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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

A computer-guided robotic panretinal laser photocoagulation system

Sarnel, Haldun January 1994 (has links)
No description available.
2

The evaluation of Port Wine Stain Haemangioma before and after treatment by pulsed dye laser

Smart, J. R. January 1986 (has links)
No description available.
3

A study on nanocomposite hydroxyapatite coatings on Ti6Al4V fabricated by electrophoretic deposition and laser surface treatment

Zhang, Bo Kai January 2011 (has links)
University of Macau / Faculty of Science and Technology / Department of Electromechanical Engineering
4

Avaliação da efetividade do laser terapêutico no controle de índice de dor de pacientes em tratamento ortodôntico /

Martins, Isabela Parsekian. January 2011 (has links)
Orientador: Ary dos Santos Pinto / Banca: Luiz Gonzaga Gandini Junior / Banca: Ana Claudia Moreira de Melo / Resumo: O objetivo deste estudo foi avaliar a aplicação do laser diodo AsGaAl no controle da sensação dolorosa de paciente em procedimento de separação dental dos 1os molares inferiores. Participaram da pesquisa 62 pacientes com idade média de 19,7 anos que iniciaram o tratamento ortodôntico na Clínica de Pós-Graduação da Disciplina de Ortodontia do Departamento de Clínica Infantil da Faculdade de Odontologia de Araraquara - UNESP. Os pacientes foram divididos em 4 grupos alternando a aplicação do laser com e sem efeito terapêutico e de acordo com rodízio do lado do início de sua aplicação: GrupoI- Início laser lado direito; Grupo II- Início placebo lado direito; Grupo III- Início laser lado esquerdo Grupo IV -Início placebo lado esquerdo. O laser, com ou sem efeito terapêutico, foi aplicado antes da separação, 24 e 48 horas após a separação. A dor foi avaliada por uma escala visual analógica. O índice de dor foi registrado antes e após a aplicação do laser com ou sem efeito terapêutico dependendo do grupo, e imediatamente após a separação. Após 24 e 48 horas, o registro da dor se deu antes e após as aplicações de laser com ou sem efeito terapêutico dependendo do grupo. Antes e após a irradiação, a média dos escores da EVA para o grupo placebo e laser foi de zero. Logo após a separação, a média da EVA para o grupo placebo foi de 1,6, significantemente maior que a média de 1,1 registrada para o grupo laser 17 (p=0,013). Após 24 horas e antes da nova irradiação, os valores de dor registrados entre os grupos não se mostraram diferentes, com valores de 2,6 e 2,2 para os grupos placebo e laser, respectivamente. Após a irradiação, os valores caíram para 1,8 e 1,6 não se mostrando diferentes. Após 48 horas, os valores... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The objective of this research was to compare the effect single low-level laser therapy (LLLT) irradiation on pain perception in patients having fixed appliance treatment in the clinic of postgraduate discipline Orthodontics Department, Araraquara-UNESP. Sixty-two patients with mean age, 19.7 years, were recruited to participate in this randomized, double-blinded, placebo-controlled study. The pacients were assigned to 4 groups: Group I- Laser on the right side; Group II- Placebo on the right side; Group III- Laser on the left side; Group IV- Placebo on the left. The laser or placebo was applied before separation, 24 and 48 hours after separation of their first permanent molars in the lower arch. The pain was recorded by a visual analog scale. The data of the pain's scale was recorded before and after the laser's or placebo's irradiation depending on the group, and immediately after separation and then after 24 and 48 hours. Before and after irradiation, the average of the scores of EVA to the placebo group and laser was zero. Just after the separation, the average of the EVA for the placebo group was 1.6, significantly greater than the average of 1.1 registered for the laser Group (p = 0.013). After 24 hours and before the new irradiation, the values registered among the different groups did not show any diferences, with values from 2.2 to 2.6 and placebo groups and laser, respectively. After irradiation, the values dropped to 1.8 and 1.6 not showing 19 differences. After 48 hours, the values continued dropping without any differences. In relation to the gender, only after the first irradiation in placebo group, the female had a level of pain (0.1) significantly higher (p = 0.04) compared to male, and after 48 hours, the group where the laser was applied had a difference (p = 0.04) among the gender with a value of lower pain... (Complete abstract click electronic access below) / Mestre
5

