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941.
942.
Extracellular matrix (ECM) scaffolds have been used to enhance anterior cruciate ligament (ACL) repair in large animal models. To translate this technology to clinical care, identifying a method which effectively sterilizes the material without significantly impairing in vivo function is desirable. Sixteen Yorkshire pigs underwent ACL transection and were randomly assigned to bridge‐enhanced ACL repair—primary suture repair of the ACL with addition of autologous blood soaked ECM scaffold—with either (i) an aseptically processed ECM scaffold, or (ii) an electron beam irradiated ECM scaffold. Primary outcome measures included sterility of the scaffold and biomechanical properties of the scaffold itself and the repaired ligament at 8 weeks after surgery. Scaffolds treated with 15 kGy electron beam irradiation had no bacterial or fungal growth noted, while aseptically processed scaffolds had bacterial growth in all tested samples. The mean biomechanical properties of the scaffold and healing ligament were lower in the electron beam group; however, differences were not statistically significant. Electron beam irradiation was able to effectively sterilize the scaffolds. In addition, this technique had only a minimal impact on the in vivo function of the scaffolds when used for ligament healing in the porcine model. © 2015 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 33:1015–1023, 2015.  相似文献   
943.
Aims:The aim was to evaluate the clinical and anatomic outcome of arthroscopic repair of type II SLAP lesions.Results:At a mean follow-up of 54-month, the mean American Shoulder and Elbow Surgeons Shoulder Index (ASES) scores improved from 52.1 preoperatively to 86.1 postoperatively (P < 0.0001) and the Simple Shoulder Test (SST) scores from 7.7 to 10.6 (P < 0.0002). Twenty-two out of the 25 patients (88%) stated that they would have surgery again. Of the 21 patients who had postoperative magnetic resonance imaging arthrographys (MRAs), 9 patients (43%) demonstrated dye tracking between the labrum bone interface suggestive of a recurrent tear and 12 patients (57%) had a completely intact repair. There was no significant difference in ASES, SST, and patient satisfaction scores in patients with recurrent or intact repairs.Conclusions:Arthroscopic repair of type II SLAP lesions demonstrated improvements in clinical outcomes. However, MRA imaging demonstrated 43% of patients with recurrent tears. MRA results do not necessarily correlate with clinical outcome.  相似文献   
944.
The utility of intravenous tissue plasminogen activator (IV t-PA) in improving the clinical outcomes after acute ischemic stroke has been well demonstrated in past clinical trials. Though multiple initial small series of endovascular stroke therapy had shown good outcomes as compared to IV t-PA, a similar beneficial effect had not been translated in multiple randomized clinical trials of endovascular stroke therapy. Over the same time, there have been parallel advances in imaging technology and better understanding and utility of the imaging in therapy of acute stroke. In this review, we will discuss the evolution of endovascular stroke therapy followed by a discussion of the key factors that have to be considered during endovascular stroke therapy and directions for future endovascular stroke trials.  相似文献   
945.
蓝旭  许建中  刘雪梅  葛宝丰 《中国骨伤》2015,28(12):1117-1120
目的:探讨胸腰段神经鞘膜瘤的影像学特点和手术治疗效果。方法:自2005年6月至2012年12月,手术治疗胸腰椎管内神经鞘膜瘤17例,其中男11 例,女6 例;年龄46~67 岁,平均53 岁;病程3~5 年,平均3.3 年。胸段患者表现为胸背痛,逐渐出现下肢麻木无力或行走不稳;腰段表现为腰背痛,下肢放射痛或感觉麻木,以及间歇性跛行。术前VAS评分 (疼痛视觉模拟标尺法) 5~8分,平均6.12分。11例患者神经功能受损,Frankel C级4例,D级5例,E级2例。CT和MRI检查提示病变部位:胸段3例,胸腰段5例,腰段3例,腰骶段6例;硬膜外5例,髓外硬膜下12例。6例单纯行椎管减压、肿瘤切除术,11例行椎管减压、肿瘤切除及后路内固定植骨融合术。结果:术中未发生大血管或脊髓损伤,术后伤口均正常愈合。17例患者术后均获随访,时间12~60 个月,平均32个月。胸背痛、腰背疼痛和下肢放射痛等显着改善,下肢麻木感明显缓解。末次随访VAS评分 0~3分,平均1.5分。神经功能受损患者末次随访Frankel分级:D级5例,E级6例。结论:MRI 是胸腰段神经鞘膜瘤有效的辅助诊断方法,影像学表现决定具体手术方法,手术目的是椎管有效减压、肿瘤彻底切除和脊柱稳定性的重建。  相似文献   
946.
目的观察不同剂量3%氯化钠溶液对老年神经外科手术患者胸腔液体含量(TFC)和血钠的影响。方法 120例拟行择期神经外科开颅手术的老年患者,随机均分为3%氯化钠溶液2ml/kg组(H1组)、3%氯化钠溶液4ml/kg组(H2组)、3%氯化钠溶液6ml/kg组(H3组)和甘露醇组(M组)。H组所有患者在麻醉诱导后30min内分别给予3%氯化钠溶液2、4、6ml/kg;M组给予20%甘露醇250ml;其后输入复方乳酸钠5 ml·kg-1·h-1。用无创阻抗仪监测入室时(基础值,T0)、麻醉诱导后(T1)、切开硬脑膜(T2)和术毕(T3)时的MAP、HR、CO、TFC,同时记录PaO2、PaCO2、pH、Na+、K+血气分析,观察脑膜张力、出血量、尿量、手术时间和拔管时间。结果与T0时比较,T1~T3四组患者MAP明显降低(P0.05),T1四组CO明显降低(P0.05),而T2时H3组、M组和T3时H3组CO明显升高(P0.05),T2时H3组、M组和T3时H3组TFC明显升高(P0.05)。与M组比较,T3时H3组CO明显升高(P0.05),T2时H1组、H2组TFC明显降低、而H3组TFC明显升高(P0.05)。与T0时比较,T1~T3四组PaO2明显升高(P0.05),T2四组PaCO2明显降低(P0.05),T3时H2组和H3组Na+明显升高(P0.05)。与M组比较,T2时H3组、T3时H2组和H3组Na+浓度明显升高(P0.05)。与H3组比较,H1组、H2组和M组脑张力为良的例数明显增加(P0.05)。与M组比较,H1组、H2组、H3组尿量明显减少(P0.05)。结论甘露醇和高渗盐具有很好的稳定血流动力学和降低颅内压的作用,但是高渗盐可显著增加CO、TFC和Na+浓度,对老年患者具有增加心肺功能负担的风险,应该谨慎使用。  相似文献   
947.
