Further studies on the chronotherapy of asthma with inhaled steroids: The effect of dosage timing on drug efficacy

Background: Chronotherapy studies with inhaled corticosteroids have shown optimal therapeutic benefit when steroids are administered four times per day (QID) or once daily at 3 PM.Objective: This study evaluated whether more convenient once-daily dosage times (8 AM and 5:30 PM) produce improvement in asthma equivalent to QID.Methods: Efficacy outcome measures included FEV₁, peak expiratory flow rates, bronchial responsiveness, use of β₂-agonists, nocturnal awakenings, and responses to a quality of life questionnaire. Systemic effects were blood eosinophil count, cortisol level, 24-hour urinary cortisol, and evaluation for oral candidiasis and dysphonia.Results: Baseline measurements for all three treatment groups were similar. For morning peak expiratory flow rate, significant improvement was seen for the QID group (p = 0.001) and the 5:30 PM group (p = 0.003), but not the 8 AM group (p = 0.75). For evening peak expiratory flow rate, significant improvement was seen for the QID group (p = 0.005) and the 5:30 PM group (p = 0.01), but not for the 8 AM group (p = 0.47). There were significant improvements in all other outcome variables for each group except PC₂₀. There was a significant improvement in PC₂₀ only in the QID group. The systemic effects of the three regimens were comparable.Conclusion: Dosing of inhaled steroid at 5:30 PM had no increased systemic effects and produced efficacy similar to QID dosing. Dosing at 8 AM did not produce results consistently comparable to QID dosing. Optimal once-daily dosing of inhaled steroid is between 3 PM and 5:30 PM.     

IPFM，MIPFM模型产生的仿真心率变异性信号的周期图与AR谱分析研究

为了研究不同心电序列转换方式及不同谱估计方法对心率变异性（ＨＲＶ）信号谱分析结果的影响，本文对积分脉冲频率调制（ＩＰＦＭ）模型及修正积分脉冲频率调制（ＭＩＰＦＭ）模型在输入不同振幅与频率的正弦信号时所产生的随机点过程，用两种心电序列转换方法进行转换得到仿真ＨＲＶ信导；然后，采用周期图与自回归（ＡＲ）谱估计方法计算这种厉真ＨＲＶ信号的功率谱。研究结果表明：①对于ＭＩＰＦＭ模型产生的随机点过程，同一心电序列转换方法所得出的仿真ＨＲＶ信号的ＡＲ谱与周期图的谱峰功率估计基本一致；而对ＩＰＦＭ模型则不完全一致。②ＭＩＰＦＭ模型仿真实验表明，对实际ＨＲＶ信号谱分析，使用低，高频谱峰功率比（ＲＦ）作为反映心脏自主神经张力平衡的指标时，除心电序列传换及谱估计方法可能造成的误差外，当低频谱峰靠近极低频谱峰时，根据ＲＦ值解释生理实验结果会有校大误差。③座分析实际ＨＲＶ信号的工作中，不同心电序列转换方式产生的伪谐波对ＨＲＶ谱分析结果的影响不大。     

基于稀疏分解法的单次诱发电位提取

迭代加权稀疏分解法是按照白噪声在小波的多分辨结构中的二尺度关系来确定求最小l1模优化问题时的加权系数,并通过一个迭代过程来逐步消除强噪声的影响。通过对视觉诱发电位的单次提取的研究说明了这种方法具有良好的单次提取效果,其实验结果支持单次提取的视觉诱发电位是不相同的观点。     

Factors affecting the size of the detour effect in the kinaesthetic perception of Euclidean distance

Three experiments investigated the mechanisms by which we estimate Euclidean distances on the basis of kinaesthetic cues. In all experiments, blindfolded participants followed straight and curvilinear paths with a stylus. Then, with a straight response movement, they estimated the distance between the end-points of the previously explored path. Experiment 1 was designed to validate the hypothesis—made on the basis of results from a previous study—that errors in the kinaesthetic estimations of distances (detour effect) originate from the difficulty to decompose the displacement vector into relevant and irrelevant components, which would become more severe at points of inflection. Using elliptic paths (no inflections), we demonstrated that errors are indeed reduced considerably. The role of the orientation of the work plane was investigated in Experiment 2 in which the same paths used in our previous study were oriented in the frontal rather than the horizontal plane. The results indicate that the detour effect is independent of the orientation. Moreover, despite the asymmetry that gravity introduces between upward and downward movements, errors in the two directions are almost identical. Experiment 3 addressed two issues. First, we demonstrated that introducing a delay between the exploration of the path and the response did not alter significantly the pattern of errors. By contrast, we demonstrated that errors are severely reduced when the number of paths to be explored is reduced by half. The results of the three experiments are discussed within the context of current theories of sensori-motor coding.     

