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Eduardo Rodrigues‐Pinto Joel Ferreira‐Silva Guilherme Macedo Douglas K. Rex 《Digestive endoscopy》2019,31(5):583-587
Cecal intubation is a critical aspect of effective, complete colonoscopy. Difficult colonoscopy is most often considered as one in which it is challenging or impossible to reach the cecum. It may be a common occurrence due to patient and/or endoscopist factors. Incomplete colonoscopies should be avoided, since patients in this context present an important prevalence of lesions that escape examination. The approach to successful cecal intubation should depend on characterization of the problem as redundant colon or difficult sigmoid colon. Most patients with a prior incomplete colonoscopy can be colonoscoped successfully, if careful attention is paid to technique, using a variety of scopes, colonoscopy methods and additional equipment. Sufficient time should be allotted to make the attempt. 相似文献
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WEIGUANG ZENG PIERRE-OLIVIER REGAMEY KEITH ROSE YUZHOU WANG ERNST BAYER 《Chemical biology & drug design》1997,49(3):273-279
The use of N, O-bisFmoc-N-(2-hydroxy-4-methoxybenzyl) amino acid derivatives in the synthesis of peptides with difficult sequences has already been described. With these amino acid derivatives the reversible protecting group 2-hydroxy-4-methoxybenzyl (Hmb) for the backbone amide bonds of peptide chains is introduced, and thus the aggregation due to hydrogen-bond interchain association is inhibited. This paper describes the synthesis and use of Fmoc-N-(2-hydroxy-4-methoxybenzyl)amino acid derivatives as an alternative means of introducing Hmb backbone protection. These new monoFmoc derivatives were obtained in higher yield than the bisFmoc derivatives. Coupling yields to the amino peptide resin were the same as those obtained with bisFmoc derivatives, under the TBTU/HOBt/DIEA conditions. We also compared different syntheses of a difficult peptide with the Fmoc approach [triple coupling, capping, use of chaotropic agents, backbone protection using monoFmoc (Hmb)Ala] and with optimized Boc chemistry. Both the backbone protection and optimized Boc chemistry approaches gave the desired product in excellent yield and purity. © Munksgaard 1997. 相似文献
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Atsushi Ota Nobuyasu Kano Hiroshi Kusanagi Shigetoshi Yamada Arty Garg 《Journal of hepato-biliary-pancreatic sciences》2003,10(2):172-175
Our basic techniques for the management of difficult cases of laparoscopic cholecystectomy (LC) are presented in this article. If access to Calot's triangle cannot be gained safely, dissection should be started at the fundus or body of the gallbladder (GB), rather than the neck (fundus-first method). In cases with a short and wide cystic duct, a transfixing suture should be applied for ligation instead of clipping. EndoGIA is useful for ligating and transecting this case to avoid a subsequent stricture caused by normal method of ligation. Intraoperative cholangiography should be performed near the neck of the GB in cases in which orientation is lost during dissection. More dissection should be performed in the direction of the junction of the bile ducts after orientation is regained. In cases with GB filled with stones accompanied by severe fibrosis, part of the GB is incised to remove the stones and expose the lumen of the GB. Confluence stones can be removed by placing an incision on the GB side of the junction of the duct. The incised part is closed with suture. A cystic tube (C-tube) is placed in the common bile duct through the cystic duct for decompression. In more difficult cases in which dissection cannot be started safely at any location, the body and the fundus of the GB are excised, and a drain is placed at the neck of the GB. Dissection can be carried out from the main surgeon's or the assistant's side depending on the situation, and cooperation between the two surgeons is mandatory to achieve safe LC in difficult cases. When performing the LC, one must have a low threshold for converting to open surgery if injuries cannot be managed safely. 相似文献
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目的:探讨心理干预对3-7岁麻烦型气质儿童的餐桌行为的作用。方法:用CTPS(China Preschool-children Temperament Scale)问卷方式对410名3-7岁儿童的气质类型进行综合评定划分出5个气质类型;对其中50名麻烦型气质儿童的餐桌行为问题进行了3个月的心理干预治疗。并对其餐桌行为做干预前后的偏挑食行为,改善进餐情绪,提高进餐速度有效。结论:心理干预可以纠正儿童的餐桌行为。 相似文献
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困难气管内插管的预测和处理 总被引:6,自引:0,他引:6
斯小龙 《杭州医学高等专科学校学报》2001,22(3):145-146,156
目的 探讨对困难气管内插管的预测及处理方法。方法 随机选取各类需行气管内插管麻醉下择期手术患者50例,术前测量IG、Slux,TM,HENE,HFNF、气道分类及声门分级等各项指标,并分析它们在气管插管难度之间的关系。结果 50例患者中,气道分类Ⅳ类者7例,声门分级Ⅲ级者17例,Ⅳ级者1例。17例声门Ⅲ级者以EtCO2引导下口腔盲插法插管成功,1例声门Ⅳ级者以气囊充气鼻腔盲控气管内插管法插管成功。结论 术前评价气管插管难易程度应综合考察各项测量指标,这些指标中又以声门分级最为可靠。 相似文献
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头位难产的分娩方式和新生儿窒息风险关系 总被引:1,自引:1,他引:0
李文华 《河南大学学报(医学版)》2001,20(4):24-25
目的 :探讨头位难产分娩方式与新生儿窒息风险关系。方法 :应用头位分娩评分法对 135例足月单胎头位难产初产妇进行评分 ,按评分分组处理。结果 : ≤ 8分 ,剖宫产率 10 0 % ,新生儿窒息率 16 7%。 9分 ,10分 ,11分3组分娩方式具有显著性差异 ,P <0 0 5。 3组阴道分娩的新生儿窒息率 ,差异无显著性 ,P >0 0 5。结论 :评分≤ 9分者应放宽剖宫产指标 ,评分 10分者应作短期试产。评分 >10分者大胆试产 ,阴道分娩不因评分低而增加新儿窒息率。 相似文献
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关思友先生治疗疑难病时,在辨证论治的基础上,借鉴前医经验,注重逆向思维,取得良好的临床疗效。临证时,不囿表面所见,把细究病因放在重要地位,并提倡“治病不可因循守旧,固守古训,要圆机活法,因人、因地、因时治宜,有是证用是药。” 相似文献