Estudo dosimétrico do efeito do laser de baixa potência na mucosite oral induzida por 5-Fluorouracil em hamsters / Dosimetric study of Low Level Laser Therapy in oral mucositis induced by 5-Fluorouracil in hamsters

Cotomácio, Cláudia Carrara 28 September 2016 (has links)
A Mucosite Oral (MO) é uma consequência debilitante do tratamento oncológico, que pode ser tratada com o uso do laser de baixa potência (LBP). Entretanto, ainda não há consenso na literatura a respeito de parâmetros dosimétricos para o reparo da mucosa oral. Dessa forma, o objetivo do estudo foi comparar diferentes protocolos com laser de baixa potência (FLBP) para o tratamento da MO, através de análises clínicas e histológicas. Quinze hamsters foram usados, em um modelo de indução de MO por 5-Fluorouracil (5-FU) e ranhuras superficiais na mucosa oral, com 7 dias de acompanhamento clínico. Os animais foram divididos em cinco grupos: Controle (C), que recebeu apenas anestesia e o veículo do quimioterápico, Controle-Quimioterapia (CQ) que recebeu anestesia, 5-FU e ranhuras, Laser Protocolo 1 (L1) que recebeu o mesmo do grupo CQ + FLBP 6 J/cm²/0,24 J (um ponto), Laser Protocolo 2 (L2) o mesmo do grupo CQ + FLBP 25 J/cm²/1 J (um ponto) e Laser Protocolo 3 (L3), o mesmo do grupo CQ + FLBP 6 J/cm²/0,96 J (4 pontos de 0,24J). O laser foi utilizado em ?=660 nm, com área do spot de 0,04 cm² e 40 mW de potência. O melhor protocolo de FLBP para manter os graus de MO mais baixos, em relação ao grupo CQ, foi o L1, seguido dos protocolos L2 e L3. Os resultados histológicos demonstraram padrão semelhante entre os grupos L1, L2 e C, com alguns vasos sanguíneos e a presença de um fino epitélio de aspecto contínuo no dia 7. Nossos resultados sugerem que o modo de aplicação do LBP e a energia entregue por área pode interferir na reparação da MO. / Oral mucositis (OM) is a dose-limited debilitating consequence from cancer treatment that could be treated with low level laser therapy (LLLT); however, there is no consensus about its dosimetric parameters for oral mucosa healing. Thus, the aim of this study is to compare different LLLT protocols on the treatment of OM, through clinical and histological analysis. Fifteen hamsters were used, in an induced model of OM by 5-Fluorouracil (5-FU) and superficial scratching in oral mucosa, in seven days of follow-up. The animals were divided into 5 groups: Control (C) which received only anesthesia and chemotherapic vehicle; Control-Chemotherapy (Ch) which received anesthesia, 5-FU and scratches; Laser Protocol 1 (L1) the same as Ch group + LLLT 6 J/cm²/0.24J (one point); Laser Protocol 2 (L2) the same as Ch group + LLLT 25J/cm²/1J (one point); and Laser Protocol 3 (L3) the same as Ch group + LLLT 6 J/cm²/0.96 J (4 points of 0.24J). The laser that was used has ?=660 nm, 0.04 cm² of spot area and 40 mW of power. The best LLLT protocol to maintain lowest OM levels compared to Ch group was L1, followed by L2 and L3. Histological results demonstrated a similar pattern among L1, L2 and C groups, with some blood vessels presence and continuous aspect of a thin epithelium, on day 7. Our results suggest that the application mode of LLLT and the energy delivered per area could interfere in the oral mucositis healing.
6

