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921.
Background and objective:   The treatment choice for post-intubation tracheal stenosis (PITS) in patients for whom surgery is not initially feasible is bronchoscopic silicone stenting. A new silicone stent, called the Natural stent (N stent), was investigated for its clinical efficacy and safety in patients with PITS.
Methods:   A retrospective review was conducted of 32 patients with PITS who underwent N stenting between November 2001 and December 2006 and were followed for at least 12 months.
Results:   Airway dilatation with combined modalities such as Nd : YAG laser, ballooning or bougienage was followed by N stent insertion. After intervention, all patients had symptomatic and spirometric improvement without immediate complications. Removal of the stent without re-stenosis was successful in 38% of the patients at a median time of 7 months after insertion. The stent could not be removed or needed reinsertion in 31% of patients, and 16% of patients underwent surgery after initial stabilization by stenting. Late complications were stent migration (34%), mucostasis (31%), granulation tissue formation (38%) and re-stenosis (40%). All patients tolerated the management of complications during a median follow up of 22 months.
Conclusions:   Bronchoscopic N stenting is an effective treatment for patients with PITS in whom surgery is not feasible on initial presentation. Further stent development is necessary to reduce the late complication rate.  相似文献   
922.
Abstract: We present two cases wherein vitiligo developed after the onset of halo formation involving congenital melanocytic nevi to emphasize the possibility of this finding as a potential albeit unusual presentation of vitiligo.  相似文献   
923.
Here, we present a case of immature teratoma of prostatic origin, which included an angiosarcoma component. This mass proved unresponsive against preoperative chemotherapy for immature teratoma. Angiosarcoma, although quite rare, should be included in the differential diagnosis as a component of prostatic teratoma, especially in cases in which the tumor proves unresponsive to well-known chemotherapeutic protocols. This is, to our knowledge, the first reported case of primary prostatic immature teratoma containing an angiosarcoma component.  相似文献   
924.
We report a unique case of eosinophilic cystitis causing intraperitoneal bladder perforation in a child diagnosed by chance with no signs or history of trauma. To our knowledge, this is the first case of eosinophilic cystitis complicated by bladder rupture in children. The patient was successfully treated with primary repair. For children with non-traumatic bladder perforation, eosinophilic cystitis must be considered in the differential diagnosis.  相似文献   
925.
926.
目的 用细菌/杆状病毒(Bac to Bac)表达系统在昆虫细胞Sf9中表达HIV-2外膜糖蛋白gp105跨膜糖蛋白gp36,为研制艾滋病疫苗和诊断试剂奠定基础。方法 分别将HIV-2外膜蛋白gp105和跨膜蛋白gp36全基因序列克隆到杆状病毒转座载体pFast Bac THa和pFast Bac THb中我角体启动子下游,构建成重组转座载体pFast Bac HTa-pg105和pFast Bac HTb-gp36,利用细菌/杆状病毒(Bac to Bac)表达系统筛选重组杆状病毒,并在昆虫细胞Sf9中表达HIV-2的gp105和gp36。结果 SDS-PAGE分析结果表明,pg105基因表达产物为-66000u糖蛋白,pg36基因则表达-41000u糖蛋白,与天然产物一致。Western blot结果显示:  相似文献   
927.
Background: Increasing numbers of patients taking oral anticoagulation are presenting for device implantation. Cessation of anticoagulation in the perioperative period may expose patients to increased risk of thromboembolic events, while continuing anticoagulation may increase the risk of bleeding. There are few guidelines or randomized controlled trials to guide perioperative management. Methods: We carried out a questionnaire‐based study of all cardiologists implanting devices in the United Kingdom to establish if there was consensus on management of anticoagulation in patients undergoing pacemaker implantation. Results: There is significant variation in management of these patients. Eighty‐nine percent of doctors stop oral anticoagulation a mean 3.7 days prior to pacemaker implantation in patients with a mechanical mitral valve, with 94% using heparin to provide preoperative anticoagulation: 58% unfractionated heparin, 40% low molecular weight heparin. The maximum accepted international normalized ratio for implantation ranged from 1.4 to 3 (median 1.8). Postoperatively, 86% restart heparin after a mean 8.5 hours. Only 11% continue oral anticoagulation throughout the implantation period. There is a hierarchy of perceived embolic risk with doctors using progressively less anticoagulation in patients with prosthetic aortic valve, high‐risk, and low‐risk atrial fibrillation. In contrast, only 7% of implanters stop theinopyridines prior to device implantation in patients with a 2‐month‐old drug eluting stent. Conclusion: Perioperative anticoagulation management of patients undergoing device procedures is currently performed with little consensus. This emphasizes the need for careful national and international audit of periprocedural anticoagulation management and its associated complications with a view to developing international consensus guidelines. (PACE 2010; 389–393)  相似文献   
928.
Background: Catheter ablation targeting of complex fractionated atrial electrograms (CFAEs) is one of the techniques used for atrial fibrillation (AF) ablation. The ablation of sites showing a high‐frequency spectral component (HFC) during sinus rhythm, known as AF nests, has been introduced as an adjunct to conventional ablation. Known locations of some AF nests are similar to CFAE sites. However, it has not been systematically evaluated whether these two targets represent the same foci. The purpose of this study was to compare the anatomical locations of these sites using an animal model of vagally mediated AF. Methods: Five anesthetized open‐chest dogs were evaluated. Atrial electrograms were obtained epicardially. AF was induced by burst atrial pacing with 20 Hz during vagal stimulation. A total of 15 sites (eight sites in right atrium and seven sites in left atrium) were evaluated in each animal. The CFAE was determined during AF according to the electrogram patterns. After sinus conversion, real‐time spectrum analysis was used for AF nest assessment at the same location. Results: The CFAE was observed at the high and mid sulcus terminalis areas, pulmonary vein antrum, and mid portion of the coronary sinus. Among them, only 60% of the CFAE sites showed HFC during sinus rhythm. In addition, some of the non‐CFAE sites (22%) showed HFC during sinus rhythm. Conclusion: The CFAE sites were not the same as the AF nests in this animal model of vagally mediated AF. Therefore, these two types of ablation methods appear to target different substrates of AF. (PACE 2010; 33:1497–1503)  相似文献   
929.
目的了解声调对鼻音功能亢进主观听感知的影响,为编制符合汉语普通话特点的鼻音功能亢进主观听感知评估材料奠定基础。方法分析20 名普通儿童与20 名腭裂儿童朗读声调不同的评估材料时,鼻音功能亢进主观听感知上的等级差异与鼻化率差异。结果不同声调材料之间,鼻音功能亢进等级及鼻化率均无显著性差异(P>0.05)。结论设计汉语普通话鼻音功能亢进主观评估材料时,可以不考虑声调的影响。  相似文献   
930.
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