• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 206
  • 80
  • 71
  • 24
  • 24
  • 24
  • 24
  • 24
  • 24
  • 15
  • 2
  • 1
  • 1
  • Tagged with
  • 351
  • 351
  • 77
  • 71
  • 66
  • 65
  • 61
  • 60
  • 60
  • 59
  • 47
  • 41
  • 36
  • 34
  • 33
  • 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.
101

The mechanisms of hydroxyurea induced developmental toxicity in the organogenesis stage mouse embryo /

Yan, Jin, 1972- January 2008 (has links)
No description available.
102

Genotoxicity and cytotoxicity of zinc oxide and titanium dioxide in HEp-2 cells

Osman, I. F., Baumgartner, A., Cemeli, E., Fletcher, J. N., Anderson, D. January 2010 (has links)
AIMS: The rapidly growing industrial and medical use of nanomaterials, especially zinc oxide and titanium dioxide, has led to growing concerns about their toxicity. Accordingly, the intrinsic genotoxic and cytotoxic potential of these nanoparticles have been evaluated. MATERIALS & METHODS: Using a HEp-2 cell line, cytotoxicity was tested along with mitochondrial activity and neutral red uptake assays. The genotoxic potential was determined using the Comet and the cytokinesis-blocked micronucleus assays. In addition, tyrosine phosphorylation events were investigated. RESULTS & CONCLUSION: We found concentration- and time-dependent cytotoxicity and an increase in DNA and cytogenetic damage with increasing nanoparticle concentrations. Mainly for zinc oxide, genotoxicity was clearly associated with an increase in tyrosine phosphorylation. Our results suggest that both types of nanoparticles can be genotoxic over a range of concentrations without being cytotoxic.
103

"Jogo patológico e dependência química: correlações entre avidez e regulação emocional" / Pathological gambling and chemical dependence : correlations between craving and emotional states

Santos, Viviane de Castro 09 May 2006 (has links)
Jogo Patológico e Dependência Química são transtornos psiquiátricos que apresentam relevante relação com avidez e estados afetivos. Inevitavelmente, a avaliação destes fenômenos nas dependências químicas sofre o viés da ação farmacológica da substância sobre o humor. Jogo Patológico vem sendo considerado uma dependência comportamental e um modelo promissor na investigação psicológica e contextual de fenômenos presentes nos diagnósticos de dependências. O estudo aprofundado da relação entre avidez e afetos em jogadores patológicos e a comparação dos mesmos com dependentes químicos contribuirá para melhor caracterização do Jogo Patológico e dos tratamentos relacionados / Pathological Gambling (PG) and Chemical Dependence (CD) are psychiatry disorders that have relevant relation with craving and affects. These phenomenons have been investigated in CD, however craving and affects among gamblers did not receive the same attention. Unavoidable, the study of these phenomenons on CD are under the substance related action influence. Craving and affects would be better understood on a disorder that shares the same addictions patterns without the presence of a psycho-active. PG has been described by literature as an addictive behavior. The parallels between Substance Disorders and PG are quite pronounced. PG as a promise model to comprehend the evolving process related to addiction. This investigation might enhance PG clinical characterization and treatment improvement
104

Efeitos pleiotrópicos com reduções equivalentes do LDL-colesterol: estudo comparativo entre sinvastatina e associação sinvastatina/azetimiba / Pleiotropic effects with equivalent LDL-cholesterol reduction: comparative study between simvastatin and simvastatin/ezetimibe coadministration

