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91.
92.
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   
93.
目的:观察通气时碱石灰尘埃向呼吸环路中的排放及被呼吸道阻留的情况。方法:麻醉机环路连接集尘袋及筛装新碱石灰。JT库尔特颗粒计数仪动态测定排尘量。其颗粒测量范围为1~125μm3,通气10分后测定呼吸环路加集尘袋内的尘埃量即为总尘量,收取称干重得尘埃分散度。通过对Nar-comed、Drager、Sular808和103麻醉机行上述测量后,另以前者(N机)为例,其环路按相应处理分干燥、湿化和过滤三组,志愿者模拟通气10分测定环路含尘量后与总尘量差得气管肺的阻留量。结果:四种麻醉机环路内碱石灰尘埃的分散度达13mg/m3以上。尘埃排放量与通气时间呈正比(r=0.95,P<0.01)。N机干燥组中总排尘量的半数以上被气管肺阻留。湿化组该阻留量明显下降(P<0.05),而过滤组环路内总排尘量和气管肺阻流量下降更为显著(P<0.01)。结论:使用新碱石灰通气时,麻醉机环路内存在严重的尘埃污染,环路内湿化有一定的防尘作用,但以滤过处理效佳。  相似文献   
94.
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   
95.
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   
96.
The purpose of this study was to compare the attitudes toward basic sciences of students in a preclinical problem-based curriculum and a conventional lecture-based curriculum at the end of their second year of medical school. The results showed that the PBL class had more positive attitudes toward basic sciences than students in the conventional class. These results may reflect a learning environment where students meet many scientist role models as teachers and where basic science is learnt in the context of clinical problems.  相似文献   
97.
Thirty-four social drinkers who had referred themselves to the Regional Brain Damage Unit for assessment of the effects of drinking alcohol were compared with 42 volunteer control subjects of equivalent age but with low alcohol intake, using two 'learning' tests — the Rey Auditory Verbal Learning Test (RAVLT) and the Austin Button Maze. The Maze Test gave no evidence of disorder, but the two groups were significantly different on the RAVLT. No abnormalities in standard cognitive tests were apparent. These results suggest that a deficit in learning ability may be an early feature of the brain dysfunction associated with excessive alcohol consumption.  相似文献   
98.
岛津数字胃肠机IF OVER故障产生的原理及维修   总被引:1,自引:0,他引:1  
雷烈 《医疗设备信息》2007,22(6):113-113
分析了岛津3200数字胃肠机IFOVER故障产生的原因,并结合实际故障现象,具体介绍了排除方法。  相似文献   
99.
目的探讨下颌骨侧位摄影分别采用一倾斜角度为α的垫板及未采用时,X线中心线倾斜角度各为β、γ之间的关系,为更简捷地拍好下颌骨提供理论参数和实践依据。方法立足于教科书,运用X线摄影原则与数学几何原理进行推理演绎。结果二者之间存在着可替换的关系,即γ=α+β,可以大胆地去除垫板进行直接拍摄。结论不用垫板,只需通过增大X线中心线倾斜角度的方法,同样也能拍摄出一张好照片,且可操作性强,简便易行,实际使用价值更大。  相似文献   
100.
Vocational training is a key element of professional development in general practice. Learner-centred approaches to teaching bring a need for greater understanding of the individual learning styles and preferences of trainees. This paper reports the findings of a pilot study undertaken to determine factors that may influence learning among general practice trainees. A questionnaire survey of 261 trainees in six regions in the UK was carried out to explore attitudes to a series of themes identified in semi-structured interviews with trainees at the end of their training. Six distinct subscales were identified using principal components analysis. These are named 'Learning from Patients', 'Openness to Criticism', 'Negative Attitudes', 'Desire for Clear Guidelines', 'Peer Support', and 'Academic Approach'. Males scored significantly higher on 'Academic Approach' (   P < 0.05  ). Each of the subscales reflects themes that permeate the atmosphere of general pratice training. Further work is required to establish relationships between the subscales and the outcomes of learning and to explore the implications for continuing professional development. The questionnaire is an instrument that may prove useful in the future investigation of learning in general practice.  相似文献   
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