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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.
791

Mechanistic understanding of oral drug absorption enhancement of cromolyn sodium by an amino acid derivitive

Alani, Adam Wathah Ghassan. January 2007 (has links)
Thesis (Ph. D.)--University of Wisconsin--Madison, 2007. / eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (p. 149-160).
792

Cleanup of internal filter cake during flowback

Suri, Ajay, January 1900 (has links) (PDF)
Thesis (Ph. D.)--University of Texas at Austin, 2005. / Vita. Includes bibliographical references.
793

Increased-throughput screening of potential drug candidates for permeation across membranes and estimation of central nervous system bioavailability

Braddy, April C., January 2004 (has links)
Thesis (Ph.D.)--University of Florida, 2004. / Typescript. Title from title page of source document. Document formatted into pages; contains 167 pages. Includes Vita. Includes bibliographical references.
794

Modulation of coronary and skeletal muscle exchange by adenosine : role of adenosine receptors /

Wang, Jianjie, January 2005 (has links)
Thesis (Ph. D.)--University of Missouri--Columbia, 2005. / "July 2005." Typescript. Vita. Includes bibliographical references (leaves 196-211). Also issued on the Internet.
795

Mechanistic understanding of oral drug absorption enhancement of cromolyn sodium by an amino acid derivitive /

Alani, Adam Wathah Ghassan. January 2007 (has links)
Thesis (Ph. D.)--University of Wisconsin--Madison, 2007. / Includes bibliographical references (p. 149-160). Also available on the Internet.
796

A close-up on neutrophils : Visualizing the mechanisms of their in vivo recruitment and function

Massena, Sara January 2015 (has links)
A successful immune response depends on prompt and sufficient recruitment of leukocytes from the circulation to infected or injured sites. Mobilization of leukocytes to hypoxic tissues is vital for angiogenesis, i.e. the formation of new blood vessels from preexisting vasculature, and thus crucial for tissue growth and regeneration. Deviations from normal leukocyte recruitment drive a variety of pathologies, including chronic inflammation, autoimmune diseases and cancer, for which therapeutic options are limited or unspecific. Understanding the mechanisms by which the body controls leukocyte recruitment is therefore critical for the development of novel therapeutic strategies. The present investigations focused on delineating the mechanisms behind leukocyte mobilization from the bloodstream to afflicted sites, by means of in vivo imaging techniques and in vitro assays. We demonstrate that, in response to inflammation, increased vascular permeability enhances transendothelial transport of tissue-released chemokines. Within the vasculature, chemokines form a chemotactic gradient sequestered on heparan sulfate, which directs crawling neutrophils and expedites their extravasation to the inflamed tissue. Consequently, gradient formation grants efficient bacterial clearance. Citrullination of chemokines by leukocyte-derived PAD enzymes in the inflamed tissue prevents chemokine transport into blood vessels, which dampens further neutrophil recruitment and thereby controls the amplitude of the inflammatory response. Moreover, the mechanisms of neutrophil recruitment in response to proangiogenic factors released during hypoxia are revealed to differ from those observed during classical inflammation. Particularly, VLA-4 integrin and VEGFR1 expressed on a defined subset of neutrophils, along with endothelial VEGFR2, are required for efficient neutrophil recruitment to hypoxia. Rather than stimulus-induced phenotypic changes on neutrophils, specific neutrophil subtypes with innate proinflammatory or proangiogenic functions (respectively, CD49d-VEGFR1lowCXCR4low and CD49d+VEGFR1highCXCR4high) coexist in the circulation of humans and mice. In summary, this dissertation provides relevant information on specific steps of neutrophil recruitment to inflamed or hypoxic tissues, which may represent future means to down-regulate aberrant immune responses during chronic inflammation and autoimmune diseases; to increase angiogenesis during ischemia; or to limit pathological angiogenesis, a characteristic of tumor growth and of several chronic inflammatory disorders.
797

Efeito da associação de fosfato de cálcio, laser Nd:YAG e adesivo na permeabilidade dentinária e na resistência de união / Effect of the association of calcium phosphate, Nd:YAG laser and adhesive on dentin permeability and bond strength

