期刊文献+
共找到14,215篇文章
< 1 2 250 >
每页显示 20 50 100
HEART评分对急诊科急性胸痛患者30天心血管不良事件预测价值 被引量:27
1
作者 黄振华 詹红 +4 位作者 肖孝勇 叶子 蒋鹏 蔡锐彬 廖瑾莉 《实用医学杂志》 CAS 北大核心 2017年第14期2341-2344,共4页
目的评价HEART评分对急性胸痛患者30 d心血管不良事件(MACE)的预测价值。方法使用前瞻性观察研究的方法,收集2016年1-4月在我院急诊科就诊的急性胸痛患者,并对纳入的患者进行30 d心血管不良事件的随访。结果本研究纳入209例患者,平均(65... 目的评价HEART评分对急性胸痛患者30 d心血管不良事件(MACE)的预测价值。方法使用前瞻性观察研究的方法,收集2016年1-4月在我院急诊科就诊的急性胸痛患者,并对纳入的患者进行30 d心血管不良事件的随访。结果本研究纳入209例患者,平均(65.28±16.85)岁,男110例(52.63%),MACE组患者年龄、高血压、ACS比率、SpO_2、需要住院、HEART评分高于非MACE组,2组比较差异具有统计学意义(P<0.05);MACE组患者入院血压(收缩压、舒张压)低于非MACE组,2组比较差异具有统计学意义(P<0.05);30 d随访发生心血管不良事件概率为5.74%,HEART评分对30 d心血管不良事件的发生有良好的预测价值,ROC曲线下面积为0.908(95%CI 0.846~0.974),不同HEART评分危险分层30 d心血管不良事件概率分别为0~3分(0)、4~6分(2.5%)、7~10分(27%)。结论 HEART评分能简单、快速、准确的预测急性胸痛患者30 d内MACE,有效排除低危胸痛患者MACE,对急诊科快速病情评估和诊治过程起到非常重要的作用。 展开更多
关键词 heart评分 急性胸痛 急诊科 心血管不良事件
在线阅读 下载PDF
基于HEART评分预测心电图非ST段抬高的急性胸痛患者心脏不良事件的价值 被引量:18
2
作者 余洋 李博 +4 位作者 刘聚伟 刘杰 杨丽君 郝春艳 高丽杰 《实用医学杂志》 CAS 北大核心 2019年第14期2261-2265,共5页
目的验证HEART评分对心电图非ST段抬高的急性胸痛患者30 d主要不良心脏事件(MACE)的预测价值。方法采用前瞻性观察研究方法,连续入选2014年2月至2017年2月在解放军总医院第八医学中心急诊科就诊,心电图为非ST段抬高的急性胸痛患者1 550... 目的验证HEART评分对心电图非ST段抬高的急性胸痛患者30 d主要不良心脏事件(MACE)的预测价值。方法采用前瞻性观察研究方法,连续入选2014年2月至2017年2月在解放军总医院第八医学中心急诊科就诊,心电图为非ST段抬高的急性胸痛患者1 550例,平均年龄(52.3±12.1)岁,男778例(50.2%)。收集患者的基线临床资料,对每例患者进行HEART评分,基于HEART评分将患者分为3组:低危组(0~3分)775例(50.0%);中危组(4~6分)465例(30.0%);高危组(7~10分)310例(20.0%),中、高危患者收入院检查治疗,低危组患者在急诊室观察2 h后复查心电图和心肌肌钙蛋白I(cTnI),若无异常改变即可离院。对所有患者随访30 d,研究终点为就诊后30 d内MACE发生情况,采用多因素Logistic回归分析HEART评分对非ST段抬高的急性胸痛患者30 d内MACE的预测价值。结果3组患者比较,随着HEART评分增加,患者年龄、体质量指数(BMI)、心率(HR)、收缩压(SBP)、舒张压(DBP)升高,合并心血管病危险因素比例增高,动脉粥样硬化疾病病史的比例增高,差异均有统计学意义(P<0.05);低危组、中危组、高危组30 d内MACE发生率分别为[0.65%(5/775)、13.3(62/465)、55.16(171/310),χ^2=126.87,P<0.01];多因素Logistic回归分析结果显示HEART评分是总MACE的独立预测因子(OR=13.219,95%CI:6.817~24.745,P<0.01)。结论应用HEART评分能够简单、快速地评估心电图非ST段抬高的急性胸痛患者危险分层,准确预测急性胸痛患者30 d的MACE风险,有效识别低危患者。 展开更多
关键词 heart评分 急性胸痛 非ST段抬高 心脏不良事件
在线阅读 下载PDF
基于HEART方法的管制员调配飞行冲突的人为差错概率研究 被引量:15
3
作者 高扬 朱艳妮 《安全与环境工程》 CAS 北大核心 2013年第4期97-101,共5页
空中交通管制员的核心任务之一是调配飞行冲突,故有必要对管制员调配飞行冲突的可靠性进行分析与评估。本文首次将HEART方法应用于管制员调配飞行冲突的人为差错概率分析,并根据相关人因可靠性分析方法对HEART中的任务分类和差错诱发条... 空中交通管制员的核心任务之一是调配飞行冲突,故有必要对管制员调配飞行冲突的可靠性进行分析与评估。本文首次将HEART方法应用于管制员调配飞行冲突的人为差错概率分析,并根据相关人因可靠性分析方法对HEART中的任务分类和差错诱发条件进行了改进,从而提高了该方法在空中交通领域的适用性。改进后的HEART方法能对管制员调配飞行冲突的人为差错概率进行定量分析,并可发现起负面作用的差错诱发条件,可为管理部门有针对性地制定改进措施提供技术支持,对保障空中交通安全有序地运行具有重要的意义。 展开更多
关键词 空中交通管制员 调配飞行冲突 人因可靠性分析(HRA) 人为差错概率 heart方法
在线阅读 下载PDF
OpenSSL HeartBleed漏洞分析及检测技术研究 被引量:5
4
作者 强小辉 陈波 陈国凯 《计算机工程与应用》 CSCD 北大核心 2016年第9期88-95,101,共9页
