996 resultados para Indirect pulp therapy
Resumo:
The clinical trials of tumor therapy using heavy ions beam C-12 are now in progress at Institute of Modem Physics in Lanzhou. In order to achieve the precise radiotherapy with the high energy C-12 beam in active pencil beam scanning mode, we have developed an ionization chamber(IC) as an online monitor for beam intensity and also a dosimeter after calibration. Through the choosing of working gas and voltage, optimizing of the electrics and the read-out system, calibrating the linearity, the detector system provide us one of the simple and highly reliable way to monitoring the beam during the active pencil beam scanning treatments. The measurement results of this detector system show that it could work well under the condition of high energy C-12 beam in active pencil beam scanning mode.
Resumo:
癌症是现代医学的难题,一直危害着人类的健康。放射治疗是癌症治疗的有效手段之一。由于重离子束在物理学和生物学性质上所具有的优势,它已成为放疗用的最佳射线。简述了重离子治癌的发展历程、现状以及特点,详细讨论了在医学物理和放射生物学研究领域值得关注的若干热点问题。
Resumo:
介绍了中国科学院近代物理研究所重离子治癌装置的安装定位测量技术和方法。利用激光跟踪仪通过控制网的建立,和多重坐标系的转换,使最后的磁铁安装径向相对误差不超过±(0.05-0.1)mm,真空管道的横向及竖向精度也达到了±(0.1-0.2)mm。
Resumo:
For radiation protection purposes, the neutron dose in carbon ion radiation therapy at the HIRFL (Heavy Ion Research Facility in Lanzhou) was investigated. The neutron dose from primary C-12 ions with a specific energy of 100 MeV/u delivered from SSC was roughly measured with a standard Anderson-Broun rem-meter using a polyethylene target at various distances. The result shows that a maximum neutron dose contribution of 19 mSv in a typically surface tumor treatment was obtained, which is less than 1% of the planed heavy ion dose and is in reasonable agreement with other reports. Also the gamma-ray dose was measured in this experiment using a thermo luminescent detector.
Resumo:
The development of a method for determining arsenic species by capillary zone electrophoresis (CZE) with indirect laser-induced fluorescence (LIF) is described in this paper. The buffer pH, the concentration of fluorescein, the nature and the concentration of the background electrolytes (BGEs) were defined. When 2.0 mM NaHCO3 (pH 9.28) with 10(-7) M fluorescein was used as the buffer, arsenite (As(lll), dimethylarsonic acid (DMA), monomethylarsonic acid (MMA), and arsenate (As(V)) were all separated from one another. The limits of detection for the four arsenic species were p p in the range of 0.12-0.54 mg/L. This method was used in the analysis of spiked arsenic species in tap and mineral water to demonstrate its usefulness. The results showed that both the recovery and the reproducibility of the developed method were acceptable.
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A novel tris(2,2'-bipyridine)ruthenium(II) (Ru(bpy)3(2+)) cathodic electrochemiluminescence (ECL) was generated at -0.78V at the Pt electrode in acetonitrile (ACN), which suggested that the cathodic ECL differed from conventional cathodic ECL It was found that tripropylamine (TPrA) could enhance this cathodic ECL and the linear range (log-log plot) was 0.2 mu M-0.2 mM. In addition, hydrogen peroxide (H2O2) could inhibit the cathodic ECL and was indirectly detected with the linear range of 27-540 mu M. The RSD (n = 12) of the ECL intensity in the presence of 135 mu M H2O2 was 0.87%. This method was also demonstrated for the fast determination of H2O2 in disinfectant sample and satisfactory results were obtained.
Resumo:
Tangential flow affinity membrane cartridge (TFAMC) fs a new model of immunoadsorption therapy for hemoperfusion. Recombinant Protein A was immobilized on the membrane cartridge through Schiff base formation for extracorporeal IgG and immune complex removal from blood. Flow characteristics, immunoadsorption capacity and biocompatibility of protein A TFAMC were studied. The results showed that the pressure drop increased with the increasing flow rate of water, plasma and blood, demonstrating reliable strength of membrane at high now rare. The adsorption capacities of protein A TFAMC for IgG from human plasma and blood were measured. The cartridge with 139 mg protein A immobilized on the matrix (6 mg protein A/g dry matrix) adsorbed 553 mg IgG (23.8 mg IgG/g dry matrix) from human plasma and 499.4 mg IgG (21.5 mg IgG/g dry matrix) from human blood, respectively. The circulation time had a major influence on IgG adsorption capacity, but the flow rate had little influence. Experiments in vitro and in vivo confirmed that protein A TFAMC mainly adsorbed Ige and Little of other plasma proteins, and that blood cell damage was negligible. The extracorporeal circulation system is safe and reliable. Copyright (C) 1999 John Wiley & Sons, Ltd.
