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81.
The purposes of the present study were to examine the response of the skin blood flux (SBF) in the paralyzed lower limbs of persons with spinal cord injury (PSCI) and to clarify the relationship between the SBF and core temperature during prolonged arm exercise. Eight male PSCI with lesions from T6 to L5 and six male control subjects (CS) participated in this study. The subjects rested for 60 min and then performed arm-cranking exercise at 20 W for 30 min at 25 °C. The tympanic membrane temperature (T ty) and SBF in the anterior thigh (SBFT) and in the posterior calf (SBFC) were continuously measured throughout the experiment. The SBFC did not change in either PSCI or CS during the experiment. The SBFT in four PSCI with high lesions (T6 to T12), remained unchanged during exercise. The SBFT in the other four PSCI with low lesions (T12 to L5, SBFT+) began to elevate markedly when the T t, exceeded a threshold temperature of 36.69 °C. The pattern of increase of SBFT in SBFT+ was similar to that in CS, although onset of the increase in SBFT was delayed and the peak of SBFT during exercise was significantly lower in comparison with the CS. We consider that these differences between the SBFT+ and CS were largely attributable to the lowerT ty in the former group, which took a prolonged time to reach the threshold of 36.69 °C.  相似文献   
82.
The thermo‐adjustable hydrophilic/hydrophobic properties of AB, ABA and BAB block copolymers in which A is poly(methyl vinyl ether) (PMVE) and B is poly(isobutyl vinyl ether) (PIBVE) have been investigated. The block copolymers were prepared by “living” cationic polymerization using sequential addition of monomers. The polymerizations were carried out with the system acetal/trimethylsilyl iodide as initiator and ZnI2 as activator. The initiating system based on diethoxyethane leads to AB block copolymers whereas the initiating system based on tetramethoxypropane leads to ABA or BAB triblock copolymers. Well‐defined block copolymers of different composition with controlled molecular weights up to approx. 10 000 have been prepared. When IBVE is added to living PMVE, PIBVE‐blocks form only in the presence of an additional amount of ZnI2, which is attributed to the fact that part of the ZnI2 is inactive because of complex formation with PMVE. At room temperature, the combination of hydrophilic (PMVE) and hydrophobic (PIBVE) segments provides the copolymers with surfactant properties. Above the lower critical solution temperature (LCST) of PMVE, situated around 36 °C, the PMVE‐blocks become hydrophobic and the amphiphilic nature of the block copolymers is lost. The corresponding changes in hydrophilic/hydrophobic balance have been evaluated by investigation of the emulsifying properties of the block copolymers for water/decane mixtures as a function of the temperature. Below the LCST, the block copolymers have emulsifying properties similar to or better than those of the commercial PEO‐PPO block copolymers (Pluronic®). Either oil‐in‐water or water‐in‐oil emulsions can be obtained, depending on the polymer architecture and the water/decane volume ratio. The emulsifying properties are strongly reduced or completely lost above 40 °C. Emulsions obtained with a PMVE36b‐PIBVE54 block copolymer for a water/decane (v/v) ratio of 85/15 remained stable for more than six months.

50/50 and a 85/15 water/decane w/o emulsion (15 g/l) with the PMVE36b‐PIBVE54 block copolymer at 20 °C.  相似文献   

83.
目的 简化人体上肢结构,建立两刚体系统动力学模型,并对其进行数值求解。方法 以卡尔登角为广义坐标,运用多刚体动力学理论,建立上肢的动力学方程;运用MATHEMATICA计算软件对方程进行正、反数值求解并进行了比较。结果 得到了上肢的两刚体动力学方程和数值解,对比计算结果表明,将已知运动带入方程求得的主动力作为已知力反求得的卡尔登角与已知运动的卡尔登角基本一致,而且在反解时会出现奇点。结论 运用MATHEMATICA计算软件求解复杂的上肢两刚体系统方程,相当方便,为免奇点出现,应在适当范围内进行求解,在误差允许的范围内,求得的解是可以接受的。  相似文献   
84.
诱发电位(EP)信号榆测与分析技术是临床医学诊断神经系统损伤及病变的重要手段之一。传统的EP信号提取与分离方法中,通常认为EP信号中混入的EEG等噪声是高斯分布的。近年来一些研究表明TEEG信号具有一定的非高斯特性。α-稳定分布町以更好地描述实际应用中所遇到的具有显著脉冲特性的EEG噪声。文中简要介绍了稳定分们统计特性,推导了一种适用于EP信号分离提取的新算法。计算机模拟和分析表明,这种算法是一种在分数低阶α稳定分布背景噪声条件下具有良好韧性的EP信号分离提取方法。  相似文献   
85.
