头孢羟氨苄甲氧苄啶胶囊的褶合光谱法测定

目的 建立头孢羟氨苄甲氧苄啶胶囊中头孢羟氨苄和甲氧苄啶的含量测定方法。方法 采用褶合光谱法,不经分离同时测定两组分的含量。结果 头孢羟氨苄和甲氧苄啶的平均回收率分别为99．5％(RSD1．02％)和100．0％(RSD：1．53％n=5)。结论 该法准确、简便、快速,可用于该制剂的质量控制。     

褶合光谱法同时测定复方头孢氨苄胶囊中二组分的含量

目的：用褶合光谱法不经分离同时测定复方头孢氨苄胶囊中头孢氨苄和甲氧苄啶二组分的含量。方法：结合计算机信息处理技术,利用褶合曲线分析法同时测定复方头孢氨苄胶囊中二组分的含量。结果：头孢氨苄和甲氧苄啶的平均回收率分别为99．85％（RSD=0．47％）和100．04％（RSD=1．65％）。结论：此方法不需分离,可同时测定吸收光谱互相重叠的复方剥剂中待洲组分的含量,方法可靠,操作简单,结果准确。     

广义正交多项式在卷积求解中的应用

本文定义了一类特殊矩阵——广义正交多项式(GOP)的分离矩阵。它应用分离矩阵的分割性质及其它GOP性质,得到了卷积求解的一类新方法。两个实例充分展示了此方法在自动控制领域中的实用价值。分离矩阵还可用在时滞系统的分析、参数估计及最优控制等方面。     

褶合光谱法考察超临界流体萃取牡丹皮中丹皮酚的选择性

目的：考察采用褶合光谱法分析超临界流体萃取（ＳＦＥ）选择性的可行性。方法：以超临界流体萃取牡丹皮中的丹皮酚为例,以不同波长段 拾光谱差谱值百分比作指标,观察压力、温度、动态萃取体积、改性剂加入量等因素对萃取选择性的影响,并与超临界界流体色谱（ＳＦＣ）的结果进行初步比较。结果：褶合光谱法的差谱值方法显示改性剂量是ＳＦＥ选择性的决定因素,结果与ＳＦＣ的一致。结论：褶合光谱法可以部分替代某些色谱方法进行     

Estimation of impurity profiles of drugs and related materials. Part 9: HPLC investigation of flumecinol

Two HPLC systems have been developed for the investigation of flumecinol (3-trifluoromethyl-alpha-ethyl-benzhydrol). The reversed-phase system (LiChrosorb RP-18; methanol-water, 7:3, v/v) enables the isolation and identification of the impurities. The chiral system (Chiralcel OD; hexane-2-propanol, 98:2, v/v) separates the enantiomers of flumecinol and its impurities. The potential of spectral convolution in peak identification in HPLC impurity profiling is demonstrated by an example involving the identification of the 4'-methyl-analogue of flumecinol.     

计算机辅助褶合曲线分析法在分光光度分析中的应用——Ⅰ.复方新诺明片中SMZ和TMP的含量测定

本文在Glenn正交函数法的基础上,发展了一种计算机辅助褶合曲线分析法。本法可对混合物中各组分同时进行分别定量。在采集与波长相应的吸收度数据后,计算机将很快提供每一组份的含量以及其他统计信息。本法克服了Glenn法条件选择严格、计算繁杂以及对不相关吸收谱的限制等缺点。用本法测定复方新诺明片中SMZ和TMP的含量,结果相当满意。本文对褶合曲线法的基本原理和计算机程序设计作了扼要的介绍。     

Luria-Delbrück fluctuation analysis: Estimating the Poisson parameter in a compound Poisson distribution

Estimating the mutation rate from a Luria-Delbrück fluctuation experiment involves estimating the Poisson parameter in a compound Poisson distribution. The efficiency with which this can be estimated depends on how well the other random factors have been characterized. The assumption that cell growth can be represented as a stochastic pure birth or Yule process is biologically unrealistic but contributes little to the bias and variance of a maximum likelihood estimator of the mutation rate.     

