创伤小,矫正重度乳头内陷的新术式.方法 设计切口位于乳晕第四象限,方向斜向外下方,呈放射状切口,长约1.5 cm,松解乳头基底部,切断牵拉的纤维条索,上提乳头,在距乳头0.8cm和1.5cm处,双重荷包缝合固定.结果 12例乳头内陷患者术后随访1个月至4年,均获得满意疗效.乳头横径、纵径、高度及外观明显改善.结论 该术式矫正乳头内陷具有切口小、创伤轻微、操作简单易行、效果确切、不易复发和并发症少等优点. 相似文献
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Abstract: Native chemical ligation has proven to be a powerful method for the synthesis of small proteins and the semisynthesis of larger ones. The essential synthetic intermediates, which are C‐terminal peptide thioesters, cannot survive the repetitive piperidine deprotection steps of Nα‐9‐fluorenylmethoxycarbonyl (Fmoc) chemistry. Therefore, peptide scientists who prefer to not use Nα‐t‐butyloxycarbonyl (Boc) chemistry need to adopt more esoteric strategies and tactics in order to integrate ligation approaches with Fmoc chemistry. In the present work, side‐chain and backbone anchoring strategies have been used to prepare the required suitably (partially) protected and/or activated peptide intermediates spanning the length of bovine pancreatic trypsin inhibitor (BPTI). Three separate strategies for managing the critical N‐terminal cysteine residue have been developed: (i) incorporation of Nα‐9‐fluorenylmethoxycarbonyl‐S‐(N‐methyl‐N‐phenylcarbamoyl)sulfenylcysteine [Fmoc‐Cys(Snm)‐OH], allowing creation of an otherwise fully protected resin‐bound intermediate with N‐terminal free Cys; (ii) incorporation of Nα‐9‐fluorenylmethoxycarbonyl‐S‐triphenylmethylcysteine [Fmoc‐Cys(Trt)‐OH], generating a stable Fmoc‐Cys(H)‐peptide upon acidolytic cleavage; and (iii) incorporation of Nα‐t‐butyloxycarbonyl‐S‐fluorenylmethylcysteine [Boc‐Cys(Fm)‐OH], generating a stable H‐Cys(Fm)‐peptide upon cleavage. In separate stages of these strategies, thioesters are established at the C‐termini by selective deprotection and coupling steps carried out while peptides remain bound to the supports. Pilot native chemical ligations were pursued directly on‐resin, as well as in solution after cleavage/purification. 相似文献
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门静脉主干缩窄法制备SD大鼠门静脉高压症模型时最佳口径的探讨 总被引:1,自引:0,他引:1
目的 探讨缩窄门静脉主干法制备SD大鼠门静脉高压症模型时的最佳缩窄口径.方法 SD大鼠70只,随机分为正常组和6个实验组,每组各10只.正常组行假手术.各实验组分别按照5、6、7、8、9、12号针头的缩窄口径行门静脉主干缩窄术.观察各组大鼠术后累积死亡率,术后状态,术前、术后即刻及术后2周时的门静脉压力,术后2周时的食管组织学变化和脾指数.结果 5、6、7、8、9、12号针头缩窄组术后3 d时大鼠的累积死亡率分别为100%、80%、70%、20%、10%、0%,与缩窄程度正相关.8、9、12号组的大鼠存活状态明显好于5、6、7号组.5、6、7、8、9、12号组术后即刻门静脉压力分别为:(5.836±0.275)、(4.557±0.419)、(3.856±0.576)、(3.343±0.433)、(2.708±0.309)、(1.957±0.358)kPa,7、8、9、12号组术后2周时门静脉压力分别为:(2.163±0.424)、(1.956±0.172)、(1.841±0.202)、(1.232±0.154)kPa,均较正常(0.881±0.165)kPa显著升高(P<0.05).术后2周,7、8、9、12号组大鼠食管下段黏膜下层平均血管数目分别为:(3.94±0.83)、(3.58±0.63)、(3.14±0.64)、(2.02±0.62)个,与正常组(1.65±0.62)个比较,除12号组外均有增多(P<0.01);固有层平均血管数目分别为:(2.24±0.64)、(2.05±0.29)、(1.52±0.28)、(0.93±0.19)个,与正常组(0.82±0.18)比较,除第12组外均增多(P<0.01);黏膜下层血管口径分别为:(4.52±1.51)、(4.05±1.23)、(3.75±1.11)、(2.03±0.86)μm,除第12组外均增大(P<0.01);脾指数分别为:(4.21±0.93)、(4.06±0.68)、(3.84 4±0.71)、(3.31±0.69)除12号组外也较正常增加(P<0.01).结论 缩窄门静脉主干可成功制成大鼠门静脉高压症模型;其最佳缩窄口径应该是:大鼠体重200 g左右时用8号针头(直径0.8mm),大鼠体重300 g左右时用9号针头(直径0.9 mm). 相似文献