HeartBleed漏洞是一个严重的安全漏洞。分析了OpenSSL中心跳机制的源代码,在代码层次总结了HeartBleed漏洞产生的原因。采用Python语言实现了漏洞检测脚本工具,通过发送心跳信息长度与长度字段不一致的心跳数据包,并根据响应数据包的类... HeartBleed漏洞是一个严重的安全漏洞。分析了OpenSSL中心跳机制的源代码,在代码层次总结了HeartBleed漏洞产生的原因。采用Python语言实现了漏洞检测脚本工具,通过发送心跳信息长度与长度字段不一致的心跳数据包,并根据响应数据包的类型和响应数据的长度,判断目标是否存在HeartBleed漏洞。针对应用OpenSSL的Web网站以及网络服务的服务器进行了检测实验。与已有检测工具的比较实验表明,实现的检测脚本工具检测范围广,检测时间快,正确率高,可以有效完成HeartBleed漏洞的检测工作。 展开更多
关键词 安全套接层协议(SSL) OPENSSL heartBleed漏洞 漏洞检测 软件安全开发
在线阅读 下载PDF
Computed tomography versus transthoracic echocardiography in the detection of complex congenial heart diseases in china:a meta-analysis
5
作者 畅智慧 LIN Kun +3 位作者 DU Xiao-li YIN Xiao-li LU Zhao 刘兆玉 《放射学实践》 2012年第11期1168-1173,共6页
Objective:To perform a meta-analysis to evaluate the diagnostic performance of computed tomography(CT) and transthoracic echocardiography(TTE) in complex congenital heart diseases(CHD) in China.Methods:MEDLINE,Cochran... Objective:To perform a meta-analysis to evaluate the diagnostic performance of computed tomography(CT) and transthoracic echocardiography(TTE) in complex congenital heart diseases(CHD) in China.Methods:MEDLINE,Cochrane library and China National Knowledge Infrastructure(CNKI) database from January 1966 to October 2010,were searched for initial studies in China.All the studies,published in English or Chinese,used TTE,CT,or both as diagnostic tests for CHD and reported the rate of true-positive,true-negative,false-positive and false-negative diagnoses of CHD from TTE and CT findings with the surgical results as the 'gold-standard'(15 studies,XX patients) were collected.The statistic software package,'Meta-Disc 1.4',was used to conduct data analysis.A covariate analysis was used to evaluate the influence of patient or study-related factors on sensitivity.Results:Pooled sensitivity for diagnosis of CHD were 95% [95% confidence interval(CI):94%~96%] for CT studies and 87%(95% CI:85%~88%) for TTE studies.The difference between the pooled sensitivity of CT and that of TTE was statistically significant(P<0.001).TTE had higher sensitivity [0.96(95% CI:0.94~0.97)] for cardiac malformation but lower sensitivity [0.78(95% CI:0.76~0.81)] for extracardiac malformation than CT.Conclusion:CT can provide added diagnostic information compared with TTE in patients with CHD in China,especially for patients suspected of extracardiac malformation. 展开更多
关键词 ECHOCARDIOGRAPHY Tomography X-ray computed heart Defects Congenital META-ANALYSIS
在线阅读 下载PDF
基于SHERPA和HEART的老年人车载信息系统界面设计研究 被引量:2
6
作者 林巧仪 朱丽萍 李永锋 《包装工程》 CAS 北大核心 2024年第18期44-52,共9页
