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This paper is concerned with the quantized synchronization control problem of coupled dynamic networks (CDNs) with communication constraints. The networked-induced delay, data packet dropouts, and signal quantization effects are simultaneously considered in the synchronization controller design. A new closed-loop coupled dynamic system is constructed, where both the interval time-varying delays and quantized parameters are taken into account. By using Kronecker product technique and the Lyapunov–Krasovskii functional approach, a stability criterion is obtained for the closed-loop CDNs, which also guarantees that the CDNs are synchronized. Then, both the networked controller and the quantized parameters can be designed. Finally, a simulation example is given to illustrate the effectiveness of the proposed method. 相似文献
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P Campolmi P Bonan G Cannarozzo N Bruscino M Troiano F Prignano T Lotti 《Journal of the European Academy of Dermatology and Venereology》2011,25(1):68-73
Background Intense pulsed light (IPL) treatment is one of the most effective procedures for patients with non‐aesthetic vascular lesions in addition to signs of skin photoageing, and it has been reported as very successful in the treatment of telangiectasias, spider nevi, erythrosis, and above all, rosacea and poikiloderma. Its use is based on the principle of selective photothermolysis, which exploits the haemoglobin absorption peak among its range of wavelengths. Objective The aim of this study is to assess the efficacy and safety of intense pulsed light in treating non‐aesthetic vascular skin lesions, especially with regard to poikiloderma of Civatte and rosacea. Methods A total of eighty‐five patients, 64 women and 21 men, with 63 non‐aesthetic vascular lesions (28 Poikiloderma of Civatte and 35 rosacea), 22 pigmented lesions (UV‐related hyperpigmentation of solar lentigo‐type) and four precancerous lesions (actinic keratosis, AKs), were treated repeatedly with IPL for 2 years. The patients received a mean of five treatments (range 4–6) at 3‐weekly intervals. They were evaluated via clinical observations and professional photographs were taken before each treatment and after 2 weeks, 4 weeks, 3 months, 6 months and 12 months. The outcome of the IPL treatments was evaluated by four independent dermatologists, who were not informed about the study protocol, and who assessed the performance of IPL by dividing the results into four categories: no results, slight improvement, moderate improvement and marked improvement. Results All the patients showed improvements in their overall lesions: 72 lesions (80.9%) achieved a marked improvement, 14 lesions (15.7%) achieved a moderate improvement and three lesions (3.4%) achieved a slight improvement. The results of the 63 non‐aesthetic vascular lesions in Rosacea and Poikiloderma of Civatte were: 51 with a marked improvement, 10 with moderate improvement, whereas only two lesions achieved a slight improvement. The improvement of all four actinic keratoses was marked whereas the 22 pigmented lesions obtained a marked improvement in 17 cases, a moderate improvement in four cases and a slight improvement in one case. No undesirable effects were observed. Conclusions Our study confirms how by minimizing side‐effects, time and costs, IPL can be effective and safe for the treatment of non‐aesthetic facial and neck vascular lesions. 相似文献
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Lund SS Tamow L Stehouwer CD 《药品评价》2008,5(8):380-380
在2型糖尿病患者中,反映炎症和内皮功能障碍的生物标志已经与心血管疾病和代谢调节联系起来。二甲双胍和促胰岛素分泌剂被证明有相同的抗高血糖作用。此研究比较了二甲双胍和促胰岛素分泌剂瑞格列奈在非肥胖的2型糖尿病患者的心血管疾病生物标志上的效能。 相似文献
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Eduardo Luiz Pedrazza Mario Roberto Senger Leonardo Pedrazza Fernanda Francine Zimmermann Jo?o José de Freitas Sarkis Carla Denise Bonan 《Toxicology in vitro》2007,21(4):671-676
The effects of sertraline, a selective serotonin reuptake inhibitor, and clomipramine, a tricyclic antidepressant, were tested on ecto-nucleotidases from synaptosomes of cerebral cortex and hippocampus of rats. Sertraline and clomipramine (100-500 microM) inhibited NTPDase, but not ecto-5'-nucleotidase activity in both cerebral cortex and hippocampus. In cortical synaptosomes, sertraline inhibited both ATP and ADP hydrolysis in the concentrations tested. The inhibitory effect varied from 21% to 83% for ATP hydrolysis and 48% to 75% for ADP hydrolysis. The inhibition promoted by sertraline in hippocampal synaptosomes varied from 38% to 89% for ATP hydrolysis and 45% to 77% for ADP hydrolysis. A significant inhibition of cortical NTPDase activity by clomipramine was observed in the all concentrations tested (35-72% and 36-87% for ATP and ADP hydrolysis, respectively). Similar effects were observed in hippocampus (29-91% and 48-83% for ATP and ADP hydrolysis, respectively). There was no inhibitory effect of sertraline and clomipramine on AMP hydrolysis in cerebral cortex and hippocampus. Our results have shown that classical antidepressants inhibit the extracellular catabolism of ATP. Therefore, it is possible to suggest that changes induced by antidepressants on bilayer membrane could affect NTPDase activities and consequently, modulating ATP and adenosine levels in the synaptic cleft. 相似文献
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Transmyocardial coil implants: a novel approach to transmyocardial revascularization 总被引:3,自引:0,他引:3
Meerkin D Pellerin M Aretz HT Paiement P Houser SL Bonan R 《The Annals of thoracic surgery》2002,74(2):488-492
BACKGROUND: Transmyocardial laser revascularization (TMLR) has potential benefit for patients with end-stage coronary artery disease and intractable angina not amenable to conventional revascularization techniques. Neovascularization has been proposed to occur around the laser channels. Our aim was to determine the feasibility of a novel nonlaser myocardial revascularization technique and its effect on angiogenesis in a nonischemic porcine model. METHODS: In the first phase, six transmyocardial stainless steel coil implants (TMI) were deployed to the lateral wall of the left ventricle in each of 6 pigs. The animals were sacrificed at 8 and 12 weeks, with a single animal dying prematurely at 4 weeks, and the myocardium was assessed for new vessel growth. In the second phase, 8 implants were deployed in each of 12 pigs with regular fluoroscopic follow-up until sacrifice at 2 weeks to assess implant stability. RESULTS: The deployment procedure was safe and feasible with no complications evident. A significant increase in new vessels at implant sites with 5.43 +/- 3.67, 4.97 +/- 2.44, and 3.57 +/- 2.29 seen per high power field at 12, 8, and 4 weeks, respectively, compared to 1.00 +/- 1.06 (p < 0.0001) in control myocardium. There was no evidence of implant migration in Phase 2. CONCLUSIONS: TMIs can feasibly be deployed in the nonischemic pig model with a high success rate. The presence of angiogenesis at the implant site and the maintenance of this reaction for 3 months implies that TMI may offer an alternative to TMLR while providing a platform for delivery of angiogenic factors. 相似文献
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