Characteristics of\dot V_A /\dot Q distributions recovered from inert gas elimination datadistributions recovered from inert gas elimination data

The resolving powers of the enforced smoothing and log-normal parametric estimation techniques in recovering ventilation/perfusion ratio distributions were evaluated using noisy inert gas elimination data simulated from hypothetical distribution functions representing various degrees of heterogeneity. The resolving powers were assessed in terms of the statistical recoverabilities of the shunt, dead space, modality, and modal moments characterizing the perfusion distribution. For all distributions tested, both modal mean and shunt were estimated by either technique with sufficient accuracies. Modal dispersions (σ) were consistently overestimated by up to 0.15 decade for narrow distributions, but the mean errors became negligible for σ greater than 0.2 decade. As compared with the shunt, the dead space estimates were more variable and biased, probably due to their indirect estimation from the perfusion distribution, which was imperfectly recovered. Both broad unimodal and widely separated bimodal or trimodal distributions (σ>0.6 decade) were recovered as bimodal distributions of similar forms, so that detection of modality was difficult. The recoveries by both techniques were comparable in most cases studied, except that parametric estimation generally tended to be more sensitive to measurement errors and was computationally less efficient. These results provide a useful basis for the interpretation of distributions obtained from empirical inert gas data.     

鼻咽癌调强放射治疗的剂量验证

目的:对接受调强放射治疗的鼻咽癌病人进行治疗前的剂量验证.材料和方法:利用电离室,胶片和验证模体对39个接受调强放射治疗的鼻咽癌患者,在治疗开始前进行绝对剂量和相对剂量验证.绝对剂量验证主要在两个位置进行:一个在等中心位置,另一个在离等中心4cm靠进腮腺的位置.相对剂量主要用体模对单野和整个计划的剂量分布进行验证.将得到的剂量分布利用分析软件与计划中的剂量分布进行分析比较.利用剂量偏差(dose difference)、吻合距离(distance to agreement,DTA)、γ指数等参数来测量剂量验证的偏差.结果:中心点和腮腺边上点的平均绝对误差分别为2.70%和3.03%.对于测量感兴趣区域(ROI,region of interested)的相对误差的测量,90%的测量都在设定的标准(3%,3 mm)之内,对于未能达到剂量偏差和间距偏差标准的区域,结合γ分析后一般也可以得到满意的结果.结论:验证结果表明实际测量剂量分布与计划计算的剂量分布符合的相当理想.     

Acute and Subacute Toxicity of Aspilia Africana Leaves

This study was designed to evaluate the toxicity of the aqueous extract of Aspilia africana leaves. Oral doses of 500 mg/kg and 1000 mg/kg were administered for 28 days to rats after every 2 days for sub-acute toxicity. For acute toxicity, 5 doses of 2, 4, 8, 12 and 16g/Kg body weight were investigated in mice. The control groups consisted of mice or rats administered with distilled water. The signs of toxicity fluctuated lightly from one mammal to another throughout the experiment. The liver, kidneys and heart weight of rats revealed no significant differences between the test groups and the control. The results indicated that the medium lethal dose (LD₅₀) was found to be greater in females than males with an average of 6.6g/Kg body weight for both sexes. Regardless of the significant differences observed at certain points in some biochemical parameters (ALT, AST, ALP, Creatinine and Glutathione); none showed any linear dose responsiveness. On the other hand, most of the parameters investigated were found to be gender dependent. These results suggested that A Africana can be classified among substances with low toxicity.     

X(γ)刀输出吸收剂量的测量与验证

目的：目前，国内X（γ）刀的国家检定规程正在起草之中，本文的目的是为X（γ）刀剂量测量提供合理的设备与吸收剂量计算方法。材料与方法：利用德国PTW-UNIDOS剂量仅与有效体积为0．015cc的针尖电离室及自制的小体积半导体探测器相匹配，在160mm直径的有机玻璃球形模体内测量X（γ）刀的输出吸收剂量，并验证其治疗计划的实际输出剂量，得到较满意的结果。结论：为了保证剂量的准确度，X（γ）刀治疗计划系统的实际输出剂量应定期在现场测量与验证，所用探测器的直径应小于射野直径的1／2，小灵敏体积的半导体探测器适宜X（γ）刀小野(如：Ф4mm)的测量。     

Development and characterization of DNAzyme candidates demonstrating significant efficiency against human rhinoviruses

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基于椭圆方程的三维心脏超声图像的位移场估计

三维超声心动图技术能使医生直观地看到心脏整体和各部分的运动，在临床得到重视。在三维超声心动图技术中，如何定量的描述心脏中某个组织的运动状况极具临床意义。本研究提出了一种基于椭圆偏微分方程的二尖瓣三维运动估计方法。该方法直接在三维超声图像的位移场上进行了运动估计，避免了传统运动估计方法，如光流法，需要标定的缺点。本研究首先建立一个二次误差指标函数，然后利用变分法导出了三维空间下的一组椭圆型偏微分方程。这类方程有着比较成熟的数值解法，利用了有限差分法，对多个三维超声数据立方体进行了计算，结果证明这类方法是有效的。