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In this paper, we present a novel decentralized robust methodology for control of quiet upright posture during arm-free paraplegic standing using functional electrical stimulation (FES). Each muscle–joint complex is considered as a subsystem and individual controllers are designed for each one. Each controller operates solely on its associated subsystem, with no exchange of information between them, and the interaction between the subsystems are taken as external disturbances. In order to achieve robustness with respect to external disturbances, unmodeled dynamics, model uncertainty and time-varying properties of muscle–joint dynamics, a robust control framework is proposed. The method is based on the synergistic combination of an adaptive nonlinear compensator with sliding mode control (SMC). Fuzzy logic system is used to represent unknown system dynamics for implementing SMC and an adaptive updating law is designed for online estimating the system parameters such that the global stability and asymptotic convergence to zero of tracking errors is guaranteed. The proposed controller requires no prior knowledge about the dynamics of system to be controlled and no offline learning phase. The results of experiments on three paraplegic subjects show that the proposed control strategy is able to maintain the vertical standing posture using only FES control of ankle dorsiflexion and plantarflexion without using upper limbs for support and to compensate the effect of external disturbances and muscle fatigue. 相似文献
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Hamid-Reza Adhami Johannes Lutz Hanspeter K?hlig Martin Zehl Liselotte Krenn 《Scientia pharmaceutica》2013,81(3):793-805
The use of herbal medicinal preparations in dementia therapy has been studied based on experience from traditional medicine. A dichloromethane extract of gum ammoniacum, the gum-resin from Dorema ammoniacum D. Don had shown acetylcholinesterase (AChE) inhibitory activity in a previous study. The aim of this study was the isolation and characterization of the active compounds from this resin. The extract was investigated by a respective colorimetric microplate assay and the active zones were identified via TLC bioautography and isolated using several chromatographic techniques. The structures of the active components were characterized by one- and two-dimensional 1H and 13C NMR spectroscopy and mass spectrometry as (2′S,5′S)-2′-ethenyl-5′-(3-hy-droxy-6-methyl-4-oxohept-5-en-2-yl)-7-methoxy-2′-methyl-4H-spiro[chromene-3,1′-cyclopentane]-2,4-dione (1), which is an analogue of doremone A and a new natural compound, and as (2′S,5′R)-2′-ethenyl-5′-[(2R,4R)-4-hydroxy-6-methyl-3-oxohept-5-en-2-yl]-7-methoxy-2′-methyl-4H-spiro[chromene-3,1′-cyclo-pentane]-2,4-dione (2 = doremone A), (4E,8E)-1-(2,4-dihydroxyphenyl)-5,9,13-trimethyltetradeca-4,8,12-trien-1-one (3 = dshamirone), and 4,7-dihydroxy-3-[(2E,6E)-3,7,11-trimethyldodeca-2,6,10-trien-1-yl]-2H-chromen-2-one (4 = am-moresinol). Dshamirone turned out to be the most active compound with an IC50 value for AChE inhibitory activity of 23.5 μM, whereas the other substances showed weak activity. The concentrations of the analytes in the resin were determined by HPLC as 3.1%, 4.6%, 1.9%, and 9.9%, respectively. 相似文献
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Maryam Babaei Ruhollah Ghahramani-Asl Hamid-Reza Sadoughi Dariush Sardari Sohrab Shahzadi 《Australasian physical & engineering sciences in medicine / supported by the Australasian College of Physical Scientists in Medicine and the Australasian Association of Physical Sciences in Medicine》2018,41(3):697-711
Over 90% of craniopharyngeal brain tumors are cystic, which enables the injection of beta emitters such as phosphorus-32 (32P) radio-colloid into cysts for their treatment. The aim of this study was to evaluate the clinical and theoretical modelling of Bremsstrahlung radiation dose resulting from stereotactic radio-colloid therapy of cystic craniopharyngioma tumors with 32P. 32P radio-colloid with appropriate activity concentration was injected to a head phantom, and then the Bremsstrahlung radiation spectrum and planar images were obtained using a gamma camera. Both phantom and gamma camera were simulated using MCNPX code, and the results were compared with practical results. Bremsstrahlung radiation spectrum was measured using a handheld gamma spectrometer for two patients treated with stereotactic radio-colloid therapy with 32P in different positions and compared to Monte Carlo simulation. Results of counting and determining sensitivity coefficients in the air and the attenuating environment were obtained. Also, comparing the counting sensitivity from practical and simulation methods indicated the agreement of the data between the two methods. Comparison of the spectra from different positions around patient’s head indicated the ability to use this detector to quantify the activity in the operating room. Selection of the spectrum is important in Bremsstrahlung radiation imaging. We can take advantage of spectrometry measurement using gamma camera, handheld gamma spectrometer for patient, and theoretical modeling with Monte Carlo code to evaluate radiopharmaceutical distribution, leakage, as well as estimate activity and predict therapeutic effects in other adjacent structures and ultimately optimize radio-colloid therapy in cystic craniopharyngeal patients. 相似文献