Araujo, Daniel Branco de 16 August 2007 (has links)
Introdução: A associação de uma estatina com ezetimiba é tão eficaz quanto altas doses da mesma estatina na redução do LDL-colesterol. Os efeitos que não dependem dessa redução são chamados de pleiotrópicos, entre os quais podemos citar: melhora da função endotelial, efeitos anti-oxidantes, efeitos anti- inflamatórios, entre outros. Objetivo: comparar a ação de dois esquemas de tratamento que obtêm reduções equivalentes de LDL-colesterol (sinvastatina 80 mg ao dia e associação sinvastatina 10mg/ezetimiba 10 mg ao dia), sobre os efeitos pleiotrópicos: inflamação, função endotelial e oxidação da LDL. Métodos: estudamos 23 pacientes randomizados e na forma de cross-over 2x2. A inflamação foi mensurada através da PCR-us, a função endotelial por meio de ultra-sonografia e a oxidação de LDL pelas dosagens de LDL eletronegativa (LDL-) e do anticorpo anti-LDL-. Resultados: A redução do LDL-colesterol foi similar nos dois grupos (45,27% no grupo sinvastatina/ezetimiba (p<0,001) e 49,05% no grupo sinvastatina (p<0,001), sem diferença entre os tratamentos (p=0,968)). Os dois grupos apresentaram melhora da função endotelial (3,61% no grupo sinvastatina/ezetimiba (p=0,003) e 5,08% no grupo sinvastatina (p<0,001), não houve diferença entre os tratamentos (p=0,291)). Houve melhora nos níveis da PCR-us (redução de -22,8% no grupo sinvastatina/ezetimiba (p=0,004) e de 29,69% no grupo sinvastatina (p=0,01), sem diferenças entre os tratamentos (p=0,380)). Não houve redução significativa da LDL-. Ocorreu aumento na concentração do anticorpo anti-LDL eletronegativa apenas no grupo sinvastatina (p=0,045). Conclusões: as duas formas de tratamento são eficazes na melhora da função endotelial e dos níveis de PCR-us. Somente com o uso da sinvastatina em alta dose houve aumento nos níveis de anticorpos anti-LDL-. / Introduction: The co-administration of a statin with ezetimibe is as effective as high doses of the same statin in the reduction of the LDL-cholesterol. The effects which don´t depend of this reduction are called pleiotropic effects, some among them can be cited: endothelial function improvement, antioxidative and anti-inflammatory effects. Objective: compare the effectiveness of these two different treatments that obtain equivalent reductions of LDLcholesterol (simvastatin 80 mg once a day and co-administration of simvastatin 10 mg once a day and ezetimibe 10 mg once a day), about pleiotropic effects: inflammation, endothelial function and LDL oxidation. Methods: we have studied 23 randomized patients in a 2x2 cross-over study. Inflammation was measured by high-sensitive C reactive protein, endothelial function by echocardiography and LDL oxidation by electronegative LDL and electronegative anti-LDL antibodies levels. Results: the LDL-cholesterol was similar between the two groups (45,27% reduction in the simvastatin/ezetimibe group (p<0,001) and 49,05% reduction in the simvastatin group (p<0,001); no difference between treatments was found (p=0,968). The two groups had improvement in endothelial function (3,61% in the simvastatin/ezetimibe group (p=0,003) and 5,08% in the simvastatin group (p<0,001)), no differences was found between the two groups (p=0,291). High-sensitive C reactive protein had a 22,8% reduction in the simvastatin/ezetimiba group (p=0,004) and 29,69% reduction in the simvastatin group (p=0,01), with no significative difference in any of the two treatments (p=0,380). There was no significative difference in LDL- levels. The anti-LDL- antibodies concentration was increased only in the simvastatin group (p=0,045). Conclusion: the two forms of treatments presented some similar pleiotropic effects - improvement in endothelial function and decreased hs-CRP levels. Only with a high simvastatim dose the anti-LDL- antibodies concentration was increased.
105

Effects of basic fibroblast growth factor and platelet-derived growth factor isoform B in tendon healing--: in vitro and in vivo models in rat patellar tendon. / CUHK electronic theses & dissertations collection

January 1998 (has links)
by Chan Pui, Barbara. / Thesis (Ph.D.)--Chinese University of Hong Kong, 1998. / Includes bibliographical references (p. 137-151). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Mode of access: World Wide Web. / Abstracts in English and Chinese.
106

