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BACKGROUND: Intradermal botolinum toxin A (BTXA) is an advanced technique that emerged in response to the increased demand for noninvasive facial lifting and skin rejuvenation. OBJECTIVE: We sought to evaluate the safety and efficacy of intradermal injections of BTXA for facial lifting. METHODS: Twenty-five female patients with mild symmetrical facial skin laxity were enrolled in this study. All patients were treated with BTXA in one side of the face while the other side was injected with normal saline. The response to treatment was assessed by two dermatologists who evaluated global photographs using a quartile grading scale (QGS). The patient self-assessment and satisfaction questionnaires were recorded. RESULTS: A highly significant difference was found between the side injected with BTXA and the saline injected side (control) (p<0.001). Facial lifting was achieved in 58.66 percent of the sides injected with BTXA. Forty-four percent of patients were very satisfied. Older patients showed better improvement than younger patients (p=<0.001). The results persisted for 16 weeks. No adverse effects were observed. CONCLUSION: Our results suggest that intradermal injection of BTXA could be a safe and effective therapeutic option for face lifting.  相似文献   
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By going to millimeter wave (mmWave) we can use large scale MIMO due to short mmWave wavelength to overcome path loss by using beamforming to focus power of signal to the receiver. System structure of mmWave band is different with conventional MIMO because of large scale MIMO which is leading to use many RF-chains. For this reason Hybrid structure have been proposed for large Scale MIMO. By going to Hybrid structure a new issue has been created with phase shifter constraint. In this paper we propose a novel solution to make a hybrid precoding and combing to reach high spectral efficiency. Our problem includes a maximizing Frobenius norm of multiplying five complex matrices. As constraints, all elements of some matrices must have unit norm, and also the multiplication of some matrices must have a specific Frobenius norm. A novel solution is proposed for the problem, which is gained in two steps. At the first step, we propose a new decomposition usable for kind of complex matrices which could lead to reduce the dimension of the objective function, and eliminating constraints completely and in the second step, we propose an iterated algorithm for the resulting problem. By proposing another novel technique, we show that in each iteration, the optimal problem is equivalent to a quadratic optimal problem with limitations on the vector norm, and as a result, an optimal problem is obtained quickly. Moreover, some other real examples are included to demonstrate the usefulness and effectiveness of the proposed algorithm.  相似文献   
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A series of 2-(arylmethylthio)-3-phenylquinazolin-4-one derivatives have been synthesized and their antiplatelet aggregation activities were assessed against ADP and arachidonic acid-induced platelet aggregation in human plasma. Among the tested thioethers, derivative 2, 3, 5 and 16 were the most potent compounds with satisfactory IC50 for inhibition of platelet aggregation induced by ADP. Analysis of global physicochemical parameters shows some correlations between activities and molecular volume and also surface area of the studied derivatives.  相似文献   
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Ebrahim S 《Lancet》2002,360(9346):1692; author reply 1693-3; author reply 1693
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Abstract

Introduction: Tramadol is a synthetic opioid which is commonly used around the world to relieve moderate to severe pain. One of the serious possible complications of its use is seizures. The present study aims to investigate and summarize the studies related to tramadol and occurrences of seizures after tramadol use and factors influencing these seizures.

Methodology: Our systematic review is compliant with PRISMA guidelines. Two researchers systematically searched PubMed/Medline, Web of Sciences, and Scopus. Cohort, case-control, cross-sectional studies, and clinical trials. The risk of bias was assessed using the Newcastle–Ottawa Scale After article quality assessment, a fixed or random model, as appropriate, was used to pool the results in a meta-analysis. Heterogeneity between the studies was assessed with using I-square and Q-test. Forest plots demonstrating the point and pooled estimates were drawn.

Results: A total of 51 articles with total sample size of 101 770 patients were included. The results showed that seizure event rate in the subgroups of tramadol poisoning, therapeutic dosage of tramadol, and tramadol abusers was 38% (95% CI: 27–49%), 3% (95% CI: 2–3%), 37% (95% CI: 12–62%), respectively. Tramadol dose was significantly higher in the patients with seizures than those without (mean differences: 0.82, CI 95%: 0.17–1.46). The odds for occurrence of seizures were significantly associated with male gender (pooled OR: 2.24, CI 95%: 1.80–2.77). Naloxone administration was not associated to the occurrence of seizures (pooled OR: 0.47, 95% CI: 0.15–1.49).

Conclusions: Our results demonstrate that the occurrence of seizures in patients exposed to tramadol are dose-dependent and related to male gender, but not related to naloxone administration. Given that, most of the evidence derives from studies utilizing a cross-sectional design, the association of tramadol with seizures should not be considered to be definitively established  相似文献   
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