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91.
Normocapnic hyperoxic and hypercapnic hyperoxic gas challenges are increasingly being used in cerebrovascular reactivity (CVR) and calibrated functional MRI experiments. The longitudinal arterial blood water relaxation time (T1a) change with hyperoxia will influence signal quantification through mechanisms relating to elevated partial pressure of plasma‐dissolved O2 (pO2) and increased oxygen bound to hemoglobin in arteries (Ya) and veins (Yv). The dependence of T1a on Ya and Yv has been elegantly characterized ex vivo; however, the combined influence of pO2, Ya and Yv on T1a in vivo under normal ventilation has not been reported. Here, T1a is calculated during hyperoxia in vivo by a heuristic approach that evaluates T1‐dependent arterial spin labeling (ASL) signal changes to varying gas stimuli. Healthy volunteers (n = 14; age, 31.5 ± 7.2 years) were scanned using pseudo‐continuous ASL in combination with room air (RA; 21% O2/79% N2), hypercapnic normoxic (HN; 5% CO2/21% O2/74% N2) and hypercapnic hyperoxic (HH; 5% CO2/95% O2) gas administration. HH T1a was calculated by requiring that the HN and HH cerebral blood flow (CBF) change be identical. The HH protocol was then repeated in patients (n = 10; age, 61.4 ± 13.3 years) with intracranial stenosis to assess whether an HH T1a decrease prohibited ASL from being performed in subjects with known delayed blood arrival times. Arterial blood T1a decreased from 1.65 s at baseline to 1.49 ± 0.07 s during HH. In patients, CBF values in the affected flow territory for the HH condition were increased relative to baseline CBF values and were within the physiological range (RA CBF = 36.6 ± 8.2 mL/100 g/min; HH CBF = 45.2 ± 13.9 mL/100 g/min). It can be concluded that hyperoxic (95% O2) 3‐T arterial blood T1aHH = 1.49 ± 0.07 s relative to a normoxic T1a of 1.65 s. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
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《Seminars in immunology》2015,27(6):369-378
Macrophages are important for tissue development, homeostasis as well as immune response upon injury or infection. For a long time they were only seen as one uniform group of phagocytes with a common origin and similar functions. However, this view has been challenged in the last decade and revealed a complex diversity of tissue resident macrophages. Here, we want to present the current view on macrophage development and tissue specification and we will discuss differences as well as common patterns between heterogeneous macrophage subpopulations.  相似文献   
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目的: 探讨应用多反转时间动脉自旋标记(multiple inversion time-pulsed arterial spin labeling,mTI-ASL)和体素内不相干运动(intravoxel incoherent motion,IVIM)技术在脑胶质瘤术后复发与假性进展中的鉴别价值。方法: 选择2018年01月至2020年01月就诊于我院高级别胶质瘤术后放化疗后首次复查常规MR增强扫描出现异常强化的患者,行mTI-ASL及IVIM序列扫描,将获取图像数据资料进行相关后处理分析,分别手动勾画感兴趣区,测量术后异常强化区各项定量参数,即真性扩散系数(true diffusion coefficient,D)、假性扩散系数(pseudo-diffusion coefficient,D*)及灌注分数(perfusion fraction,f)、脑血流量(cerebral blood flow,CBF)和动脉通过时间(arterial transit time,ATT)。分别采用独立样本t检验比较两组感兴趣区相关参数值,从而评估mTI-ASL和IVIM技术在两者鉴别诊断中的价值。结果: (1)脑胶质瘤术后复发组CBF值(6.413±0.438)、ATT值(0.198±0.033),比假性进展组CBF值(4.654±0.372)、ATT值(0.165±0.208)高,两者比较具有统计学意义(P<0.01)。(2)脑胶质瘤术后复发组D值(1.118±0.178),比假性进展组D值(1.380±0.236)低,两者比较具有统计学意义(P<0.01)。(3)脑胶质瘤术后复发组D*值(17.126±4.274)、f值(0.269±0.095),比假性进展组D*值(12.755±3.974)、f值(0.169±0.052)高,两者比较具有统计学意义(P<0.01)。结论:应用 mTI-ASL和IVIM技术有助于脑胶质瘤术后复发与假性进展的鉴别诊断。  相似文献   
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目的: 通过品管圈活动降低静脉用药调配中心(pharmacy intravenous admixture services, PIVAS)的贴签差错率。方法: 以自愿的方式组成品管圈小组,经过辅导员专业培训后,按照十大品管步骤开展活动。运用了柏拉图,柱状图,鱼骨图,雷达图等多种方法,依据二八原则分析干预重点,并通过头脑风暴制定干预措施。结果: 干预前贴签差错35件/月,干预后降至12件/月,达到了目标值12.62件/月,达标率为102.77%。结论: 通过品管圈活动的方法从管理方面入手能够深入发掘和分析贴签差错,有效降低了贴签差错率,确保患者用药安全。  相似文献   