Benitez Sellan, Pablo Lenin 11 December 2017 (has links)
Submitted by PABLO LENIN BENITEZ SELLAN null (drpablobens@gmail.com) on 2017-12-14T18:23:53Z No. of bitstreams: 1 Dissertação Pablo Benitez Mestrado Dentistica.pdf: 11665620 bytes, checksum: 383da8829341bad52fdb34ed88ead959 (MD5) / Approved for entry into archive by Silvana Alvarez null (silvana@ict.unesp.br) on 2017-12-18T15:13:01Z (GMT) No. of bitstreams: 1 benitezsellan_pl_me_sjc.pdf: 11665620 bytes, checksum: 383da8829341bad52fdb34ed88ead959 (MD5) / Made available in DSpace on 2017-12-18T15:13:01Z (GMT). No. of bitstreams: 1 benitezsellan_pl_me_sjc.pdf: 11665620 bytes, checksum: 383da8829341bad52fdb34ed88ead959 (MD5) Previous issue date: 2017-12-11 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / O objetivo deste estudo foi avaliar in vitro o efeito do tratamento com a associação de fosfato de cálcio, laser de Nd:YAG e sistema adesivo na permeabilidade dentinária e na resistência de união. Foram utilizados 60 discos de dentina com aproximadamente 6 mm de diâmetro e 1,5 mm de altura, obtidos de molares humanos hígidos. Os espécimes foram divididos em dois grupos de acordo com a prévia aplicação ou não do fosfato de cálcio (TeethMate Desensitizer - Kuraray Notitake Dental Inc.). Cada grupo foi dividido em três subgrupos conforme o tratamento realizado (n=10): A- Adesivo (Single Bond Universal - 3M-ESPE), AL- Adesivo + Laser (Nd: YAG 60 mJ) , LAL- Laser + Adesivo + Laser. A permeabilidade foi mensurada em três momentos: com smear layer presente (inicial), após a abertura dos túbulos (máxima) e depois do tratamento (final). O percentual da permeabilidade inicial e final foi calculada em relação a permeabilidade máxima. Após a fotopolimerização do adesivo foi aplicado uma camada de 3 mm com a resina composta Filtek Z350 XT (3M-ESPE) com técnica incremental. Os espécimes foram submetidos a 5000 ciclos térmicos e 120.000 ciclos mecânicos, e posteriormente foi utilizado o teste de microtração. Adicionalmente foram observados em microscopia eletrônica de varredura (MEV) e microscopia confocal de varredura a laser (MCVL). Os grupos foram analisados pelo teste da analise de variância (ANOVA), teste t pareado e teste Tukey, adotando o nível de significância de 5%. Não foram observadas diferenças significativas entre os grupos na permeabilidade inicial (p=0,48) e após o tratamento (p=0,70). O percentual de permeabilidade após o tratamento foram (A: 42,11; AL: 39,09; LAL: 35,78; FA: 40,38; FAL: 34,23; FLAL: 30,25). O teste t pareado mostrou que o tratamento LAL promoveu uma redução significativa da permeabilidade em relação à inicial, tendo o fosfato de cálcio sido (p=30,25) ou não aplicado (p=35,78). Os tratamentos tiveram diferenças significativas na resistência de união, foi observado que os grupos FAL(31,53MPa), FLAL(31,37MPa) e AL(29,72MPa) apresentaram as maiores médias, que diferiram estatisticamente dos grupos restaurados só com Adesivo. Os demais grupos não apresentaram diferenças significantes (A: 