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51.
应用最小二乘法拟合得到寰枢椎侧块关节运动轨迹方程 ,左半部是 :S(x) =-2 3 .2 42 9-8.663 1x-0 .45 91x2 ;右半部是 :S(x) =-19.683 8+ 7.15 5 4x-0 .3 5 2 6x2 。  相似文献   
52.
目的:探讨腰椎形态结构变化对峡部裂性滑脱及小关节退变的作用和意义。方法:采用改良的“非种子区域分割方法”及非平行“最佳切割平面”等一系列新型计算机辅助设计(CAD)方法精确建立包括椎间盘高度、腰椎小关节角、椎间盘前凸角改变的L4~L5活动节段有限元模型;在2700N轴向压缩载荷条件下,分别对各有限元模型的峡部、小关节应力、小关节接触力以及椎间盘负载进行测试。结果:压缩载荷下,腰椎活动节段峡部、小关节等效应力及小关节接触力随椎间盘高度的减小而减小,随小关节角的增大而增加,随椎间盘前凸角的增加而减小。结论:椎间盘高度、腰椎小关节角、椎间盘前凸角等形态结构变化对腰椎节段有限元模型的峡部、小关节应力及小关节接触力有明显的影响。提示腰椎峡部应力性骨折及小关节退变的发生与椎间盘高度、腰椎小关节角、椎间盘前凸角等解剖形态因素有关。  相似文献   
53.
PURPOSE: The purpose of this study was to measure spectrophotometrically the color stability of pigmented A-2186 silicone maxillofacial elastomer with 10% by volume of titanium white dry earth opacifier before and after exposure to microwave energy over a simulated 1.5-year period of microwave sterilization. Materials AND METHODS: A-2186 silicone elastomer opacified with titanium white dry earth pigment, pigmented with 5 cosmetic dry earth pigment colors [no pigment (control) group (Pc), red (Pr), yellow ochre (Py), burnt sienna (Po), and a mixture of Pr + Py + Po color group (P3)], was used in this study. Each of the 5 experimental groups consisted of 5 specimens. All specimens were placed in a 250 ml glass beaker filled with 150 ml of water (replenished for each microwave exposure). An exposure of 6 minutes was used 18 times (simulating 1.5 years of microwave sterilization with one 6 minute exposure monthly). Reflectance values were measured by spectrophotometer. Three- and two-way analyses of variance with repeated measures were performed for the color difference (DeltaE*) with the factors of group/color/months, and group/months, respectively. Means were compared by Tukey Honest Significant Difference (HSD) multiple range test calculated at the 0.05 level of significance using SPSS. RESULTS: The trained human eye can detect color changes (DeltaE*) greater than 1.0. Most DeltaE* values of the red pigment group at all intervals and the mixed pigment group at 15- and 18- month intervals increased significantly greater than 1.0 (p < 0.001) compared with the control group. Yellow and burnt sienna groups remained the most color stable over time with DeltaE* values below 0.35. CONCLUSIONS: Lack of color stability of red dry earth pigmented A-2186 silicone maxillofacial elastomers was clinically significant after 12-month exposure to microwave energy as compared with yellow, burnt sienna, and opacified A-2186 dry earth pigments.  相似文献   
54.
用5只猫于左侧颈部食管壁内注入 HRP 溶液,通过 HRP 逆行追踪法研究颈部食管的交感神经支配,结果表明:1.长轴突型交感节前神经元直接分布到食管壁内,其标记细胞位于双侧脊髓的胸1~3节段,以胸2节段最多(占标记细胞总数的66.45%),注射侧占优势。标记细胞主要位于中间带外侧核(约占95.02%),其次为侧索、中介核、前角腹后外侧核。其细胞形态不一,以中小型细胞为主(占标记细胞总数的90.4%)。2.支配颈部食管的交感节后神经元主要位于星状神经节(约占61.99%),余者位于双侧颈前、中和2~5胸交感节内、以小细胞最多。  相似文献   
55.
本文提出的“差式氧化数法”特别适用于有机化学反应方程式的平衡。在未平衡方程式之前即可直接求出有机物的氧化还原当量,然后再平衡方程式。较以前先平衡方程式,再间接计算氧化还原当量的方法简便,快速,易掌握。  相似文献   
56.
引入PDCA循环规范医疗废物管理   总被引:2,自引:0,他引:2  
目的采用PDCA循环法,规范医院医疗废物管理。方法通过计划、实施、检查、处理4个阶段具体实施。结果医疗废物要达到规范化管理,建立有效的组织管理体系,制定切实可行的规章制度是重要保证;加强培训与宣传教育,提高全员管理意识是重要环节;完善医疗废物处置过程中的配套设施是重要基础;制定管理质量标准认真督促检查考核是重要手段。结论PDCA循环法是加强完善医疗废物管理的一种科学的管理方式。  相似文献   
57.
