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101.
目的:为探讨早期尘肺病患者肺功能评定及其劳动能力鉴定中的应用。方法:本文做了Ⅰ期77例尘肺病人通过临床表现即呼吸困难的判定、高仟伏X线胸片检查、肺功能测定等检查进行了肺功能损伤分级及劳动能力鉴定。结果:矽肺组的肺功能较铸工尘肺明显下降。吸烟组肺功能测定结果低于不吸烟者,尤其是矽肺组,两组有显著性差异(P〈0.05)。77例尘肺病例中,44例尘肺病人为轻度损伤,其中矽肺33例,铸工尘肺11例,可定为伤残六级,33例尘肺肺功能测定正常,全部为铸工尘肺,伤残等级为七级。结论:我们测定的四项指标中有2项或2项以上指标有改变,并结合临床结果一致时,可诊断为该级别肺功能损伤较为合理。 相似文献
102.
103.
图片学习测验在识别老年人轻微认知功能损害中的作用 总被引:6,自引:2,他引:4
目的 分析图片学习测验在识别老年人轻微认知功能损害 (MCI)中的作用。方法 选择符合MCI诊断标准的老年人 4 8例与正常对照组 5 6名完成图片学习测验、简易智能状态检查、听觉词语学习测验及多种非记忆测验。结果 图片学习测验的 3个记忆指标 (图片短时记忆、延迟记忆和学习记忆 )在MCI与正常对照组之间有非常显著的差异。已经给出这三个图片记忆指标区分MCI与正常老年人的划界分、敏感性和特异性。结论 图片记忆操作简便、信度和效度好 ,可以作为临床医师筛选MCI的有效工具 相似文献
104.
Paolo Calabresi Emesto Fedele Antonio Pisani Giovanni Fontana Nicola B. Mercuri Giorgio Bernardi Maurizio Raiteri 《The European journal of neuroscience》1995,7(9):1889-1894
Using a corticostriatal slice preparation, we have recently shown that tetanic stimulation of the corticostriatal pathway produces long-term depression (LTD) of striatal excitatory synaptic transmission. In the present study we have analysed the relationship between LTD and the striatal release of different endogenous transmitters. Samples of perfusate were collected via a small cannula placed just above the surface of the striatal slice close to the recording electrode, and were analysed by HPLC. The high-frequency stimulation (100 Hz, three trains, 3 s duration, 20 s intervals) used to induce LTD caused a significant but transient increase in the release of both excitatory (aspartate and glutamate) and inhibitory (glycine and GABA) amino acid transmitters. Tetanic stimulation also produced a significant, but transient increase in the release of endogenous dopamine. We conclude that the tetanic stimulation of the corticostriatal pathway is able to induce a large but transient release of excitatory amino acids and of dopamine, whose participation in the induction of striatal LTD has been demonstrated previously. Moreover, the maintenance of this form of synaptic plasticity does not seem to require a sustained change in transmitter release. 相似文献
105.
Functional Anatomy of Visuomotor Skill Learning in Human Subjects Examined with Positron Emission Tomography 总被引:9,自引:0,他引:9
Julien Doyon Adrian M. Owen Michael Petrides Viviane Sziklas Alan C. Evans 《The European journal of neuroscience》1996,8(4):637-648
The present study was designed to examine patterns of regional cerebral blood flow (CBF) associated with the learning of a repeated visuomotor sequence both in the early and late phases of the acquisition process. In addition, changes in blood flow related to the implicit versus explicit aspects of learning such a skill were investigated. Fourteen normal control subjects were scanned while performing the task (i) in both early and advanced learning stages of the visuomotor sequence; (ii) after having acquired explicit knowledge of the sequences; and (iii) in two control conditions (perceptual and random sequence). Subtraction of the random condition from the highly learned condition revealed specific areas of activity in the right ventral striatum and dentate nucleus of the cerebellum. Blood flow changes in the right hemisphere were also seen in the medial posterior parietal and prestriate regions, as well as in the anterior cingulate cortex. Finally, once the subjects had acquired explicit knowledge of the embedded sequence that was presented in the highly learned condition, increased CBF activity was observed only in the mid-ventrolateral frontal area in the right hemisphere. These findings confirm that both the striatum and the cerebellum are involved in the implicit acquisition of a visuomotor skill, especially in the advanced stages of the learning process, and furthermore that the ventrolateral prefrontal cortex contributes preferentially to the declarative aspect of this task. 相似文献
106.
107.
Thomas A. Blakely Jr. Francis M. Crinella Todd D. Fisher Lorraine Champaigne Frances W. Beck 《Journal of developmental and physical disabilities》1994,6(1):1-22
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
108.
109.
Validity of a hinged constant force probe and a similar, immobilised probe in untreated periodontal disease 总被引:2,自引:0,他引:2
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
110.
There is considerable evidence that sex differences in spatial ability exist in adults, with males outperforming females at every age after puberty. It is difficult, however, to find sex differences in children younger than 13. This is due in part to the lack of adequate measures of spatial ability for use with children. We report the use of spatial tests for children that are similar to those that have shown large sex differences in adults and may be measuring ability comparable to adult spatial ability. Four tests of mental rotation and spatial visualization were given to two samples of children. The first sample consisted of 81 children (39 males and 42 females) aged 9 to 12 years. The second sample consisted of 42 children (21 males and 21 females) aged 9 to 13 years. Sex differences of .4–.6 standard deviations were found on three tests in both samples. These results indicate that sex differences in spatial ability can be found in preadolescents if appropriate tests are used. Measurement of these abilities in children facilitates the investigation of possible biological and sociocultural contributors to the sex differences in spatial ability.This study was supported by National Institutes of Health Grant HD19644 and NIH Biomedical Research Support Grant S07 RR05366-24. 相似文献