基于χ~2检验法的通脑活络针刺法对脑梗死患者BI指数的影响

用r×s列连表的Pearson x~2检验法,讨论通脑活络针刺法、溶栓剂法与常规法在各救治时间窗对脑梗死患者BI评分的影响,并得到结论,通脑活络针刺法在各救治时间窗的"治愈率"及较好的康复程度方面显示了显著疗效.     

双源CT4D-CTA联合灌注成像在急性脑缺血性疾病中的应用价值

目的：探讨双源CT 4维血管造影（4D- CTA）及灌注成像（CTPI）在急性脑缺血性疾病中的应用价值。方法对30例临床拟诊为急性脑缺血性疾病的患者于发病2-24h内行头颅CT平扫和全脑CTPI检查,获得脑血流量、脑血容量、平均通过时间、达峰时间等参数图,同时获得4D- CTA图像;于发病的1-3d后行MRI检查,分析CT平扫、CTPI、4D- CTA、MRI表现。结果 CT平扫发现12例有16个缺血病灶,CTPI发现26例32个缺血病灶,MRI发现25例28个缺血病灶,4D- CTA显示有20例责任血管有不同程度的狭窄或闭塞。结论双源CT 4D- CTA联合灌注成像能为急性脑缺血患者提供全面、详细的影像学信息,对急性缺血性脑梗死的早期诊断和治疗有重要价值。     

伽玛刀治疗脑转移瘤162例

@@脑转移瘤是颅内最常见的恶性病变,随着恶性肿瘤患者生存时间逐渐延长,脑转移瘤的发病率也逐渐增高。如何合理有效地治疗脑转移瘤,延长患者生存时间,提高生存质量,已越来越引起关注。我科2010-08—2012-08应用头部伽玛刀治疗脑转移瘤患者162例,共228例次,取得了满意的治疗效果,现总结报道如下。     

急性脑梗死患者脑微出血的发病情况及其危险因素分析

目的探讨急性脑梗死患者脑微出血的发病情况及其危险因素。方法选择急性脑梗死患者75例,男51例,女24例,年龄42～83（64.9±10.8）岁。行头颅CT、磁敏感成像（SWI）检查,依据脑微出血检出的结果分成阳性组（23例）与阴性组（52例）,比较两组的一般资料,探讨脑微出血发病的危险因素。结果SWI检查的检出率比CT检出率高（χ2=27.17,P＜0.05）。阳性组年龄、高血压病、糖尿病患病率均较阴性组高,差异均有统计学意义（均P＜0.05）;两组性别、血脂异常、心房颤动、冠心病、吸烟、饮酒情况比较,差异均无统计学意义（均P＞0.05）。logistic回归分析显示年龄增长、高血压病是脑微出血的独立危险因素（P＜0.05）。结论急性脑梗死患者合并存在脑微出血的比例高,SWI检查是检测脑微出血的敏感方法,年龄大、高血压病与脑微出血的发生密切相关。     

针刺镇痛和吗啡镇痛过程中脑内3H-5-羟色胺释放的研究

鉴于脑内神经细胞间的信号传递是通过突触部位神经介质的释放而实现的,因此神经介质必然在针刺镇痛过程中起重要作用。本文将脑室灌流方法与同位素技术相结合,研究家兔在清醒状态下针刺时脑内5-HT释放和痛觉之间的动态关系。先后在48只家兔上观察了脑室注射³H-5-HT后,脑室灌流液中5-HT释放和痛阈变化,发现针刺组18只家兔中半数以上在针刺提高痛阈的同时5-HT释放增加,而对照组、吗啡组及手握后肢均不增加5-HT释放。这一结果表明针刺时脑内5-HT能神经原被激活。     

脑啡肽在针刺镇痛中的作用:放射免疫测定

脑内有数种内源性吗啡样物质,它们的分布和功能意义不尽相同.为阐明内源性吗啡样物质与针刺镇痛的关系有必要对它们分别进行研究.本文采用灵敏和专一的放射免疫分析法测定了家兔和大白鼠在针麻过程中各脑区及脑脊液中两种脑啡肽的含量变化.主要结果为:(1)针刺镇痛过程中下丘脑及纹状体两种脑啡肽均明显升高;(2)家兔侧脑室注射杆菌肽能够显著增强针效和提高脑内及脑脊液中脑啡肽的含量;(3)蛋白合成抑制剂环己亚胺可以削弱针刺升高脑啡肽含量的作用,说明加速生物合成是针刺增加脑啡肽含量的机制之一;(4)手术游离下丘脑后大白鼠电针效应削弱,提示下丘脑参与了针刺镇痛过程.     

