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111.
Since Samuel Orton's (1937) assertion that dyslexia reflects abnormal brain organization, the relationship of learning disabilities to brain dysfunction has been the topic of considerable debate. Recently, learning-disabled individuals have been studied in conjunction with those known to have neurological dysfunction, in a search for common subtypes. In the present study, a population of 177 children, ages 9-0 to 14-0, were assessed on an augmented version of the Children's Halstead-Reitan Battery. One hundred twenty-nine Ss were learning-disabled, 37 of whom also had verified brain damage. The remaining 48 children had neither learning disabilities nor evidence of brain damage. Patterns of neuropsychological performance were determined using Tryon's clustering methods. The procedure yielded six subject clusters: (A) and (B)—children with low general intellectual ability; (C) children who are clumsy and lethargic; (D) children with language dysfunction; (E) children with faulty spatial orientation; and (F) children with no detectable neuropsychological deficits. These clusters were similar to those identified by investigators who have used other subject-clustering methods. Brain-damaged individuals were more prevalent in some clusters (e.g., A and B) than in others (e.g., E and F), and substantial numbers of learning disabled subjects were also found in clusters where brain-damaged individuals tended to cluster, indicating similar neuropsychological profiles. The cluster structure was validated by comparison with subtypes identified by other investigators, as well as by tests of association between clusters with exogenous factors (e.g., history of prematurity; seizures).  相似文献   
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113.
The validity of a hinged constant force probe (0.25 N) was compared with that of a similar but immobilised instrument, using the same interchangeable tip for both (0.64 mm diameter; 2 mm divisions). 60 sites were measured on teeth which were extracted subsequently, in patients with untreated periodontal disease, and the connective tissue attachment level was used as validity criterion. The clinical measurements of both probes correlated well with each other, but they differed significantly from the post-extraction connective tissue attachment level measurements, indicating a point 1.2 mm coronally to this, on average. A companion investigation of intra-operator probing depth reproducibility with the 2 probes, was undertaken in 14 patients, at 2 visits separated by 1 week in each case. All patients had untreated periodontal disease. A difference between probes was found at the first visit, but not at the second; the immobilised probe showed a difference between visits, reducing mean probing depth slightly at the second; when the immobilised probe was used first, there was a difference between probes. Further analysis of the results indicated that there was greatest agreement between probes when the constant force probe had been used before the immobilised probe at the second visit. The results suggested that these probes indicated a point above the connective tissue attachment level, related to pocket morphology, and that there was a moderate learning effect due to operator use of the constant force probe, which modified use of the immobilised probe.  相似文献   
114.
用“点值法”对健康工人473例[轻体力劳动工人(简称轻工)248例,重体力劳动工人(简称重工)225例]。作了流量一容积曲线和常规通气功能检查。结果表明:重工男女在40岁以后其高肺容积流量下降,30岁以后低肺容积流量上升,而且这些改变有随年龄增长而更加明显的倾向;轻工仅有个别年龄组的低肺容积流量上升。对7名健康坐位工作者模拟劳动的前倾姿势作多次通气功能检查,亦有明显高肺容积流量下降和低肺容积流量上升的现象,这一事实提示波速学说亦可应用于颈和躯干前倾进行重体力劳动工人的通气行为。  相似文献   
115.
在排除电场干扰伪迹后,耳蜗微音电位响应曲线可以作为反映近全耳蜗电生理功能的一项测试指标。能方便而迅速地完成测试,结果可靠。船舶噪声暴露后,显示耳蜗损伤频带主要在3.15~8kHz范围。这与人噪声性听力损失的特征非常类似。  相似文献   
116.
本文主要分析在近几年的数学高考题中导数方法的应用.阐述了利用导数知识研究函数的单调区间、最大值最小值等问题的基本方法,以及导数方法为解决某些不等式的证明、数列求和等问题提供了捷径.同时导数方法在研究曲线的切线方面更有广泛的应用,也体现了数形结合的重要思想.  相似文献   
117.
118.
包甲素合成类似物的过筛试验   总被引:7,自引:0,他引:7  
本文采用豚鼠离体纵长肌累积剂量-效应曲线法,求解离常数(KD)及最大效应(Emax)值,以氨甲酰胆碱为标准药,对14个莨菪烷类化合物进行比较,结果表明:6β-乙酰氧基去甲莨菪烷,3α-对甲苯甲酰氧基-6β-乙酰氧基莨菪烷及3α,6β-二乙酰氧基莨菪烷三化合物有明显的M受体激动作用。其构-效关系提示:6β-乙酰氧基是M激动作用的关健结构,N位上的CH_3能削弱这一作用。  相似文献   
119.
Remodeling Adult Nursing   总被引:1,自引:0,他引:1  
This article describes a nursing education experience in which a critical thinking approach was planned and implemented. Background discussion on critical thinking concepts and related research provides a foundation for presentation of the Mackie teaching model. The model uses a community-based, family-centered scenario as the basis for developing problemfocused nursing intervention skills from a holistic viewpoint. Role expectations of students and faculty are outlined, and related implementation difficulties, together with their resolution strategies, are described. Evaluation methods and outcomes are reviewed in the conclusion.  相似文献   
120.
以问题为中心的病案教学法在临床核医学中的实践   总被引:8,自引:0,他引:8  
目的 设计以问题为中心的病案小组讨论教学法,在临床核医学核素治疗见习的教学实践中进行验证和评价。方法 总结近几年在临床核医学见习带教中的问题与缺陷;以病案引入问题,教师引导,进行小组讨论;评价教学效果。结果 临床核医学及其教学具有不同于其它临床学科的鲜明特点和规律;经改革的教案,收到学生和教师的良好反馈。结论 以问题为中心的病案小组讨论教学法,切合临床核医学见习实际,有效可行。  相似文献   
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