• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 296
  • 93
  • 8
  • 8
  • 7
  • 7
  • 4
  • 3
  • 2
  • 2
  • 1
  • 1
  • 1
  • 1
  • 1
  • Tagged with
  • 464
  • 110
  • 107
  • 85
  • 73
  • 68
  • 64
  • 57
  • 52
  • 50
  • 50
  • 49
  • 47
  • 44
  • 39
  • 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.
41

Multiscale analyses of microbial populations in extreme environments

Martinez, Robert J. January 2008 (has links)
Thesis (Ph.D.)--Biology, Georgia Institute of Technology, 2008. / Committee Chair: Patricia Sobecky; Committee Member: Ellery Ingall; Committee Member: Jim Spain; Committee Member: Martial Taillefert; Committee Member: Thomas DiChristina.
42

Syntheses and downstream purification of 1,2,4-butanetriol

Lau, Man Kit. January 2007 (has links)
Thesis (PH. D.)--Michigan State University. Dept. of Chemistry, 2007. / Title from PDF t.p. (viewed on Sept. 8, 2009) Includes bibliographical references. Also issued in print.
43

Initial oxidation of n-decane by Candida intermedia

Liu, Chao-Min, January 1970 (has links)
Thesis (Ph. D.)--University of Wisconsin--Madison, 1970. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references.
44

Development of an in vitro assay for MMP cleavage /

Wu, Wing-kei, Ricky. January 2005 (has links)
Thesis (M. Med. Sc.)--University of Hong Kong, 2005.
45

Evaluation of storage conditions for assessing DNA damage using the comet assay /

Villavicencio, Dante. January 2006 (has links)
Thesis (M.S.)--Indiana University, 2007. / Title from screen (viewed on Apr. 27, 2007) Department of Pharmacology & Toxicology, Indiana University-Purdue University Indianapolis (IUPUI) Includes vita. Includes bibliographical references (leaves 71-84)
46

Bioaerossóis na indústria farmacêutica / Bioareorols in the pharmaceutical industry

Guilherme Neves Ferreira 27 April 2009 (has links)
Este estudo teve como finalidade, testar uma barreira contra a contaminação microbiológica em placas de contato, utilizadas em monitoramento de salas limpas para fabricação de produtos farmacêuticos estéreis. Durante o ano de 2007, foram realizados testes de contato com a utilização da mencionada barreira, e os resultados foram comparados com dados dos anos de, 2004, 2005 e 2006, quando a barreira não foi utilizada. Os ambientes utilizados para os testes foram duas salas limpas de uma planta farmacêutica localizada no Rio de Janeiro. Nos mencionados ambientes é necessário o uso de uma vestimenta especial, de forma a evitar que partículas do corpo dos operadores, bactérias e fungos, migrem para a superfície externa do uniforme e coloquem em risco a esterilidade dos produtos. Sendo assim, foi proposta a colocação de uma camiseta diretamente sobre a pele do operador durante todo o ano de 2007 de forma a evitar ou reduzir a possibilidade de migração dessas partículas; e os resultados foram comparados com os anos de 2004, 2005 e 2006, quando a camiseta não foi usada. Os testes demonstraram que houve uma redução de cerca de 50% na ocorrência de placas contaminadas. Com relação ao número total de colônias formadas, a redução foi de 75% na comparação com os anos de 2004 e 2005 e de 50% com relação ao ano de 2006 / This study had as objective to test a barrier against microbiological contamination in contact plates that are used in sterile pharmaceutical products clean rooms monitoring. During 2007 the tests were performed and compared with data from, 2004, 2005 and 2006, when the mentioned barrier was not used. The test environments were two clean rooms from a pharmaceutical plant located at Rio de Janeiro. In the mentioned environments the use of special garments is necessary for avoiding that particles from operators bodies, bacteria and most remain in contact with the room environment, adding risk to the sterilized products. So, it was proposed the use of undershirt between the garment and the operator skin for reducing the contact plates contamination during the regular rooms monitoring. This undershirt was used during 2007 and the results were compared with the samples of 2004, 2005 and 2006 when the undershirt was not used. The results demonstrated that it was obtained a reduction of about 50% in relation to contaminated plates. In relation to the total number of colonies the reduction was 75% in comparison with 2004 and 2005, and 50% in comparison with 2006
47

estudo in situ do efeito antimicrobiano da terapia fotodinÃmica em lesÃes de cÃrie dentinÃria / In situ study of the antimicrobial effect of photodynamic therapy in dentine caries lesions

