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Central illustration: cumulative major adverse cardiac events (MACE) and bioresorbable vascular scaffold (BVS) thrombosis rates after 1, 2, 3, 4 and 5 years.
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PurposeTo retrospectively evaluate the safety and effectiveness of the Covera stent graft (SG) for the treatment of dysfunctional or thrombosed arteriovenous grafts (AVGs).Materials and MethodsWithin 29 months (February 2016–August 2018), 79 patients underwent Covera SG placement in the authors’ department for the treatment of dysfunctional AVGs. Data were available for 64 patients who underwent 64 procedures, using 64 devices. Minimum follow-up was 6 months, unless reintervention occurred. Mean follow-up was 277 days (6–923 days). Treatment characteristics were 51 cases with venous-graft anastomosis (VGA) stenosis (79.7%), 13 cases of puncture zone stenosis (20.3%), 14 cases of in SG stenosis (21.9%), 8 cases of pseudoaneurysm treatment (12.5%) (1 treatment area might have had more than 1 characteristic). Thirty-six patients presented with thrombosis (56.2%), and 31 of 64 case were de novo treatment areas (48.4%). Primary outcome measurements were technical success and post-intervention primary patency (PIPP) at 6 months, whereas secondary outcome measurements included factors influencing primary outcome.ResultsTechnical success was 100%. Median PIPP was 336 days, and 73.6% of treatment areas were patent at 6 months. There were no significant differences in terms of PIPP when de novo treatment areas were compared with restenotic areas (519 vs. 320 days, respectively; P = .1); patients who presented with versus those who presented without thrombosis (320 vs. 583 days, respectively; P = .07); puncture zone stenosis or elsewhere (329 vs. 686 days, respectively; P = .52); and VGA stenosis or elsewhere (336 vs. 335 days, respectively; P = .9).ConclusionsUse of the Covera SG for AVG treatment was safe and effective in every type of treatment area presented in this retrospective analysis.  相似文献   
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《Molecular immunology》2015,68(2):492-500
Although intranasal vaccination has been shown to be effective for the protection against inhalational anthrax, establishment of long-term immunity has yet to be achieved. Here, we investigated whether intranasal immunization with recombinant protective antigen (rPA) of Bacillus anthracis induces immunological memory responses in the mucosal and systemic compartments. Intranasal immunization with rPA plus cholera toxin (CT) sustained PA-specific antibody responses for 6 months in lung, nasal washes, and vaginal washes as well as serum. A significant induction of PA-specific memory B cells was observed in spleen, cervical lymph nodes (CLNs) and lung after booster immunization. Furthermore, intranasal immunization with rPA plus CT remarkably generated effector memory CD4+ T cells in the lung. PA-specific CD4+ T cells preferentially increased the expression of Th1- and Th17-type cytokines in lung, but not in spleen or CLNs. Collectively, the intranasal immunization with rPA plus CT promoted immunologic memory responses in the mucosal and systemic compartments, providing long-term immunity.  相似文献   
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BackgroundResearchers have proposed that impaired sleep may be a causal link in the progression from Mild Cognitive Impairment (MCI) to Alzheimer's Disease (AD). Several recent findings suggest that enhancing deep sleep (N3) may improve neurological health in persons with MCI, and buffer the risk for AD. Specifically, Transcranial Electrical Stimulation (TES) of frontal brain areas, the inferred source of the Slow Oscillations (SOs) of N3 sleep, can extend N3 sleep duration and improve declarative memory for recently learned information. Recent work in our laboratory using dense array Electroencephalography (dEEG) localized the sources of SOs to anterior limbic sites – suggesting that targeting these sites with TES may be more effective for enhancing N3.MethodsFor the present study, we recruited 13 healthy adults (M = 42 years) to participate in three all-night sleep EEG recordings where they received low level (0.5 mA) TES designed to target anterior limbic areas and a sham stimulation (placebo). We used a convolutional neural network, trained and tested on professionally scored EEG sleep staging, to predict sleep stages for each recording.ResultsWhen compared to the sham session, limbic-targeted TES significantly increased the duration of N3 sleep. TES also significantly increased spectral power in the 0.5–1 Hz frequency band (relative to pre-TES epochs) in left temporoparietal and left occipital scalp regions compared to sham.ConclusionThese results suggest that even low-level TES, when specifically targeting anterior limbic sites, can increase deep (N3) sleep and thereby contribute to healthy sleep quality.  相似文献   
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学习困难儿童智力及记忆力特征分析   总被引:4,自引:3,他引:1  
目的探讨学习困难儿童的智力、记忆力特征。方法学习困难(LD)根据ICD-10五条诊断标准,精神发育迟滞(MR)根据国际疾病分类第10版(ICD-10)诊断标准,分为实验组LD组;对照组a.正常组,b.弱智组。采用中国韦氏儿童智力量表进行智力测验,记忆力测验采用中国科学研究院编制的临床记忆量表。结果LD组与正常对照组在语言智商、操作智商、总智商[(86.23±10.65)分,(87.44±12.59)分,(84.09±13.96)分vs(102.27±10.21)分,(103.22±11.65)分,(103.28±9.88)分]及分测验值差异均有显著性(P<0.01);LD组儿童VIQ与PIQ相距一个标准差以上的比率明显高于对照组(2=9.29,P<0.01),也较MR对照组多(2=4.29,P<0.05)。LD组记忆商(MQ)明显低于正常对照组(P<0.01)。结论LD儿童智商、记忆商水平低于正常儿童,且存在明显智力结构发展不平衡。  相似文献   
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目的 :通过观察实验犬下腔静脉内放置可扩张性内支撑后血管的形态学变化 ,确定支撑的内皮化进程 ,以期为临床减少内支撑阻塞、合理应用抗凝剂提供组织学的依据。  方法 :在 14只杂种犬下腔静脉内放置金属内支撑 ,于术后 1个月起 ,逐月取下腔静脉作光镜和电镜检查。  结果 :术后 1个月左右 ,内支撑基本内皮化 ,5个月完成血管的重构。  结论 :早期抗凝治疗是防止内支撑阻塞的关键 ,首次提出内支撑放置后血管重构的现象  相似文献   
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