MRI检查无责任病灶脑后循环缺血患者的CT灌注成像研究

目的探讨MRI检查显示无责任病灶的脑后循环缺血(PCI)患者的局部脑血流灌注情况,探索PCI患者早期诊断的有效方法.方法选取符合PCI临床诊断的24例患者行头颅MRI检查,对未发现责任病灶的患者进一步行CT灌注成像(CTPI)检查.在CTPI图像上手绘感兴趣区域(ROI),记录病灶区与对照区的灌注参数,包括局部脑血流量(rCBF)、局部脑血容量(rCBV)、平均通过时间(MTT)和达峰时间(TTP).结果 CTPI检查发现异常灌注18例(阳性率75%),缺血灶共26处,其中小脑10处(38.5%),枕叶7处(26.9%),颞叶3处(11.5%),脑干6处(23.1%).TTP发现异常15例,且均与临床症状相对应,rCBF发现异常13例,rCBV发现异常8例.脑梗死前期分期:玉1期4例,玉2期1例,域1期5例,域2期8例.病灶区的rCBF、rCBV、MTT及TTP与对照区相比较,差异均有统计学意义(P<0.01或0.05).结论 CTPI检查通过对PCI患者进行ROI半定量分析,可客观评价脑后循环脑血流灌注情况,发现头颅MRI检查所未能发现的缺血灶,为临床诊治PCI提供依据.     

带时间窗偏好的同时配集货且需求可拆分车辆路径问题

针对带时间窗偏好的同时配集货且需求可拆分车辆路径问题,最小化派遣成本、理货成本、时间窗惩罚成本以及油耗成本之和,建立数学模型。设计混合遗传变邻域搜索算法求解问题,在算法中引入时空距离的理念,首先用最近邻插入法和Logistic映射方程生成初始种群;然后利用变邻域搜索算法的深度搜索能力优化算法;提出自适应搜索策略,平衡种群进化所需的广度和深度;设计拆分准则,为各客户设置不同的拆分服务量;提出确定车辆最优出发时间的时差推移法,减少车辆在客户处的等待时间;最后通过多组算例验证本文模型和算法的有效性。     

谱密度矩阵的对称谱窗估计

在平稳时间序列的谱分析中,估计谱密度的方法很多,谱窗估计法是常用的一种方法。采用这种方法的键是选择好的窗函数,同时要控制窗口的大小——窗函数平滑周期的范围。评选窗函数要有一个好坏的标准,例如谢衷洁与程乾生以分瓣率的高低作为评选时窗函数的标准来寻找最佳的时窗函数;作者在和中,适当控制某种对称窗口的大小,可使谱密度估计量具有渐近无偏和均方相合等优良性质,而对时间序列本身不作正态分布的假定。     

不同手法及频率针刺神经电信号的编码特征提取

神经系统通过时间空间编码的形式表征外部刺激所包含的信息,针刺作为神经系统的一种外部刺激,使神经元产生丰富的放电模式. 为揭示针刺信息传导与作用规律,设计了不同手法以及不同频率的针刺作用足三里时,采集脊髓背根神经电信号的实验.通过对放电波形进行小波特征提取和类选算法把放电波形进行归类,然后提取出不同刺激下的时间编码和空间编码特征. 接着使用平均放电率和编码异质性系数量化了不同针刺刺激下编码的特征. 研究发现捻转法与提插法产生的神经电信号差异较大, 这种差异主要表现在针刺手法对于参与编码神经元的选择性,但对于不同频率的针刺作用, 这种编码选择性并不明显.此外,数据分析中还发现了神经系统对于针刺作用的适应性和饱和特性.     

多元协方差分析用于艾滋病疗法的选择

目的:优化HAART药物治疗方案,提高治疗效果,为广大患者和医生选择艾滋病的疗法提供科学的依据.方法:以CD4细胞数的增加值作为体现治疗效果的因变量,治疗时间和初始治疗CD4细胞数为协变量,通过四组疗法分组进行多元协方差分析。结果:患者治疗效果的差异主要是由于治疗方法和治疗时间以及初始治疗cd4值的差异所致;四种疗法的疗效总体上差异显著,满足完备性条件和显著性条件的疗法疗效优劣顺序是:M4>M2≈M3≈M1.结论:多元协方差分析用于艾滋病疗法的选择对实际工作有积极的指导意义.     

神经激肽1受体拮抗剂对大鼠脑缺血再灌注的神经保护作用

目的观察大鼠局灶性脑缺血再灌注后神经激肽1受体拮抗剂对脑梗死体积、脑组织含水量及神经行为学变化的影响,探讨减轻神经源性炎症反应对脑缺血再灌注的保护作用。方法将54只大鼠分为药物组、假手术组、对照组,用线栓法建立右侧大脑中动脉缺血再灌注大鼠模型,药物组和对照组大鼠在再灌注时经尾静脉分别注入神经激肽1受体拮抗剂及生理盐水,假手术组只分离右侧颈总、颈内、颈外动脉。缺血再灌注后24h时采用免疫组化法检测P物质表达,氯化三苯基四氮唑染色法测定脑梗死体积,干-湿称重法检测脑组织含水量;分别于再灌注24h及72h时利用转棒试验和肢体不对称试验检测神经行为学变化。结果脑缺血再灌注后24h大鼠脑缺血区P物质的表达明显升高,脑组织含水量明显增加。药物组与对照组比较,脑组织含水量减少,神经功能改善。结论神经激肽1受体拮抗剂可通过抑制神经源性炎症反应而达到缺血再灌注损伤时的脑保护作用。     

