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We propose a high order finite difference linear scheme combined with a high order bound preserving maximum-principle-preserving (MPP) flux limiter to solve the incompressible flow system. For such problem with highly oscillatory structure but not strong shocks, our approach seems to be less dissipative and much less costly than a WENO type scheme, and has high resolution due to a Hermite reconstruction. Spurious numerical oscillations can be controlled by the weak MPP flux limiter. Numerical tests are performed for the Vlasov-Poisson system, the 2D guiding-center model and the incompressible Euler system. The comparison between the linear and WENO type schemes, with and without the MPP flux limiter, will demonstrate the good performance of our proposed approach.  相似文献   
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目的:通过对同一患者双眼不同手术方式的自身对比,了解飞秒扫描后改SBK手术的疗效差异,为不同患者屈光手术方式的选择提供临床指导依据。方法回顾分析2例右眼行飞秒激光小切口透镜取出术( SMILE),左眼SMILE术中负压环脱失和激光扫描不良透镜分离困难而改行机械刀制瓣准分子激光手术( SBK)的患者,比较术后视力、等效球镜( SE)、对比敏感度( CSF)、波前像差( HAOS)以及泪膜破裂时间( BUT)、泪液分泌功能试验( Schimer I)和SPEED、OSDI干眼症状问卷调查分析差异。结果(1)术后个月,均能达到最佳矫正视力(BSCVA),等效球镜均在±0.75 D以内,双眼比较无显著性差异。(2)CSF的比较,左右眼无显著性差异,略低于正常水平。(3)术后3个月,BUT和Schimer检查中,双眼无显著性差异。(4)HAOS比较中,总像差RMS和高阶像差这两项, SMILE眼低于SBK眼;球差(S)的比较,SMILE眼高于SBK眼。(5)SPEED和OSDI问卷评分双眼无显著差异。结论 SMILE失败眼改SBK后视觉质量与SMILE眼无显著差异,其视觉质量、疗效不受影响。  相似文献   
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摘 要 目的 了解脑卒中患者运动自我效能及生活质量水平并探讨两者的相关性。方法 采用一般资料调查表、运动自我效能量表(ESES)和脑卒中影响量表(SIS)对福州市2所三甲医院202例脑卒中患者进行问卷调查。结果 脑卒中患者运动自我效能总得分为(30.72±2.94)分,生活质量总得分为(67.14±4.54)分,均处于中等水平;患者运动自我效能总得分与生活质量总得分及力气、情绪、交流、日常生活活动能力、移动能力和手功能6个维度得分均呈正相关关系(P<0.01)。结论 脑卒中患者运动自我效能与生活质量密切相关,提示医护人员可以通过提高脑卒中患者运动自我效能来促进其生活质量的提升。  相似文献   
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This study re-explored the nature of verbal short-term memory (STM) deficits in children with specific language impairment (SLI), by distinguishing item and serial order STM processes. Recent studies have shown serial order STM capacity to be a critical determinant of language development, relative to item STM. In Experiment 1, 12 children with SLI, 12 age-matched children and 12 language-matched children were administered serial order recognition and reconstruction tasks. Experiment 2 assessed implicit serial learning abilities via a Hebb learning task. The SLI group showed impaired performance for the serial order reconstruction and recognition tasks, relative to language-matched and/or age-matched control groups. However, normal serial position effects were observed in all SLI children in the serial order reconstruction task, suggesting normal coding of serial position information. Similarly, performance on the Hebb serial learning task was at chronological age appropriate levels. Experiment 3 showed that the group differences observed for the serial order STM tasks in Experiment 1 disappeared when the SLI group was compared to a mental age-matched control group. Experiment 4 showed similar performance levels in the SLI group and the mental age-matched control group for a nonword recognition task assessing item STM capacities. This study shows that children with SLI have no specific impairments for serial order and item STM components but that poorer general cognitive efficiency is related to functional limitations in verbal STM tasks. The data are in line with limited information processing accounts of SLI.  相似文献   
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Membrane order was measured in the erythrocyte ghost membranes of DSM-III schizophreniform disorder (SF), DSM-III schizophrenic (SCZ) and DSM-III manic (bipolar) (M) patients and a group of age- and sex-matched controls. Fluorescence polarization with the probe 1,6-diphenyl1-1,3,5-hexatriene was used to determine the steady-state fluorescence anisotropy (rs). The SF group showed a significant increase in rsrs = 0.037) from the control group. Although the means were not significantly different, 3 of 8 Ms and 5 of 8 SCZs also had rs values > the highest control value. Thermotropic behavior of the membranes was evaluated over the range of 40 to 20°C. No difference among groups in membrane enthalpy was detected. Thus, the differences in rs appear to be associated with differences in entropy. Phosphatidylcholine (PC) levels, which were known to be abnormal in these patients, were compared with the rs values. A significant (P < 0.001, R= -0.63) linear correlation between rs and membrane PC levels was observed. Overall these data further support the view that unusual membrane biophysical factors may occur with high frequency in the psychoses and affective disorders.  相似文献   
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We focus on the Fisher information matrix used for design evaluation and optimization in nonlinear mixed effects multiple response models. We evaluate the appropriateness of its expression computed by linearization as proposed for a single response model. Using a pharmacokinetic–pharmacodynamic (PKPD) example, we first compare the computation of the Fisher information matrix with approximation to one derived from the observed matrix on a large simulation using the stochastic approximation expectation–maximization algorithm (SAEM). The expression of the Fisher information matrix for multiple responses is also evaluated by comparison with the empirical information obtained through a replicated simulation study using the first‐order linearization estimation methods implemented in the NONMEM software (first‐order (FO), first‐order conditional estimate (FOCE)) and the SAEM algorithm in the MONOLIX software. The predicted errors given by the approximated information matrix are close to those given by the information matrix obtained without linearization using SAEM and to the empirical ones obtained with FOCE and SAEM. The simulation study also illustrates the accuracy of both FOCE and SAEM estimation algorithms when jointly modelling multiple responses and the major limitations of the FO method. This study highlights the appropriateness of the approximated Fisher information matrix for multiple responses, which is implemented in PFIM 3.0, an extension of the R function PFIM dedicated to design evaluation and optimization. It also emphasizes the use of this computing tool for designing population multiple response studies, as for instance in PKPD studies or in PK studies including the modelling of the PK of a drug and its active metabolite. Copyright © 2009 John Wiley & Sons, Ltd.  相似文献   
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采用核桃仁泥外敷治疗138例(实验组)肌肉注射后皮下硬结,并与40例(对照组)采用新鲜土豆片外敷硬结法比较。结果表明:实验组患者治疗15天后Ⅰ度和Ⅱ度硬结治愈率分别为81.13%和42.25%,总有效率达92.03%,明显优于对照组(P<0.001)。  相似文献   
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目的 总结复方金荞麦颗粒治疗肺癌的疗效。方法 对1000例各种类型的肺癌患者采用复方金荞麦颗粒5g,3次·d^-1 口服,同时辅以中药汤剂治疗,3mo为1疗程,病情稳定后逐渐减量维持。结果本组1000例患者经3mo~15a以上治疗,基本治愈181例(18.1%),显效518例(51.8%),有效204例(20.4%),无效97例(9.7%),总有效率为90.3%。结论 复方金荞麦颗粒为抗肿瘤的纯中药制剂,具有明显抑制肿瘤细胞生长、增强免疫功能、提高患者生存质量等功效,尤其是对失去手术治疗机会、不能接受化疗和放疗的肺癌患者具有较好疗效。  相似文献   
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