24,34MPa; FA: 26,40MPa; LAL: 29,68MPa). Podemos concluir que o laser Nd:YAG aplicado antes e depois do sistema adesivo (Com e sem Fosfato de Cálcio), influenciou na redução da permeabilidade dentinária e os diferentes tratamentos na dentina influenciam significativamente a resistência de união entre a dentina e a resina, os grupos FAL, FLAL e AL apresentaram os melhores resultados. A correlação entre os parâmetros não teve influencia. / The objective of this study was to evaluate in vitro effect the association of calcium phosphate, Nd:YAG laser and adhesive system on dentin permeability and bond strength. Sixty dentin discs, approximately 6 mm in diameter and 1,5 mm high, were obtained from healthy human molars. The specimens were divided into two groups according to the prior application of calcium phosphate (TeethMate Desensitizer - Kuraray Noritake Dental Inc.). Each group was divided into three subgroups according to the treatment performed: A-Adhesive (Single Bond Universal - 3M-ESPE), AL- Adhesive + Laser (Nd: YAG 60 mJ) and LAL- Laser + Adhesive + Laser. The dentin permeability was measured in three moments: with smear layer present (initial), after opened tubules (maximum) and after treatment (final). The percentage of the initial and final permeability was calculated in relation to the maximum permeability. After adhesive photopolymerization, was applied the composite resin Filtek Z350 XT (3M-ESPE) with incremental technique. The specimens were cycled to 5000 thermal cycles and 120,000 mechanical cycles, and microtensile bond strength test was applied. Additionally they were observed in scanning electron microscopy (SEM) and confocal laser scanning microscopy (CLSM). The groups were analyzed by ANOVA, paired t test and Tukey test (5%). No significant differences were observed between the groups on initial permeability (p=0.48) and after treatment (p=0.70). Permeability percentage after treatment was (A: 42.11, AL: 39.09, LAL: 35.78, FA: 40.38, FAL: 34.23, FLAL: 30.25). The paired t-test showed that LAL treatment promoted a significant reduction of the permeability in relation to the initial one, with calcium phosphate (p=30.25) or not applied (p=35.78). The treatments had significant differences in bond strength; FAL (31,53 MPa), FLAL (31,37 MPa) and AL (29,72 MPa) groups presented the highest averages, which differed statistically from the groups restored with only Adhesive. The other groups did not present statistically significant differences (A: 24.34 MPa, AF: 26.40 MPa, LAL: 29.68 MPa). It can be concluded that when the Nd:YAG laser was applied before and after the adhesive system (with and without Calcium Phosphate), it influenced the reduction of dentin permeability and the different treatments in dentin significantly influenced the bond strength between dentin and resin , the groups AL, LAL with application of Phosphate and AL without the use of Phosphate showed the best results. The correlation between the parameters had no influence.
798

