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941.
Töres Theorell MD PhD Sarah Knox PhD Jan Svensson PhD Dick Waller MA 《Behavioral medicine (Washington, D.C.)》2013,39(1):36-41
Abstract During an ordinary work day blood pressure was self-monitored once every hour in two samples of asymptomatic nonmedicating 28-year-old men. They were selected on the basis of previous compulsory blood pressure recordings made at the age of 18 when they had been drafted for military service. Subjects in the ?original hypertensive sample” with ?strain” occupations (hectic and uncontrollable, such as waiter, driver and cook) had more marked elevations of systolic blood pressure during work hours than other subjects. 相似文献
942.
943.
《Gait & posture》2021
BackgroundAssessing postural stability in Parkinson’s disease (PD) often relies on measuring the stepping response to an imposed postural perturbation. The standard clinical technique relies on a brisk backwards pull at the shoulders by the examiner and judgement by a trained rater. In research settings, various quantitative measures and perturbation directions have been tested, but it is unclear which metrics and perturbation direction differ most between people with PD and controls.Objectives(1) Use standardized forward vs. backward perturbations of a support surface to evaluate reactive stepping performance between PD and control participants. (2) Evaluate the utility of using principal components analysis to capture the dynamics of the reactive response and differences between groups.MethodsSixty-two individuals participated (40 mild-to-moderate PD, off medication). Standardized rapid translations of the support surface were applied, requiring at least one step, backward or forward, to restore balance. The number of steps taken and the projection of the first principal component (PC1) of the center of pressure (COP) time series were entered in linear repeated-measures mixed effect models.ResultsForward falls required significantly fewer steps to recover than backward falls. PC1 captured more than half of the variance in the COP trajectory. Analysis of the PC1 projection revealed a significant interaction effect of group (PD vs. controls) by direction, such that there was a group difference in forward stepping, but not backward.SignificanceForward reactive stepping in PD differed from controls more than backward-stepping. PC1 projections of the COP trajectory capture the dynamics of the postural response and differ between PD and controls. 相似文献
944.
《Gait & posture》2021
BackgroundIntegration of visual, vestibular, and proprioceptive sensations contributes to postural control. People with peripheral visual field loss have serious postural instability. However, the directional specificity of postural stability and sensory reweighting caused by gradual peripheral visual field loss remain unclear.Research questionWhat are the effects of peripheral visual field loss on static postural control?MethodsFifteen healthy young adults participated in this study. The participants were asked to stand quietly on a foam surface. Three conditions of virtual visual field loss (90°, 45°, and 15°) were provided by a head-mounted display, and ground reaction forces were collected using a force plate to calculate the displacements of the center of pressure (COP).ResultsThe root mean square (RMS), mean velocity, and 95% ellipse area of COP displacements in the horizontal plane increased, and RMS in the anteroposterior (AP) direction was unchanged under the smallest visual field condition compared to the largest one. The power spectrum density of COP displacements in the low-frequency band was decreased and that in the medium-frequency band was increased in the AP direction.SignificanceDuring quiet standing of young healthy adults with peripheral visual field loss, increased peripheral visual field loss resulted in lower postural stability. Postural stability in the AP direction was maintained contrary to the functional sensitivity hypothesis. Peripheral visual field loss reduced the weighting of the visual input and increased that of the vestibular input in the AP direction to maintain equilibrium. 相似文献
945.
目的 探讨G蛋白β3亚单位C825T基因多态性与富马酸比索洛尔降压疗效的相关性。方法 选择2018-10至2020-10在解放军总医院第一医学中心心内科住院或门诊就诊的轻、中度原发性高血压患者,均口服5 mg/d比索洛尔,进行GNβ3-C825T基因型测定,依据基因型分为3组:CC组、CT组、TT组,每组150例,在3组受试者治疗7 d,1、3、6个月后进行随访,测定患者的富马酸比索洛尔药物代谢血药浓度;治疗前、治疗7 d,1、3、6个月后进行24 h动态血压监测,比较患者静息状态下收缩压及舒张压(SBP、DBP),24 h收缩压均数(24 h SBP)、24 h舒张压均数(24 h DBP)、白天收缩压均数(d SBP)、白天舒张压均数(d DBP)、夜间收缩压均数(n SBP)、夜间舒张压均数(n DBP)的组间差异;进行24 h动态心电图监测,比较24 h平均心率、窦性心律震荡水平。结果 治疗7 d,随访1、3、6个月TT组富马酸比索洛尔血药浓度均高于CC组及CT组,差异均有统计学意义(P<0.05),CC组与CT组无统计学差异,3组组内不同时间血药浓度变化均无统计学差异;应用富马酸比索洛尔后,3组患者血压均有下降趋势,其中TT组降压效果>CT组>CC组,3组间血压下降水平有统计学差异(P<0.05);治疗7 d后,动态心电图显示:3组患者心率有下降趋势,TT组>CT组>CC组,其中TT组与CT组、CC组比较有统计学差异(P<0.05),CT组与CC组心率下降无统计学差异;TT组窦性心律震荡水平优于CT组、CC组。结论 G蛋白β3亚单位C825T基因多态性与富马酸比索洛尔降压疗效之间具有相关性。 相似文献
946.
