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Electrocautery can induce significant alterations in the connective tissues and epithelium of specimens removed for diagnostic or therapeutic purposes. When electrocautery is used during parotid surgery, it can cause an oncocytoid artifact. The alterations described in this article are enlarged, tightly packed serous acinar cells with coarse to granular eosinophilic cytoplasm, distinct cell borders, and round basal nuclei that on cursory microscopic examination resemble oncocytes with respect to morphology. These changes are seen in conjunction with other, more recognized changes secondary to electrocautery and are believed to occur as a consequence of the electrothermal discharge. On the basis of our findings, this artifact is common in parotid surgical specimens and was misdiagnosed as benign oncocytic lesions in 5 cases.  相似文献   
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Proper management of periodontal tissues is required to achieve predictable long-term success with restorative dental procedures. Forced eruption as well as several surgical techniques may be used to achieve and maintain adequate biologic width during restorative and esthetic dental procedures. The technique that will yield optimal results depends on the relationship between the restoration's margins and the surrounding periodontium. A classification system that describes these interrelationships and provides treatment recommendations is included.  相似文献   
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Rotavirus A (RVA) is the leading cause of acute viral gastroenteritis in children under 5 years of age worldwide. G9P[8] is a common RVA genotype that has been persistently prevalent in Jiangsu, China. To determine the genetic diversity of G9P[8] RVAs, 7 representative G9P[8] strains collected from Suzhou Children’s Hospital between 2010 and 2016 (named JS2010‐JS2016) were analyzed through whole‐genome sequencing. All evaluated strains showed the Wa‐like constellation G9‐P[8]‐I1‐R1‐C1‐M1‐A1‐N1‐T1‐E1‐H1. Furthermore, phylogenetic analysis revealed that the VP7 genes of all strains clustered into lineage G9‐III and G9‐VI. With the exception of strain JS2012 (P[8]‐4), the VP4 sequences of all strains belonged to the P[8]‐3 lineage. Sequencing further revealed that amino acid substitutions were present in the antigenic regions of the VP7 and VP4 genes of all strains. Moreover, there were multiple substitutions in antigenic sites I and II of the nonstructural protein 4 (NSP4) genes, whereas the other NSP genes were relatively conserved. In conclusion, our phylogenetic analysis of these 7 G9P[8] strains suggests that RVA varied across regions and time. Therefore, our findings suggest that continued surveillance is necessary to explore the molecular evolutionary characteristics of RVA for better prevention and treatment of acute viral gastroenteritis.  相似文献   
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Timely diagnosis of osseous tumors is essential in providing proper management. Appropriate imaging studies are essential to this process, however, if inconclusive, they can be superceded by information obtained through the patient history and physical examination. Disclaimer: Dr. Bhandari's salary was provided, in part, by a scholarship from the R.K Frasier Research Foundation  相似文献   
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In the past 3 years there have been five further cases, in additionto one case reported in 1985, of Creutzfeldt-Jakob disease inrecipients of human growth hormone in the United Kingdom. Theclinical findings of two of these cases are described, demonstratinga typical presentation with a predominantly cerebellar syndromeat onset which is not commonly a presenting feature of sporadicCreutzfeldt-Jakob disease. In one case a 99mTc hexamethylpropylenaminesingle photon emission tomographic scan showed marked impairmentof tracer uptake in the basal ganglia and cerebral cortex ata time when the clinical picture was predominantly cerebellar.This technique may be useful in early diagnosis. In the othercase post mortem examination of the brain showed prominent amyloiddeposition in the cerebellum, which has not been described previouslyin pituitary-hormone related Creutzfeldt-Jakob disease. Thepreviously published cases of growth hormone-related Creutzfeldt-Jakobdisease are reviewed and reasons for the particular clinicalpattern seen are discussed.  相似文献   
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番茄红素与成骨细胞、破骨细胞及骨质疏松症   总被引:1,自引:0,他引:1  
学术背景:骨质疏松症是较易发生的疾病,研究骨质疏松的发病机制寻找治疗骨质疏松的药物是预防老年性骨质疏松症的理想选择。目的:综述近几年来国内外关于氧化应激及番茄红素在骨质疏松发病中的作用的相关研究,为开发预防和治疗骨质骨质疏松的药物提供理论依据。检索策略:应用计算机检索Medline和Science Direct Online数据库1989-01/2007-04期间的相关文章,检索词为"oxidative stress,osteoclast,osteoblast,lycopene,osteoporosis",限定文章语言种类为English。同时计算机检索中国期刊全文数据库2000-01/2007-04期间的相关文章,检索词为"氧化应激,骨质疏松,成骨细胞,破骨细胞,番茄红素",限定文章语言种类为中文。对资料进行初审,选择有关人体内氧化应激形成机制、氧化应激与成骨细胞、氧化应激与破骨细胞、氧化应激与抗氧化剂、番茄红素与成骨细胞及破骨细胞和番茄红素与骨质疏松症关系的最新进展文献,共收集到121篇,排除综述类及重复研究。文献评价:符合纳入标准的31篇文献中,5篇涉及骨质疏松症的概述,20篇涉及氧化应激和抗氧化剂在骨质疏松症发病中作用的相关研究,6篇涉及番茄红素与氧化应激、成骨细胞、破骨细胞及绝经后骨质疏松关系的相关研究。资料综合:氧化应激是骨质疏松发病的一个危险因素。氧化应激不但作用于成骨细胞还作用于破骨细胞。国内外学者对于番茄红素的抗氧化性能研究取得了很大进展,已通过细胞培养观察到其对成骨细胞和破骨细胞均有作用,通过临床研究发现,番茄红素通过其抗氧化功能而影响成骨细胞和破骨细胞的功能,从而能够对骨质疏松症发生发展的病理过程进行有效干预,最终阻止和减缓骨质疏松症的发生。结论:番茄红素具有的抗氧化功能使其在骨质疏松的预防及治疗方面起着重要的作用。  相似文献   
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