Kinetics of d-tubocurarine disposition and pharmacologic response in rats

After bolus intravenous dosing of d-tubocurarine (d-TC) to rats, the twitch heights of the tibialis anterior muscle indirectly stimulated were followed, and its decrease was defined as pharmacologic response of d-TC. The relation between dose and response intensity was found to be well described with Hill's equation. According to a theory proposed by Smolen, Hill's equation was also applicable to the biophase d-TC concentration-response relation; the time courses of the relative biophase d-TC concentration indicated linear kinetics with dose levels 0.15 mg/kg and the occurrence of dose-dependent disposition with 0.30 mg/kg. After bolus i.v. dosing of³H-d-TC, plasma d-TC concentration obeyed a dose-independent two compartment model with doses 0.15mg/kg, but not with 0.30 mg/kg. This finding matched the above estimated with pharmacologic data. The active metabolite was not found in plasma and urine. The extent of d-TC plasma protein binding was independent of the wide range of plasma levels and its mean (±SD) value was 30.5 (±3.8). Plasma d-TC levels and pharmacologie response intensity were well correlated by Hill's equation and a three compartment model (the general two and the biophase compartments) in the dose range 0.15 mg/kg.This work was presented at the First Japanese-American Symposium on Pharmacokinetics and Biopharmaceutics, Tokyo, July 1981, which was held in memory of Dr. Sidney Riegelman.     

洋金花最佳采收期评价

目的:探索中药材洋金花最佳采收期评价新方法的可行性。方法:将洋金花的生长过程进行Logistic生长曲线方程拟合,建立数学模型,运用有序聚类分析的方法将其生长过程划分并将各划分期拟定为采收期,以生物活性成分为指标,结合产量对洋金花最佳采收期进行评价。结果:洋金花的生长过程与Logistic生长曲线方程拟合度良好,有序聚类分析后将洋金花采收期拟定为五个时期,评价后发现与以往采收期试验研究结果有差别。结论:洋金花药材最佳采收期评价新方法可行。     

劈状区域中对称双曲组非齐次边值问题的可微分解

适当选取切边算子,引入函数的带边界的模,对文题建立先验估计,证明了高阶可微分解的存在性定理。     

Social support and individual styles of coping in the Japanese workplace: an occupational stress model by structural equation analysis

The aim of the present study was to ascertain the role of social support and individual styles of coping on employee well‐being. The subjects were intermediate managers working for a zipper and sash manufacturing company in Japan. Measurements were made of the following: depression using the Self‐rating Depression Scale (SDS), job demand, job control, social support using Karasek's Job Content Questionnaire, and of three coping styles: emotion‐oriented coping, task‐oriented coping and avoidance‐oriented coping using the Coping Inventory for Stressful Situations (CISS). Data was analysed by structural equation modeling. Each coping style had a direct effect on depression. Emotion‐oriented coping had a negative effect. On the other hand, task‐oriented coping and avoidance‐oriented coping had a positive effect. Moreover, there was an indirect effect that coping styles precede and determine the perception of social support as well as job demand and control. Social support showed a direct positive effect on depression. However, the overall impact on employee well‐being was greater for individual coping styles as compared to social support from either supervisors or co‐workers. The present study showed the effectiveness of coping strategies in the workplace. Copyright © 2003 John Wiley & Sons, Ltd.     

生育保险病种费用影响因素结构方程模型分析

目的:研究生育保险病种费用影响因素,为生育保险按病种付费提供依据.方法:抽取南京市4家医院2002/2004生育保险参保人员病历首页以及财务结算帐单1525份,用结构方程模型(SEM)方法分析.结果:临床特征、医护质量和社会经济特征三个隐变量对住院费用的影响系数分别为0.9334,0.3194,0.2230,病种临床特征对住院费用影响最大.结论:结构方程模型分析生育保险病种住院费用影响因素收到很好的效果.     

