房室结逆向传导电生理特点的观察

目的研究房室结逆向传导的电生理特点。方法分析在我院行电生理检查和／或射频消融的成年患者中电生理资料比较完整的300例患者的房室结逆传电生理特点。结果射频消融术后有161例（54％）有房室结逆传。有逆传患者的前传功能要好于无逆传的患者，对于术后存在室房逆传的患者，逆传功能均明显差于前传功能。射频消融术后有28例（17％）经房室结逆传最早激动冠状静脉窦口，其逆传功能较最早激动希氏束电图的病例相比要差，而两者的前传功能差异无统计学意义。结论射频消融术后54％的患者存在房室结逆传，可能是正常人群中室房逆传的真实反映。有室房逆传患者的房室结前传功能优于无室房逆传者，也优于其本身的逆传功能。房室结逆传冲动进入心房可能存在两条不同的通路。     

同伴支持、父母支持和青少年自我价值感初探

目的：探讨实际的同伴支持、感知到的同伴支持、感知到的父母支持、对同伴支持的重要性评价、对父母支持的重要性评价和自我价值感之间的关系。同时也考察了青少年的同伴接受性。方法：用社会测量法和自我报告法对285名青少年进行集体测试。结果：①社会测量法表明青少年也可以被分为受欢迎的、被拒绝的、被忽略的、和有争议的；②感知到的同伴／父母支持和自我价值感之间存在显著正相关；高低实际同伴支持两组被试在感知到的同伴支持上存在显著差异。但在自我价值感上不存在显著差异；（固在所有被试中，只有对初三学生来说，对同伴／父母支持的重要性评价在感知到的同伴／父母支持和自我价值感之间起到调节作用。结论：感知到的同伴／父母支持可以用来预测青少年的自我价值感：对初三学生来说，对同伴／父母支持的重要性评价可以在感知到的同伴／父母支持和自我价值感之间起到调节作用。     

An Implantable Aortic Valvo-pump for Destination Therapy

To investigate the possibility of a long-term applicable left ventricular assist device, a 23 mm outer diameter and 31 g weight implantable aortic valvo-pump was developed. It consists of a rotor and a stator; the rotor has a driven magnets assemble and an impeller, the stator has a motor coil with iron core and a outflow guide vane. The device locates the position of aortic valve, delivers the blood directly from left ventricle to aorta. Neither connecting conduits nor “bypass” circuits are necessary. Therefore, the device has promisingly better antithrombogenicity than other heart pumps. In hemodynamic testing, the pump can produce a blood flow of 7 l/min volume with 50 mmHg pressure increase at 15,000 rpm rotating speed, and at zero flow rate the pump can maintain a diastolic pressure over 80 mmHg at same rotating speed. For further studies the blood compatibility and the durability of the device are of most importance.     

不同营养支持方式对肠外瘘患者人体组成改善作用之比较

目的观察不同营养支持方式对肠外瘘患者人体组成的改善作用。方法30例肠外瘘患者分成两组各15例,分别给予全肠外营养支持(TPN)或全肠内营养支持(TEN),观察10d前后患者人体组成及血清胰岛素样生长因子-1(IGF-1)的变化。结果10d后所有患者的体重指数(BMI)与体细胞群(BCM)显著改善,而TEN组患者10d前后BCM增加幅度更明显,分别为(27.5±0.8)kg和(29.0±0.6)kg,Day10与Day0相比,P<0.01。两组患者总体水(TBW)与细胞内水(ICW)均增加,尤其ICW,Day10与Day0相比,TEN组P<0.01;TPN组P<0.05。血清IGF-1在两组患者治疗后均有显著上升,TEN组增加幅度更明显,Day0为(175.0±32.9)ng/ml,Day10为(255.5±34.1)ng/ml,与Day0比较,P<0.01;与TPN组比较,P<0.05。IGF-1的变化与BCM的改善显著正相关(r2=0.16,P<0.05)。结论营养支持治疗能显著改善肠外瘘患者的体细胞群,纠正细胞内、外水的异常分布,而EN作用更明显。     

躯干运动和负重时对足底支撑面侧向横移的姿势控制

目的:本研究假设自主运动命令和姿势控制信号间有冲突,因此设计在附加重物和不同自主任务的同时给予足底一个模拟受滑的干扰(横移)来观察姿势变化并分析其是否受冲突命令或者力学参数的影响.方法:受试者在执行各种不同的自主任务时,随机给予足底支撑面一个左侧或右侧的横移干扰.这些不同的自主任务包括不负重静止站立、静止站立单手负重5kg、负重5kg站立并躯干静止侧屈15°、负重5kg动态地提重物和放重物5项任务.测量和分析下列参数:中心压力的侧位移(COP)、躯干和股部在冠状面上的角位移和腹内压(IAP).结果:干扰离开质量(向右)、始反应超射的幅度、达到终平衡的时间和达到平衡前COP位移的次数都增加,这种情况可以看作是为了再获得平衡的姿势反应效率降低,因此,如果质量的重力效果能对抗干扰,则再获得平衡的反应效率甚至可以被增进.结论:提重和负重是危害姿势反应效率的因素,因为提重和负重改变了重力效果,加大了对躯干的干扰.在动态条件下躯干的运动不是被横移干扰增强就是被横移干扰抵消,并没有显著地影响改变最终平衡位置姿势校正的效应.因此附加任务的同时给一个支持面上的横移干扰,姿势控制的效应可以被抵消.这个减低的效应可以引起脊柱周围结构的负荷增加和增加受伤的危险性.但是,在恰当地放置负重的位置时,反而可以增进躯干控制和协助恢复姿势平衡.     

