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High-resolution ultrasound is preferred as the first-line imaging modality for evaluation of superficial soft tissues, such as the facial muscles. In contrast to magnetic resonance imaging and computed tomography, which require specifically designated planes (axial, coronal and sagittal) for imaging, the ultrasound transducer can be navigated based on the alignment of facial muscles. Botulinum toxin injections are widely used in facial cosmetic procedures in recent times. Ultrasonography is recognized as a useful tool for pre-procedure localization of target muscles. In this pictorial review, we discuss the detailed sonoanatomy of facial muscles and their clinical relevance, particularly with regard to botulinum toxin injections. Furthermore, we have summarized the findings of clinical studies that report ultrasonographic imaging of facial muscles.  相似文献   
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AIMS: This study was undertaken to compare periodontal conditions, gingival crevicular fluid (GCF) levels of tissue-type plasminogen activator (t-PA), its inhibitor plasminogen activator inhibitor-2 (PAI-2), interleukin-1beta (IL-1beta), prostaglandin E(2) (PGE(2)) in rheumatoid arthritis (RA) patients and control groups. METHODS: Twenty-three RA patients, 17 systemically healthy patients with periodontal disease (PD), and 17 systemically and periodontally healthy subjects were recruited. GCF samples were obtained from two single-rooted teeth. Full-mouth clinical periodontal measurements were recorded at six sites/tooth. GCF samples were analysed using relevant ELISA kits. Data were tested statistically by appropriate tests. RESULTS: Total amounts of t-PA, PAI-2 and PGE(2) in GCF samples of the healthy control group were significantly lower than the other groups (p<0.05). The RA group exhibited a higher total amount of t-PA in GCF samples than the PD group (p<0.05). PAI-2, IL-1beta and PGE(2) total amounts were similar in RA and PD groups (p>0.05). CONCLUSION: The coexistence of RA and periodontitis does not seem to affect clinical periodontal findings or systemic markers of RA. Similar inflammatory mediator levels in RA and PD groups, despite the long-term usage of corticosteroids, non-steroidal anti-inflammatory drugs, suggest that RA patients may have a propensity to overproduce these inflammatory mediators.  相似文献   
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Late potentials (LP) detected on the signal-averaged electrocardiogram (SAECG) predict arrhythmic events after acute myocardial infarction (AMI). It is also well established that successful thrombolytic therapy reduces the incidence of LP. Our aim was to evaluate the effects of a beta-blocker on LP in patients receiving thrombolytic therapy. We studied 40 patients presenting with anteroseptal AMI (< 6 hours). All patients received thrombolytic therapy and were evaluated with coronary angiography at predischarge. Eighteen patients received metoprolol (5 mg IV on admission followed by 50 mg BID). SAECG recordings were obtained serially using an ART system (40-250 Hz filter, noise < 0.5 mV) prior to thrombolytic therapy, after 48 hours and after 10 days. LP was defined as posi-tive if the SAECG met at least 2 of the Gomes criteria. Changes observed in SAECG recordings after thrombolytic therapy were correlated with angiographic and clinical data with regard to the usage of BB. The frequencies of LP before and after thrombolytic therapy were compared with the McNemar test. There were no significant differences between the clinical characteristics, risk factors, and angiographic findings (including infarct related artery patency and LV functions) of the groups. Baseline SAECG findings were also similar between the groups. The incidence of LP significantly decreased after TT in the BB group, however, this change was not observed in patients who did not receive BB (P = 0.012, McNemar test). Beta-blockers reduce the incidence of LPs following thrombolytic therapy in patients with anterior AMI. This might be explained by the possible beneficial effect of BB on the arrhythmogenic substrate.  相似文献   
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