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The Psychosomatic Symptom Checklist (PSC), a questionnaire assessing psychosomatic symptoms, was administered to two separate samples of college students. For Sample 1 (N=698),the questionnaire was readministered to three separate subsets at intervals of either 1 week (N=143),4 weeks (N=74),or 8 weeks (N=48).Each subset of subjects recompleted the PSC on only one of the three retest intervals. Based on the initial administration an analysis of the normative data revealed a mean total score of 23.7, suggesting a relatively low degree of psychosomatic symptoms in this group. Although total scores decreased slightly over time, test-retest correlations remained high (r>0.80, P<0.0001).Individual item correlations varied and also decreased across time; however, the majority of correlations was greater than r=0.50 throughout. Sample 2 (N=249)completed the PSC, Beck Depression Inventory (BDI), State-Trait Anxiety Inventory (STAI-X), and Rathus Assertiveness Scale (RAS), and intercorrelations were computed between these measures. This analysis revealed little overlap between the psychosomatic complaints assessed by the PSC and other commonly used measures of psychological distress. Finally, a factor analysis revealed one major factor on which all but 2 of the 17 questionnaire items loaded significantly. These results suggest that the PSC is sensitive to psychosomatic distress and remains reliable over time.This reaserch was supported in part by Grants NS-15235 and NS-16891 from NINCDS.  相似文献   
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Using an in vitro assay to measure O6-methylguanine-DNA-methyltransferase (MT) activity in cell extracts from a panel of human-hamster cell hybrids, we were able to locate the human MT gene on chromosome 10. Chinese hamster cells have little or no MT activity and the presence of human chromosome 10 was a necessary condition for MT activity in cell hybrids. In some cell hybrids carrying chromosome 10, however, MT activity was not higher than that of hamster cells. As an explanation for this result, genetic determinants repressing MT expression and/or activity might be present in other human chromosomes carried by MT-negative cell hybrids. Partial hyperploidy of the hamster karyotype, variable activity of the parental human cell lines and changes during subculturing of the cell hybrids might also account for the lack of enzymatic activity in chromosome 10 containing hybrids.  相似文献   
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个体化下肢小腿假肢接受腔设计的生物力学评价技术研究   总被引:3,自引:0,他引:3  
作为传递体重、固定假肢的部件 ,接受腔对于小腿假肢使用的舒适性和方便程度有决定性的作用。本研究建立了基于有限元应力分析的小腿假肢生物力学评价技术平台 ,实现了小腿残端 /接受腔 3D几何建模与信息交互、三维有限元自动建模及应力分析。 3D模型与信息交互的实现基于得到广泛支持的OpenGL技术 ,有限元模型的构建采用了专门针对小腿残端 /接受腔结构特点的自动建模方法 ,通过构建档案数据库系统作为整个系统的操作平台。该技术平台可与现有的CAD/CAM系统相结合 ,为接受腔的个体化设计提供生物力学定量化依据。其临床应用将改善传统的设计流程 ,提高设计效率。同时 ,它也是未来构建接受腔设计专家 /智能系统的基础。  相似文献   
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In gastric carcinomas, including 20 cases of intestinal type and 10 cases of diffuse type, in adenomas with mild to severe dysplasia (20 cases), and in hyperplastic polyps (10 cases), the presence of lactoferrin was investigated by immunohistochemistry. Incomplete or complete intestinal metaplasia or both and normal gastric mucosa were also tested. Preoperative hematocrit and serum iron levels (18 patients) were recorded. An evident reactivity for lactoferrin was encountered in intestinal type carcinomas, adenomas, and incomplete intestinal metaplasia, whereas diffuse-type carcinomas, hyperplastic polyps, and complete intestinal metaplasia were always unstained; mucous neck cells of the antrum and body were also positive for lactoferrin. The results are discussed in relation to the increased requirement of iron by neoplastic cells, although in gastric carcinomas serum iron levels appear to be unrelated to the immunohistochemical presence of lactoferrin.  相似文献   
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Dream recall after sleep interruption in brain-injured patients   总被引:1,自引:0,他引:1  
Nineteen patients with unilateral hemispheric lesions of a vascular or neoplastic nature were studied. Before the onset of disease, these patients had experienced dream recall at least once a week. During hospitalization their dream recall was investigated using a morning diary for 10 consecutive days. During this period, seven patients reported having dreamed, whereas 12 had no dream recall. Subsequently, the patients' sleep was interrupted during both stage 2 NREM and REM sleep. With this method, 11 patients reported having dreamed at least once, whereas eight had no dream recall. Patients with lesions in the temporo-parieto-occipital region had a more frequent loss of dream recall than those with lesions outside this area. The agreement between the results obtained using the diary and those from provoked awakening was significant. The results obtained from compilation of a diary on morning awakening appear sufficiently reliable to reveal the presence or absence of dream recall in patients with focal cerebral lesions in the acute phase of the disease.  相似文献   
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Up to now, we have identified 77 X-linked conditions in which mental retardation is the primary or a major component manifestation. These conditions were subdivided into 2 categories, designated respectively "X-linked mental retardation syndromes" and "Non-specific X-linked mental retardation". Forty genes have been regionally mapped onto the X chromosome. However, in several instances the data were derived from a single family and most lod scores were less than 3.0.  相似文献   
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