目的 探讨经皮气管切开术在神经重症患者中应用的临床价值。方法 回顾分析医院2015-01至2018-05收治并行气管切开的69例神经重症病例,按气管切开方式分为经皮扩张气管切开术(percutaneous dilatational tracheostomy,PDT,n=48) 组和常规气管切开(open surgical tracheostomy,ST,n=21)组,比较两组操作时间、血流动力学指标、颅内压(intracranial pressure,ICP)的波动及早期并发症的差异。结果 PDT组手术时间为(7.1±1.5)min,ST组为(13.5±4.9)min,ST组长于PDT组(P<0.05);ICP波动两组差别无统计学意义;血流动力学指标两组差别无临床意义。结论 PDT对神经重症患者的血流动力学及ICP影响较ST无明显差异,操作时间更短,可作为首选气管切开方法。 相似文献
947.
Hepatocellular carcinoma is the main liver-related cause of death in patients with compensated cirrhosis. The early phases are asymptomatic and the prognosis is poor, which makes prevention essential. We propose that non-selective beta-blockers decrease the incidence and growth of hepatocellular carcinoma via a reduction of the inflammatory load from the gut to the liver and inhibition of angiogenesis. 相似文献
948.
949.
《Journal of medical engineering & technology》2013,37(3):213-219
AbstractPressure mapping techniques are used in wheelchair and seating services to assess posture and assist in the prevention and treatment of pressure ulcers. The Force Sensitive Application (FSA) pressure mapping systems in Wales have a high clinical use and frequent calibration is required. This project aimed to assess the performance of the systems and develop a calibration strategy. Testing of the systems was spilt into three stages. The pilot stage compared different calibration techniques (manual, automated and with new software) to determine the optimal calibration frequency. The second stage, longer term, was like the pilot stage with the best calibration method tested over 10 weeks. The third test was a simple before-and-after calibration test, conducted to determine the effect of calibration. It was concluded that the calibration process is essential to maintain the reliability of the mats and it was decided that the systems in Wales should be calibrated every 2 months to provide a more consistent output. 相似文献
950.
This work aims to evaluate the changes in cerebrospinal fluid (CSF) hydrodynamics in patients diagnosed with communicating hydrocephalus. Besides, we establish the relationship between CSF flow dynamic parameters on the midbrain aqueduct and intracranial pressure (ICP). CSF hydrodynamics analysis was performed using Phase-Contrast Magnetic Resonance Imaging (PC‐MRI) techniques on the midbrain aqueduct of 41 patients diagnosed with communicating hydrocephalus and 22 healthy volunteers. The correlation between CSF average flow in the midbrain aqueduct and intracranial pressure measured by Lumbar Puncture (LP) was assessed in patients with hydrocephalus. Pearson correlation coefficient was used to establish the correction between the average CSF flow of midbrain aqueduct and ICP. CSF dynamic parameters of the midbrain aqueduct in hydrocephalus patients, including peak positive velocity (7.348 cm/s), average velocity (0.623 cm/s), average flow (50.799 mm3/s), and regions of interest (ROI) area (9.978 mm2) were significantly higher than in the healthy controls (p < 0.05). This was after adjusting the age, gender, heart rate, systolic blood pressure, diastolic blood pressure, and body mass index. However, only the peak negative velocity of the midbrain aqueduct did not significantly differ between the groups (p = 0.209). A positive correlation was noted between the average flow (AF) of the midbrain aqueducts and ICP in hydrocephalus patients (y (AF) = 0.386× (ICP)−33.738, r = 0.787, p < 0.05). Reference data of CSF flow dynamic parameters was obtained through the PC-MRI in middle-aged healthy volunteers and communicating hydrocephalus patients. Although the sample size was constrained, this study has significant contributions. For instance, a significant correlation was noted between the average CSF flow of the aqueduct and ICP. This therefore provides a reference for clinicians to monitor ICP in patients with hydrocephalus. 相似文献