过度训练的病理生理及康复 Ⅰ.大鼠过度训练模型的建立

实验表明,运用大鼠跑台运动,以心电图、体重、饮食量、精神状况、毛发脱落、尿蛋白、血清睾酮、皮质醇等为监测指标建立大鼠过度训练模型的方法是可行的。本文并首次模拟出大鼠运动性心律失常心电图。     

Assessment of Rhythm and Rate Control in Patients with Atrial Fibrillation

A recent series of randomized prospective clinical trials that compared rate control with rhythm control in patients with atrial fibrillation (AF) found no significant difference in primary outcome between the two strategies. However, these trials lacked clear criteria for defining "successful" rate or rhythm control. Various measures have been used to gauge the success of antiarrhythmic drug therapy, including time to first recurrence of AF, any AF recurrence, AF burden, and a reduction in symptoms. Determining the success of antiarrhythmic therapy can be relatively straightforward by using how patients feel during therapy as a key endpoint. Most patients are satisfied with a major reduction in symptomatic AF episodes and can live comfortably with occasional episodes of AF. For those who are bothered by even infrequent, brief AF episodes, a treatment regimen that eliminates nearly all AF recurrences is required, although often hard to achieve. Catheter ablation may be necessary to achieve a successful outcome in these patients. Suppression of AF in a patient at high risk of stroke does not, however, remove the need for concomitant warfarin therapy. The endpoints of ventricular rate control are not clear, and the recently published rhythm versus rate control trials lacked standard criteria for judging acceptable rate control. One relatively simple method is to try and achieve a 24-hour heart rate that mimics expected normal sinus rhythm. It is important to achieve good rate control to minimize symptoms and the risk of tachycardia-mediated cardiomyopathy.     

常用生理参数的测量原理

随着医学事业的发展,监护仪得到广泛的运用,就医用监护仪常用生理参数的工作原理简述如下。     

Can Electrocardiographic Criteria Predict Adverse Cardiac Events and Positive Cardiac Markers?

OBJECTIVES: To determine electrocardiogram (ECG) predictors of positive cardiac markers and short-term adverse cardiac events in an undifferentiated chest pain population presenting to emergency departments (EDs). The authors hypothesized that specific ECG findings, other than those previously identified in higher-risk populations, would be predictive of cardiac outcomes and positive cardiac markers. METHODS: This study used data from a prospectively collected, retrospectively analyzed Internet-based data registry of undifferentiated chest pain patients (i*trACS). Logistic regression modeling was performed to determine the ECG findings that were predictive of 1) positive cardiac markers and 2) short-term adverse cardiac events. RESULTS: ST-segment elevation (STE), ST-segment depression (STD), pathological Q-waves (PQW), and T-wave inversion were associated with increased odds of percutaneous coronary intervention or catheterization, myocardial infarction, or coronary artery bypass grafting. The odds of creatine kinase-MB (CK-MB) measuring positive were increased if STE, STD, or PQW were present [odds ratio (OR) 2.495, 2.582, and 1.295, respectively]. A right bundle branch block tended to decrease the odds of CK-MB measuring positive (OR 0.658). A similar pattern of results was observed for troponin I (OR 3.608 for STE, 3.72 for STD, 1.538 for PQW). Troponin T showed an increased odds of measuring positive if any of STE, STD, left bundle branch block, or T-wave inversion were evident (OR 2.313, 2.816, 1.80, and 1.449, respectively). CONCLUSIONS: Initial ECG criteria can be used to predict short-term cardiac outcomes and positive cardiac markers. These findings can be important aids in the risk-stratification and aggressive treatment regimens of chest pain patients presenting to EDs.     

基于多分辨率分析的心电图QRS波检测

从多分辨率分析出发，构造出一个用于心电图R波检测的滤波器，并在此滤波器的基础上提出了一种新的R波检测算法。本文详细论述了滤波器的构造方法和新的R波检测算法的原理及在实现中采用的一些策略，经MIT-BIH标准心律失常数据库验证，该算法对于各种干扰尤其是肌电干扰具有很强的抑制能力。算法实现简单，计算量小，在ECG信号的脱机和实时处理程序中均可使用。     

基于MATLAB胎儿心电实时显示

文章介绍了从母亲体中采集到的心电信号，利用MATLAB软件对采集到的心电信号进行准确的数据实时处理，分离出胎儿心电（ECG）信号，实验结果表明，这种方法有一定的实用性。     

Assessment of changes in 1-second forced expiratory volume in bronchial provocation testing

The question of whether functional residual capacity (FRC) falls in infants during active sleep has been clouded by studies using different subject groups and techniques for measurements of lung volume and determination of sleep state. Twenty healthy full-term infants within the first week of life participated in the present study. Neurophysiological and behavioral criteria were used to define sleep state, and measurements of FRC were made using a specially constructed closed-circuit helium dilution system. Regularity of respiration was recorded using magnetometers on the chest and a modified respirator monitor. Results showed that no significant changes in FRC occurred, related either to sleep state or to regularity of respiration. In addition, we failed to detect any differences in FRC between the sexes. Pediatr Pilmonol. 1989; 7:71–77 .