Avaliação do Clinpro XT® na redução da permeabilidade da dentina radicular e resistência a desafios ácidos, na obliteração de túbulos dentinários e rugosidade superficial da dentina / Clinpro XT® evaluation in reducing the permeability of root dentin and resistance to acids challenges, the obliteration of dentinal tubules and surface roughness of dentin

Terenzi, Mayara [UNESP] 23 March 2016 (has links)
Submitted by MAYARA TERENZI null (mayara_terenzi@hotmail.com) on 2016-05-01T13:15:46Z No. of bitstreams: 3 Dissertação de Mestrado - Mayara Terenzi.pdf: 1718757 bytes, checksum: 20f87c0423de8d0417680da47944a37f (MD5) Anexo A.pdf: 90620 bytes, checksum: 7670a876bb4321d72791935fcb19bfe4 (MD5) Anexo B.tif: 7046482 bytes, checksum: ba852948774319d877a6088b781b43b7 (MD5) / Rejected by Felipe Augusto Arakaki (arakaki@reitoria.unesp.br), reason: Solicitamos que realize uma nova submissão seguindo as orientações abaixo: Foram submetidos 2 arquivos PDF’s e 1 arquivo TIF, a dissertação/tese deve estar em um único arquivo, inclusive os apêndices e anexos e deve estar no formato PDF. Lembramos que o arquivo PDF não deve estar protegido. Corrija estas informações e realize uma nova submissão contendo o arquivo correto. Agradecemos a compreensão. on 2016-05-04T13:37:28Z (GMT) / Submitted by MAYARA TERENZI null (mayara_terenzi@hotmail.com) on 2016-05-10T17:37:12Z No. of bitstreams: 1 Dissertação Mayara 100516.pdf: 8045470 bytes, checksum: 53ac4e21e2f77379964f4bc5b09e8f7a (MD5) / Approved for entry into archive by Juliano Benedito Ferreira (julianoferreira@reitoria.unesp.br) on 2016-05-12T19:23:37Z (GMT) No. of bitstreams: 1 terenzi_m_me_arafo.pdf: 8045470 bytes, checksum: 53ac4e21e2f77379964f4bc5b09e8f7a (MD5) / Made available in DSpace on 2016-05-12T19:23:37Z (GMT). No. of bitstreams: 1 terenzi_m_me_arafo.pdf: 8045470 bytes, checksum: 53ac4e21e2f77379964f4bc5b09e8f7a (MD5) Previous issue date: 2016-03-23 / O completo entendimento e tratamentos eficazes e definitivos para a hipersensibilidade dentinária, ainda não estão estabelecidos. O grande desafio está em encontrar uma substância que elimine efetivamente a sensação dolorosa não permitindo sua recidiva. O objetivo deste estudo in vitro foi determinar a eficácia do Clinpro XT® na redução da permeabilidade dentinária e avaliar a resistência deste produto a desafios ácidos. O grau de obliteração dos túbulos dentinários e a rugosidade superficial após aplicação do produto, também foram avaliados. Foram utilizados 65 terceiros molares humanos íntegros para a preparação de 65 amostras que foram ligadas a um sistema de pressão hidráulico para mensurar a permeabilidade dentinária após os seguintes passos: (1) preparação da amostra; (2) tratamento com ácido fosfórico a 37% durante 30 segundos; (3) aplicação do Clinpro XT®; (4) primeiro; (5) segundo e (6) terceiro desafios ácidos, respectivamente. As amostras foram divididas aleatoriamente em 5 grupos (n = 13) de acordo com as diferentes soluções ácidas: refrigerante a base de cola, suco natural de limão, vinagre de vinho, vinho branco e energético. 10 terceiros molares adicionais foram utilizados para a preparação de 20 amostras para análise do grau de obliteração dos túbulos dentinários, através da microscopia eletrônica de varredura, e, rugosidade superficial, através de um rugosímetro. Pode-se concluir que Clinpro XT® foi eficaz na redução da permeabilidade dentinária e esse efeito se manteve após três desafios com diferentes substâncias ácidas. Além disso, o produto testado foi capaz de promover a obliteração dos túbulos dentinários e a redução da rugosidade superficial. / The complete understanding and effective and definitive treatment for dentin hypersensitivity are not yet established. The challenge is to find a substance that effectively eliminates the painful sensation not allowing their recurrence. The purpose of this in vitro study was to determine the efficacy of Clinpro XT® in reducing dentin and evaluate the strength of the product acid challenges. The obliteration of the dentinal tubules, and surface roughness after application of the product, were also evaluated. 65 intact human third molars were used for the preparation of 65 samples were bound to a hydraulic pressure system to measure the dentin after the following steps: (1) sample preparation; (2) treatment with 37% phosphoric acid for 30 seconds; (3) application of Clinpro XT®; (4) first; (5) and second (6) third challenges acids, respectively. The samples were randomly divided into 5 groups (n = 13) according to the different acid solutions: refrigerant cola, natural lemon juice, wine vinegar, white wine and energy drink. 10 thirds additional molars were used to prepare 20 samples for analysis of the degree of obliteration of the dentinal tubules, by scanning electron microscopy, and surface roughness, using a roughness. It can be concluded that Clinpro XT® was effective in reducing dentinal permeability and this effect was maintained after three challenges with different acids. Furthermore, the test product is capable of promoting the obliteration of the dentinal tubules and reduce surface roughness.
799

Estudo quantitativo da permeabilidade de lesões cariosas naturais de esmalte à solução de Thoulet

