Electrical impedance in the lower limbs of patients with Duchenne muscular dystrophy: A preliminary study

Electrical impedances were measured, at a range of frequencies from 2 to 200 kHz, in the lower limbs of nine patients with Duchenne muscular dystrophy and 12 normal subjects. The specific admittance was calculated from the impedance, based on the assumption that the shape of the part of the limb measured is a truncated cone. Curve-fitting to the admittance locus on the complex plane gave the intracellular and extracellular resistances and the membrane capacitance. The intracellular resistance was higher and the membrane capacitance was lower in the patients than in the normal subjects. The membrane capacitance in the normal subjects increased with age. In the patients, the membrane capacitance decreased, and the intracellular resistance increased with the stage of disability, which was assessed by a physician. These experimental results agree well with the theoretical explanation, which uses simplified spherical models to represent living tissue.     

等效均匀剂量优化方法在直肠癌逆向调强放疗中的应用研究

目的 比较基于等效均匀剂量生物优化与基于剂量-体积物理优化在直肠癌逆向调强治疗计划中的剂量学差异,探讨计划优化方法对计划质量的影响。方法 在已接受调强放疗的直肠癌患者中随机选取15例,采用Varian Eclipse治疗计划系统,根据不同的优化方法分别制定三种逆向调强放疗计划,其中A组采用传统的剂量-体积（Dose-volume,DV）物理优化,B组采用等效匀剂量（Equivalent uniform dose,EUD）生物优化,C组优化是在物理优化基础上增加生物优化（DV + EUD）,通过剂量学参数比较和评估三组优化方法的剂量学差异。结果 三组计划的靶区（PTV）剂量学指标无统计学差异（P > 0.05）。在保护膀胱、股骨头方面,B和C组间无统计学差异（P > 0.05）,两者均显著优于A组（P < 0.01）。在小肠方面,C组优于B组（P < 0.05）,B组显著优于A组（P < 0.01）,C组显著优于A组（P < 0.01）。结论 直肠癌调强放疗计划设计时同时使用物理和生物优化,可以在满足靶区剂量要求的前提下,更好的保护危及器官。     

An observational study of sound exposure in a single-room configured neonatal unit (SENSE study)

AimTo measure sound exposure in an Australian single-room configured, neonatal unit and compare findings to current sound level recommendations.MethodsSound meters were placed inside 51 internal environments (incubators or open cots), and within the surrounding environment of each occupied single room between September 15 and October 28, 2015. One-second incremental monitoring of decibels on an A-weighted scale (dBA), occurred over a minimum of 48 h.ResultsAll equivalent continuous sound pressure levels (L_eq) were significantly higher than the recommended 45 dBA for both incubators and open cots. Maximum sound levels (L_max) were significantly higher than the recommended 65 dBA, peaking at 126.7 dBA inside the incubator and 124.7 dBA inside the open cot. Incubators were observed to have a higher total percentage of time above 45 dBA than open cots for both day (99.84% vs. 75.59%) and night (98.66% vs. 59.56%).ConclusionSound levels exceeded the recommended maximum exposure levels outlined by the American Academy of Pediatrics (AAP). The long-term sequelae of adverse sensory exposure on preterm neurodevelopment remains unclear. Renewed attention on factors contributing to increased sound levels in neonatal units needs to be a clinical priority.     

Changes in adiposity mediate the associations of diet quality with insulin sensitivity and beta-cell function

Background and aimsTo examine the mediating role of adiposity on the associations of diet quality with longitudinal changes in insulin sensitivity and beta-cell function.Methods and resultsAdults at-risk for type 2 diabetes (T2D) in the PROMISE cohort had 4 assessments over 9 years (n = 442). Alternate Healthy Eating Index (AHEI) scores were used to assess diet quality. Generalized Estimating Equations (GEE) evaluated the associations between the AHEI and longitudinal changes in insulin sensitivity (HOMA2-%S and ISI) and beta-cell function (IGI/HOMA-IR and ISSI-2). The proportion of the mediating effect of waist circumference changes was estimated using the difference method. In the primary longitudinal analysis, AHEI was positively associated with insulin sensitivity and beta-cell function over time (% difference per standard deviation increase of AHEI for HOMA2-%S (β = 11.0, 95%CI 5.43–17.0), ISI (β = 10.4, 95%CI 4.35–16.8), IGI/HOMA-IR (β = 7.12, 95%CI 0.98–13.6) and ISSI-2 (β = 4.38, 95%CI 1.05–7.80), all p < 0.05). There was no significant association between AHEI and dysglycemia incidence (OR = 0.95, 95%CI 0.77–1.17). Adjustments for longitudinal changes in waist circumference substantially attenuated all associations of AHEI with insulin sensitivity and beta-cell function. Mediation analysis indicated that waist circumference mediated 73%, 70%, 83% and 81% of the association between AHEI and HOMA2-%S, ISI, IGI/HOMA-IR, and ISSI-2, respectively (all p < 0.01).ConclusionIn a Canadian population at-risk for T2D, AHEI score was positively associated with changes in insulin sensitivity and beta-cell function. These associations were substantially mediated by waist circumference, suggesting that changes in adiposity may represent an important pathway linking diet quality with risk phenotypes for T2D.     