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Afshar R Sanavi S Taheri HR 《Saudi journal of kidney diseases and transplantation》2012,23(1):117-121
Multiple endocrine neoplasia (MEN) is a group of heritable syndromes characterized by aberrant growth of benign or malignant tumors in a subset of endocrine tissues. There are three major syndromes: MEN1, 2A and 2B. We describe a 60-year-old woman who initially manifested acute renal failure due to hypercalcemia and dehydration and, finally, was diagnosed as a sporadic MEN1 case. 相似文献
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Malakoplakia of colon in a child with celiac disease and chronic granulomatous disease. 总被引:1,自引:0,他引:1
Hamidreza Kianifar Nourie Sharifi Saeed Talebi Mohammad Ali Kiani 《Indian journal of gastroenterology》2006,25(3):163-164
Malakoplakia is a rare pseudotumoral inflammatory disease known to affect immunocompromised subjects. We report a 4-year-old boy with malakoplakia of colon who was diagnosed with celiac disease in late infancy; despite aggressive nutritional and medical management for celiac disease, symptoms did not resolve. His nitro-blue-tetrazolium test was compatible with chronic granulomatous disease. In colonic biopsy Michaelis-Gutmann bodies were seen. 相似文献
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Farkhondeh?SharifEmail author Sadrollah?Mohebbi Hamid-Reza?Tabatabaee Mehdi?Saberi-Firoozi Sakineh?Gholamzadeh 《Health and quality of life outcomes》2005,3(1):81
Background
Chronic liver diseases (CLDs) are progressive disorder which has a significant impact on the well-being of patients and leads to significant morbidity. CLDs are characterized by disturbances in physical, psychological and social aspects of well-being. It causes significant health-related quality of life (QOL) impairment. Psycho-educational interventions targeting to functional factors could be beneficial for patients with CLDs. 相似文献9.
Fazli-Tabaei S Yahyavi SH Alagheband P Samie HR Safari S Rastegar F Zarrindast MR 《Behavioural pharmacology》2005,16(8):613-619
The present study investigated cross-tolerance between antinociception induced by water swim-stress and morphine in the formalin test. Intraperitoneal administration of morphine (3, 6 and 9 mg/kg) induced dose-dependent antinociception in both phases of the formalin test. Mice treated with a lower dose of morphine (25 mg/kg), once daily for 3 days, showed tolerance to antinociception induced by a lower test dose of morphine (3 mg/kg). Similar repeated treatments with a higher dose of morphine (50 mg/kg) produced tolerance to antinociception induced by different test doses of morphine (3, 6 and 9 mg/kg). Exposure to water swim-stress, once daily for 2 or 3 days in order to induce tolerance, also decreased morphine-induced antinociception. Swim-stress exposure for 2 or 3 days also tends to potentiate tolerance induced by a lower dose of morphine. Acute swim-stress of different durations (0.5, 1 and 3 min) induced antinociception in both phases of the formalin test, which was not reduced by naloxone, but showed even more antinociception in the second phase. The response to swim stress was decreased in mice treated with higher doses of morphine, but not those animals that received swimming stress (3 min) once daily for 2-3 days, in order to induce habituation to swim-stress-induced antinociception. The results may indicate a possible cross-tolerance between antinociception induced by morphine and by swim stress. 相似文献
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Saberi H Moshayedi P Aghayan HR Arjmand B Hosseini SK Emami-Razavi SH Rahimi-Movaghar V Raza M Firouzi M 《Neuroscience letters》2008,443(1):46-50
Several experimental studies have introduced Schwann cell transplantation as a means of recovery in animal models of spinal cord injury (SCI). The reported promising results together with the availability of autologous sources for Schwann cells indicate Schwann cell transplantation as a possible treatment for SCI. To address the safety and feasibility concerns we report 1-year follow-up of four patients aged between 22 and 43 years who had stable chronic (28-80 months) spinal cord injury at mid-thoracic level and treated with autologous Schwann cell transplantation. Purified Schwann cells used for transplantation were acquired from autologous sural nerve and cultured without the use of any specific mitogenic or growth factors. The patients were evaluated by means of American Spinal Injury Association (ASIA) criteria, sphincter, sexual function and Magnetic Resonance Imaging assessments for 1 year after transplantation. None of the patients were found to have any adverse effects indicating transfer of infection, neurological deterioration or other related clinical problems. Of the four patients, only one patient with incomplete SCI showed motor and sensory improvement 1 year after transplantation with extensive and continuous rehabilitation. All the four patients experienced transient paresthesia or increased muscle spasm after transplantation. Magnetic Resonance (MR) images of the patients did not show any visible changes or pathological findings after 1 year. This preliminary report shows that autologous Schwann cell transplantation is generally safe for the selected number of SCI patients but it does not prove beneficial effects. Further safety and outcome studies are recommended. 相似文献