目的改善老年驾驶员对车载信息系统界面的使用体验。方法提出基于SHERPA(系统人为错误减少与预测方法)和HEART(人误评估与减少技术)的老年人车载信息系统界面设计研究方法。首先,成立焦点小组对评估界面进行SHERPA定性分析,绘制车载信... 目的改善老年驾驶员对车载信息系统界面的使用体验。方法提出基于SHERPA(系统人为错误减少与预测方法)和HEART(人误评估与减少技术)的老年人车载信息系统界面设计研究方法。首先,成立焦点小组对评估界面进行SHERPA定性分析,绘制车载信息系统界面层次任务分析图,通过错误分类表定义错误类型;其次,运用HEART定量分析错误类型,设定差错诱发条件,确定各条件的影响评估比例,从而计算人误概率;最后,在此基础上,分析差错诱发条件,归纳差错发生原因,根据差错纠正措施进行设计改良,对改良界面进行结果验证。结论该方法可以有效发现与老年人车载信息系统界面显著相关的差错诱发条件,既可帮助设计师找到交互设计改良的重点,也可减少老年驾驶员对车载信息系统界面的误操作情况。 展开更多
关键词 交互设计 SHERPA heart 车载信息系统 老年人
在线阅读 下载PDF
HEART-50重复频率高功率脉冲驱动源研究 被引量:2
7
作者 李嵩 杨汉武 +6 位作者 樊玉伟 张自成 高景明 荀涛 樊鹏 陈冬群 钱宝良 《强激光与粒子束》 CAS CSCD 北大核心 2022年第9期116-120,共5页
通过理论计算、数值仿真和实验验证的方法,研究了一台峰值功率数十GW、重复频率5 Hz的重复频率高功率脉冲驱动源,命名为“HEART-50”。该脉冲驱动源由充电电源、初级开关、脉冲形成线、主开关、阻抗变换线,以及假负载构成。首先介绍了HE... 通过理论计算、数值仿真和实验验证的方法,研究了一台峰值功率数十GW、重复频率5 Hz的重复频率高功率脉冲驱动源,命名为“HEART-50”。该脉冲驱动源由充电电源、初级开关、脉冲形成线、主开关、阻抗变换线,以及假负载构成。首先介绍了HEART-50重复频率高功率脉冲驱动源整体设计思路;其次,对基于混合液体介质的高功率脉冲形成线和气体介质主开关进行了数值分析,并对其全电路工作能力进行了仿真分析;最后,对研制的HEART-50重复频率高功率脉冲驱动源进行了实验验证。结果表明,脉冲驱动源能够输出峰值电压520 kV,脉冲宽度约90 ns,脉冲上升沿小于25 ns,重复频率5 Hz的准方波电脉冲,峰值电功率约为25.3 GW,且具有较好的运行稳定性。 展开更多
关键词 脉冲功率技术 高功率 重复频率 heart-50
在线阅读 下载PDF
CICARE联合HEART沟通模式在责任制护理中的应用 被引量:54
8
作者 肖馨爽 肖欢 +1 位作者 谭杰 汤曼力 《护理学杂志》 CSCD 北大核心 2019年第23期69-71,共3页
目的探讨CICARE联合HEART沟通模式在创伤外科患者责任制护理中的应用效果。方法按时间段将280例多发伤住院患者分为对照组143例,观察组137例。对照组实施常规沟通方式,观察组采取CICARE联合HEART沟通模式,比较两组患者健康教育掌握程度... 目的探讨CICARE联合HEART沟通模式在创伤外科患者责任制护理中的应用效果。方法按时间段将280例多发伤住院患者分为对照组143例,观察组137例。对照组实施常规沟通方式,观察组采取CICARE联合HEART沟通模式,比较两组患者健康教育掌握程度,以及对责任制护理的满意度。结果实施后,观察组患者健康教育掌握程度、护理满意度显著高于对照组(均P<0.01)。结论CICARE联合HEART沟通模式应用于创伤外科护理中,能获得较好的沟通效果,有效提升护患关系及对护理服务的满意度。 展开更多
关键词 CICARE沟通 heart沟通 护理 沟通 护患沟通 护患关系 患者满意度
在线阅读 下载PDF
HEART风险评分在有冠心病的急性胸痛人群中的应用研究 被引量:13
9
作者 马春朋 刘晓丽 +6 位作者 蔡丽丽 朱爱红 董雪飞 马春明 马利祥 王庆胜 聂绍平 《实用医学杂志》 CAS 北大核心 2021年第2期215-219,共5页
目的研究HEART风险评分在有冠心病的急性胸痛人群中的应用价值。方法利用已有数据库进行回顾性分析。连续入选有冠心病病史的急性胸痛人群,计算HEART风险评分。研究终点为3个月时主要不良心脏事件。结果研究共入选377例急性胸痛患者,其... 目的研究HEART风险评分在有冠心病的急性胸痛人群中的应用价值。方法利用已有数据库进行回顾性分析。连续入选有冠心病病史的急性胸痛人群,计算HEART风险评分。研究终点为3个月时主要不良心脏事件。结果研究共入选377例急性胸痛患者,其中186例患者发生主要不良心脏事件。HEART风险评分的受试者操作特征曲线(ROC)下面积为0.73(95%CI:0.68~0.78)。入选患者分为3组:低危组(评分2~3分),中危组(评分4~5分)和高危组(评分6~10分),主要不良心脏事件发生率分别为8.3%(1/12),38.3%(72/188)和63.8%(113/177),各组间差异有统计学意义(P<0.001)。根据不同的危险分层,实施不同的分诊策略。结论HEART风险评分可以用于有冠心病的急性胸痛人群的分诊。 展开更多
关键词 胸痛 急诊 冠心病 风险评分 高敏肌钙蛋白I
在线阅读 下载PDF
Transgelin as a potential target in the reversibility of pulmonary arterial hypertension second to congenital heart disease 被引量:9
10
作者 Li Huang Li Li +6 位作者 Tao Yang Wen Li Li Song Xianmin Meng Qing Gu Changming Xiong Jianguo He 《中国循环杂志》 CSCD 北大核心 2018年第S01期165-166,共2页