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BackgroundThis study aims to compare the use of one-per-mil tumescent solution (a mixture of epinephrine and 0.2% lidocaine in a ratio of 1:1,000,000 in normal saline solution) and tourniquet to create clear operative fields and to evaluate the functional outcomes after post burn hand contracture surgery.MethodsThe subjects of this randomized controlled trial were divided into one-permil tumescent technique and tourniquet group for a similar surgical procedure. Three independent assessors evaluated the clarity of the operative fields through recorded videos for the first 15 min and the first 10-minute of each hour of the surgery. Functional outcome was evaluated at least three months postoperatively using total active and passive motion (TAM and TPM) of each digit. Malondialdehyde (MDA) and tumor necrosis factor alpha (TNF-α) were tested during baseline (5 min before the procedures), ischemia phase, and reperfusion phase (a phase when the blood flow returned to the tissue).Results35 subjects were included in this study: 17 in the tumescent group and 18 in the tourniquet group. We found a significant difference in the clarity of operative field between tumescent and tourniquet groups, 5 vs 35 bloodless operative fields, respectively (p < 0.05). TAM and TPM of each digit before surgery and 3 months postoperatively showed no significant difference between both groups (p > 0.05). Furthermore, we found no difference in MDA and TNF-α levels between both groups at their respective phases.ConclusionsThe use of one-per-mil tumescent technique does not replace tourniquet use to create bloodless operative fields in burned hand contracture surgery. However, the postoperative functional results were similar in both groups showing that tumescent technique can be used as an alternative to tourniquet without compromising outcomes. The MDA and TNF-α examinations do not provide conclusive outcomes regarding ischemia and reperfusion injury.  相似文献   
97.
BackgroundTotal knee arthroplasty requires careful surgical technique to attain the goal of a well-aligned and symmetrically balanced knee. Soft tissue balance and correct femoral component rotation are paramount in achieving these goals. The two competing techniques to select femoral component rotation and soft tissue balance are the gap balance technique and the measured resection technique.MethodsWe performed a randomized, prospective study to compare the two techniques in patients undergoing simultaneous bilateral total knee arthroplasty, whereby one technique was performed in each knee. Fifty (50) subjects were enrolled into the study. The inclusion criteria were osteoarthritic varus knee deformities with similar deformities in both knees. Subjects were followed up for a minimum of two years.ResultsThe knees balanced via the gap balance technique had significantly more posterior medial bone removed from the femur than those knees balanced via the measured resection technique (P < .001). Knees in the gap balance group tended to require more medial knee releases in extension and tended to have smaller sized femoral components as a result of cutting more bone from the femur in flexion. The modular tibial polyethylene bearing tended to be thicker in the gap balance group. Despite these differences, average knee flexion and functional revised Oxford Knee Scores at 2-year follow-up were not statistically different.ConclusionAt 2-year follow-up, there were no differences between the function and scores using the two techniques. Long-term follow-up will be necessary to evaluate any differences in long-term durability.  相似文献   
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目的 观察中医手法介入Rood技术(多种感觉刺激治疗法或皮肤感觉输入促通技术)联合神经肌肉低频电刺激仪治疗脑卒中后遗症面瘫的临床疗效。方法 选取明显由于脑卒中导致面瘫后遗症状的患者60例,随机分成中医手法介入Rood技术联合神经肌肉低频电刺激仪治疗组(试验组)和Rood技术联合神经肌肉低频电刺激仪治疗组(对照组)。治疗组同时在相关部位皮肤的特殊区域施加中医手法介入Rood技术联合神经肌肉低频电刺激仪的治疗。治疗前后对脑卒中后遗症面瘫患者进行评定,参照国家中医药管理局颁布《中医病症诊断疗效标准》及症状量表的相关内容,结合面神经功能分级(MHBN)。结果 治疗后根据评定均得到明显改善,尤其治疗组(试验组)改善更加显著,与对照组疗效差异有统计学意义(P<0.05)。结论 中医手法介入Rood技术联合神经肌肉低频电刺激仪能够很大程度的恢复脑卒中后遗症面瘫患者的面部功能,有效改善患者的面部进食状况,提高患者的日常生活水平。  相似文献   
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