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31.
《Clinical neurophysiology》2019,130(9):1562-1569
ObjectiveConventional deep brain stimulation (DBS) systems with ring-shaped leads generate spherical electrical fields. In contrast, novel directional leads use segmented electrodes. Aim of this study was to quantify the impedance variations over time in subjects with the directional Cartesia-Boston® system.MethodsImpedance records, programming settings, and clinical data of 11 consecutive Parkinsonian patients implanted with DBS directional leads in two Italian centers (Udine and Vicenza) were retrospectively evaluated. Data were collected before starting stimulation (in the operating room and at days 5 and 40) and after switching stimulation on at the successive follow-up visits (1, 6 and 12 months).ResultsDirectional leads have significantly higher impedance than ring leads. Stimulated contacts had always lower impedance compared to non-stimulated contacts. Before DBS-on, all contacts had higher impedance in the operating room, with an initial decrease five days post-surgery and a subsequent increase at day 40, more evident for directional contacts. The impedance of directional leads increased post-implantation at 1 and 6 months with a plateau at 12 months.ConclusionsThere was a significant difference between the directional and ring leads at baseline (before activation of DBS) and during follow-up (chronic DBS).SignificanceOur study reveals new information about the impedance of segmented electrodes that is useful for patient management during the initial test period, as well as during long-term DBS follow-up. 相似文献
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《Journal of Medical Imaging and Radiation Sciences》2020,51(1):173-181
IntroductionThis study aims to construct learning curves related to the realization of standardized postprocessing by radiographer students and to discuss their exploitation and interest.Materials and MethodsThis study was carried out in 21 French students in their 3rd year of training. Two postprocessing protocols in CT (#1 traumatic shoulder; #2 petrous bone) were repeated 15 times by each student. Each achievement was timed to obtain overall learning curves. The realization accuracy was also assessed for each student at each repetition.ResultsThe learning rates for the two protocols are 63% and 56%, respectively. The number of repetitions to reach the reference time for each protocol is 11 and 12, respectively. In both protocols, the standard deviations are significantly reduced and stabilized during repetitions. The mean accuracy progresses more quickly in protocol #1.DiscussionThe measured learning rates reflect a rapid learning process for each protocol. The analysis of the standard deviations shows that students have reached a homogeneous level. The average times and accuracies measured during the last repetitions show that the group has reached a high level of performance. Building learning curves helps students measure their progress and motivates them.ConclusionObtaining learning curves allows trainers/supervisors to qualify the learning difficulty of a task while motivating students/radiographers. The use of learning curves is inline with the competency-based training paradigm. 相似文献
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背景与目的:甲状腺乳头状癌(papillary thyroid carcinoma,PTC)和桥本甲状腺炎(Hashimoto’s thyroiditis,HT)的发病率均呈上升趋势,两者之间的关系已成为目前研究的热点。探讨PTC和HT之间的关系。方法:回顾性分析2014—2015年期间在中国科学院大学附属肿瘤医院头颈肿瘤外科行甲状腺癌手术治疗的首诊患者306例,术后病理学检查均明确诊断为PTC,其中术后病理学确诊伴发HT者42例,比较伴发HT与未伴发HT患者的临床病理学特征。结果:PTC患者女性发病年龄高于男性(46.2岁 vs 41.9岁)。相较于与未伴发HT的PTC患者,伴发HT的患者中女性比例更高(93% vs77%),中央区淋巴结数目较多[(5.0±3.4)枚 vs (2.5±2.7)枚],术前促甲状腺激素(thyroid-stimulating hormone,TSH)水平较高[(3.28±1.91)μU/mL vs (2.12±1.29)μU/mL],术前抗甲状腺过氧化物酶抗体(thyroid peroxidaseantibody,TPOAb)阳性率较高(55% vs 14%),术前甲状腺球蛋白抗体(thyroglobulin antibodies,TgAb)阳性率较高(69% vs 13%)。发生中央区淋巴结转移的患者中,中央区淋巴结转移数目与中央区淋巴结总数显著相关(Pearson相关系数=0.582)。多因素logistic回归分析发现,男性、低龄、被膜侵犯是PTC患者中央区淋巴结转移的独立危险因素。结论:伴发HT对PTC患者的预后无显著影响。伴发HT的PTC患者TSH水平显著偏高,提示HT可能是PTC发病风险因素之一。中央区淋巴结转移数目与中央区淋巴结总数相关,推测PTC淋巴结转移可能与淋巴结炎症反应相关。 相似文献
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目的探讨聪耳通窍汤联合耳针治疗老年神经性耳鸣患者的近远期疗效。方法选取耳鼻喉科门诊收治的老年神经性耳鸣患者136例,按随机数字表法分组,对照组68例予以耳针治疗,研究组68例在对照组基础上予以聪耳通窍汤治疗。检测比较两组间近、远期临床疗效、甲襞微循环指标、血液流变学指标以及不良反应发生率。结果治疗后,对照组总有效率为67.64%(46/68)低于研究组总有效率83.82%(57/68),具有统计学意义(P<0.05);随访6个月后,对照组总有效率64.71%(44/68)低于研究组总有效率89.71%(61/68),具有统计学意义(P<0.05);与对照组比较,研究组治疗后甲襞微循环襻周积分、管襻积分、流态积分及总积分较低,治疗后血浆黏度、高切全血黏度、低切全血黏度及红细胞压积较低,差异具有统计学意义(P<0.05);治疗中出现的不良反应为恶心、腹胀、针刺部位疼痛,两组间不良反应发生率无统计学差异(P>0.05)。结论聪耳通窍汤联合耳针治疗老年神经性耳鸣患者的近远期疗效均较好,能明显改善患者微循环状态及血液流变学指标,减轻内耳循环障碍,具有较高安全性。 相似文献
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《Digestive and liver disease》2020,52(4):420-426
BackgroundManagement of inflammatory bowel diseases (IBD) in the emergency department is often suboptimal.AimsTo develop a national consensus checklist of indicators to facilitate decision-making in emergency departments concerning hospitalisation and referral for abdominopelvic computed tomography (CT).MethodsA Delphi survey was used to obtain consensus on a checklist of clinical and biological variables. 119 healthcare professionals experienced in treating IBD were invited to participate. Panellists were provided with a literature survey and invited to agree or disagree with items on a prototype checklist. Two successive rounds of voting were organised.ResultsThe prototype checklist included fifteen clinical or laboratory indicators for hospitalisation or CT. Four indicators were not retained in the Delphi process and four additional indicators added. The final indicators retained were: abdominal signs/symptoms of disease exacerbation, intravenous morphine titration, fever, vomiting, dehydration, recent intestinal surgery, ano-perineal abscess, bowel obstruction, haemodynamic instability, anaemia, acute kidney failure and elevated C-reactive protein. Consensus for the retained indicators was >88%.ConclusionsUse of this consensus checklist for the management of IBD in the emergency department may help improve standards of care and thus reduce the burden of these diseases. 相似文献