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81.
Objectives: There is no consensus yet on how to determine which patients with cognitive impairment are able to drive a car safely and which are not. Recently, a strategy was composed for the assessment of fitness to drive, consisting of clinical interviews, a neuropsychological assessment, and driving simulator rides, which was compared with the outcome of an expert evaluation of an on-road driving assessment. A selection of tests and parameters of the new approach revealed a predictive accuracy of 97.4% for the prediction of practical fitness to drive on an initial sample of patients with Alzheimer's dementia. The aim of the present study was to explore whether the selected variables would be equally predictive (i.e., valid) for a closely related group of patients; that is, patients with mild cognitive impairment (MCI).

Methods: Eighteen patients with mild cognitive impairment completed the proposed approach to the measurement of fitness to drive, including clinical interviews, a neuropsychological assessment, and driving simulator rides. The criterion fitness to drive was again assessed by means of an on-road driving evaluation. The predictive validity of the fitness to drive assessment strategy was evaluated by receiver operating characteristic (ROC) analyses.

Results: Twelve patients with MCI (66.7%) passed and 6 patients (33.3%) failed the on-road driving assessment. The previously proposed approach to the measurement of fitness to drive achieved an overall predictive accuracy of 94.4% in these patients. The application of an optimal cutoff resulted in a diagnostic accuracy of 100% sensitivity toward unfit to drive and 83.3% specificity toward fit to drive. Further analyses revealed that the neuropsychological assessment and the driving simulator rides produced rather stable prediction rates, whereas clinical interviews were not significantly predictive for practical fitness to drive in the MCI patient sample.

Conclusions: The selected measures of the previously proposed approach revealed adequate accuracy in identifying fitness to drive in patients with MCI. Furthermore, a combination of neuropsychological test performance and simulated driving behavior proved to be the most valid predictor of practical fitness to drive.  相似文献   

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The Gorlin (naevoid basal cell carcinoma) syndrome is an autosomal dominant disorder consisting principally of naevoid basal cell carcinomas, odontogenic keratocysts, skeletal abnormalities, and intracranial calcification. We report the prenatal detection of the Gorlin syndrome by ultrasonography in a fetus with macrocephaly and mild ventriculomegaly.  相似文献   
84.
Fetal cerebral ventriculomegaly (VM) is diagnosed when the width of one or both ventricles, measured at the level of the glomus of the choroid plexus (atrium), is ≥ 10 mm. VM can result from different processes: abnormal turnover of the cerebrospinal fluid (CSF), neuronal migration disorders, and destructive processes. In a high percentage of cases, it is associated with structural malformations of the central nervous system (CNS), but also of other organs and systems. The rate of associated malformations is higher (≥60%) in severe VM (>15 mm) and lower (10–50%) in cases of borderline VM (10–15 mm). When malformations are not present, aneuploidies are found in 3–15% of borderline VM; the percentage is lower in severe VM. The neurodevelopmental outcome of isolated VM is normal in > 90% of cases if the measurement of ventricular width is between 10 and 12 mm; it is less favorable when the measurement is > 12 mm. Copyright © 2009 John Wiley & Sons, Ltd.  相似文献   
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The prenatal detection of scaphocephaly, an isolated form of craniosynostosis, is presented. The diagnosis was made at 34 weeks of gestation in a woman with polyhydramnios. The ultrasound appearance and postnatal follow-up are presented.  相似文献   
87.
目的针对低温环境下锂离子电池特性显著变化问题,为大规模锂离子电池组在极地科考船混合动力系统上的应用提供理论依据,方法对10 Ah高功率三元镍钴锰酸锂电池低温特性展开实验研究,结合实验数据,利用基于遗忘因子的递推最小二乘算法(FFRLS)分别与两种改进的卡尔曼滤波算法(AEKF、UKF)组成的串联观测器在线估计电池荷电状态(SOC)。结果在25~-30℃时变温度环境的改进DST工况下,FFRLS-AEKF算法的SOC估计精度略高于FFRLS-UKF算法,其最大估计误差为3.04%,均方根误差为0.69%。结论相比EKF与RLS-EKF算法,更好的模型参数与噪声信息的自适应性使FFRLS-AEKF算方法有更高的SOC估计精度与收敛性。  相似文献   
88.
碱渣缓和湿式氧化处理工艺的工业应用   总被引:1,自引:0,他引:1  
在碱精制过程中,会产生高污染物含量的碱渣,其中COD、硫化物和酚的排放量占炼油厂污染物排放量的20%~70%。它不仅是炼油厂的主要恶臭污染源,而且还直接影响了污水处理设施的正常运转和污水处理合格率。为了解决这一难题,抚顺石油化工研究院结合我国国情,针对碱渣的特性、开发了缓和湿式氧化工艺,并在上海、安庆、大庆、湛江及长岭等石化企业推广应用,取得了满意的效果。实践表明:采用缓和湿式氧化工艺处理碱渣可使其中的硫化物含量小于5mg/L,同时降低COD和酚的含量。  相似文献   
89.
敦煌市鸣沙山月牙泉自然遗产保全的研究   总被引:6,自引:0,他引:6  
鸣沙山月牙泉自然遗产是世界上罕见的奇特沙漠景观。随着当地旅游业的发展和地下水的不合理开采利用,使月牙泉呈现干涸的趋势,鸣沙山的生态景观受到严重破坏。为了保全这一自然遗产,通过实地考察和数据资料的比较分析研究,提出4个方面的措施:第一,合理开发利用祁连山雪山融水、“引哈济党”,解决区域的用水水源问题;第二,狭管效应、生物降解被(BiodegradableScreen)护岸、生态理念,改善月牙泉形成的地理环境;第三,建立绿色植被隔离带;第四,建立国家级沙漠公园。  相似文献   
90.
针对不对称大底板多塔楼隔震结构体系,通过建立地震响应的动力分析简化模型,推导出不对称大底板多塔楼隔震结构体系地震作用下的运动方程。对一实际的不对称大底板多塔楼隔震结构进行地震响应仿真分析,探讨塔楼质量偏心率和塔楼质量比对结构周期比、位移比和层剪力比的影响。结果显示,不对称大底板多塔楼隔震结构扭转角主要由隔震层产生;与不隔震结构相比,不对称大底板多塔楼隔震体系的扭转角减小,可取得较好的减震效果;塔楼与底板的位置分布和质量分布会影响体系的扭转效应和减震效果,应尽量使塔楼的质心与底板质心重合,塔楼质量分布均匀,以减小结构的扭转效应,提高减震效果。  相似文献   
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