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The epithelial remnants of tooth development give rise to an impressive range of cystic lesions, termed odontogenic cysts. They are classified based on their distinct clinical, radiological and histological features, a process that has not been without controversy. We will attempt to explain the basis of the debate behind the changing classification of odontogenic cysts, describing their aetiology, clinical and histological features, along with common pitfalls that can confuse the diagnostic process. More common diagnostic challenges, such as the effects of inflammation and mucous change, will be explored in detail. An attempt will be made to distil the diagnostic process into simple algorithmic steps to narrow down the differential diagnoses of this fascinating group of lesions. We will demonstrate the importance of careful consideration of the clinical and radiological features that can help prevent misclassification, ensuring appropriate management and follow-up for this diverse group of lesions.  相似文献   
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Patients with active cancer are at an increased risk of arterial and venous thromboembolism (VTE) and bleeding events. Historically, in patients with cancer, low molecular weight heparins have been preferred for treatment of VTE, whereas warfarin has been the standard anticoagulant for stroke prevention in patients with atrial fibrillation (AF). More recently, direct oral anticoagulants (DOACs) have been demonstrated to reduce the risk of venous and arterial thromboembolism in large randomized clinical trials of patients with VTE and AF, respectively, thus providing an attractive oral dosing option that does not require routine laboratory monitoring. In this review, we summarize available clinical trial data and guideline recommendations, and outline a practical approach to anticoagulation management of VTE and AF in cancer.  相似文献   
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Synthetic amorphous silica (SAS) in its nanosized form is now used in food applications although the potential risks for human health have not been evaluated. In this study, genotoxicity and oxidative DNA damage of two pyrogenic (NM‐202 and 203) and two precipitated (NM‐200 and ‐201) nanosized SAS were investigated in vivo in rats following oral exposure. Male Sprague Dawley rats were exposed to 5, 10, or 20 mg/kg b.w./day for three days by gavage. DNA strand breaks and oxidative DNA damage were investigated in seven tissues (blood, bone marrow from femur, liver, spleen, kidney, duodenum, and colon) with the alkaline and the (Fpg)‐modified comet assays, respectively. Concomitantly, chromosomal damage was investigated in bone marrow and in colon with the micronucleus assay. Additionally, malondialdehyde (MDA), a lipid peroxidation marker, was measured in plasma. When required, a histopathological examination was also conducted. The results showed neither obvious DNA strand breaks nor oxidative damage with the comet assay, irrespective of the dose and the organ investigated. Similarly, no increases in chromosome damage in bone marrow or lipid peroxidation in plasma were detected. However, although the response was not dose‐dependent, a weak increase in the percentage of micronucleated cells was observed in the colon of rats treated with the two pyrogenic SAS at the lowest dose (5 mg/kg b.w./day). Additional data are required to confirm this result, considering in particular, the role of agglomeration/aggregation of SAS NMs in their uptake by intestinal cells. Environ. Mol. Mutagen. 56:218–227, 2015. © 2014 Wiley Periodicals, Inc.  相似文献   
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Background  Machine learning (ML) has captured the attention of many clinicians who may not have formal training in this area but are otherwise increasingly exposed to ML literature that may be relevant to their clinical specialties. ML papers that follow an outcomes-based research format can be assessed using clinical research appraisal frameworks such as PICO (Population, Intervention, Comparison, Outcome). However, the PICO frameworks strain when applied to ML papers that create new ML models, which are akin to diagnostic tests. There is a need for a new framework to help assess such papers. Objective  We propose a new framework to help clinicians systematically read and evaluate medical ML papers whose aim is to create a new ML model: ML-PICO (Machine Learning, Population, Identification, Crosscheck, Outcomes). We describe how the ML-PICO framework can be applied toward appraising literature describing ML models for health care. Conclusion  The relevance of ML to practitioners of clinical medicine is steadily increasing with a growing body of literature. Therefore, it is increasingly important for clinicians to be familiar with how to assess and best utilize these tools. In this paper we have described a practical framework on how to read ML papers that create a new ML model (or diagnostic test): ML-PICO. We hope that this can be used by clinicians to better evaluate the quality and utility of ML papers.  相似文献   
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目的探讨附着龈重建应用于口腔种植修复中的临床效果。方法将本院于2016年10月-2018年10月期间收治的行口腔种植修复治疗的附着龈缺失患者82例作为研究资料,依据治疗方案分组,对照组为传统修复治疗方案,观察组采用附着龈重建治疗修复方案,各41例,评价两组术后不同阶段附着龈宽度、龈缘外形及附着点重建改善效果,并评价患者评价治疗满意度。结果术后3个月观察组患者附着龈宽度改善Ⅲ级率56.10%明显高于对照组0.00%,龈缘外形与附着点重建Ⅲ级率60.98%明显高于对照组0.00%(P <0.05);术后6个月观察组患者附着龈宽度改善Ⅲ级率75.61%明显高于对照组0.00%,龈缘外形与附着点重建Ⅲ级率73.17%明显高于对照组0.00%(P <0.05);观察组治疗满意度97.56%与对照组70.73%比较明显更高(P <0.05)。结论针对行口腔种植修复治疗的附着龈缺失患者采用附着龈重建治疗修复方案利于快速恢复附着龈增加宽度,改善龈缘外形及附着点重建效果,获得患者的高度满意度,治疗价值较高。  相似文献   
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