A queueing theoretic methodology for the analysis of separable conflict resolution algorithms with variable length elementary events

We describe a queueing theoretic approach to the delay analysis for the class of synchronous random-access protocols consisting of a Capetanakis-type Tree Algorithm for conflict resolution and a window algorithm for channel access. Our method features a stochastic decomposition, in which a major component of the delay is viewed as a discrete time queueing problem, where each window (selected by the channel access algorithm) becomes a customer requiring service in the form of conflict resolution. This technique is sufficiently powerful to give us the distribution of the packet delay in steady state. In this paper, we extend our method to allow the durations of elementary algorithmic steps to take on a general distribution (rather than being constants), which allows us to provide a unified treatment of channels with shared errors, some types of explicit reservation systems, and Local Area Networks with carrier sensing and/or collision detection, possibly in combination with variable size packets.     

An iterated local search algorithm for the vehicle routing problem with convex time penalty functions

We propose an iterated local search algorithm for the vehicle routing problem with time window constraints. We treat the time window constraint for each customer as a penalty function, and assume that it is convex and piecewise linear. Given an order of customers each vehicle to visit, dynamic programming (DP) is used to determine the optimal start time to serve the customers so that the total time penalty is minimized. This DP algorithm is then incorporated in the iterated local search algorithm to efficiently evaluate solutions in various neighborhoods. The amortized time complexity of evaluating a solution in the neighborhoods is a logarithmic order of the input size (i.e., the total number of linear pieces that define the penalty functions). Computational comparisons on benchmark instances with up to 1000 customers show that the proposed method is quite effective, especially for large instances.     

A school bus scheduling problem

This paper introduces a school bus scheduling problem wherein trips for each school are given. A trip consists of a sequence of bus stops and their designated school. Each school has its fixed time window within which trips should be completed. A school bus can serve multiple trips for multiple schools. The school bus scheduling problem seeks to optimize bus schedules to serve all the given trips considering the school time windows. We first model the problem as a vehicle routing problem with time windows (VRPTW) by treating a trip as a virtual stop. Two assignment problem based exact approaches are then proposed for special cases and a heuristic algorithm is proposed for more general cases. Benchmark problems and computational experiments are presented. Computational experiments show the effectiveness of the proposed approaches.     

带凸资源和恶化效应的单机松弛窗口排序

研究带凸资源和恶化效应的单机窗口指派排序问题,其中窗口指的是松弛窗口,凸资源和恶化效应指的是工件的实际加工时间是其开始加工时间的线性函数,是其资源消耗量的凸函数。目标是确定工件的加工顺序,资源分配量以及窗口的开始加工时间和长度使其在总资源消耗费用(与窗口有关的排序费用)有上界限制的条件下,极小化与窗口有关的排序费用(总资源消耗费用)。获得了求解上述问题的最优算法,证明了该问题是多项式时间可解的。     

Single-machine common due window assignment and scheduling to minimize the total cost

In this paper we consider a single-machine common due window assignment and scheduling problem with batch delivery cost. The starting time and size of the due window are decision variables. Finished jobs are delivered in batches. There is no capacity limit on each delivery batch, and the cost per batch delivery is fixed and independent of the number of jobs in the batch. The objective is to find a job sequence, a delivery date for each job, and a starting time and a size for the due window that jointly minimize the total cost comprising earliness, weighted number of tardy jobs, job holding, due window starting time and size, and batch delivery. We provide some properties of the optimal solution and present polynomial-time algorithms for the problem.     

Controlling job arrivals with processing time windows into Batch Processor Buffer

We consider a two-stage manufacturing system composed of a batch processor and its upstream processor. Jobs exit the upstream processor and join a queue in front of the batch processor, where they wait to be processed. The batch processor has a finite capacity Q, and its processing time is independent of the number of jobs loaded into the batch processor. In certain manufacturing systems (including semiconductor wafer fabrication), a processing time window exists from the time instance the job exits the upstream processor till the time instance it enters the batch processor. If a job is not processed before reaching the end of its processing time window, job rework or validation is required. We model this drawback by assigning a reward R for each successfully processed job by the upstream processor, and a penalty C for each job that reaches the end of its processing time window without being processed by the batch processor. We initially assume an infinite job source in front of the serial processor and also assume that the batch processor is operated under a threshold policy. We provide a method for controlling the production of the serial processor, considering the processing time window between the upstream processor and the downstream batch processor. We then show how the serial processor control policy can be modified when the serial processor also experiences intermittent job arrival.     

公共交货期窗口的提前／延期惩罚

本讨论n个独立工件在一台机器上加工,而且加工时间服从正态分布的公共交货期窗口的提前/延期惩罚问题,在确定公共交货期窗口情况下,推导出工件的最优排序具有V型特征。