Efeitos pleiotrópicos com reduções equivalentes do LDL-colesterol: estudo comparativo entre sinvastatina e associação sinvastatina/azetimiba / Pleiotropic effects with equivalent LDL-cholesterol reduction: comparative study between simvastatin and simvastatin/ezetimibe coadministration

Daniel Branco de Araujo 16 August 2007 (has links)
Introdução: A associação de uma estatina com ezetimiba é tão eficaz quanto altas doses da mesma estatina na redução do LDL-colesterol. Os efeitos que não dependem dessa redução são chamados de pleiotrópicos, entre os quais podemos citar: melhora da função endotelial, efeitos anti-oxidantes, efeitos anti- inflamatórios, entre outros. Objetivo: comparar a ação de dois esquemas de tratamento que obtêm reduções equivalentes de LDL-colesterol (sinvastatina 80 mg ao dia e associação sinvastatina 10mg/ezetimiba 10 mg ao dia), sobre os efeitos pleiotrópicos: inflamação, função endotelial e oxidação da LDL. Métodos: estudamos 23 pacientes randomizados e na forma de cross-over 2x2. A inflamação foi mensurada através da PCR-us, a função endotelial por meio de ultra-sonografia e a oxidação de LDL pelas dosagens de LDL eletronegativa (LDL-) e do anticorpo anti-LDL-. Resultados: A redução do LDL-colesterol foi similar nos dois grupos (45,27% no grupo sinvastatina/ezetimiba (p<0,001) e 49,05% no grupo sinvastatina (p<0,001), sem diferença entre os tratamentos (p=0,968)). Os dois grupos apresentaram melhora da função endotelial (3,61% no grupo sinvastatina/ezetimiba (p=0,003) e 5,08% no grupo sinvastatina (p<0,001), não houve diferença entre os tratamentos (p=0,291)). Houve melhora nos níveis da PCR-us (redução de -22,8% no grupo sinvastatina/ezetimiba (p=0,004) e de 29,69% no grupo sinvastatina (p=0,01), sem diferenças entre os tratamentos (p=0,380)). Não houve redução significativa da LDL-. Ocorreu aumento na concentração do anticorpo anti-LDL eletronegativa apenas no grupo sinvastatina (p=0,045). Conclusões: as duas formas de tratamento são eficazes na melhora da função endotelial e dos níveis de PCR-us. Somente com o uso da sinvastatina em alta dose houve aumento nos níveis de anticorpos anti-LDL-. / Introduction: The co-administration of a statin with ezetimibe is as effective as high doses of the same statin in the reduction of the LDL-cholesterol. The effects which don´t depend of this reduction are called pleiotropic effects, some among them can be cited: endothelial function improvement, antioxidative and anti-inflammatory effects. Objective: compare the effectiveness of these two different treatments that obtain equivalent reductions of LDLcholesterol (simvastatin 80 mg once a day and co-administration of simvastatin 10 mg once a day and ezetimibe 10 mg once a day), about pleiotropic effects: inflammation, endothelial function and LDL oxidation. Methods: we have studied 23 randomized patients in a 2x2 cross-over study. Inflammation was measured by high-sensitive C reactive protein, endothelial function by echocardiography and LDL oxidation by electronegative LDL and electronegative anti-LDL antibodies levels. Results: the LDL-cholesterol was similar between the two groups (45,27% reduction in the simvastatin/ezetimibe group (p<0,001) and 49,05% reduction in the simvastatin group (p<0,001); no difference between treatments was found (p=0,968). The two groups had improvement in endothelial function (3,61% in the simvastatin/ezetimibe group (p=0,003) and 5,08% in the simvastatin group (p<0,001)), no differences was found between the two groups (p=0,291). High-sensitive C reactive protein had a 22,8% reduction in the simvastatin/ezetimiba group (p=0,004) and 29,69% reduction in the simvastatin group (p=0,01), with no significative difference in any of the two treatments (p=0,380). There was no significative difference in LDL- levels. The anti-LDL- antibodies concentration was increased only in the simvastatin group (p=0,045). Conclusion: the two forms of treatments presented some similar pleiotropic effects - improvement in endothelial function and decreased hs-CRP levels. Only with a high simvastatim dose the anti-LDL- antibodies concentration was increased.
107