Estudo dosimétrico do efeito do laser de baixa potência na mucosite oral induzida por 5-Fluorouracil em hamsters / Dosimetric study of Low Level Laser Therapy in oral mucositis induced by 5-Fluorouracil in hamsters

Cláudia Carrara Cotomácio 28 September 2016 (has links)
A Mucosite Oral (MO) é uma consequência debilitante do tratamento oncológico, que pode ser tratada com o uso do laser de baixa potência (LBP). Entretanto, ainda não há consenso na literatura a respeito de parâmetros dosimétricos para o reparo da mucosa oral. Dessa forma, o objetivo do estudo foi comparar diferentes protocolos com laser de baixa potência (FLBP) para o tratamento da MO, através de análises clínicas e histológicas. Quinze hamsters foram usados, em um modelo de indução de MO por 5-Fluorouracil (5-FU) e ranhuras superficiais na mucosa oral, com 7 dias de acompanhamento clínico. Os animais foram divididos em cinco grupos: Controle (C), que recebeu apenas anestesia e o veículo do quimioterápico, Controle-Quimioterapia (CQ) que recebeu anestesia, 5-FU e ranhuras, Laser Protocolo 1 (L1) que recebeu o mesmo do grupo CQ + FLBP 6 J/cm²/0,24 J (um ponto), Laser Protocolo 2 (L2) o mesmo do grupo CQ + FLBP 25 J/cm²/1 J (um ponto) e Laser Protocolo 3 (L3), o mesmo do grupo CQ + FLBP 6 J/cm²/0,96 J (4 pontos de 0,24J). O laser foi utilizado em ?=660 nm, com área do spot de 0,04 cm² e 40 mW de potência. O melhor protocolo de FLBP para manter os graus de MO mais baixos, em relação ao grupo CQ, foi o L1, seguido dos protocolos L2 e L3. Os resultados histológicos demonstraram padrão semelhante entre os grupos L1, L2 e C, com alguns vasos sanguíneos e a presença de um fino epitélio de aspecto contínuo no dia 7. Nossos resultados sugerem que o modo de aplicação do LBP e a energia entregue por área pode interferir na reparação da MO. / Oral mucositis (OM) is a dose-limited debilitating consequence from cancer treatment that could be treated with low level laser therapy (LLLT); however, there is no consensus about its dosimetric parameters for oral mucosa healing. Thus, the aim of this study is to compare different LLLT protocols on the treatment of OM, through clinical and histological analysis. Fifteen hamsters were used, in an induced model of OM by 5-Fluorouracil (5-FU) and superficial scratching in oral mucosa, in seven days of follow-up. The animals were divided into 5 groups: Control (C) which received only anesthesia and chemotherapic vehicle; Control-Chemotherapy (Ch) which received anesthesia, 5-FU and scratches; Laser Protocol 1 (L1) the same as Ch group + LLLT 6 J/cm²/0.24J (one point); Laser Protocol 2 (L2) the same as Ch group + LLLT 25J/cm²/1J (one point); and Laser Protocol 3 (L3) the same as Ch group + LLLT 6 J/cm²/0.96 J (4 points of 0.24J). The laser that was used has ?=660 nm, 0.04 cm² of spot area and 40 mW of power. The best LLLT protocol to maintain lowest OM levels compared to Ch group was L1, followed by L2 and L3. Histological results demonstrated a similar pattern among L1, L2 and C groups, with some blood vessels presence and continuous aspect of a thin epithelium, on day 7. Our results suggest that the application mode of LLLT and the energy delivered per area could interfere in the oral mucositis healing.
7

Nanoparticle-mediated photothermal therapy of tumors : a comparative study of heating efficiencies for different particle types