Background The reversibility of pulmonary arterial hypertension(PAH)in congenital heart disease(CHD)is of great importance for the operability of CHD.Proteomics analysis found that transgelin was significantly upregul... Background The reversibility of pulmonary arterial hypertension(PAH)in congenital heart disease(CHD)is of great importance for the operability of CHD.Proteomics analysis found that transgelin was significantly upregulated in the lung tissue of CHD-PAH patients,especially in the irreversible group.However,how exactly it participated in CHD-PAH development is unknown. 展开更多
关键词 pulmonary arterial hypertension CONGENITAL heart disease CHD-PAH
在线阅读 下载PDF
HEART评分联合白细胞介素6、D-二聚体、抗心磷脂抗体对急诊胸痛患者30 d内主要不良心血管事件的预测价值 被引量:8
11
作者 李庆 方凯 +2 位作者 廖中华 尧鹏 祝衡 《郑州大学学报(医学版)》 CAS 北大核心 2023年第2期246-250,共5页
目的:研究HEART评分联合白细胞介素6(IL-6)、D-二聚体(D-D)和抗心磷脂抗体(ACA)对急诊胸痛患者30 d内主要不良心血管事件(MACE)的预测价值。方法:选取149例急诊胸痛患者进行HEART评分,同时检测血清IL-6、D-D和ACA水平,然后随访30 d内MAC... 目的:研究HEART评分联合白细胞介素6(IL-6)、D-二聚体(D-D)和抗心磷脂抗体(ACA)对急诊胸痛患者30 d内主要不良心血管事件(MACE)的预测价值。方法:选取149例急诊胸痛患者进行HEART评分,同时检测血清IL-6、D-D和ACA水平,然后随访30 d内MACE发生情况,分析HEART评分联合IL-6、D-D和ACA对急诊胸痛患者30 d内MACE的预测价值。结果:149例中,30 d内发生MACE 46例(30.87%)。MACE组HEART评分及血清IL-6、D-D和ACA-IgG水平高于未发生MACE组(P<0.05)。ROC曲线分析结果显示HEART评分预测急诊胸痛患者30 d内MACE的AUC(95%CI)为0.912(0.865~0.959),以HEART评分>5分、IL-6>147.55 ng/L、D-D>226.54μg/L和ACA-IgG>5.23 U/mL为单指标阳性,以HEART评分阳性且IL-6、D-D和ACA中任意一项阳性为阳性进行联合诊断,结果显示敏感度为93.48%,特异度为62.14%,阳性预测值为52.44%,阴性预测值为95.52%。结论:HEART评分联合IL-6、D-D和ACA预测急诊胸痛患者30 d内MACE准确率较高。 展开更多
关键词 急诊胸痛 主要不良心血管事件 heart评分 白细胞介素6 D-二聚体 抗心磷脂抗体
在线阅读 下载PDF
Biomechanical Manifestations of Diastolic and Systolic Function in Rats with Heart Failure with Preserved Ejection Fraction 被引量:1
12
作者 Zhongjie Yin Wenchang Tan 《医用生物力学》 EI CAS CSCD 北大核心 2019年第A01期77-77,共1页
Objective Heart failure(HF)is divided into two types:Heart failure with reduced ejection fraction(HFrEF)and heart failure with preserved ejection fraction(HFpEF).The latter always results in diastolic dysfunction,char... Objective Heart failure(HF)is divided into two types:Heart failure with reduced ejection fraction(HFrEF)and heart failure with preserved ejection fraction(HFpEF).The latter always results in diastolic dysfunction,characterized by changes in mechanical properties.The objective of this study is to build a finite element(FE)model of HFpEF and analyze diastolic and systolic function in rats.Methods Ten Dahl salt-sensitive rats were fed either a low-salt(LS)(n=5)or highsalt(HS)(n=5)diet beginning at 7 weeks of age and scanned by ultrasonic machine at 14 weeks of age.A non-linear FE model of the left ventricle(LV)was built from cardiac echo images at end-diastole and passive material properties of the