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21.
MicroRNAs (miRNAs) are a family of small, noncoding RNA molecules that negatively regulate protein expression either by inhibiting initiation of the translation of mRNA or by inducing the degradation of mRNA molecules. Accumulating evidence suggests that miRNA‐mediated repression of protein expression is of paramount importance in a broad range of physiologic and pathologic conditions. In particular, miRNA‐induced dysregulation of molecular processes involved in inflammatory pathways has been shown to contribute to the development of chronic inflammatory diseases. In this review, first of all we provide an overview of miRNA biogenesis, the main mechanisms of action and the miRNA profiling tools currently available. Then, we summarize the available evidence supporting a specific role for miRNAs in the pathobiology of periodontitis. Based on a review of available data on the differential expression of miRNAs in gingival tissues in states of periodontal health and disease, we address specific roles for miRNAs in molecular and cellular pathways causally linked to periodontitis. Our review points to several lines of evidence suggesting the involvement of miRNAs in periodontal tissue homeostasis and pathology. Although the intricate regulatory networks affected by miRNA function are still incompletely mapped, further utilization of systems biology tools is expected to enhance our understanding of the pathobiology of periodontitis.  相似文献   
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An EU-wide cooperation on HTA has been proposed recently by the European Commission, focusing on relative effectiveness assessment (REA) for pharmaceuticals and medical devices. This cooperation is operationalised through a proposal for a regulation. While a good step in the right direction, this HTA cooperation framework needs to be more explicit and pragmatic about clinical value definition, what constitutes quality of evidence, how real-world evidence is handled, whether the same assessment requirements will apply for medical devices as they do for pharmaceuticals, and how to safeguard consistency in REA interpretation. If demand-rather than supply-driven, this initiative can deliver wider benefits: Europe can improve its power in global drug design and development, while Member States will have at their disposal more resources to assess performance of interventions in their healthcare systems.

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A 32-year-old man was admitted to the emergency department of our hospital after experiencing a peripheral arterial embolism. Investigation of the possible embolic sources in an otherwise asymptomatic patient revealed the existence of a left ventricular diverticulum. The left ventricular diverticulum is a rare congenital anomaly, either isolated or as a part of a syndrome including other congenital malformations. The treatment of choice, especially in symptomatic patients, is surgical resection, while in asymptomatic patients anticoagulation therapy is indicated.  相似文献   
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Clinical estimation of the combined effect of several risk factors is unreliable and this resulted in the development of a number of risk estimation systems to guide clinical practice. Here, after defining general principles of risk estimation, the authors describe the evolution of the European Society of Cardiology’s (ESC) Systematic COronary Risk Evaluation (SCORE) risk estimation system and some learnings from the data. They move on to describe the establishment of the ESC’s Cardiovascular Risk Collaboration and outline its proposed research directions. First among these is the evolution of SCORE 2, which provides updated, calibrated risk estimates for total cardiovascular events for low, moderate, high, and very high-risk regions of Europe. The authors conclude by considering that the future of risk estimation may be to express risk as years of exposure to a cardiovascular risk factor profile rather than risk over a fixed time period, such as 10 years, and how advances in genetics may permit individualized lifetime risk estimation from childhood on.  相似文献   
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Odontology - Recording fluorescence using flash photography, may help reduce time of capture and apply effectively in clinical practice. To test methods for visualizing composite resins...  相似文献   
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Fifteen patients with pure mitral stenosis (MS) underwent high-temporal-resolution radionuclide angiocardiography for calculation of the ratio of peak left ventricular (LV) filling rate divided by mean LV filling rate (filling ratio). Whereas LV filling normally occurs in 3 phases, in MS it is more uniform. Thus, in 13 patients the filling ratio was below the normal range of 2.21 to 2.88 (p < 0.001). In 11 patients in atrial fibrillation, filling ratio divided by mean cardiac cycle length and by LV ejection fraction provided good correlation (r = 0.85) with modified Gorlin formula derived mitral area and excellent correlation with echocardiographic mitral area (r = 0.95). Significant MS can be detected using radionuclide angiocardiography to calculate filling ratio. In the absence of the confounding influence of atrial systole calculation of 0.14 (filling ratio ÷ cardiac cycle length ÷ LV ejection fraction) +0.40 cm2 enables accurate prediction of mitral area (±4%). Our data support the contention that the modified Gorlin formula, based on steady-state hemodynamics, provides less certain estimates of mitral area for patients with MS and atrial fibrillation, in whom echocardiography and radionuclide angiocardiography may be more accurate.  相似文献   
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