基于扩展TAM-TPB整合模型的患者基层首诊意愿影响因素研究

目的/意义 基于扩展TAM-TPB整合模型,研究影响患者参与基层首诊意愿的主要因素。方法/过程 采用结构方程模型探析患者选择基层首诊决策过程中的影响因素及其内在作用机制。结果/结论 患者主观规范、行为态度、知觉行为控制显著正向影响其参与基层首诊意愿,感知易用性和感知有用性显著正向影响行为态度和知觉行为控制,感知易用性显著正向影响感知有用性。患者对基层首诊认知存在盲区,自我效能感较弱,应不断加强对基层首诊相关政策法规的系统宣传,简化基层首诊的流程与步骤,引导居民树立科学理性的就医观念,从而增强患者基层首诊参与意愿。     

飞行员前庭刺激症状与部分生理参数及尿激素含量的关系

目的 探讨前庭刺激诱发的症状体征与同步记录的胃电图、眼震电图、经穴电位、心率变异性、皮肤温度及尿激素含量的关系。方法 记录飞行员在前庭刺激下的症状体征,并同步记录各项指标,用Ｇｒａｙｂｉｅｌ提出的评分标准,给症状体征评分,用逐步回归方法分析症状体征得分与各项生理参数的关系。结果 得出了前庭刺激前、中、后３个回归方程。结论 在实际使用时可以选择３个预测方程。     

Dual-Focus Therapeutic Ultrasound Transducer for Production of Broad Tissue Lesions

In noninvasive high-intensity focused ultrasound (HIFU) treatment, formation of a large tissue lesion per sonication is desirable for reducing the overall treatment time. The goal of this study is to show the feasibility of enlarging tissue lesion size with a dual-focus therapeutic ultrasound transducer (DFTUT) by increasing the depth-of-focus (DOF). The proposed transducer consists of a disc- and an annular-type element of different radii of curvatures to produce two focal zones. To increase focal depth and to maintain uniform beamwidth of the elongated DOF, each element transmits ultrasound of a different center frequency: the inner element at a higher frequency for near field focusing and the outer element at a lower frequency for far field focusing. By activating two elements at the same time with a single transmitter capable of generating a dual-frequency mixed signal, the overall DOF of the proposed transducer may be extended considerably. A prototype transducer composed of a 4.1 MHz inner element and a 2.7 MHz outer element was fabricated to obtain preliminary experimental results. The feasibility the proposed technique was demonstrated through sound field, temperature and thermal dose simulations. The performance of the prototype transducer was verified by hydrophone measurements and tissue ablation experiments on a beef liver specimen. When several factors affecting the length and the uniformity of elongated DOF of the DFTUT are optimized, the proposed therapeutic ultrasound transducer design may increase the size of ablated tissues in the axial direction and, thus, decreasing the treatment time for a large volume of malignant tissues especially deep-seated targets. (E-mail: jongsjeo@usc.edu)     

Nonstationary increments, scaling distributions, and variable diffusion processes in financial markets

Fat-tailed distributions have been reported in fluctuations of financial markets for more than a decade. Sliding interval techniques used in these studies implicitly assume that the underlying stochastic process has stationary increments. Through an analysis of intraday increments, we explicitly show that this assumption is invalid for the Euro-Dollar exchange rate. We find several time intervals during the day where the standard deviation of increments exhibits power law behavior in time. Stochastic dynamics during these intervals is shown to be given by diffusion processes with a diffusion coefficient that depends on time and the exchange rate. We introduce methods to evaluate the dynamical scaling index and the scaling function empirically. In general, the scaling index is significantly smaller than previously reported values close to 0.5. We show how the latter as well as apparent fat-tailed distributions can occur only as artifacts of the sliding interval analysis.     

Accuracy of Quadratic Versus Linear Interpolation in Noninvasive Electrocardiographic Imaging (ECGI)

Electrocardiographic Imaging (ECGI) is a cardiac functional imaging modality, noninvasively reconstructing epicardial potentials, electrograms and isochrones (activation maps) from multi-channel body surface potential recordings. The procedure involves solving Laplace’s equation in the source-free volume conductor between torso and epicardial surfaces, using Boundary Element Method (BEM). Previously, linear interpolation (LI) on three-noded triangular surface elements was used in the BEM formulation. Here, we use quadratic interpolation (QI) for potentials over six-noded linear triangles. The performance of LI and QI in ECGI is evaluated through direct comparison with measured data from an isolated canine heart suspended in a human-torso-shaped electrolyte tank. QI enhances the accuracy and resolution of ECGI reconstructions for two different inverse methods, Tikhonov regularization and Generalized Minimal Residual (GMRes) method, with the QI-GMRes combination providing the highest accuracy and resolution. QI reduces the average relative error (RE) between reconstructed and measured epicardial potentials by 25%. It preserves the amplitude (average RE reduced by 48%) and morphology of electrograms better (average correlation coefficient for QI ∼ 0.97, LI ∼ 0.92). We also applied QI to ECGI reconstructions in human subjects during cardiac pacing, where QI locates ventricular pacing sites with higher accuracy (≤ 10 mm) than LI (≤ 18 mm).