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81.
Skin necrosis is the most severe complication arising from hyaluronic acid (HA) injection. To avoid skin necrosis, hyaluronidase should be injected along the course of the involved artery, to allow blood flow restoration. We evaluated the ability of hyaluronidase to degrade a HA filler in two simulated clinical situations—a compression case and an embolization case—to identify differences in the hyaluronidase injection. In the compression case, a bolus of HA filler was directly soaked in hyaluronidase solution; in the embolization case, a vein harvested from a living patient was filled with the same HA filler and then soaked in hyaluronidase. We then evaluated the quantity of HA remaining after 2 hr. While we found hydrolysis of HA in both cases, in the compression case, we detected almost complete hydrolysis, whereas in the embolization case we observed a reduction of the 60%. Our results support the hypothesis that vessel compression can be resolved with only one injection of hyaluronidase, while in the case of vascular embolization, repeated perivascular injections should be performed owing to the reduction of hyaluronidase activity.  相似文献   
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Background: The systemic use of combined amoxicillin and metronidazole (AMX/MET) as an adjunctive treatment to full‐mouth scaling and root planing (FMSRP) has been proposed for the treatment of generalized aggressive periodontitis; however, its effectiveness and clinical safety remain to be defined. The purpose of the present meta‐analysis is to assess the effectiveness of FMSRP + AMX/MET compared to FMSRP alone. Methods: An electronic search of eight databases and a hand‐search of 10 international dental journals were conducted through September 11, 2011. Gain in clinical attachment level (CAL), reduction in probing depth (PD), secondary outcomes, and adverse events were analyzed. A random‐effect model was used to pool the extracted data. The weighted mean difference (MD) with 95% confidence interval (CI) was calculated for continuous outcomes, whereas risk difference (RD) with 95% CI was used for dichotomous data; heterogeneity was assessed with the χ2‐based Cochran Q test and I2 statistic. The level of significance was set at P <0.05. Results: After the selection process, six randomized clinical trials were included. Results of the meta‐analysis showed significant CAL gain (MD, 0.42; 95% CI, 0.23 to 0.61; P <0.05) and PD reduction (MD, 0.58; 95% CI, 0.39 to 0.77; P <0.05) in favor of FMSRP + AMX/MET; moreover, no significant RD was found in the occurrence of adverse events (RD, 0.01; 95% CI, ?0.02 to 0.04; P >0.05). Conclusion: The findings of the meta‐analysis seem to support the effectiveness and the clinical safety of FMSRP + AMX/MET; however, future studies are needed to confirm these results.  相似文献   
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Osteomas are the most common benign tumors of the paranasal sinuses. They are usually localized in the frontal sinus and less often in the other paranasal sinuses. In this article, we report the surgical treatment of an unknown frontal sinus osteoma discovered after an acute exophthalmos. We have chosen an external approach to obtain a radical excision of the tumor, but we prefer a direct frontal incision following a horizontal wrinkle to the classic bicoronal flap to avoid an unsightly scar because of patient's hair loss. We discuss the surgical approach, the reconstruction of the roof of the orbit involved, and patient's satisfaction.  相似文献   
84.
Pseudoexfoliation (PEX) syndrome is a common ocular disease that also affects the cornea. A case of clinical PEX syndrome, studied by in vivo corneal confocal microscopy is reported. The morphological analysis of the confocal images demonstrated hyper-reflective deposits and several dendritic cells in the basal epithelial layer. A fibrillar subepithelial structure was also found. The endothelial layer showed cell anomalies (polymegathism and pleomorphism) and hyper-reflective small endothelial deposits. Confocal microscopy is an in vivo imaging method that may provide new information on corneal alterations in PEX, and detect early corneal features.  相似文献   
85.
Respiratory complications are common in the patient with muscular dystrophy. The periodic clinical and instrumental respiratory evaluation is extremely important. Despite the presence in the literature of updated guidelines, patient associations often report lack of knowledge of these pathologies, particularly in peripheral hospitals. The purpose of this work, inspired by the Italian Muscular Dystrophy Association (UILDM) is to improve management of respiratory problems necessary for the management of these patients complex. To this end, the main items that the specialist can meet in the follow-up of these pathologies have been analyzed and discussed, among which the respiratory basal evaluation, the criteria of adaptation to non-invasive ventilation, management of bronchial secretions, situations of respiratory emergency, indications for tracheostomy and the subject of advance directives of treatment (DAT).Key words: respiratory failure, muscular dystrophy, cough efficacy, spirometry, polygraphy, non-invasive ventilation, arterial blood gases, cough machine, invasive ventilation, tracheostomy, mechanical ventilation  相似文献   
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Neuronal nicotinic acetylcholine (AcCho) receptors composed of alpha7-subunits (alpha7-AcChoRs) are involved in many physiological activities. Nevertheless, very little is known about their single-channel characteristics. By using outside-out patch-clamp recordings from Xenopus oocytes expressing wild-type (wt) alpha7-AcChoRs, we identified two classes of channel conductance: a low conductance (gamma(L)) of 72 pS and a high one (gamma(H)) of 87 pS, with mean open-times (tau(op)) of 0.6 ms. The same classes of conductances, but longer tau(op) (3 ms), were seen in experiments with chimeric alpha7 receptors in which the wtalpha7 extracellular C terminus was fused to the green fluorescent protein (wtalpha7-GFP AcChoRs). In contrast, channels with three different conductances were gated by AcCho in oocytes expressing alpha7 receptors carrying a Leu-to-Thr 248 mutation (mutalpha7) or oocytes expressing chimeric mutalpha7-GFP receptors. These conductance levels were significantly smaller, and their mean open-times were larger, than those of wtalpha7-AcChoRs. Interestingly, in the absence of AcCho, these oocytes showed single-channel openings of the same conductances, but shorter tau(op), than those activated by AcCho. Accordingly, human homomeric wtalpha7 receptors open channels of high conductance and brief lifetime, and fusion to GFP lengthens their lifetime. In contrast, mutalpha7 receptors open channels of lower conductance and longer lifetime than those gated by wtalpha7-AcChoRs, and these parameters are not greatly altered by fusing the mutalpha7 to GFP. All this evidence shows that GFP-tagging can alter importantly receptor kinetics, a fact that has to be taken into account whenever tagged proteins are used to study their function.  相似文献   
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