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101.
102.
Objective. Skeletal muscle perfusion during walking relies on complex interactions between cardiac activity and vascular control mechanisms, why cardiac dysfunction may contribute to intermittent claudication (IC) symptoms. The study aims were to describe cardiac function at rest and during stress in consecutive IC patients, to explore the relations between cardiac function parameters and treadmill performance, and to test the hypothesis that clinically silent myocardial ischemia during stress may contribute to IC limb symptomatology. Design. Patients with mild to severe IC (n?=?111, mean age 67 y, 52% females, mean treadmill distance 195 m) underwent standard echocardiography, dobutamine stress echocardiography (SE) and treadmill testing. The patient cohort was separated in two groups based on treadmill performance (HIGH and LOW performance). Results. Ten patients (9%) had regional wall motion abnormalities of which three had left ventricular ejection fraction <50% at standard echocardiography. A majority had lower than expected systolic- and diastolic ventricular volumes. LOW performers had smaller diastolic left ventricular volumes and lower global peak systolic velocity during dobutamine stress. No patient demonstrated significant cardiac dysfunction during dobutamine provocation that was not also evident at standard echocardiography. Conclusions. Most IC patients were without signs of ischemic heart disease or cardiac failure. The majority had small left ventricular volumes. The hypothesis that clinically silent myocardial ischemia impairing left ventricular function during stress may contribute to IC limb symptomatology was not supported.

Trial registration: ClinicalTrials.gov identifier: NCT01219842.  相似文献   
103.
金哲君  王雪  瞿春华 《西部医学》2019,31(12):1837-1840
目的 探讨手术烟雾对生理功能的危害性及采取防护措施的必要性。 方法 采用60只SD大鼠,随机分为空白组、烟雾组及干预组三组,每组20只。空白组不接受烟雾刺激,无任何防护;烟雾组和干预组大鼠在烟雾环境中安置30min;干预组大鼠提前接受预防措施。连续两周后检测手术烟雾环境中大鼠生理、生化指标及预防措施的有效性。 结果 使用电刀3min后,空气质量受到严重污染,并且随电刀使用时间增加而持续下降;连续两周后烟雾组大鼠心功能、血流动力学、呼吸功能受到明显损害,血清炎性因子IL-6、IL-8和TNF α浓度明显增加;而干预组大鼠生理功能受到明显保护,炎性因子浓度降低。在两周实验期内,手术烟雾对肝肾功能无明显影响。结论 手术烟雾会引起明显的生理功能损害,采取防护措施能起到良好的保护作用。  相似文献   
104.
糖尿病心肌病(Diabetic Cardiomyopathy,DC)的进展会导致左心室功能减低,因此,早期正确评估左心室功能对糖尿病心肌病患者的治疗和预后有着重要的意义。由于左心室解剖结构的复杂性,常规超声技术通常很难准确的评估左心室功能的变化,三维斑点追踪技术(three-dimensional speckle tracking imaging,3D-STI)是在实时3D超声和斑点追踪技术(STI)基础上发展起来的一项新技术,其对心脏功能的评估不受整个心脏运动方向和运动幅度的限制,能够直观的对心肌各个方向的运动进行追踪。本文首先论述3D-STI 在左心室功能评价中的可行性,再对其在DC左心室功能评价中的研究展开综述。  相似文献   
105.
《Clinical neurophysiology》2019,130(5):727-738
ObjectiveFunctional processes in the brain are segregated in both the spatial and spectral domain. Motivated by findings reported at the cortical level in healthy participants we test the hypothesis in the basal ganglia of Parkinson’s disease patients that lower frequency beta band activity relates to motor circuits associated with the upper limb and higher beta frequencies with lower limb movements.MethodsWe recorded local field potentials (LFPs) from the subthalamic nucleus using segmented “directional” DBS leads, during which patients performed repetitive upper and lower limb movements. Movement-related spectral changes in the beta and gamma frequency-ranges and their spatial distributions were compared between limbs.ResultsWe found that the beta desynchronization during leg movements is characterised by a strikingly greater involvement of higher beta frequencies (24–31 Hz), regardless of whether this was contralateral or ipsilateral to the limb moved. The spatial distribution of limb-specific movement-related changes was evident at higher gamma frequencies.ConclusionLimb processing in the basal ganglia is differentially organised in the spectral and spatial domain and can be captured by directional DBS leads.SignificanceThese findings may help to refine the use of the subthalamic LFPs as a control signal for adaptive DBS and neuroprosthetic devices.  相似文献   
106.
107.
ObjectiveValidation of linking coefficients to transform Pediatric Spinal Cord Injury Activity Measure (PEDI-SCI/AM) scores to adult Spinal Cord Injury-Functional Index (SCI-FI) scores.DesignThis cross-sectional study administered PEDI-SCI/AM and SCI-FI computerized adaptive tests (CATs) and short forms (SFs) to children with SCI and parents or caregivers.SettingHospitals, university, and rehabilitation institute.ParticipantsAbout 107 children with SCI and 96 parent or caregivers.InterventionsNot applicable.Main Outcome MeasuresLinking coefficients estimated SCI-FI (est-SCI-FI) scores from PEDI-SCI/AM scores for matched domains. Correlations between est-SCI-FI and actual SCI-FI scores were calculated. If correlations exceeded the criterion linking (0.866), the following analyses to compare est-SCI-FI and actual SCI-FI scores were conducted: paired t tests, intraclass correlation coefficients (ICCs 3, 1), percent of cases with absolute score differences at different thresholds.ResultsTwo matched domains, PEDI-SCI/AM Daily Routine/SCI-FI Self-Care and PEDI-SCI/AM General Mobility/SCI-FI Basic Mobility, met the linking criterion for both respondent-types (parent and child) and administration modes (CAT and SF). PEDI-SCI/AM Daily Routine and SCI-FI Fine Motor Function did not meet linking criterion for respondent type or mode. The linking criterion was met for wheelchair domains (child SF and CAT) and ambulation domains (child SF only). Significant differences between est-SCI-FI and actual SCI-FI scores were noted for all matched domains except Daily Routine/Self-Care (child SF only; parent SF and CAT). ICC values showed excellent agreement (range=0.75-0.89). Absolute differences between est-SCI-FI and actual SCI-FI scores were less than 1 standard deviation (except wheelchair CAT child).ConclusionsLinking coefficients applied to PEDI-SCI/AM scores can provide valid SCI-FI estimates that vary by domain, mode, and respondent type.  相似文献   
108.
Introduction: Neuropsychological assessment of cognitive change over time is often conducted in clinical settings, but whether neuropsychological change scores are influenced by physical health has, as far as we know, not been examined previously.