BACKGROUND: Some studies of severe asthma suggest that persistence or alteration in the pattern of inflammation may be associated with the severity of the disease. Whether there are differences in the expression of the principal cytokines and chemokines relevant to eosinophilic and neutrophilic inflammation in the airway tissues of severe compared to moderate asthmatics has not been determined. The aim of this study was to compare the patterns of expression of representative T-helper (Th) type 1 (interferon [IFN]-gamma) and Th-2 cytokines (interleukin [IL]-4, IL-5) and the neutrophil- and eosinophil-associated chemokines (IL-8 and eotaxin) in the airway tissues of patients with severe and moderate asthma. METHODS: Subjects with severe asthma (n = 24) and a comparison moderate asthma group (n = 26) were assessed using spirometry, induced sputum, exhaled nitric oxide, and bronchial biopsy. The expression of proteins of interest in the epithelium and subepithelium of the airway wall was examined by immunocytochemistry. RESULTS: Subjects with severe asthma were more symptomatic, had a lower FEV(1), and had more sputum neutrophilia (p = 0.007) and eosinophilia (p = 0.001). Exhaled nitric oxide was similar between groups. IL-8 and IFN-gamma expression were increased and IL-4 expression was decreased in severe asthma compared to moderate disease (p < 0.001 for each comparison). Eotaxin and IL-5 expression did not differ between the groups. CONCLUSION: Patients with severe asthma have increases in neutrophils and eosinophils in the sputum, and differ in airway cytokine/chemokine expression from moderate asthmatics. Excess neutrophilia may be explained by increased expression of IL-8, but differences in eosinophilia do not appear to be associated with IL-5 and eotaxin expression.  相似文献   
948.
BackgroundThe severe asthma and severe, uncontrolled asthma (SUA) populations in Japan are not well-studied. We investigated the prevalence of continuously treated severe asthma and SUA patients, their disease burden, and the treatment reality via a Japanese health insurance claims database.MethodsContinuously treated asthma patients (patients prescribed inhaled corticosteroids for asthma ≥4 times in the past year) aged ≥17 years at the index date (latest visit between April 2014 and March 2015 for asthma treatment) were included in this analysis (KEIFU study, UMIN000027695). Asthma severity and control status at the index date were defined using modified criteria of ERS/ATS guidelines. Asthma hospitalization, oral corticosteroid (OCS) use, and total medical expenses were calculated using data up to 12 months post–index date.ResultsWe identified 10,579 patients as continuously treated asthma patients. Of these, 823 (7.8%) had severe asthma; 267 (2.5%) and 556 (5.3%) patients had SUA and severe, controlled asthma (SCA), respectively. Compared with SCA and mild to moderate asthma patients, a greater percentage of SUA patients required hospitalization (13.7%, 6.2%, and 3.0%, respectively) and were prescribed OCSs (67.4%, 45.9%, and 16.2%, respectively). Yearly total medical expenses were also greater for SUA patients (mean [standard deviation]: 8346 [12,280], vs 5989 [10,483] and 3422 [8800] USD, respectively).ConclusionsThe percentages of severe asthma and SUA patients continuously treated in Japan were obtained through this large-scale analysis using a health insurance claims database. SUA patients had greater medical and economic burdens, suggesting more appropriate treatment is required according to the treatment guidelines.  相似文献   
949.
ObjectivesThe authors report the procedural and 30-day results of the PASCAL Transcatheter Valve Repair System (Edwards Lifesciences, Irvine, California) in patients with mitral regurgitation (MR) enrolled in the multicenter, prospective, single-arm CLASP study.BackgroundSevere MR may lead to symptoms, impaired quality of life, and reduced functional capacity when untreated.MethodsEligible patients had grade 3+ or 4+ MR despite optimal medical therapy and were deemed appropriate for the study by the local heart team. All outcomes were assessed through 30 days post-procedure. Major adverse events (MAEs) were adjudicated by an independent clinical events committee, and echocardiographic images were assessed by a core laboratory. The primary safety endpoint was the rate of MAEs at 30 days.ResultsBetween June 2017 and September 2018, 62 patients with grade 3+ or 4+ MR were enrolled. The mean age was 76.5 years, and 51.6% of patients were in New York Heart Association functional class III or IV, with 56% functional, 36% degenerative, and 8% mixed MR etiology. At 30 days, the MAE rate was 6.5%, with an all-cause mortality rate of 1.6% and no occurrence of stroke; 98% had MR grade ≤2+, with 86% with MR grade ≤1+ (p < 0.0001); and 85% were in New York Heart Association functional class I or II (p < 0.0001). Six-minute walk distance improved by 36 m (p = 0.0018), and Kansas City Cardiomyopathy Questionnaire and EQ-5D scores improved by 17 (p < 0.0001) and 10 (p = 0.0004) points, respectively.ConclusionsThe PASCAL repair system showed feasibility and acceptable safety in the treatment of patients with grade 3+ or 4+ MR. MR severity, irrespective of etiology, was significantly reduced and accompanied by clinically and statistically significant improvements in functional status, exercise capacity, and quality of life. (The CLASP Study Edwards PASCAL Transcatheter Mitral Valve Repair System Study; NCT03170349)  相似文献   
950.