Juliana Paiva Marques Lima 04 March 2009 (has links)
Terapia fotodinÃmica à um conceito de tratamento, sugerido pela literatura como uma potencial terapia capaz de proporcionar inativaÃÃo microbiana. Desta forma, este estudo avaliou a aÃÃo da terapia fotodinÃmica sobre lesÃes de cÃrie dentinÃria, mediante um delineamento in situ de Ãnica fase. Durante 14 dias, 20 voluntÃrios utilizaram dispositivos intra-orais palatinos, contendo, cada um, seis blocos de dentina humana. Todos os voluntÃrios foram instruÃdos a gotejar sobre os blocos uma soluÃÃo de sacarose a 40% dez vezes ao dia, simulando um desafio cariogÃnico e a utilizar dentifrÃcio fluoretado trÃs vezes ao dia. No final deste perÃodo clÃnico, os blocos foram randomicamente alocados em um dos seguintes grupos: sem fotossensibilizador e luz (F-L-); com fotossensibilizador e sem luz (F+L-); sem fotossensibilizador e com luz com densidade de energia de 47J/cm2(F-L+47); sem fotossensibilizador e com luz com densidade de energia de 94J/cm2 (F-L+94); com fotossensibilizador e irradiados com densidade de energia de 47J/cm2(F+L+47); com fotossensibilizador e irradiados com densidade de energia de 94J/cm2(F+L+94). O fotossensibilizador de escolha foi azul de orto-toluidina na concentraÃÃo de 100 &#61549;g/mL e a irradiaÃÃo originada de um diodo emissor de luz (LED) com comprimento de onda predominante em 638,8nm. Amostras de dentina cariada de cada bloco foram coletadas antes e apÃs os tratamentos e analisadas para contagem de microorganismos totais, estreptococos totais, estreptococos grupo mutans e lactobacilos. Os dados das contagens foram transformados em log10, os valores de log reduÃÃo foram obtidos e as diferenÃas estatÃsticas identificadas atravÃs dos testes ANOVA One way e Tukey Kramer (p<0,05). Em ambas as anÃlises, foram observadas diferenÃas estatisticamente significativas entre as contagens microbiolÃgicas antes e depois dos tratamentos nos grupos (F-L+94), (F+L+47), (F+L+94) para todos os microrganismos testados. Concluiu-se que a terapia fotodinÃmica foi efetiva na morte microbiana nos parÃmetros testados e que o tempo de exposiÃÃo da dentina à luz de 10 minutos, tambÃm, promoveu inativaÃÃo microbiana. / Photodynamic therapy is a concept of treatment, suggested by the literature as a potential therapy capable of inactivating microbial. Thus, this study assessed the efficacy of photodynamic therapy on injuries of dentine caries by a in situ design of single phase. During 14 days, 20 volunteers wore intra-oral palatal devices containing six human dental dentine slabs. The volunteers wore asked to drop a 40% sucrose solution onto the slabs ten times per day, in order to simulate a cariogenic challenge and to use fluoride dentifrice three times per day. At the end of the experimental period the slabs were randomly allocated into one of the following groups: without sensitizer and light (S-L-); with sensitizer and without light (S+L-); without sensitizer and irradiated with 47J/cm2 energy density (S-L+47); without sensitizer and irradiated with 94J/cm2 energy density (S-L+94); with sensitizer and irradiated with 47J/cm2 energy density (S+L+47); and with sensitizer and irradiated with 94J/cm2 energy density (S+L+94). The sensitizer of choice was the toluidine blue O at 100 &#61549;g/mL concentration and radiation originated from a light-emitting diode (LED) with a 638,8 nm predominant wavelength. Before and after the treatments, dentine samples were collected and analyzed to figure out the total microorganisms, total streptococci, mutans streptococci and lactobacilli. The data of the counts were transformed into log10.The values of log reduction was achieved and the statistical differences identified by ANOVA One way and Tukey Kramer tests (p<0,05). In both analyses statistically significant difference between the microbial counts before and after treatment in groups (S-L+47), (S+L+94), (S+L+94) for all microorganisms tested are founded. It was concluded that PACT in the tested parameters was effective in promoting microbial death and that the exposure time of dentine to 10 minutes of light was also effective in microbial inactivation.
48

An Assay Method for Determining Extra-Cellular Lipases from Pseudomonas aeruginosa

Christensen, John N. 05 1900 (has links)
The applicability of an isotopically labelled assay system to determine the lipase production in Pseudomonas aeruginosa was evaluated. Supernatant from cultures of Pseudomonas aeruginosa grown in a medium containing olive oil was incubated with a substrate containing labelled trioleate. Fatty acids were isolated by means of a liquid-liquid partition system. Enzyme activity was determined by measuring the amounts of free fatty acid by liquid scintillation counting. Findings indicate that the isotopicallylabelled, liquid-liquid partitioning assay is reliable, sensitive and adaptable to rapid assay conditions. It was also determined that different strains of Pseudomonas aeruginosa produce varying amounts of lipase. Partial purification of supernatant by gel filtration produced two protein peaks showing enzymatic activity.
49

Studies of the Membrane and DNA Gyrase Inhibiting Antibiotics on Pigment Synthesis in Corynebacterium Poinsettiae

Tabarya, Daniel 08 1900 (has links)
The purpose of this study was (1) to determine whether a correlation exists among the protein profiles, extracted from cell membranes of mutants belonging to five pigment cluster groups, (2) to locate the protein moiety and cartenoprotein complex in the membranes of wild type and colorless mutant (designated W-19) of C. poinsettae and to show whether there are any structural differences between cell membranes of the wild type and a colorless mutant, (3) to determine the effect of six antibiotics on cartenoid gene expression.
50

Development of antibody and antigen detection assays and vaccines for SARS associated coronavirus

Wong, Hiu-ling, Beatrice., 黃曉靈. January 2007 (has links)
published_or_final_version / abstract / Microbiology / Doctoral / Doctor of Philosophy

Page generated in 0.0774 seconds