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161.
对某蓄水工程路基挡墙的安全性进行验证,发现抗滑移和抗倾覆均满足要求,但墙身应力超标较多,墙身不满足抗拉要求,墙身产生裂缝,强度急剧下降,抗倾覆安全系数也会降低。该路基挡墙经必要的设计修正后,取得了良好的经济效益。  相似文献   
162.
Objective: To determine whether the standard Spanish driving test (ASDE test) was able to identify patients with Parkinson's disease (PD) at risk of unsafe driving and to examine the relationship between the ASDE test and the Useful Field of View (UFOV) as well as with a battery of neuropsychological tests in drivers with PD.

Methods: Thirty-seven patients with PD and 33 controls matched by age and education level were included in an observational study. All participants were active drivers and patients with PD underwent study procedures after taking the medication in the “on” period. Subjects with a Mini-Mental State Examination (MMSE) score ≤ 24 were excluded. Neuropsychological tests (Repeatable Battery for Neuropsychological Status [RBANS], Trail Making Test [TMT-A and -B], and Block Design test), driving performance tests (ASDE Driver Test and UFOV), and daytime sleepiness (Epworth Sleepiness Scale) were assessed.

Results: The PD group performed significantly worse than healthy controls in the ASDE Motor Coordination tests. No significant differences were observed in anticipation speed, multiple reaction time, concentrated attention, and resistance to monotony. All participants successfully completed the UFOV tests. Statistically significant differences between patients with PD and controls were found in processing speed (UFOV1; P =.03) and more patients with PD were found in the categories of higher driving risk levels (P =.03). In addition, patients with PD showed worse scores than healthy controls in visuospatial capacities (Line Orientation), psychomotor speed (Coding and TMT-A), memory (List Recognition, Story Recall), and executive function (TMT-B). The driving tests (ASDE and UFOV) showed a low sensitivity and a high specificity but a higher percentage of patients in the PD group failed in multiple reaction time, concentrated attention, and resistance to monotony. In addition, 18.9% of patients with PD showed a cutoff of 4 for UFOV risk. In the discriminant analysis, Line Orientation (visuospatial/constructive domain) and Figure Recall (delayed memory) were found to be statistically significant with a rate of correct classification of unsafe drivers with PD of 78.2%. In addition, normal results on the Line Orientation item were associated with a 1.5 times higher probability of non-risky driving in the multivariate analysis.

Conclusions: At early stages of the disease, about 19% of patients with PD showed difficulties that may affect their driving capabilities. Line Orientation and Figure Recall are useful to alert clinicians to the risk of unsafe driving. For this reason, patients with PD should be evaluated for driving abilities more regularly to determine the extent of deficits that may influence driving performance.  相似文献   

163.
学龄儿童呼吸系统疾病、症状影响因素研究   总被引:1,自引:0,他引:1  
用非条件 Logistic回归分析方法研究空气污染对学龄儿童呼吸系统疾病、症状的影响。结果表明 ,控制年龄、性别、父亲和母亲受教育水平、住房结构、家庭烹饪燃料、厨房抽风设备、被动吸烟等因素 ,污染区儿童因呼吸系统疾病住院、患支气管炎和出现喘息症状的危险性分别是相对清洁区的 1 .6、1 .5和 1 .2倍 ;不感冒咳嗽或不感冒咳痰的发生与室外空气污染水平的关系均不明显 ;家庭烹饪使用不洁燃料、厨房通风不良、被动吸烟使喘息症状的发生机会增加 (尤其是厨房的通风状况不良 )  相似文献   
164.
This study investigated total arsenic (As) and As species contents of oysters (Crassostrea gigas) in different production areas, seasons and sea locations on the southwestern coast of Taiwan. Analytical results indicate that contents of total As, arsenite, arsenate, dimethylarsinic acid, monomethylarsonic acid and arsenobetaine in oysters are 9.90 ± 3.68, 0.091 ± 0.104, 0.033 ± 0.038, 0.529 ± 0.284, 0.037 ± 0.046 and 3.94 ± 1.33 mg/g (dry wt), respectively. A ratio of inorganic As concentrations to total As concentrations is 1.26%. Total As contents of oysters cultured in the outer sea are statistically significantly lower than those of oysters cultured in the inner sea. The total As contents of oysters is the highest in Putai, where the blackfoot disease prevails. The low As contents in oysters is attributed to the low temperature in winter, which slows the metabolism of oysters. A maximum value is 33.37 μg/g (dry) in Putai in spring, because a considerable amount of aquacultural waste water with high As contents is discharged into adjacent drainage channels and rivers there during that season.  相似文献   
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为了探讨高原地区尘肺患者死因特点及其规律,对青海省1955—2005年间诊断的2 942例尘肺患者有关资料进行了回顾性收集,并采用SPSS10.0软件进行统计分析。结果显示,青海省共有7种尘肺,其中矽肺和煤工尘肺占尘肺总数的93.88%。至2005年底,共有672例已死亡,尘肺病死率为22.84%。尘肺患者死亡年龄集中在40~49岁、50~59岁、60~岁组,占整个死亡总数的92.26%。平均死亡年龄为60.24岁,并且随着年代的推移而延长。尘肺患者平均寿命损失为15年。对死因分析后发现,前3位死因依次为:肺心病、尘肺和肺结核。探讨、分析及研究的结果表明,高原地区尘肺患者的首位死因为肺心病,提示在今后高原地区尘肺病防治工作中应加以重视。  相似文献   
169.
近因原则是商业保险中用于区分保险责任和非保险责任的一个被普遍认可的工作原则,工伤认定是确认是否进行工伤保险金给付的前提。针对目前中国工伤认定相关法律不健全的现状,笔者首次提出在工伤认定有关规定的列举法空白处,使用近因原则的建议。有益于完善工伤认定工作。通过分析我国工伤认定有关规定的历史沿革与现行做法,指出现行工伤认定规定不合理之处,如列举未尽的弹性处理不利于员工、严苛的免责条款不利于雇主、雇员野蛮操作零成本降低社会福利,应用近因原则处理过劳死、未经归类的职业病两个案例,弥补现行工伤认定立法缺陷,实践证明,工伤认定中使用近因原则是可行的、合理的、实用的。  相似文献   
170.
Prenatal diagnosis of Niemann–Pick disease types A and B is routinely accomplished by sphingomyelinase assay. For Niemann–Pick type C disease, demonstration of an abnormal intracellular cholesterol trafficking is a complex procedure, and mutational analysis (NPC1 or NPC2/HE1 gene), whenever feasible, represents a major advance. Copyright © 2002 John Wiley & Sons, Ltd.  相似文献   
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