Method: In a sample of 153 older Swedish adults (age range, 72–86 years), we evaluated the influence of common age-related diseases, terminal decline pathology, age, education, and gender, to provide (a) preliminary test-specific regression weights and 90% confidence intervals to assess significant change in performance after five years on tests of visual scanning, mental shifting, visual spatial ability, memory, reaction time, and selective attention, and (b) normative data for the Useful Field of View test (UFOV) from a single testing occasion.

Results: Multiple regression analyses showed that test–retest changes were affected by physical health for mental shifting, visual spatial ability, memory, and reaction time, by age for mental shifting and visual reaction time, by education for visual spatial ability, and by Age × Education for auditory reaction time. Gender did not affect any of the change scores. The overall average of variance explained was 2.5%: up to 8.1% for physical health, 4.4% for age, and 3.6% for education. The UFOV scores were mostly influenced by age, but also by physical health and education.

Conclusions: The findings indicate that considering the influence of health on normative change scores in old age in addition to demographic factors leads to more accurate predictions of whether true change has occurred.  相似文献   

109.
随着早期胃癌的诊断率不断提高,其治疗手段的多样性和复杂性不断增加,包括胃癌治疗已经进入由内外科医师共同参与的多学科团队诊疗的时代。日本《胃癌治疗指南》是在近20年来日本胃癌流行病学变化趋势的背景下,基于日本国内和其他重要国际性临床试验的循证医学依据,由内科、外科和病理科医师共同组成的委员会负责编写和审核,每3~6年更新,至今已有5版,也是目前国际上最为权威的胃癌诊疗规范化、标准化的指导性文件。就早期胃癌而言,包括内镜治疗的变化、缩小手术的演变、腹腔镜手术的广泛应用和保留功能理念的推广,其治疗策略的演变充分体现了日本学者追求从肿瘤根治到微创功能保留,从长期生存的需求到更好生活质量的提高,贯彻了早期胃癌精准治疗的理念和思路。  相似文献   
110.
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