Pattani, Varun Paresh 08 November 2010 (has links)
Cancer is one of the most notorious diseases affecting the human population today with very few effective treatments. Due to the disparate nature of cancers, it is difficult to obtain a treatment that can cure cancer. Thus, there is a large influx of research towards cancer therapies, leading to one of the discovery that cancer cells (tumors) have a low thermotolerance in comparison to normal cells. If the temperature of the cancer cells is increased into the hyperthermia range (~45°C) thermal damage occurs, causing cell death by protein denaturation and membrane disruption. A recent development in this field has been in the photothermal treatment of tumors, which is starting to utilize plasmonic particles to enhance the specificity of the treatment. The plasmonic nanoparticles, specifically gold, can reach the tumor site using passive targeting and when irradiated with a tuned laser will emit heat localized to a small region around the nanoparticle killing the surrounding cancer cells. This process has been shown to reduce tumor size in vivo with gold nanoshells and gold nanorods. However, it has not been shown which particle is better at delivering the heat to the tumor site. Therefore in this study, it will be shown which particle generates the most heat. Solutions of tissue simulating phantom and different concentrations of nanoparticles were irradiated with a laser to measure the increase in temperature. Additionally, simulations were performed using Mie Theory for nanoshells and the Discrete Dipole Approximation for nanorods. Based on the physical parameters of the nanoshells and nanorods used in this experiment, the adjusted absorption cross-section was determined. It was found that nanoshells generated the most amount of heat on a per particle basis, and that it was necessary to have a nanorod concentration of 5.5 times the concentration of nanoshells to generate the same amount of heat as nanoshells. These results were confirmed using Monte Carlo and Finite Difference Modeling of the nanoparticle heating experiments. However, the choice of nanoparticle still depends on the application and the targeting efficiency in vivo. / text
8

Influência do laser em baixa intensidade (660 nm) no processo de reparo de feridas cutâneas provocadas em ratos tratados com nicotina : estudo histológico /

Macarimi, Valmir Campos. January 2004 (has links)
Orientador: Valdir Gouveia Garcia / Reumo: A proposta do presente estudo foi avaliar, histologicamente a influência da terapia do laser em baixa intensidade (LLLT)) sobre o processo de reparo em feridas cutâneas provocadas no dorso de ratos tratados com nicotina. Foram utilizados 115 ratos neste estudo. Cinqüenta e nove ratos receberam injeção subcutânea de solução salina (0,2 ml), enquanto o restante dos animais receberam injeção subcutânea de nicotina (3mg/Kg de peso do animal), duas vezes ao dia durante todo o período experimental. Decorridos 30 dias das aplicações, foi criada uma ferida cirúrgica sobre o dorso de cada animal por meio de um punch ( 8 mm de diâmetro). Os animais que receberam solução salina foram divididos em 2 grupos: Grupo I(Controle)(n=29) - As feridas permaneceram sem nenhum tratamento enquanto as do Grupo II (n=30) foram submetidas a tratamento com LLLT (AlGaAs)660 nm, 40 mW, 3.0 J, 0,56 w/cm2). Os animais que receberam injeção subcutânea de nicotina também foram divididos em 2 grupos. Grupo III (n=29) onde as feridas não receberam nenhum tratamento; e Grupo IV (n=27), no qual os animais receberam tratamento com LLLT (660 nm, 40 mW, 3,0 J, 0,56 W/cm2). Cada...(Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The purpose of this study was to histologically analyze the influence of low level laser therapy (LLLT) on the healing process of surgically created coetaneous wounds in rats treated with nicotine. One hundred and fifteen rats were used in this study. Fifty nine rats received subcutaneous injection of saline (0,2 ml) while the remaining animals received subcutaneous injection of nicotine (3 mg/kg of body weight) twice a day during all experimental period. After 30 days of either saline or nicotine injection, coetaneous wounds were surgically created on the back of the animals with a punch (8 mm in diameter). The animals that received saline injections were divided into 2 groups: Group I (control) (n= 29) - The wound was left untreated; and Group II (n= 30) - The wound was treated with LLLT (GaAlAs 660 nm, 40 mW, 3.0 J, 0.56 W/cm2). The animals that received nicotine injections were also divided into 2 groups: Group III (n= 29) - The wound was left untreated; and Group IV (n= 27) - The wound was treated with LLLT (GaAlAs 660 nm, 40 mW, 3.0 J, 0.56 W/cm2). Each group was subdivided into sub-groups for euthanasia at either 3, 7 or 14 days post-operative. Block sections were routinely processed for histological analysis using H&E stain. Group III showed delayed epithelial migration and connective tissue organization when compared to Group I. The wounds of Group II presented an...(Complete abstract, click electronic access below) / Mestre
9