LV were prescribed using Fung’s transversely isotropic constitutive law.Fiber angles of the endocardium and epicardium were prescribed as 53°°and-52°,respectively,with respect to the circumferential direction and varied linearly through the LV wall.The method developed by Krishnamurthywas used to determine the unloaded geometry to estimate the Fung passive material parameters.LV end-diastolic pressure(EDP)was determined from the measured pressure waves and applied to the endocardium at the unloaded geometry to simulate passive filling.Active material properties of the LV were prescribed using Guccione’s time-varying elastance model and maximum isometric tension was scaled to match the measured peak systolic pressure.The finite element model was then coupled to the Windkessel model,whose parameters were adjusted to the measured hemodynamics.Results Measured LVEDPs of LS and HS rats were 4.9±3.4 mmHg and 13.2±5.4 mmHg(P-0.030 8),respectively.End-diastolic Cauchy stress along the fiber direction for LS rats was significantly lower than for HS rats(0.91±0.60 kPa vs 3.00±0.63 kPa,P=0.001 4)and there was a similar trend in end-diastolic Green Strain along the fiber direction(0.058±0.003 vs 0.072±0.010,P=0.012 8,Figure 1b),as well.There was no distinctive difference between end-systolic Cauchy stress along the fiber direction for LS rats and HS rats(17.2±4.3 kPa vs 17.2±5.5 kPa,P=0.991 9)but end-systolic Green Strain along the fiber direction for LS rats was significantly higher than for HS rats(-0. 108±0.017 vs-0.065±0.024,negative sign represents direction).Conclusions For rats with HFpEF,it is the elevated LVEDP that induces the increase in end-diastolic stress and strain,thereby leading to diastolic dysfunction.Because of the preserved ejection fraction,HFpEF has less effect on systolic function. 展开更多
关键词 BIOMECHANICAL MANIFESTATIONS heart Failure PRESERVED EJECTION Fraction CAUCHY
在线阅读 下载PDF
HEART评分在急性冠状动脉综合征相关性胸痛患者中的应用进展 被引量:3
13
作者 吴德喜 宋兴隆 +1 位作者 闫浩东 郭文怡 《中国心血管杂志》 2022年第6期606-610,共5页
快速识别非ST段抬高型急性冠状动脉综合征(NSTE-ACS)患者是广大临床医生面临的重大挑战。HEART评分可用于NSTE-ACS相关性胸痛患者的危险分层,能够减少低危患者留院时间和行冠状动脉造影或冠状动脉CT血管成像的次数,促进更合理的资源分... 快速识别非ST段抬高型急性冠状动脉综合征(NSTE-ACS)患者是广大临床医生面临的重大挑战。HEART评分可用于NSTE-ACS相关性胸痛患者的危险分层,能够减少低危患者留院时间和行冠状动脉造影或冠状动脉CT血管成像的次数,促进更合理的资源分配。本文就近年来HEART评分在评估ACS相关性胸痛的研究进展进行综述。 展开更多
关键词 急性冠状动脉综合征 heart评分 胸痛
在线阅读 下载PDF
Comparing the rhythm and frequency of heart,breathing and knee movement in Tai Chi Chuan
14
作者 魏珊珊 刘宇 李立 《医用生物力学》 EI CAS CSCD 2009年第S1期150-151,共2页
