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11.
Finite element analysis of the effects of thermal obturation in maxillary canine teeth. 总被引:1,自引:0,他引:1
Ozgür Er Sis Darendeliler Yaman Muvaffak Hasan 《Oral surgery, oral medicine, oral pathology, oral radiology, and endodontics》2007,104(2):277-286
OBJECTIVE: The purpose of the present study was to determine the distribution and level of temperature, in a model of a maxillary canine, the surrounding periodontal tissues, and the bones, during a System B heat obturation technique simulation. STUDY DESIGN: The temperature distribution was determined by using a three-dimensional finite element analysis. The tooth was assumed to have undergone an endodontic treatment before the application. Heat applications of 200 degrees C and 100 degrees C were considered. RESULTS: By using the virtual model and the simulation technique, the maximum temperature in the periodontal ligament was found to be 43.5 degrees C. CONCLUSIONS: Within the assumptions and the limitations of the study, it was determined that the simulation of System B technique created no potentially harmful levels of temperature throughout the maxillary canine model. 相似文献
12.
N N Trapeznikov V A Gorbunova L A Er?mina P A Siniukov E E Kovalevski? 《Voprosy onkologii》1987,33(7):65-74
The effectiveness of cis-diammine-dichloroplatinum (cisplatinum, platidiam, DDP) alone or as a component of combined treatment was evaluated in 85 patients with osteogenic sarcoma. The said drugs were used as adjuvants following radical surgery (group I-18 cases), in combined treatment of solitary and single lung metastases (group 2-7 cases) and in 60 patients with advanced tumors (group 3). An analysis of long-term results showed response in 30.8% in group 3. In group 2, application of chemotherapy plus surgery was followed by remissions of 2-46+-month duration (mean-13.9 months). In group I, 78.7% are expected to survive metastasis-free more than 12 months. Toxicity was moderate, with nausea and vomiting (87.1%), myelosuppression (52.8%), nephrotoxicity (48.6%) and alopecia (75.7%) being the most common side-effects. 相似文献
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Chapiro E Feldmann D Denoyelle F Sternberg D Jardel C Eliot MM Bouccara D Weil D Garabédian EN Couderc R Petit C Marlin S 《European journal of human genetics : EJHG》2002,10(12):851-856
Hearing impairment is the most frequent sensory defect in children, with a genetic basis in about 50% of cases. Several point mutations and deletions in mitochondrial DNA (mtDNA) have been identified in non-syndromic sensorineural hearing loss (NSSNHL). Beside the frequent A1555G mutation, a number of mutations in tRNAs have been reported recently, but their incidence remains unknown. We identified the T7511C mutation in the tRNASer(UCN) gene in two French families with isolated deafness. Maternal transmission was obvious in both. The 15 patients with hearing impairment exhibited a variable disease phenotype in terms of onset, severity, and progression. T7511C was present in all the patients screened. Homoplasmic and heteroplasmic levels were observed and did not correlate with the severity of the disease. T7511C was also present in 12 hearing offspring of the oldest deaf mothers, confirming the existence of modulatory factors. Our data suggest that this mtDNA mutation should be screened for in all cases of familial NSSNHL compatible with maternal transmission. 相似文献
15.
To date, research involving functional neuroimaging of typical and atypical development has depended on several assumptions about the postnatal maturation of the brain. We consider evidence from multiple levels of analysis that brings into question these underlying assumptions and advance an alternative view. This alternative view, based on an "interactive specialization" approach to postnatal brain development, indicates that there is a need to: obtain data from early in development; focus more on differences in interregional interactions rather than searching for localized, discrete lesions; examine the temporal dynamics of neural processing; and move away from deficits to image tasks in which atypical participants perform as well as typically developing participants. 相似文献
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Özışık Pınar Akdemir Özdener Kubilay Murat Ural Berkan Er Uygur Savaş Ali 《Zeitschrift fur Gesundheitswissenschaften》2022,30(6):1431-1440
Journal of Public Health - Because an increasing number of patients travel internationally to seek medical care, Turkey offers comprehensive and outstanding services under extraordinary conditions... 相似文献
17.
目的 评价罗哌卡因用于下腹部手术后镇痛的有效性和不良反应。方法 6 0例择期下腹部手术患者 ,随机分为两组 ,第Ⅰ组为罗哌卡因复合PCA吗啡治疗组 ,第Ⅱ组为安慰剂复合PCA吗啡组。观察罗哌卡因镇痛效果及对运动神经阻滞的影响 ,对比两组的血液动力学变化、吗啡用量和不良反应。结果 罗哌卡因复合PCA吗啡治疗组的术后疼痛评分及不良反应明显低于安慰剂复合PCA吗啡组 ,且第Ⅰ组的吗啡用量明显低于安慰剂组。结论 0 2 %罗哌卡因复合PCA吗啡可安全有效地应用于下腹部术后的镇痛。 相似文献
18.
犬胸部爆炸伤后海水浸泡的实验模型建立及早期救治结果分析 总被引:2,自引:1,他引:1
目的:建立犬海水浸泡胸部爆炸伤实验模型,探讨早期救治结果。方法:20只成年杂犬随机分为爆炸伤组(n=10)和锐器伤组(n=10)。两组动物均于致伤后浸泡在人工配制的海水中25min,而后打捞出海水环境后予以紧急救治。实验中全程监血液动力学呼吸系统和动脉血气变化。结果:海水浸泡后爆炸伤组的伤情明显重于脱器伤组,经救治后两组生存时间均明显延长,但锐器伤组更为明显。结论:本胸部爆炸伤模型是可行的并且重复性好,创伤后造成的呼吸循环功能变化与临床所见相符,适用于海水浸泡胸部开放伤的早期病理生理研究。爆炸伤的伤情更为严重,除严重电解质紊乱和高渗血症外,严重的肺损伤可能是影响生存时间的重要原因之一。 相似文献
19.
目的 研究卵巢浆、粘液性上皮瘤PCNA、p53、C-erbB-2基因产物的表达与细胞增殖关系。方法 采用S-P免疫组化法对110例卵巢浆、粘液性良恶性肿瘤进行PCNA、p53及C-erbB-2的检测。结果 在30例卵巢囊腺瘤、38例交界性囊腺瘤及42例腺癌中,PCNA的阳性表达分别为16.67%、0和0;p53的阳性表达分别为57.89%、39.47%和15.79%;C-erbB-2的阳性表达分别为90.48%、73.80%和42.86%。三组相比差异有显著性(P<0.05)。p53及C-erbB-2的表达在PCNA强阳性组大于PCNA的弱阳性组及阴性组,在浆液性肿瘤组大于粘液性肿瘤组。结论 卵巢交界性肿瘤在不同程度上具有与腺癌相似的癌基因表达,浆液性腺癌的预后比粘液性腺癌差,可能与癌基因表达阳性率有关。 相似文献
20.
讨论了基于主无分析(PCA)的过程故障检测与诊断的原理,运用T^2统计、Q统计方法,结合贡献图对一典型过程进行了仿真分析,结果表明PCA方法可对简单传感器故障进行检测与诊断,并指出了该方法中的不足,提出了将PCA方法同基于过程动态模型的故障诊断方法相结合的研究思路。 相似文献