A Second-Order Scheme with Nonuniform Time Steps for a Linear Reaction-Subdiffusion Problem

It is reasonable to assume that a discrete convolution structure dominatesthe local truncation error of any numerical Caputo formula because the fractional timederivative and its discrete approximation have the same convolutional form. We suggest an error convolution structure (ECS) analysis for a class of interpolation-type approximations to the Caputo fractional derivative. Our assumptions permit the use ofadaptive time steps, such as is appropriate for accurately resolving the initial singularity of the solution and also certain complex behavior away from the initial time.The ECS analysis of numerical approximations has two advantages: (i) to localize (andsimplify) the analysis of the approximation error of a discrete convolution formula ongeneral nonuniform time grids; and (ii) to reveal the error distribution information inthe long-time integration via the global consistency error. The core result in this paper is an ECS bound and a global consistency analysis of the nonuniform Alikhanovapproximation, which is constructed at an offset point by using linear and quadraticpolynomial interpolation. Using this result, we derive a sharp $L^2$-norm error estimateof a second-order Crank-Nicolson-like scheme for linear reaction-subdiffusion problems. An example is presented to show the sharpness of our analysis.     

Pulmonary distribution of alfentanil and sufentanil studied with system dynamics analysis

We applied a system dynamics approach to the study of the pulmonary distribution of alfentanil and sufentanil in anesthetized pigs and patients, respectively. This method allows estimation of the mean transit time through the lungs and calculation of the volume of distribution of alfentanil in the lungs. In the first part of the study the pulmonary distribution of alfentanil was studied in six anesthetized pigs during three hemodynamic states (control, partial clamping of the inferior vena cave, and complete clamping of the right pulmonary artery). In the second part of the study the pulmonary distribution of sufentanil was studied in 10 patients, scheduled for elective CABG, during and after a constant rate infusion of 10 min. Pulmonary passage of the opioids was characterized by functions of transit times, derived from the pulmonary arterial and systemic arterial concentration curves. Pulmonary distribution volumes were calculated from the mean transit time and pulmonary blood flow. Pulmonary distribution volume of alfentanil during the control measurement was significantly higher (486±88 ml) than during either partial caval clamping (346±89 ml, p<0.05) or right pulmonary artery clamping (336±56 ml, p<0.05). There was no change in the extravascular volume of distribution of alfentanil with each hemodynamic state. Pulmonary volume of distribution of sufentanil in the patients was 22.6 (10.9) L. Pulmonary distribution of opioids can be studied using system dynamics analysis, both after bolus injection and during and after infusion. This method can be used for periods beyond the initial passage of the drug through the lungs.     

基于生成对抗网络的放疗剂量分布研究

目的 探讨利用深度学习在图像处理上的优势与放疗结合是否会使放疗过程更加智能化。方法 生成对抗网络(GAN)是一种利用神经网络的生成模型,输入相关特征可生成高质量剂量分布图像。先使用随机无条件GAN进行模拟分布数据的验证,再使用条件GAN(cGAN)训练肿瘤病例的DICOMRT数据,利用靶区和器官轮廓信息直接生成剂量分布图。结果 对于理想数据验证,GAN生成模拟分布效果优良,通过提取靶区轮廓和真实剂量切片数据使用cGAN训练,得到病例计划靶体积和危及器官的剂量分布。结构中预测值与真实剂量之间最大值和平均值的绝对误差评价表现为[3.57%,3.37%](计划靶体积)、[2.63%,2.87%](脑)、[1.50%,2.70%](临床靶体积)、[3.87%,1.79%](大体肿瘤体积)、[3.60%,3.23%](危及器官-1)、[4.40%,3.13%](危及器官-2)。结论 利用GAN模型可以生成模拟分布数据,同时结合先验知识的cGAN模型可以建立靶区和器官信息与剂量分布之间的关系。通过输入靶区和器官轮廓信息直接快速生成对应的剂量分布,是剂量预测的一种有效尝试。