Clostridium difficile infection (CDI) remains a major public health issue, and fecal microbiota transplantation (FMT) has become one of the standard therapies for recurrent or refractory CDI. When compared to medical therapies, such as metronidazole or vancomycin, FMT has a high rate of treatment response with acceptable safety and efficiency. Following promulgation of the amendments in September 2018 in Taiwan, FMT has been indicated for recurrent or refractory CDI. The Taiwan Microbiota Consortium contributed to the Taiwan FMT Expert Consensus, which established basic norms and stipulated essential principles, including the indications for transplantation, eligible locations and personnel, donor screening policies, fecal sample handling, and post-FMT follow-up. However, establishing an eligible FMT team in a qualified hospital remains a clinical challenge, and the requirement for facilities and well-screened donors impedes the implementation of FMT. In this review, we aim to provide domestic FMT teams with explicit instructions to facilitate realization and increase the practice of FMT. Based on the Taiwan FMT Expert Consensus and current regulations, we performed a literature review and integrated the experiences of Taiwanese multidisciplinary experts into this article. The content intends to offer clinicians up-to-date evidence and highlight the essential points of FMT.  相似文献   
86.
87.
We report an adult male cadaver with persistence of the ductus arteriosus and a right retroesophageal artery. The retroesophageal artery was first appreciated as a retropharyngeal mass during the dissection of this area. Both the left and right vertebral arteries originated in normal fashion. The thoracic duct of our specimen drained into the junction of the left internal jugular and left subclavian veins. We believe this to be the first report of simultaneous right retroesophageal subclavian artery and patent ductus arteriosus. The anatomy and embryology of these two anomalies in the same specimen are discussed.  相似文献   
88.
 目的 了解2014—2018年海南地区各级医院住院患者医院感染现患率情况,为降低海南地区医院感染发病率提供科学指导依据。方法 采用横断面调查法对2014、2016和2018年参与海南省医院感染现患率调查日的住院患者进行床旁调查和病历调查,调查数据采用SPSS 20.0软件进行统计分析。结果 2014、2016、2018年分别调查患者17 497、18 509、22 705例,医院感染现患率为1.88%~3.26%,呈下降趋势(P<0.001);三年共计感染部位1 612例次,以下呼吸道感染(813例次,50.43%)和泌尿道感染(242例次,15.01%)为主;综合ICU是医院感染现患率最高的科室(22.46%~34.53%)。共检出病原菌892株,以革兰阴性菌为主(664株,74.44%),主要为铜绿假单胞菌(169株,18.95%)和大肠埃希菌(122株,13.68%),金黄色葡萄球菌是占比最高(48株,5.38%)的革兰阳性菌。三年抗菌药物使用率为32.87%~34.95%,呈下降趋势(P=0.001)。结论 尽管海南地区医院感染现患率有所下降,但仍需在今后的工作中加强重点科室、部位、环节及高危人群的防控管理力度,逐步降低医院感染发病率。  相似文献   
89.
 目的 构建基于少数类样本合成过抽样技术(synthetic minority over-sampling technique,SMOTE)算法的化学治疗(化疗)肿瘤患者下呼吸道感染预警模型。方法 共纳入西宁市4所三级医院2019年1月-2021年6月收治的2 384例接受化疗的肿瘤患者为研究对象,将所收集病例按照7:3的比例随机分为建模组1 668例和验证组716例,建模组数据用来建立模型,验证组数据对所建立的模型进行验证,利用单因素比较和logistic回归分析筛选下呼吸道感染影响因素,基于SMOTE算法建立化疗肿瘤患者下呼吸道感染预警模型。结果 logistic回归分析可得,年龄(x1)、身体质量指数(BMI)值是否正常(x2)、恶性肿瘤分期(x3)、吸烟史(x4)、合并糖尿病(x5)、合并肺部疾病(x6)均是化疗肿瘤患者下呼吸道感染的危险因素(均P<0.01),获得原始数据预警模型:Logit(P)=0.055x1+0.967x2-0.195x3+1.383x4+0.968x5+0.939x6-14.073和基于SMOTE算法的预警模型:Logit(P)=0.090x1+1.092x2-0.249x3+1.724x4+1.136x5+1.344x6-14.859。基于SMOTE算法预警模型AUC为0.949(95%CI:0.937~0.961),高于原始数据预警模型AUC 0.780(95%CI:0.734~0.846)。结论 基于SMOTE算法所构建的预警模型能更准确预警化疗肿瘤患者下呼吸道感染,有效解决感染与非感染患者样本数据不平衡所导致的预测误差,基于预测模型可选择相应的对策进行应对。  相似文献   
90.
随着我国医疗器械技术的发展,上下肢康复机器人作为一种新型的医疗器械出现在大众面前,很大程度上替代了传统的康复训练,提高了康复训练的效率。但是上下肢康复机器人的出现也伴随着一些问题,文章结合上下肢康复机器人的一些标准及广东省医疗器械质量监督检验所近年来对上下肢康复机器人的检测情况进行探讨,并提出一些问题和建议,以期能够规范上下肢康复机器人的市场和提高上下肢康复机器人的产品质量。  相似文献   
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