Background:The basic exercise involved in TCC is a series of individual movements that are linked together in a continuous manner and that flow smoothly from one movement to another.Deep breathing and mental concentra... Background:The basic exercise involved in TCC is a series of individual movements that are linked together in a continuous manner and that flow smoothly from one movement to another.Deep breathing and mental concentration are also required to achieve harmony 展开更多
关键词 Comparing the rhythm and frequency of heart breathing and knee movement in Tai Chi Chuan
在线阅读 下载PDF
Establishment and improvement of model of vascularized heart-thymus composite transplantation in rats 被引量:2
15
作者 XIONG Hai-bo XIA Sui-sheng +2 位作者 WEN Hao HUANG Zu-fa YE Qi-fa 《Journal of Central South University of Technology》 2005年第z1期347-349,共3页
Objective To establish and improve the model of heart-thymus composite transplantation.Methods Vascularized both lobes of the thymus is transplanted heterotopically with the heart as a composite graft in rats.This tec... Objective To establish and improve the model of heart-thymus composite transplantation.Methods Vascularized both lobes of the thymus is transplanted heterotopically with the heart as a composite graft in rats.This technique was developed and assessed,and viability of the grafts was evaluated histologically.Results Donor operation costed 38.5±3.52 min,vascular anastomosis costed 25.0±3.28 min,operating successful rate was 90%,acute rejection was observed in SD-Wistar group,viable thymus with normal microarchitecture was maintained in Wistar-Wistar group.Conclusions The improved novel technique for combined heart-thymus transplantation is a valuable method for study of the role of thymus in transplantation immunity. 展开更多
关键词 heart THYMUS composite transplantation rat animal model transplantation immunity
在线阅读 下载PDF
汉语“心”和英语“heart”的语义范畴转移比较 被引量:1
16
作者 谢之君 史婷婷 《山东外语教学》 2007年第4期30-35,共6页
本文通过汉语“心”和英语“heart”的语义范畴的转移比较,揭示不同语言系统中人类相似的认知过程:人们通过具体的身体经验的隐喻化去理解抽象的情感、心理、思维等,语言原始形态在不断理解和认识世界中产生新的语义。
关键词 隐喻 范畴转移 认知
在线阅读 下载PDF
Effect of Changing Heart Rate on the Ocular Pulse and Optic Nerve Head Deformations
17
作者 Yuejiao Jin Xiaofei Wang +4 位作者 Sylvi Febriana Rachmawati Irnadiastputri Rosmin Elsa Mohan Tin Aung Leopold Schmetterer Michal JAGirard 《医用生物力学》 EI CAS CSCD 北大核心 2019年第A01期183-184,共2页
