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41.
Sixty Sprague-Dawley rats were pair-fed one of three nutritionally identical diets. One diet contained “low-fiber” (3.8% crude fiber); the others contained “high fiber” (28.7% crude fiber) composed of either cellulose or lignin. Although both “high fiber” diets had similar stool bulking effects, only the cellulose diet was associated with a reduction in 1,2-dimethylhydrazine (DMH)-induced colon neoplasms. The cellulose diet was also associated with distinct changes in the gut bacterial profile and with a lowered serum cholesterol. © 1993 Wiley-Liss, Inc.  相似文献   
42.
Muscle fiber typing and in vitro contracture tests were performed in 59 patients investigated for susceptibility to malignant hyperthermia (MH). Eighteen patients were found to be susceptible to MH. There was no difference in age or fiber type distribution between MH susceptible and non-susceptible patients. No correlation was found between age and fiber type distribution. Separate analyses for each diagnostic group revealed no relationship between age or fiber type distribution and response to halothane or caffeine. When all caffeine results were pooled, however, there was a significant effect of age on the caffeine specific concentration (the concentration eliciting a contracture of 1 g), but not on the caffeine threshold concentration (the minimal concentration eliciting an increase in tension). It is concluded that age and fiber type distribution have no influence on MH diagnosis, if the protocol of the European MH Group for evaluation of susceptibility to MH is followed.  相似文献   
43.
通过对10例小儿及23例成年人的喉内肌进行的myosin-ATPase等染色观察,得到小儿和成人各喉内肌不同的肌纤维构成比。成人PCAⅠ型纤维最多,LCA、INA及CT次之,TA最少。小儿的各喉内肌也有类似比例。表明不论小儿或成人,PCA均具有较强的抗疲劳性,适应呼吸作用的需要;TA具有较快的收缩速度,以适应发声及呼吸道保护作用。从纤维构成上看,小儿与成人相比,各喉内肌Ⅰ型纤维较为匮乏,表明小儿的喉在发声及呼吸道保护等功能方面尚不够完善。  相似文献   
44.
玻璃纤维增强复合树脂在总义齿基托中的应用   总被引:1,自引:0,他引:1  
目的:增强总义齿基托的机械性能,提高总义齿的基托抗折裂能力。方法:对E-玻璃纤维用KH-550处理剂进行表面处理后,加入总义齿基托中,制成玻璃纤维增强复合树脂。结果:经过1年的临床观察后复诊,没有发现裂纹。结论:玻璃纤维增强得合树脂可以有效地增强总义齿基托的机械性能。  相似文献   
45.
孙滢滢  张少锋  周冰  孔亮 《中国美容医学》2006,15(2):173-174,i0007
目的:利用Matlab和Ansysworkbench软件辅助建立桩核冠三维有限元模型。方法:应用薄层CT技术,获取建模所需二维影像45张(层厚0.5mm,无间隔),利用Matlab软件编程读取图像边界数据,导入Ansys三维有限元专用软件,在Ansysworkbench环境中三维重组模型,同时进行模型单元划分和力学检测。结果:建立包含桩核、冠修复体、牙根、粘固剂、牙胶尖、牙周膜、松质骨和皮质骨的三维有限元模型。结论:利用Matlab软件和Ansysworkbench软件辅助建模,提高了建模的精度、速度和灵活性,为牙颌组织三维有限元建模提供了新的方法。  相似文献   
46.
Cell culture-based influenza vaccine manufacturing is of growing importance. Depending on virus strains, differences in infection dynamics, virus-induced apoptosis, cell lysis and virus yields are observed. Comparatively little is known concerning details of virus–host cell interaction on a cellular level and virus spreading in a population of cells in bioreactors. In this study, the infection of MDCK cells with different influenza A virus strains in lab-scale microcarrier culture was investigated by flow cytometry. Together with the infection status of cells, virus-induced apoptosis was monitored. A mathematical model has been formulated to describe changes in the concentration of uninfected and infected adherent cells, dynamics of virus particle release (infectious virions, hemagglutinin content), and the time course of the percentage composition of the cell population.  相似文献   
47.
Propriospinal myoclonus (PSM) is a rare movement disorder characterized by involuntary spinal-generated muscular jerks that spread rostrally and caudally to other spinally innervated muscles. Most patients have no clear etiology, and conventional MRI of the spinal cord is generally normal. Here we report the use of magnetic resonance diffusion tensor imaging (DTI) and fiber tracking to detect tract-specific abnormalities in a patient with propriospinal myoclonus. As the patient had the fragile-X premutation and antithyroid antibodies, spinal cord DTI abnormalities may be related to these conditions. Tract-specific analysis may provide new insights into the pathophysiology of propriospinal myoclonus.  相似文献   
48.
This paper considers the immediate post‐traumatic reactions of rescue personnel who were exposed to the Hilton Hotel bombing in Sinai. The entire rescue personnel (n = 26) were assessed and separated into two groups on the basis of previous exposure to the same type of trauma. The results suggest that among rescue personnel, those with previous exposure had a lower level of post‐traumatic symptoms than those who were being exposed for the first time. This supports the hypothesis that previous exposure to the same type of trauma has an immunizing effect for subsequent same type of traumatic event among rescue personnel. Copyright © 2005 John Wiley & Sons, Ltd.  相似文献   
49.
The PK and PS scales of the MMPI‐2 were developed to index the degree of post‐traumatic stress disorder (PTSD). These scales were applied to a sample of 254 mostly male sworn and civilian law enforcement employees from four police agencies. Participants also completed surveys measuring their perceived levels of job stress, their use of a set of coping strategies, and their performance on measures of five global personality domains. The two PTSD scales appeared to have good internal structures and relatively high reliabilities. Employees at greater risk for PTSD reported higher levels of work‐related stress, seemed to use more maladaptive coping strategies, were more neurotic, and tended to be less extraverted, agreeable, and conscientious. Copyright © 2004 John Wiley & Sons, Ltd.  相似文献   
50.
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