Physical activity, vascular risk and cognitive performance in young adults

Hwang, Jungyun 04 September 2015 (has links)
A growing body of literature suggests that higher levels of physical activity and cardiorespiratory fitness, as well as an alternative treatment such as low level laser therapy (LLLT), have beneficial effects on cognition, while sedentary lifestyle-induced obesity and vascular risk negatively influence cognition. However, the relationship between cardiorespiratory fitness and vascular risk on cognitive function and the effect of an acute bout of very vigorous aerobic exercise (acute exercise) on cognitive performance has not yet been investigated. Additionally, the effects of combined acute exercise and LLLT treatments on cognitive performance have not yet been characterized. Therefore, the goal of this dissertation was to conduct a series of three research studies ranging from a cross-sectional exploratory study about the association of cardiorespiratory fitness, obesity, and vascular risk on cognitive function, to an experimentally designed study that compared the effects of acute exercise, LLLT, and the combination of these two treatments on cognitive performance in young adults. Study1 examined the relationship among cardiorespiratory fitness (maximal oxygen consumption, VO2max), obesity indices (body mass index, BMI; waist circumstance), and vascular risk (C-reactive protein; CRP). Cognitive function included crystalized intelligence (Kaufman Brief Intelligence Test; KBIT), executive functions of inhibition (Stroop test), switching (Trail making test; TMT), attention (Psychomotor Vigilance Task; PVT), and working memory (Delayed-Match-to-Sample, DMS). Study 2 determined the effect of acute exercise on cognitive performance including executive response inhibition (Stroop test) and response switching (TMT) and brain-derived neurotrophic factor (BNDF). Study 3 compared the effectiveness of LLLT and acute exercise on cognitive performance, which included attention (PVT) and working memory (DMS). Results demonstrated there was a beneficial effect of physical exercise-induced improvements in cardiorespiratory fitness on vascular risk and cognitive functions particularly in working memory and inhibitory control (Study1). Acute exercise improved performance in inhibitory control and increased the BNDF level compared to the control condition, suggesting the acute exercise-induced the increase in BDNF level may be at least in part of mediating the cognitive performance improvement (Study 2). All three conditions (acute exercise, LLLT, or the combination) improved performance in attention and working memory, as measured by reaction time and response accuracy, when compared to a control group. Specially, the combined group showed a trend of greater improvement in attention and worming memory performance (Study 3). Taken together, the results of this research series suggest that acute exercise and LLLT can improve cognitive performance, which is also mediated by health indices including cardiorespiratory fitness, obesity, and vascular risk. It is anticipated that these findings will make substantive contributions to the empirical literature concerning the beneficial effect of exercise and LLLT on cognitive health in young adults, given the current paucity of research. / text
10

Wirkung fraktional ablativer Lasersysteme in der Therapie der gealterten und chronisch lichtgeschädigten Haut

Möbius, Anne 12 December 2013 (has links) (PDF)
In der vorliegenden Arbeit wurde mit einer Vielzahl an objektiven Messverfahren und subjektiven Einschätzungen, die Wirkungen und Nebenwirkungen von drei unterschiedlichen fraktional ablativen Lasersystemen in der Therapie der gealterten und chronisch lichtgeschädigten Haut einzelner Gesichtsareale, sowie des gesamten Gesichtes dargestellt: CO 2 -Laser; Er:YAG hot Laser; Er:YAG cold Laser. Dabei kamen profilometrische Messungen, Messung von Hautfunktionsparameter (Elastizität, Feuchtigkeit, Sebumgehalt), Bewertungen von Fotografien und Fragebögen zur Erfassungs des Wirkungsprofils einer Lasertherapie zur Anwendung.

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