Background

Limited intimal tears (LITs) of the aorta (Class 3 dissection variant) are the least common form of aortic pathology in patients presenting with acute aortic syndrome (AAS). LITs are difficult to detect on imaging and may be underappreciated.

Objectives

This study sought to describe the frequency, pathology, treatment, and outcome of LITs compared with other AAS, and to demonstrate that LITs can be detected pre-operatively by contemporary imaging.

Methods

The authors retrospectively reviewed 497 patients admitted for 513 AAS events at a single academic aortic center between 2003 and 2012. AAS were classified into classic dissection (AD), intramural hematoma, LIT, penetrating atherosclerotic ulcer, and rupturing thoracic aortic aneurysm. The prevalence, pertinent risk factors, and detailed imaging findings with surgical and pathological correlation of LITs are described. Management, early outcomes, and late mortality are reported.

Results

Among 497 patients with AAS, the authors identified 24 LITs (4.8% of AAS) in 16 men and 8 women (17 type A, 7 type B). Patients with LITs were older than those with AD, and type A LITs had similarly dilated ascending aortas as type A AD. Three patients presented with rupture. Eleven patients underwent urgent surgical aortic replacement, and 2 patients underwent endovascular repair. Medial degeneration was present in all surgical specimens. In-hospital mortality was 4% (1 of 24), and in total, 5 patients with LIT died subsequently at 1.5 years (interquartile range [IQR]: 0.3 to 2.5 years). Computed tomography imaging detected all but 1 LIT, best visualized on volume-rendered images.

Conclusions

LITs are rare acute aortic lesions within the dissection spectrum, with similar presentation, complications, and outcomes compared with AD and intramural hematoma. Awareness of this lesion allows pre-operative diagnosis using high-quality computed tomography angiography.  相似文献   
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