"Jogo patológico e dependência química: correlações entre avidez e regulação emocional" / Pathological gambling and chemical dependence : correlations between craving and emotional states

Viviane de Castro Santos 09 May 2006 (has links)
Jogo Patológico e Dependência Química são transtornos psiquiátricos que apresentam relevante relação com avidez e estados afetivos. Inevitavelmente, a avaliação destes fenômenos nas dependências químicas sofre o viés da ação farmacológica da substância sobre o humor. Jogo Patológico vem sendo considerado uma dependência comportamental e um modelo promissor na investigação psicológica e contextual de fenômenos presentes nos diagnósticos de dependências. O estudo aprofundado da relação entre avidez e afetos em jogadores patológicos e a comparação dos mesmos com dependentes químicos contribuirá para melhor caracterização do Jogo Patológico e dos tratamentos relacionados / Pathological Gambling (PG) and Chemical Dependence (CD) are psychiatry disorders that have relevant relation with craving and affects. These phenomenons have been investigated in CD, however craving and affects among gamblers did not receive the same attention. Unavoidable, the study of these phenomenons on CD are under the substance related action influence. Craving and affects would be better understood on a disorder that shares the same addictions patterns without the presence of a psycho-active. PG has been described by literature as an addictive behavior. The parallels between Substance Disorders and PG are quite pronounced. PG as a promise model to comprehend the evolving process related to addiction. This investigation might enhance PG clinical characterization and treatment improvement
108

Interaction between tin/flouride-containing solutions and artificially created dental pellicles on erosion prevetion in vitro

Algarni, Amnah Abdullah A. January 2013 (has links)
Indiana University-Purdue University Indianapolis (IUPUI)School of dentistry / BACKGROUND: Fluoride and stannous ions have been reported to be relevant for dental erosion prevention. However, their interaction with the acquired dental pellicle (ADP), a clinically relevant erosion protective factor, is not well known and needs to be investigated. OBJECTIVES: To investigate the anti-erosive properties of fluoride-containing solutions and stannous solutions on enamel and dentin surfaces with a previously formed ADP. To characterize the protein profile of the ADP treated with the test solutions. METHODS: Phase I tested four solutions: SnCl2/NaF, NaF, SnCl2 and deionized water (DIW) (as negative control). Forty bovine enamel and dentin specimens 104 (4x4x2 mm3) were prepared and randomly distributed into 4 groups (n = 10). The specimens were incubated in clarified human saliva (CHS) for 24 h for pellicle formation and then they were subjected to a cycling procedure that included a 5-min erosive challenge (0.3-percent citric acid, pH 2.6); a 2-min treatment with the solution (between 1st, 3rd and 6th cycles); a 2-h immersion in CHS, and overnight immersion in CHS. Cycles were repeated 6x/day for 5 days. The outcome measure was surface loss (SL) using profilometry. Phase II: Thirty-two (32) bovine enamel specimens (882 mm3) (n = 8) were similarly prepared and incubated in saliva for 24 h and then treated with the solutions for 2 min followed by CHS immersion for 2 h. This cycle was repeated 3x for one day. The pellicles formed and treated with the test rinse solutions were collected, digested, and analyzed for specific protein content using liquid chromatography electrospray ionization tandem mass spectrometry (LCESI-MS/MS). RESULTS: Phase I: for enamel, SnCl2/NaF, SnCl2, NaF solutions provided 89 percent, 67 percent, and 42 percent SL reduction respectively compared with the control, while in dentin they provided 60 percent, 23 percent, and 36 percent, respectively, all significant at p < 0.05. Phase II: Seventy-two (72) common proteins were identified in all groups, 30 exclusive to DIW, 20 to SnCl2/NaF, 19 to NaF, and 13 to SnCl2. SnCl2/NaF increased the abundance of pellicle proteins than each one alone. CONCLUSION: SnCl2/NaF showed the best anti-erosive effect on both enamel and dentin. The findings suggest that the composition of acquired pellicle changes with different solutions, which may be related to their anti-erosive effect.
109