Resumo:
The phototherapy effects in the skin are related to biomodulation, usually to accelerate wound healing. However, there is no direct proof of the interrelation between the effects of low-level laser therapy (LLLT) and light-emitting diode (LED) in neuropeptide secretion, these substances being prematurely involved in the neurogenic inflammation phase of wound healing. This study therefore focused on investigating LLLT and LED in Calcitonin gene-related peptide (CGRP) and substance P (SP) secretion in healthy rat skin. Forty rats were randomly distributed into five groups with eight rats each: Control Group, Blue LED Group (470 nm, 350 mW power), Red LED Group (660 nm, 350 mW power), Red Laser Group (660 nm, 100 mW power), and Infrared Laser Group (808 nm, 100 mW power) (DMCA (R) Equipamentos Ltda., So Carlos, So Paulo, Brazil). the skin of the animals in the experimental groups was irradiated using the punctual contact technique, with a total energy of 40 J, single dose, standardized at one point in the dorsal region. After 14 min of irradiation, the skin samples were collected for CGRP and SP quantification using western blot analysis. SP was released in Infrared Laser Group (p = 0.01); there was no difference in the CGRP secretion among groups. Infrared (808 nm) LLLT enhances neuropeptide SP secretion in healthy rat skin.
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Background: Ototoxicity is a known side effect of combined radiation therapy and cisplatin chemotherapy for the treatment of medulloblastoma. the delivery of an involved field boost by intensity modulated radiation therapy (IMRT) may reduce the dose to the inner ear when compared with conventional radiotherapy. the dose of cisplatin may also affect the risk of ototoxicity. A retrospective study was performed to evaluate the impact of involved field boost using IMRT and cisplatin dose on the rate of ototoxicity.Methods: Data from 41 medulloblastoma patients treated with IMRT were collected. Overall and disease-free survival rates were calculated by Kaplan-Meier method Hearing function was graded according to toxicity criteria of Pediatric Oncology Group (POG). Doses to inner ear and total cisplatin dose were correlated with hearing function by univariate and multivariate data analysis.Results: After a mean follow-up of 44 months (range: 14 to 72 months), 37 patients remained alive, with two recurrences, both in spine with CSF involvement, resulting in a disease free-survival and overall survival of 85.2% and 90.2%, respectively. Seven patients (17%) experienced POG Grade 3 or 4 toxicity. Cisplatin dose was a significant factor for hearing loss in univariate analysis (p < 0.03). in multivariate analysis, median dose to inner ear was significantly associated with hearing loss (p < 0.01). POG grade 3 and 4 toxicity were uncommon with median doses to the inner ear bellow 42 Gy (p < 0.05) and total cisplatin dose of less than 375 mg/m(2) (p < 0.01).Conclusions: IMRT leads to a low rate of severe ototoxicity. Median radiation dose to auditory apparatus should be kept below 42 Gy. Cisplatin doses should not exceed 375 mg/m(2).
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Background: The issue of unhelpful and harmful therapy outcome has received an increasing amount of attention within the research literature in recent years. However, little research exists on the client's perspective of what constitutes unhelpful therapy. Aim: The aim of this study was to explore clients’ experiences of unhelpful therapy. Method: Semi-structured interviews were carried out with ten therapists who, as clients, experienced unhelpful therapy. Interview transcripts were analysed using interpretative phenomenological analysis. Findings: Participants recounted therapy episodes characterised by an absence of negotiation, collaboration and care; pivotal moments when they knew that they would not return; and ongoing negative effects. Conclusions: The findings of this study have implications for training and strategies for supporting clients who have been harmed by therapy.
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Projeto de Pós-Graduação/Dissertação apresentado à Universidade Fernando Pessoa como parte dos requisitos para obtenção do grau de Mestre em Ciências Farmacêuticas
Resumo:
Projeto de Pós-Graduação/Dissertação apresentado à Universidade Fernando Pessoa como parte dos requisitos para obtenção do grau de Mestre em Ciências Farmacêuticas