本文介绍使用氨气敏电极,采用标准曲线法简便、快速、准确测定血氨的方法。取空腹血1ml,用1M HClO_4沉淀蛋白,以0.1M NH_4Cl—0.6MNa_2SO_4作内充液,碱化后的上清液可在2~3min内测试完毕。40例正常成人血氨的测定结果:■=31.4μmol/L N;S=6.4μmol/L N;■±2S(正常值范围)为18.6~44.2μmol/L N。10份血样的平均回收率为100.4%。该法用血少、简便、快速;结果较稳定、准确,适用于临床检验。  相似文献   
58.
Objectives To analyze the relationship between lateral displacement of the mandible and scoliosis. Methods From April 2002 through July 2003, we examined posteroanterior cephalometric radiographs and chest X-rays from 85 patients with jaw deformities and a control group of 20 patients with no jaw deformities. To measure the lateral shift of the mandible, we drew a horizontal baseline (X axis) on the cephalogram connecting the intersection of the external margins of the orbits and the most lateral points of the greater wings of the sphenoid. A vertical baseline (Y axis) was then marked perpendicular to the X axis, intersecting the ethmoid crista galli. Then, we measured the lateral displacement of the mandibular mentum from the Y axis. Displacement to the right was designated positive; that to the left was designated negative. Cobb's method was used to measure scoliosis curves on chest X-rays; the direction of the curve was designated similarly. Results Of the 85 patients with jaw deformity, 23 (27.1%) had a Cobb angle exceeding 10°. None of the control group had scoliosis exceeding 10°. No correlation was found between the direction of mandibular displacement and the direction of scoliosis. Conclusion This study suggests a relationship between jaw deformities and scoliosis, as scoliosis was found in 27.1% of the patients with a main complaint of jaw deformity.  相似文献   
59.
Introduction and Aims. Different self‐report methods tend to produce different estimates of alcohol consumption. The present study compares differences in rates and risk levels based on responses to a modified version of the Daily Drinking Questionnaire (m‐DDQ) and quantity‐frequency (QF) questions. Design and Methods. The sample comprised 2082 university students, 61% of whom were female and 39% male with a mean age of 23.5 years. An email containing an online link to a brief six‐question survey was emailed to students enrolled in participating faculties at the University of Wollongong, Australia. Current drinkers completed m‐DDQ and QF questions about alcohol consumption. Results. QF methods identified significantly lower estimates of consumption (Mean = 9.15, SD = 12.51) compared with m‐DDQ (Mean = 13.06, SD = 14.07). Allocation to risk categories based on the Australian Alcohol Guidelines were conducted for both the m‐DDQ and QF methods. Almost twice as many students were found to be drinking at levels considered risky using the m‐DDQ method compared with QF. In addition, the relative rank order of participants varied significantly between the two methods. Discussion and Conclusions. The m‐DDQ method identified higher rates of drinking and categorised almost twice as many individuals into risky categories of drinking compared with QF. Such variations have major implications for identification of risk groups in health promotion or prevention programs.[Utpala‐Kumar R, Deane FP. Rates of alcohol consumption and risk status among Australian university students vary by assessment questions. Drug Alcohol Rev 2009]  相似文献   
60.
羊耳菊水提取物体外抑菌活性研究   总被引:3,自引:0,他引:3  
目的 探讨羊耳菊不同器官水提取物的体外抑菌活性.方法 以金黄色葡萄球菌、铜绿假单胞菌、白色念珠菌等10种微生物为试验菌株,采用药敏纸片扩散法、试管二倍稀释法,对羊耳菊水提取物进行抑菌试验.结果 羊耳菊全株各器官都具有较强的抑菌作用,其中根对10种供试菌种都有抑制作用,抑制范围最广;茎对9种供试菌种有抑制作用,叶对8种供试菌种有抑制作用.羊耳菊各器官对金黄色葡萄球菌与铜绿假单胞菌的抑制作用最强.羊耳菊根、茎、叶对金黄色葡萄球菌的MIC值分别为15.63,62.5,62.5 mg/ml,而其抑菌圈直径分别为14.3,13.8,13.5 mm;羊耳菊根,茎,叶对铜绿假单胞菌的MIC值分别为15.63,31.25,62.5 mg/ml,其抑菌圈直径分别为15.8,15.5,14.0 mm.结论 羊耳菊水提取物体外试验证实了该民间药物具有抗菌活性,也表明了羊耳菊是一种有开发潜力的新抗菌药物资源.  相似文献   
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