Objective To study the effect of changing heart rate on the ocular pulse and optic nerve head deformations with a viscoelastic lamina cribrosa.Methods An FE model of a healthy eye was reconstructed.The choroid was bip... Objective To study the effect of changing heart rate on the ocular pulse and optic nerve head deformations with a viscoelastic lamina cribrosa.Methods An FE model of a healthy eye was reconstructed.The choroid was biphasic and consisted of a solid phase(connective tissues)and a fluid phase(blood).The LC was viscoelastic as characterized by a stress-relaxation test.We applied arterial pressures at 18 entry sites(posterior ciliary arteries)and venous pressures at 4 exit sites(vortex veins).The heart rate was varied from 60 bpm to 120 bpm(increment:20 bpm).We reported the ocular pulse amplitude(OPA),pulse volume,optic nerve head(ONH)deformations and the dynamic modulus of the LC at different heart rates.Results With an increasing heart rate,the OPA decreased by 0.04 mmHg for every 10 bpm increase.The pulse volume also exhibited a linear relationship with heart rate,and decreased by 0.13 L.In addition,the storage modulus and the loss modulus of the LC center increased by 0.014 MPa and 0.04 MPa,respectively for every 10 pm increase in heart rate.Conclusions Our model predicted that the OPA,the pulse volume the ONH deformation decreased at a faster heartrate.We also found that the viscoelastic LC became stiffer with an increasing heart rate.Further studies are required to explore the potential links with the vascular dysregulation and axonal loss in glaucoma. 展开更多
关键词 heart Rate OCULAR PULSE OPTIC NERVE Head Deformations
在线阅读 下载PDF
Detection of Mitral Valve Diseases by Bicoherence Analysis of Heart Sound Signals
18
作者 O.Akgun H.S.Varol 《光谱学与光谱分析》 SCIE EI CAS CSCD 北大核心 2017年第10期3270-3273,共4页
The analysis of 10 normal and 51 mitral valve pathology making a total of 61 heart sound signals that were obtained with Littmann 4100 Digital Stethoscope were conducted in this study.Following the recorded sound sign... The analysis of 10 normal and 51 mitral valve pathology making a total of 61 heart sound signals that were obtained with Littmann 4100 Digital Stethoscope were conducted in this study.Following the recorded sound signals were denoised by using wavelet filters,the signals were applied bicoherence analysis that is an high order spectral analysis method.It has been demonstrated that varieties of mitral valve pathology could be determined by three-dimensional surfaces of bicoherence and maximum bicoherence values. 展开更多
关键词 Mitral valve heart sound signals Bicoherence analysis
在线阅读 下载PDF
Meta-analysis of serum copper and heart failure
19
作者 An-qi ZHANG Li-la ZHU Xi-yue ZHANG 《中国药理学与毒理学杂志》 CAS CSCD 北大核心 2017年第10期1028-1028,共1页
