CT自适应心率变速扫描研究

针对心脏运动导致CT图像的模糊,提出了自适应心率的CT变速扫描方法.该方法可根据心率和所需要的时间可分辨率自适应选择最优的扫描拔,获得理想的投影数据.为了验证该模型,通过分段线性和非线性变形模型仿真心脏运动,利用滤波反投影重建算法进行了心脏图像重建.重建结果表明:根据心率选择合适的扫描速度可得到理想的投影数据,有效地提高了心脏图像质量,从而为CT心脏成像提供新的模式.     

健身气功·八段锦对老年人心肺功能影响

本研究观察经6个月健身气功·八段锦锻炼后对老年人心肺功能的影响．随机选取大连市沙河口区40名健康、无锻炼习惯的退休职工为实验对象,并随机分为实验组和对照组．验组在教师的指导下进行6个月、每天一次的健身气功“八段锦”锻炼．结果显示,与对照组比较,实验组肺活量及肺活量指数显著升高（P〈0．01）;LPET／LVET及平均动脉压明显下降（P〈0．05及P〈0．01）;CO、SV及台阶实验指数显著升高（P〈0．05及P〈0．01）．结果显示,6个月健身气功“八段锦”锻炼对老年人心肺功能的改善具有良好的促进作用．     

右腋下小切口在心脏瓣膜手术中的应用

腋下小切口心脏瓣膜手术属高难度微创心脏手术,我院自2001年11月-2002年5月,完成此类手术50例.手术切口自右腋下第3肋(间)至第5肋(间),长约7～9cm,经肋间进胸,建立体外循环.经右侧房间沟切口进入左心房,视瓣膜病变情况,选用二尖瓣置换术或二尖瓣成型术(多数在心脏跳动下完成).可经第4肋间进胸,经右心房房间隔切口置换二尖瓣,同时行三尖瓣DeVega环缩.行常规主动脉根部切口法行主动脉瓣替换.50例病人均顺利完成手术,主动脉阻断时间28～126min,平均(68.8±12.7)min,体外循环57～180min,平均(89.3±18.7)min.术后胸腔引流50～680mL,平均(230.5±107.3)mL,手术用血量0～600mL,平均(146.5±173.0)mL,38例病人未输库血.术后心功能明显改善,住院时间7～15d,平均(9.8±1.4)d,全组无死亡,无神经系统症状及感染等并发症发生.说明该手术技术安全、可靠,适用于绝大多数诊断明确的各类心脏瓣膜病变病人的外科治疗.     

Cardiac nonrigid motion analysis from image sequences

Noninvasive estimation of the soft tissue kinematics properties from medical image sequences has many important clinical and physiological implications, such as the diagnosis of heart diseases and the understanding of cardiac mechanics. In this paper, we present a biomechanics based strategy, framed as a priori constraints for the ill-posed motion recovery problems, to realize estimation of the cardiac motion and deformation parameters. By constructing the heart dynamics system equations from biomechanics principles, we use the finite element method to generate smooth estimates of heart kinematics throughout the cardiac cycle. We present the application of the strategy to the estimation of displacements and strains from in vivo left ventricular magnetic resonance image sequence.     

心肌细胞原代培养系统的建立及比率荧光技术对细胞内游离钙离子浓度的测定

以Fura-2/AM为指示剂,应用比率荧光测试技术,分别测定心肌细胞和B16细胞单个细胞 内游离钙离子浓度的变化.通过实验,建立了新生大鼠心肌细胞的原代培养系统,并将其应用于 [Ca2 ]i的比率荧光测量.结果显示,心肌细胞在滴加了NE之后,相对荧光强度有明显变化,肯定 了测试系统的有效性,并进一步筛选出适于B16细胞比率荧光测量[Ca2 ]i的各项参数.     

心磁和心电信号的混沌时间序列分析

计算了一组心磁和心电检测信号的关联维数和最大李亚普诺夫(Lyapunov)指数.心磁和心电信号的关联维数分别在2.28±0.27和1.12±0.13范围内,最大Lyapunov指数分别在0.68±0.12和0.32±0.04范围内.对其它4组数据中心测点的计算结果也说明心磁和心电信号具有混沌特性.此外,结果显示心磁边缘测点的混沌吸引子与中心部分有明显差别,可用于分析信号的有效检测范围.     

心脏瓣膜置换术后妊娠的处理（附8例）

目的：探讨心脏瓣膜置换术后妊娠的临床情况及处理。方法：分析经治的8例心脏瓣膜置换术后妊娠患者的临床表现、处理及结局。结果：8例心脏瓣膜置换术后妊娠患者经过合理抗凝,适时剖宫产分娩,母婴平安出院。结论：对心脏瓣膜置换术后妊娠患者应予重视,合理抗凝、密切监护,以保证患者在孕期和分娩期的安全。     

The performance of the octopus circulatory system: A triumph of engineering over design

Summary Despite the very considerable difficulties presented by the basic molluscan anatomy and the possession of a blood pigment with an oxygen carrying capacity that never exceeds 4.5 vols%, the cephalopod circulatory system contrives to deliver oxygen at a rate fully comparable with that of an active fish. This is achieved by adding accessory pumps to push blood through the gills, by a multiplicity of pulsatile veins and by raising the systemic blood pressure considerably above the levels found in other molluscs. Detailed control of blood distribution is a necessity in a system where the peripheral resistences may be expected to change dramatically when the animal starts to move and large parts of the central nervous system are apparently dedicated to this task. In this account we have reviewed blood pressure and flow at rest and in exercise. We have further examined the evidence which indicates how the animals modulate the cardiac output, drawing attention to the very different response found in cephalopods and the higher vertebrates.     

Regulations of thyroid hormone on cardiac protein kinase C signal pathway in vitro

The experiments were conducted to assess the influences of thyroid hormone on cardiac protein kinase C(PKC) signal pathway with cultured cardiac myocytes and fibroblasts as the models. Cells were pretreated with 1% newborn calf serum (NCS) or angiotensin II (Ang II), and then following by a triiodothyronine (T3) treatment. The PKC activity, PKC_α and PKC_ε expressions were analyzed and compared. In 1% NCS pretreatment, T3 could inhibit PKC activity and PKC_ε expression in cardiac myocytes. The AngII pretreatment led to an increase of PKC activity and PKC_ε expression in cardiac myocytes, and an increase of PKC activity in cardiac fibroblasts. Following by T3 treatment, the increased PKC activity and PKC_ε expression in cardiac myocytes were markedly decreased. In conclusion, whether in 1% NCS or in Ang II pretreatment, T3 could inhibit PKC activity and PKC_ε expression in cardiac myocytes. Foundation item: Supported by the Natural Science Foundation of Hubei Province (98091) Biography: WANG Bao-hua (1974-), female, Ph. D, research direction: cardiovascular pathophysiology.     

过度训练对心肌组织影响的研究进展

以过度训练对大鼠心肌组织损伤的研究进展为例,说明过度训练是一种常见的运动性病症,是训练与恢复、运动和运动能力、应激和耐受能力之间的不平衡,也是神经-内分泌-免疫网络对身体机能影响的综合表现,使机体处于一种多器官功能紊乱的病理状态。