Meira, Kássia Regina Simões 27 February 2014 (has links)
Made available in DSpace on 2015-05-14T12:56:04Z (GMT). No. of bitstreams: 1 arquivototal.pdf: 2036979 bytes, checksum: f336711f559785dc6ec4729336aa8edc (MD5) Previous issue date: 2014-02-27 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / In natural enamel caries, remineralization and resin infiltration are directly dependent on the permeability of the enamel to the agents that promote them. Due to its low permeability, the surface layer of carious lesions has been considered, a natural barrier for penetration of such agents. In this study we provide, for the first time, quantitative volumetric data on the infiltration of a test solution (aqueous solution of mercuric and potassium iodide: Thoulet s solutions) in the surface layer of natural enamel caries and confirmed our hypothesis that the ratio of the squared water volume by pore volume (αd) is, among all major component volumes (mineral, organic, total water and loosely bound water), the best predictor of the proportion of the pore volume infiltrated by the tested solutions. The predictive value of αd was higher for Thoulet s solution with refractive index 1.47 (R2 = 0.505) compared to Thoulet s solution with refractive index 1.40 (R2=0.435). Real-time 2D mapping of infiltration revealed that penetration of the solution started on the original enamel surface, followed the prism paths towards the bottom of the body of the lesion, and caused air flow in the opposite direction. Infiltration was negligible through the pores at the surfaces exposed by cutting and grinding. Data on effective pore volume, pore viscosity and from fluid flow mechanics provided new information on the nature of the infiltration of materials in the surface layer of natural enamel caries. Our results might provide a deeper insight into the transport of agents used to promote remineralization and resin infiltration in natural enamel caries. / Em lesões cariosas naturais de esmalte, os agentes terapêuticos que promovem a remineralização e infiltração do esmalte desmineralizado por resina dependem diretamente da permeabilidade do tecido. A camada superficial tem sido considerada uma barreira para penetração desses agentes devido à sua baixa permeabilidade. Neste estudo, pela primeira vez, são fornecidos dados volumétricos quantitativos sobre a infiltração de uma solução teste (solução aquosa de iodeto de mercúrio e de potássio - Solução de Thoulet) na camada superficial da lesão cariosa natural de esmalte. Confirmou-se a hipótese de que a razão do volume de água ao quadrado dividido pelo volume de poros (αd) é dentre todos os volumes (mineral, orgânico, água total e água fracamente aderida), o melhor preditor da proporção do volume de poros infiltrados pelas soluções testadas. O valor preditivo de αd foi maior pra Solução de Thoulet com índice de refração 1,47 (R2= 0,505) em comparação à Solução de Thoulet com índice de refração 1,40 (R2= 0,435). O mapeamento em 2D da infiltração em tempo real revelou que a penetração da solução começou inicialmente através da superfície do esmalte, seguindo para o interior do corpo da lesão seguindo a trajetória dos prismas e provocando um fluxo de ar no sentido oposto. A infiltração foi insignificante através dos poros nas superfícies expostas por desgaste. Dados sobre os volumes efetivos, viscosidade e da mecânica do fluxo de fluidos nos poros, forneceram informações nunca antes publicadas sobre a natureza da infiltração de materiais na camada superficial e lesão cariosa natural de esmalte. O presente estudo pode fornecer uma visão mais profunda sobre o transporte de agentes usados para a remineralização e infiltração de resinas na lesão cariosa natural de esmalte.
800

Estudo da permea??o em membranas quitosana

Sobreira, Raimundo Nonato Meneses 23 August 2008 (has links)
Made available in DSpace on 2014-12-17T14:06:50Z (GMT). No. of bitstreams: 1 RaimundoNMS.pdf: 436165 bytes, checksum: 1ef32081d941d323bf771b6bcb23e258 (MD5) Previous issue date: 2008-08-23 / This study proposes to do a study on the mathematical modeling of permeation of films based on chitosan. To conduct the study were obtained membranes with various compositions: a virtually pure membrane-based chitosan; one of chitosan associated with poly (ethylene oxide (PEO). The membranes of pure chitosan were treated with plasma in atmospheres of oxygen, argon and methane. The various types of films were characterized as to its permeation regarding sufamerazina sodium. In the process of mathematical modeling were compared the standard method of obtaining the coefficient of permeation recital straight down the slope of the plot obtained by extinction / time with a the integration process of numerical permeability rate will be calculated from the spectroscopy UV / O presente trabalho prop?e fazer um estudo sobre a modelagem matem?tica da permea??o de pel?culas ? base de quitosana. Para realizar o estudo foram obtidas membranas com duas composi??es: Uma membrana pura praticamente ? base de quitosana e uma de quitosana associada com poli(?xido de etileno(PEO) .No trabalho foram usados tamb?m resultados obitidos em ensaios de permea??o com membranas de quitosana pura tratadas com plasma em atmosferas de oxig?nio; arg?nio e metano Os diversos tipos de pel?culas foram caracterizados quanto ? sua permea??o em rela??o ? sufamerazina de s?dio. No processo de modelagem matem?tica foram comparado o m?todo padr?o de obten??o do coeficiente de permea??o considerando a inclina??o da reta regressiva obtida pela plotagem absorb?ncia/tempo com um processo de integra??o num?rica A taxa de permeabilidade ser? calculada a partir da espectroscopia do UV usando como substancia alvo a sulfamerazina de s?dio

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