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71.
Objective To investigate the value of statistical parametric mapping 5 (SPM5) and its parameter settings in analysis of PET imaging for epilepsy patients. Methods Seventeen epilepsy patients and seventeen controls were scanned with PET. The datns were analyzed using PET and SPM5 with qualitative and semiquantitative analysis, statistical analysis of the percentage (numbers of agent distribution decreasing in focus to brain) for different parameters combinations, which were value adjustment to contral-p and voxels-k. Results There was decreasing of agent distribution at temporal lobe in epilepsy patients detecting with PET; the T/NT of focus to cerebellum was 1.07±0.24, the T/NT of normal tissue in opposite side to cerebellum was 1.27±0.18, there was a significant difference (t=1.87, P<0.05). Dealing with SPM5, there was more significant decreasing of agent in regions 19, 21, 39 of temporal lobe, regions 7, 19, 31, 40, 47 of parietal lobe and occipital lobe in epilepsy patients. With different value of k, the percentage was (27±22)%, (29±24)%, (32±23)%, (35±27)%, (39±31)%respectively, there was not significant difference (F=0.59, P>0.05) ; for different value of p, the percentage was (42±30) %, (29±25) %, (26±21) % respectively, with a significant difference (F=3.60, P<0.05); there was linear regression in value adjustment to contral-p and the percentage(b=-18.24, t=2.57, P<0.05). Conclusions Semiquantitative analysis by SPM5, the setting of value adjustment to contral-p would affect the results, the smaller of value adjustment to contral-p, the better of the result. SPM5 would be more objective and accurate to locate the focuses. 相似文献
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T.G. van Kooten J.M. Schakenraad H.C. van der Mei A. Dekker C.J. Kirkpatrick H.J. Busscher 《Medical engineering & physics》1994,16(6):506-512
In this study, human umbilical vein and human saphenous vein endothelial cells were seeded on glass and exposed to fluid shear in a parallel-plate flow chamber. Cell retention, morphology and migration were studied as a function of shear stress and of adhesion time prior to exposure to shear. Three-hour and 24-h adhesion times gave rise to comparable cell retention values after 2 h of flow for both cell types. Cell retention decreased from 85 to 20% as shear stress increased from 88 to 264 dynes cm−2 (8.8 to 26 Pa). Mean spreading areas decreased after the onset of flow, but subsequently stabilized to plateau values, which were smaller at higher shear stresses. Shape factors increased faster to higher values as cells were exposed to higher shear stresses, without any obvious preference in orientation of the cells with respect to the direction of flow. Migration was unidirectional with flow and linear with time. Migration was faster for cells which had adhered for 24 h than for cells which had adhered for 3 h and was accompanied by the presence of fibrillar structures left behind on the surface upstream of migrating cells. It is concluded that after 3 h adhesion to glass, cells have adhered with an adhesion strength that does not substantially increase during the next 21 h. However, during this time changes in cell-substratum interactions seem to occur judging by the differences in, e.g., migration rates. 相似文献
76.
佛山市城区室内装修污染特征初探 总被引:8,自引:0,他引:8
目的 为了解佛山市室内装修空气污染状况,通过对佛山市室内装修污染物进行调查,掌握室内装修污染的一些基本特征并提出控制措施。方法 根据卫生部《室内空气质量卫生规范》以及《室内空气污染物的检验方法》方案,调查采用了问卷调查和现场检测的方法。结果 佛山市室内装修空气污染物主要为甲醛,苯,总挥发性有机物(TVOC),超标率分别为86%,36%,23%。结论 目前佛山市城区室内装修污染物的特征为:有机污染较无机污染严重,室内甲醛污染严重,苯次之而氢污染相对较轻,室内空气苯污染车辆、居室高于办公室,甲醛污染居室,办公室高于车辆。 相似文献
77.
Through a critical study of herbalogy, it is concluded that the mature seeds of Alpinia zermubet were used as caodoukou in ancient times. The original plant of Yutao recorded in Zhiwu Mingshi Tukao may be the species of Alpinia katsumadai. Baidukou used in ancient times may be the seeds of Alpinia katsumadai found in the south of China, or Amomum compactum and Am. kravanh imported from foreign countries. 相似文献
78.
控制性降压在临床麻醉中的应用进展 总被引:6,自引:0,他引:6
控制性低血压是指在某些手术麻醉期间,用药物等方法降低血压,以达到减少手术野出血,便于手术操作的一种方法,通常采用血管扩张剂,钙通道阻断剂及麻醉来控制血压,现就这一领域的研究进展作一综述。 相似文献
79.
Previous reports in the literature have described correlation of increasing repeat length with severity of the phenotype, in Kennedy syndrome. We describe male siblings with different repeat lengths, with lack of expression of the phenotype in the sibling with the longer repeat length. The phenotype was identical to motor neurone disease. There is variability of expression in Kennedy syndrome and repeat length even in siblings cannot be taken as a conclusive indicator of severity. CAG repeat length cannot be used to predict the natural history of Kennedy disease. The diagnosis of Kennedy syndrome should be considered in male patients presenting with atypical motor neurone disease. 相似文献
80.
笔者提出了对Reed-Frost模型的学术评论,并新建了一种Reed-Frost模型的改进模型。该改进模型全面考虑了隐性感染者的产生、传染作用及向免疫者的转化。应用这个模型,模拟了NewEngland的麻疹流行和中国上海市某保育院的水痘流行,结果颇为理想。该模型包括了基本的流行要因,故能用以解释流行过程,并可帮助流行病学工作者理解隐性感染在传染病流行过程中的作用。 相似文献