The Responses of Human Neutrophils to Tobacco Smoke Components

Al-Shibani, Nouf Khider January 2012 (has links)
Indiana University-Purdue University Indianapolis (IUPUI) / Tobacco smoking is considered a major modifiable risk factor for periodontal disease. Tobacco contains about 6700 compounds and almost 4000 compounds of these have been identified in tobacco smoke. Nicotine is the addictive ingredient in tobacco and has been shown to affect multiple cellular processes. Cigarette smoke condensate (CSC) is the particulate matter of smoke. It is believed to be a powerful inducer of inflammatory responses. Neutrophils are the first line of host defense and are critical cells in the maintenance of periodontal health through their role in the control of bacteria, but they can also contribute to the progression of periodontal disease by the production and release of reactive oxygen species (ROS). Virulence factors from periodontal pathogens, such as Porphyromonas gingivalis (P. gingivalis), stimulate the respiratory burst of neutrophils. In this dissertation, three studies aimed at understanding the oxidative activity of neutrophils when stimulated with either nicotine, cigarette smoke condensate (CSC) or four other components of tobacco smoke (2-naphthylamine, hydroquinone, acrolein, and acetaldehyde) with or without P. gingivalis supernatant. The release of matrix metalloproteinase-9 (MMP-9) was also examined. ROS production increased significantly when the neutrophils were stimulated with nicotine. P. gingivalis induced the maximum ROS production when compared to all the other components examined. The combination of nicotine and P. gingivalis did not have an additive effect on ROS production. Nicotine significantly increased the MMP-9 release from the neutrophils. On the contrary, CSC inhibited ROS production at all the concentrations examined. The combination of CSC and P. gingivalis resulted in the inhibition of ROS production. MMP-9 release was also increased from the CSC-treated neutrophils. The four other tobacco smoke components examined affected ROS production and MMP-9 release differently. These projects demonstrated that CSC inhibited the ROS production from neutrophils, which can be attributed to several components in tobacco smoke that may include acrolein and hydroquinone. More research is needed to determine the mechanisms of inhibition and if other tobacco components are involved in ROS inhibition
110

"Flutuação da atenção na doença de Parkinson" / Fluctuation of attention in Parkinson's disease

Corrêa Neto, Ylmar 31 March 2006 (has links)
Para avaliar a influencia em curto prazo da reposição dopaminérgica na flutuação da atenção em pacientes com DP, a latência média e o desvio-padrão da latência do tempo de reação simples e com escolha foram estabelecidos em 15 pacientes com DP antes e 90 minutos depois da administração da dose habitual matutina de levodopa e em 15 controles normais. Verificou-se , além de efeitos motores, maior sincronia nas latências de testes de tempo de reação complexos, mas não nos simples, sugerindo efeitos da dopamina em mecanismos atencionais e/ou de controle executivo que envolvam flexibilidade na identificação do estímulo e/ou na escolha da resposta / To evaluate short time effects of dopaminergic medication on fluctuation of attention in PD patients, simple and choice reaction latency and latency standard deviation was determined in 15 PD patients before and 90 min. after usual early morning levodopa dose and in 15 normal controls. Besides motor improvement, improved synchrony on complex but not on simple reaction time tests was observed, suggesting dopamine attention and executive control modulation, probably thru stimulus identification and action selection flexibility

Page generated in 0.0552 seconds