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31.
32.
Chung-Ho Chen Chao-San Chang Chi-Hsin Hsieh Yu-Chuan Tseng Yee-Shyong Shen I-Yueh Huang Chia-Fu Yang Chun-Ming Chen 《Journal of oral and maxillofacial surgery》2006,64(8):1209-1213
PURPOSE: Various types of temporary implants have been introduced to serve as orthodontic anchorage. The hypothesis of this study is that microimplants of 1.2 mm diameter can be used as orthodontic anchors, and that their success is related to their length. The aim of this study is to determine the incidence of anchor retention after orthodontic force application for moving teeth, and to determine the relationship of microimplant length to retention rate. METHODS: Fifty-nine microimplants (diameter: 1.2 mm) were placed in 29 patients as orthodontic anchorages. After 2 weeks of microimplant placement, a force of 100 to 200 g was loaded with an elastometric chain or NiTi coil spring. Risk factors were characterized as to why a microimplant may fail, and Fisher's exact test was used for statistical analysis. RESULTS: Nine microimplants were removed and the overall success rate was 84.7%. Exploring the causes for failure, we found significant differences between the length of microimplants and success rate; 6 mm was 72.2% and 8 mm was 90.2%. CONCLUSIONS: The results suggest that microimplants are suited as an alternative orthodontic anchorage. We recommend that 8-mm microimplants are preferable to 6-mm. 相似文献
33.
Ke-Zhong Shen Steve W. Johnson 《皖南医学院学报》2003,22(Z1):30-31
Parkinson's disease is a neurodegenerative movement disorder that results from progressive loss of midbrain dopamine neurons, which consequently leads to hyperactivity of subthalamic neurons. 相似文献
34.
Liu-Guan Bian Qing-Fang Sun Wuttipong Tirakotai Wei-Guo Zhao Helmut Bertalanffy Jian-Kang Shen 《Skull base》2007,17(2):145-151
We report a patient with a posterior inferior cerebellar artery (PICA) aneurysm and an incidental facial nerve schwannoma at the cerebellopontine angle (CPA). A 46-year-old woman presented with the sudden onset of a severe headache, nausea, and vomiting. She had no other abnormal neurological symptoms and signs. Computed tomography (CT) showed hemorrhage in the fourth ventricle. Cerebral angiography demonstrated an aneurysm arising from the tonsillomedullary segment of the left PICA. A facial nerve schwannoma was incidentally found as the aneurysm was being clipped. The aneurysm was clipped via a left transcondylar approach. Subsequently, the schwannoma (2 x 3 x 2 mm) was resected from the facial nerve fascicles, and the facial nerve was preserved. Postoperatively, the patient developed mild to moderate dysfunction of the facial nerve (House-Brackmann grade III [H-B III]) but her hearing was intact. Both a facial nerve schwannoma involving the CPA and an aneurysm involving the PICA can be managed through the transcondylar approach. An asymptomatic facial nerve schwannoma can be resected safely with minimal facial nerve dysfunction. 相似文献
35.
Opioid tolerance and opioid-induced hyperalgesia are conditions that negatively affect pain management. Tolerance is defined as a state of adaptation in which exposure to a drug induces changes that result in a decrease of the drug's effects over time. Opioid-induced hyperalgesia occurs when prolonged administration of opioids results in a paradoxic increase in atypical pain that appears to be unrelated to the original nociceptive stimulus. Complex intracellular neural mechanisms, including opioid receptor desensitization and down-regulation, are believed to be major mechanisms underlying opioid tolerance. Pain facilitatory mechanisms in the central nervous system are known to contribute to opioid-induced hyperalgesia. Recent research indicates that there may be overlap in the two conditions. This article reviews known and hypothesized pathophysiologic mechanisms surrounding these phenomena and the clinical implications for pain management nurses. 相似文献
36.
沈心一 《中国动脉硬化杂志》2007,15(7):523-523
近30年来糖尿病患病率在多数欧美和亚洲国家中迅速增高。糖尿病心血管并发症是糖尿病患者的主要死亡原因,其发生机制不甚明了。糖尿病有关的代谢因素增加循环和组织中氧化和糖化蛋白或脂蛋白的水平和氧化应激性。这些改变可引起动脉粥样硬化,凝血因子和血小板活性增高,纤溶活性 相似文献
37.
肠道T细胞淋巴瘤临床分析 总被引:1,自引:0,他引:1
本文总结报告了3例肠道T细胞淋巴瘤(intestinal T-cell lymphoma,ITCL)的诊治资料,并结合文献复习,发现IT—CL多见于中年男性,以腹痛、血便、发热、体质量下降为主要症状,治疗效果差,预后不良。病理改变以肠道溃疡形成为特点,溃疡形态呈多形性、多灶性、不规则,镜下瘤细胞明显异型、弥漫性浸润,中至大细胞多见。肿瘤细胞呈T细胞表型。ITCL临床少见,缺乏特异性临床表现,极易误诊。故临床医师应重视对ITCL临床病理特征、免疫表型和基因型的研究,注意识别,促其早期诊治。 相似文献
38.
浅谈健康教育中的护理风险管理 总被引:3,自引:0,他引:3
健康教育作为临床护理中的重要内容,对病人的疾病转归有重要作用。而任何医疗护理行为都是具有超过各种服务之上的高科技行为的组合活动,具有高风险性,健康教育同样存在一定的风险性。所以,我们应提高风险意识,加强风险管理,将风险降低至最低限度。 相似文献
39.
根据桂枝汤的效应消除半衰期和表观消除半衰期制订给药方案的探讨 总被引:3,自引:0,他引:3
为探讨药效法估测的效应消除半衰期和效量法估测的表观半衰期对合理制订给药方案的意义和作用,以桂枝汤解热和抗炎的药物动力学实验中所得的相应参数值设计了给药方案,观察了它们在提高药效上的作用。结果表明在给药总剂量相等、首次给药同时开始的情况下,以半衰期设计的给药方案组的药效均明显高于习惯的一次给药组;而以效应消除半衰期设计给药方案组药效增强率又高于以表观半衰期设计的方案组。提示效应消除半衰期比表观半衰期似更有实践意义。 相似文献
40.
Y E Shen W G Sorenson D M Lewis S A Olenchock 《Biomedical and environmental sciences : BES》1990,3(3):353-363
Fourteen samples of settled dust from two factories processing rice and wheat straw near Shanghai, China, were examined by dilution plating for total bacteria, gram-negative bacteria, thermophilic actinomycetes, and fungi. They were also examined for aflatoxin, endotoxin, and potential to stimulate production of human interleukin 1 beta (IL-1 beta) and to consume complement. The concentrations of total microorganisms were consistently greater than 10(7) CFU/g and ranged from 10(7) to 10(9) CFU/g. In general, the level of microbial contamination was greater in the hay dust samples than in the rice dust samples, with bacteria being the most numerous microorganisms observed followed by molds, thermophilic actinomycetes, and yeasts. The predominant fungi were species of Aspergillus, Cladosporium, Penicillium, Trichosporon, and Cryptococcus. No significant levels of aflatoxin were observed and the isolates of A. flavus examined lack significant aflatoxigenic potential. The levels of microorganisms in these samples, the types of organisms found, and the inflammatory mediators such as endotoxin suggest that workers exposed to these dusts may be at risk for respiratory illness. 相似文献