OBJECTIVE The purpose of this study is to clarify the association between Cu levels and heart failure(HF)using a meta-analysis approach.METHODS We searched articles in the Pub Med,EMbase,CNKI,Wanfang,VIP and CBM Datab... OBJECTIVE The purpose of this study is to clarify the association between Cu levels and heart failure(HF)using a meta-analysis approach.METHODS We searched articles in the Pub Med,EMbase,CNKI,Wanfang,VIP and CBM Database published as of August 2016.The case control study on the relationship between serum copper levels and HF were collected and read and extracted by two independent researchers.A Meta analysis was conducted using Stata 12.0 software.RESULTS A total of twenty-one eligible articles,including 893 HF and 654 control subjects,were enrolled.The Meta analysis showed that serum copper levels in HF were higher than control group[SMD=0.881,95%CI:(0.487,1.264),Z=4.5,P<0.001].The sensitivity analysis indicated that the results were reliable.Begg′s tests did not find the existence of publication bias.CONCLUSION This metaanalysis indicates that there is a significant association between high Cu serum level and HF. 展开更多
关键词 heart failure serum cu meta analysis
在线阅读 下载PDF
Study on Large Power Tractor Driver's Heart Rate and Fatigue in Sowing Work
20
作者 KONG Degang ZHAO Yongchao +2 位作者 ZHU Zhenying ZHANG Shuai ZHU Lei 《Journal of Northeast Agricultural University(English Edition)》 CAS 2008年第2期48-53,共6页
In order to reduce the driving fatigue in sowing work, this paper based on heart rate (HR) as the main indicator to survey, tested and analyzed the fatigue condition of the drivers of three imported tractors and one... In order to reduce the driving fatigue in sowing work, this paper based on heart rate (HR) as the main indicator to survey, tested and analyzed the fatigue condition of the drivers of three imported tractors and one domestic tractor in sowing work. The results showed that when driving the imported tractors in sowing work, the HR increasing rate was 10.4%-14.3%, labor intensity belonged to the light level; when driving domestic tractor in sowing work, the HR increasing rate was 23.4%-33.0%, it was remarkably bigger than that of driving imported tractors (P〈0.05), labor intensity belonged to the middle level. The main effects on driving fatigue included the control methods, tractors' cab environment, processing time, operating content, and so on. Finally, we proposed the concrete measures and suggestions to reduce driving fatigue and improve drivers' work condition. 展开更多
关键词 large power tractor sowing work driving fatigue heart rate labor intensity
在线阅读 下载PDF
上一页 1 2 250 下一页 到第
使用帮助 返回顶部