福建沿海30岁以上人群臂踝脉搏波传导速度与视网膜中央动脉直径的关系

目的　探讨视网膜中央动脉直径（CRAE）反映的微循环障碍的定量参数与臂踝脉搏波传导速度（baPWV）反映的大动脉僵硬度的相关关系。方法　针对福建东南沿海大于30岁以上居民共计2　169人的横断面调查,采用问卷调查、体格检查及实验室检查获得一系列心血管危险因子。应用无创的baPWV反映大动脉僵硬度,眼底照相和半自动定量软件检测CRAE反映微血管变化及损害。结果　baPWV升高与年龄、收缩压、舒张压、MABP、脉压差、BMI、LDLC、空腹血糖等升高相关,同时与糖尿病、高血压相关。随baPWV的增大,视网膜中央动脉狭窄可能增大,该相关性独立于其他心血管危险因素。结论　baPWV增大与CRAE及其他心血管风险因子相关。该结论支持大循环与微循环相关的假设。     

舒芬太尼与芬太尼用于妇科腹腔镜手术麻醉效果观察

目的：观察等效剂量的舒芬太尼与芬太尼应用于妇科腹腔镜手术患者麻醉效果及术后不良反应。方法选择妇科行腹腔镜手术患者60例,随机分为舒芬太尼组（SF 组）及芬太尼组（F 组）,SF 组患者诱导时予舒芬太尼0,3μg∕ kg,F 组患者诱导时予芬太尼3μg∕ kg,记录麻醉诱导前（T1）、气管插管后即刻（T2）、气腹前（T3）、气腹后1min（T4）、30min（T5）以及拔除气管导管后即刻（T6）时的 SBp、DBp、HR、SpO2、pETCO2;观察并记录2组患者手术时间、清醒时间、术后疼痛及不良反应的发生情况。结果2组手术时间、苏醒时间、拔管时间比较差异无统计学意义（p ＞0,05）。2组在 T2与 T6时 SBp、DBp 均较 T1时有所升高,HR 亦有所增加,SF 组 SBp、DBp 及 HR 变化幅度均较F 组小（p ＜0,05）。2组呼吸功能比较差异无统计学意义（p ＞0,05）。SF 组患者术后 VAS 评分较 F 组显著降低（p ＜0,05）。SF 组术后躁动及呼吸抑制发生率明显较 F 组低（p ＜0,01）。2组其他不良反应比较差异无统计学意义（p ＞0,05）。结论与等效剂量的芬太尼相比,舒芬太尼用于妇科腹腔镜手术麻醉具有更高的血流动力学稳定性,在术后疼痛控制方面优于芬太尼,不良反应的发生率少于芬太尼,呼吸抑制作用比芬太尼弱。值得临床推广使用。     

两台451P型电离室剂量仪时间常数的比较研究

目的 比较2台451P型电离室剂量仪的时间常数,探讨时间响应修正公式的应用。方法 X射线机采用两个剂量率水平进行曝光,较高剂量率水平采用不同的测量模式进行测量,记录仪器测量的周围剂量当量率,根据RC电路的时间响应修正公式进行数据拟合,求出仪器的时间常数τ。结果 2台451P型电离室剂量仪0~5μSv/h量程时间常数τ值分别为（3 476.4±124.9） ms和（3 676.4±144.4） ms,0~50 μSv/h自动转换量程τ值分别为（2 051.6±249.5） ms和（2 047.0±271.9） ms,0~50 μSv/h固定量程时间常数τ值分别为（1 123.8±85.9） ms和（1 242.0±91.8） ms。结论 2台451P型电离室剂量仪的时间常数无统计学差异,但与操作手册的给定值有统计学差异,应合理选择曝光时间和测量模式进行防护检测,并使用已检定的时间常数进行响应时间修正。     

45例急性心肌梗死患者的不典型心电图分析

目的探讨急性心肌梗死（AMI）患者不典型心电图的产生原因及心电图特征。方法回顾性分析2009年1月-2010年1月间在我院诊疗的AMI并伴有不典型心电图的患者45例临床资料。结果本组不典型心电图原因中急性心肌梗死早期25例（55．56％）,其次是梗死面积较小9例（20．00％）,多部位梗死6例（13．33％）,再发心肌梗死3例（6．67％）,其他2例（4．44％）。本组不典型心电图类型中T波高而尖14例（31．11％）,其次是出现小q波12例（26．67％）,出现等电位性Q波10例（22．22％）,ST段下移5例（11．11％）,T波的演变2例（4．44％）等。结论AMI不典型心电图产生的原因以及心电图特征多种多样,临床医师应熟悉掌握、综合分析。     

Crossover studies are a better format for comparing equivalent treatments than parallel‐group studies.

Background: In controlled clinical trials the new treatment may be a slight modification of the standard or be equivalent to it with the addition of a new component. In this situation there is a positive correlation between the response to the new and the standard treatment. Objective: The influence of the correlation between the treatment responses on the statistical sensitivity of testing was studied. Randomized trials of equivalent treatments in psychiatry and hypertension research were studied for their design in relation to their level of correlation. Results: With equivalent treatments and, thus, a positive correlation a paired analysis provides better power than an unpaired one. Conclusions: Crossover studies are a better format than parallelgroup studies for comparing equivalent treatments. The scientific community is technically largely unaware of the mechanisms by which correlation levels influence or lack to influence the statistical power of controlled clinical trials.