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1.
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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Prions are infectious proteins believed to be responsible for a variety of progressive and fatal neurodegenerative diseases, collectively referred to as transmissible spongiform encephalopathies (TSE). By 1996, it was recognized that ingestion of beef from cattle afflicted with a TSE known as bovine spongiform encephalopathy, could result in a devastating human TSE known as variant Creutzfeldt-Jakob disease (vCJD). Two recent reports of probable transfusion-transmitted vCJD have raised concerns about the safety of the blood supply. The relatively long asymptomatic latency of vCJD, as well as the lack of sensitive and specific antemortem tests, increase the risk that asymptomatic, infected individuals may become blood donors. To this point, donor deferral has been a strategy used to reduce this risk. Nevertheless, this strategy may be unreliable and, furthermore, may threaten blood availability. Leukoreduction has also been helpful in reducing cell-associated infectious prion, which has been reported to reduce up to 42% of the infectivity in blood. Proprietary prion affinity surface modifications have been developed and applied to filters, which exploit an understanding of the unique chemical characteristics of prion surfaces. These have been successfully adapted to existing high-efficiency blood filter matrices for the reduction of prions present in blood components for transfusion.  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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Flow cytometry, singlet platelet counting, and optical aggregation have been used to monitor clopidogrel and glycoprotein IIb/IIIa (GPIIb/IIIa) platelet antagonists. Optical aggregation is considered the gold standard, but neither it nor flow cytometry is convenient in larger-scale clinical studies or point-of-care systems. Singlet platelet counting, a point-of-care assay correlated with optical platelet aggregation, only provides a measurement of platelet function at a single point in time. The Thrombelastograph is used to assay whole blood for thrombin-generated maximal clot-shear elasticity, referred to as the maximal amplitude (MA). Although platelet dysfunction, thrombocytopenia, and the in vitro effect of strong inhibitors such as IIb/IIIa antagonists can be observed, with thrombin generation milder platelet inhibitors cannot be assessed. We modified the Thromboelastograph assay, using reptilase and factor XIIIa, to form a clot, without thrombin generation, in heparinized whole blood. The resulting clot MA is dependent on added platelet agonists such as ADP or arachidonic acid, is sensitive to platelet antagonists, and provides a continuous measure of platelet function more analogous and better correlated with optical aggregation. This novel modification of the Thromboelastograph assay should prove to be a useful point-of-care whole-blood assay with which to monitor the effects of GPIIb/IIIa, ADP, and thromboxane A(2)-receptor-inhibiting drugs in patients.  相似文献   
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