社会支持对考试应激的影响

目的了解社会支持对考试应激的影响。方法采用焦虑自评量表和社会支持量表分别对７２７个学生考试前１个月、考试期间考试焦虑分数及社会支持情况进行调查，比较分析考试焦虑分数与社会支持因素的关系。结果考试焦虑分数与客观支持、来自同学和老师的主观支持以及社会支持的利用度成反比。结论家长和学校给予学生足够的社会支持，以及让学生参加适当的社会活动，培养他们利用社会支持的能力，有助于让学生减缓考试应激的水平     

失眠症患者心理防御机制与社会支持的相关研究

目的　探讨失眠症患者心理防御特征和社会支持 ,并分析两者的关系。方法　采用心理防御方式问卷 (DSQ )、社会支持评定量表 (SSRS)对失眠症患者和正常健康者各 5 0例进行评定。结果　患者组心理防御方式 (不成熟型、中间型防御因子和掩饰因子的因子分高 ,成熟防御因子分低 )和社会支持 (社会支持总分、主观支持分、对支持利用度低 )与对照组相比差异有显著性 (P <0 .0 5或 0 .0 1) ;相关分析发现 ,患者组不成熟防御机制与SSRS的支持总分、主观支持分、对支持利用度呈负相关 (P均 <0 .0 5 ) ,中间型防御机制与SSRS的主观支持呈负相关 (P <0 .0 5 )。结论　失眠症患者心理防御机制的成熟程度较正常人低 ,社会支持差 ,两者存在一定的关系。     

Radiofrequency Catheter Ablation of the Anterosuperior and Posteroinferior Atrial Approaches to the AV Node for Treatment of AV Nodal Reentrant Tachycardia

Catheter Ablation Techniques in AVNRT. Radiofrequency catheter ablation has been established as a first-line curative treatment modality in patients with symptomatic AV nodal reentrant tachycardia (AVNRT). The successful sites of stepwise catheter ablation approaches of the so-called fast and slow pathways strongly suggest that AVNRT involves the atrial approaches to the AV node. The typical fast pathway ablation sites are located anterosuperior toward the apex of the triangle of Koch, which also contains the compact AV node, whereas the usual slow pathway ablation sites are located posteroinferior toward the base of the triangle of Koch at a greater distance to the compact AV node and bundle of His. Accordingly, ablation studies with large patient cohorts have demonstrated that fast pathway ablation carries a higher risk of inadvertent complete AV block. Thus, the slow pathway is clearly the primary target site, and fast pathway ablation is rarely necessary. Different approaches for slow pathway ablation have been elaborated: anatomically oriented stepwise techniques, ablation guided by double potentials recorded within the area of the slow pathway insertion, and combined techniques. The modern concept of AVNRT suggests that this arrhythmia involves the highly complex three-dimensional nonuniform anisotropic AV junctional area. Accordingly, mapping and ablation studies demonstrated that the anterior approach is not identical with fast pathway ablation, and the posterior approach is not identical with slow pathway ablation. Therefore, it is essential for interventional electrophysiologists to familiarize themsdves with the anatomic and electrophysiologic details of this complex and variable specialized AV junctional region. In this review, the anatomic and pathophysiologic aspects of the AV junctional area as they relate to interventional therapy are summarized briefly, and the catheter techniques for ablation of the so-called fast and slow AV nodal pathways for the treatment of AVNRT are described.     

Semipermeable Hollow Fiber Membranes in Hepatocyte Bioreactors: A Prerequisite for a Successful Bioartificial Liver?

Abstract: Recent studies have shown that liver support systems based on viable hepatocytes can prolong life in animal models of acute liver failure. Now the time has come to elucidate the design characteristics that are essential to construct an efficient bioreactor. The gold standard remains the intact liver. Despite the very high cell density in this organ, individual cell perfusion is guaranteed resulting in low diffusional gradients which are essential for optimal mass transfer. These conditions are not met in bioreactors based on hollow fiber membranes. Moreover, the semipermeable membranes can foul and act as a diffusional barrier between the hepatocytes and the blood or plasma of the recipient. We devised a novel bioreactor for use as a bioartificial liver that does not include hollow fiber membranes for blood or plasma perfusion. The device is based on an integral oxygenator and a nonwoven polyester matrix material for hepatocyte culture as small aggregates. The efficacy of this original design was tested in rats with liver ischemia. Preliminary results show statistically significantly improved survival; life was prolonged 100% compared to the control experiments.