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1.
Jayaraman Chandrasekaran Embry Kyle R. Mummidisetty Chaithanya K. Moon Yaejin Giffhorn Matt Prokup Sara Lim Bokman Lee Jusuk Lee Younbaek Lee Minhyung Jayaraman Arun 《Journal of neuroengineering and rehabilitation》2022,19(1):1-13
Numerous studies showed that postural balance improves through light touch on a stable surface highlighting the importance of haptic information, seemingly downplaying the mechanical contributions of the support. The present study examined the mechanical effects of canes for assisting balance in healthy individuals challenged by standing on a beam. Sixteen participants supported themselves with two canes, one in each hand, and applied minimal, preferred, or maximum force onto the canes. They positioned the canes in the frontal plane or in a tripod configuration. Statistical analysis used a linear mixed model to evaluate the effects on the center of pressure and the center of mass. The canes significantly reduced the variability of the center of pressure and the center of mass to the same level as when standing on the ground. Increasing the exerted force beyond the preferred level yielded no further benefits, although in the preferred force condition, participants exploited the altered mechanics by resting their arms on the canes. The tripod configuration allowed for larger variability of the center of pressure in the task-irrelevant anterior–posterior dimension. High forces had a destabilizing effect on the canes: the displacement of the hand on the cane handle increased with the force. Given this static instability, these results show that using canes can provide not only mechanical benefits but also challenges. From a control perspective, effort can be reduced by resting the arms on the canes and by channeling noise in the task-irrelevant dimensions. However, larger forces exerted onto the canes can also have destabilizing effects and the instability of the canes needs to be counteracted, possibly by arm and shoulder stiffness. Insights into the variety of mechanical effects is important for the design of canes and the instructions of how to use them. 相似文献
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Kyung-Suk Suh Suk Kyun Hong Sola Lee Su young Hong Sanggyun Suh Eui Soo Han Seong-Mi Yang YoungRok Choi Nam-Joon Yi Kwang-Woong Lee 《American journal of transplantation》2022,22(1):260-265
Minimally invasive approaches are increasingly being applied in surgeries and have recently been used in living donor hepatectomy. We have developed a safe and reproducible method for minimally invasive living donor liver transplantation, which consists of pure laparoscopic explant hepatectomy and pure laparoscopic implantation of the graft, which was inserted through a suprapubic incision. Pure laparoscopic explant hepatectomy without liver fragmentation was performed in a 60-year-old man with alcoholic liver cirrhosis and hepatocellular carcinoma. The explanted liver was retrieved through a suprapubic incision. A modified right liver graft, procured from his 24-year-old son using the pure laparoscopic method, was inserted through a suprapubic incision, and implantation was performed intracorporeally throughout the procedure. The time required to remove the liver was 369 min, and the total operative time was 960 min. No complications occurred during or after the surgery. The patient recovered well, and his hospital stay was of 11 days. Pure laparoscopic living donor liver transplantation from explant hepatectomy to implantation was performed successfully. It is a feasible procedure when performed by a highly experienced surgeon and transplantation team. Further studies with larger sample sizes are needed to confirm its safety and feasibility.
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目的 筛选荔枝草治疗急性咽炎的有效部位,研究治疗急性咽炎的作用机制,为荔枝草资源的药食两用开发提供理论依据。方法 通过二甲苯致小鼠耳肿胀试验筛选荔枝草抗炎有效部位,采用氨水刺激喉部法建立大鼠急性咽炎模型,通过行为学观察、ELISA双抗夹心检测、病理形态学观察和咽部组织蛋白表达研究乙酸乙酯部位对大鼠急性咽炎的治疗效果。结果 荔枝草乙酸乙酯提取物对二甲苯致小鼠耳肿胀有明显的抑制作用,氨水刺激建立的急性咽炎模型符合急性咽炎动物模型特征,乙酸乙酯部位提取物可显著改善急性咽炎大鼠的咽部病理形态学表现。不同剂量治疗组大鼠血清及咽部组织中IL-1β、IL-6及TNF-α炎性因子数量均下降,高剂量组下降最为明显。荔枝草乙酸乙酯提取物可明显增加大鼠咽部组织IκBα蛋白表达,降低NF-κBp65蛋白表达。结论 荔枝草乙酸乙酯部位提取物对急性咽炎具有治疗作用,可能与抑制咽部炎症病理改变的发生,能调节血液中炎症因子、抑制NF-κB表达和IκBα解离有关。 相似文献
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目的 评价美国国家电器制造协会(National Electrical Manufactures Association, NEMA)最新标准(NU 2-2018)在正电子发射型计算机断层显像/电子计算机断层显像(positron emission tomography/computed tomography, PET/CT)设备性能检测中的作用。 方法 依据最新的NEMA NU 2-2018标准,检测西门子Biograph Vision PET/CT的空间分辨率、灵敏度、散射分数、计数丢失、随机符合、飞行时间分辨率、计数丢失率和随机符合校正精度、图像质量、衰减和散射校正精度及PET与CT配准精度指标。 结果 距视野中心1 cm处横向和轴向空间分辨率分别为3.75 mm和3.76 mm;在视野中心和轴向10 cm处的灵敏度分别为16.83 kcps/MBq和16.67 kcps/MBq;放射性浓度为27.37 kBq/mL时,最大等效噪声计数率为258.26 kcps,散射分数为38.58%;系统时间分辨率为209.82 ps;图像质量模型的对比度恢复系数范围为88.9%~96.2%,背景变异系数范围为2.05%~6.80%,平均肺插件残余误差为2.43%;计数丢失和随机符合校正最大误差为3.9%;距离床板末端 5 cm 和 100 cm处,在距视野中心Y轴1 cm处,PET和CT的配准精度分别为0.46 mm和1.07 mm,在距视野中心X轴20 cm处,PET和CT的配准精度分别为1.06 mm和1.45 mm,在距视野中心Y轴20 cm处PET和CT的配准精度分别为0.85 mm和1.15 mm。 结论 NEMA NU 2-2018标准检测条件更加接近临床,能更好地反映PET/CT设备的系统性能。 相似文献
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Lin Shu-I. Liao Feng-Ching Chiou Wei-Ru Lin Po-Lin Kuo Jen-Yuan Tsai Cheng-Ting Lee Ying-Hsiang 《Journal of interventional cardiac electrophysiology》2022,63(2):229-230
Journal of Interventional Cardiac Electrophysiology - 相似文献