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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

Paediatric sedation and general anaesthetic services : choices for the future

Carson, Pauline January 1998 (has links)
No description available.
2

Extrakce zubů u nemocných s poruchou hemokoagulace / Tooth extractions in patients with coagulation disorder

Houba, Robert January 2006 (has links)
The study deals with the question of minor oral surgery procedures, dental extractions especially, in patients suffering from haemocoagulation disorder. The aim of this study was 1) the clinical attestation of the risk of bleeding that may follow the dental extraction in patients with non-interrupted oral administration of drugs with the anticoagulant and antiplatelet effects and 2) suggestion of the schedules of surgical procedures suitable for this kind of patients and for the realization in the standard dental office. The opening theoretical part analyses the principle of haemocoagulation, the surway of individual inherited and acquired bleeding disorders and the main principles of treatment of bleeding patients in dental offices with the emphasis on the local security of the surgical wound. In the proper study we present the observation and evaluation of bleeding complications after the standard dental extractions in 3 groups of persons (age range, 19 to 93 years). In all patients, one or more extractions were performed. 99 patients were treated with oral anticoagulant therapy without any interruption and underwent 199 extractions. 149 patients, treated with antiplatelet therapy (acetylsalicylic acid) without interruption, underwent 347 extractions. 160 healthy subjects with 316 extractions served as a...
3

Extrakce zubů u nemocných s poruchou hemokoagulace / Tooth extractions in patients with coagulation disorder

Houba, Robert January 2006 (has links)
The study deals with the question of minor oral surgery procedures, dental extractions especially, in patients suffering from haemocoagulation disorder. The aim of this study was 1) the clinical attestation of the risk of bleeding that may follow the dental extraction in patients with non-interrupted oral administration of drugs with the anticoagulant and antiplatelet effects and 2) suggestion of the schedules of surgical procedures suitable for this kind of patients and for the realization in the standard dental office. The opening theoretical part analyses the principle of haemocoagulation, the surway of individual inherited and acquired bleeding disorders and the main principles of treatment of bleeding patients in dental offices with the emphasis on the local security of the surgical wound. In the proper study we present the observation and evaluation of bleeding complications after the standard dental extractions in 3 groups of persons (age range, 19 to 93 years). In all patients, one or more extractions were performed. 99 patients were treated with oral anticoagulant therapy without any interruption and underwent 199 extractions. 149 patients, treated with antiplatelet therapy (acetylsalicylic acid) without interruption, underwent 347 extractions. 160 healthy subjects with 316 extractions served as a...
4

Thematic knowledge extraction

Zhang, Shaomin January 2003 (has links)
No description available.
5

Frequência dos diferentes protocolos de extrações nos tratamentos ortodônticos conduzidos na Faculdade de Odontologia de Bauru FOB-USP, nos últimos 35 anos / Frequency evaluation of different extraction protocols in orthodontic treatments conducted at Bauru Dental School, University of São Paulo, in the last 35 years

Maria, Fábio Rogério Tôrres 03 August 2010 (has links)
O presente estudo objetivou realizar um levantamento retrospectivo de todos os planejamentos ortodônticos realizados pelo Departamento de Ortodontia (FOB USP) desde 1973, para que pudessem ser avaliados os protocolos de tratamento escolhidos à época, principalmente quanto à decisão de extrações e suas freqüências. A amostra constitui-se inicialmente de 3745 documentações ortodônticas arquivadas pelo Departamento de Ortodontia, das quais 332 documentações foram descartadas seguindo alguns fatores de exclusão, tais como casos transferidos, desistências e informações e exames incompletos. A amostra total de 3413 pacientes foi avaliada de acordo com o protocolo de tratamento escolhido, classificados como: Protocolo 0 (Sem extrações); Protocolo 1 (Extrações de 4 primeiros pré-molares); Protocolo 2 (2 primeiros pré-molares superiores e 2 segundos inferiores); Protocolo 3 (2 pré-molares superiores); Protocolo 4 (4 segundos pré-molares); Protocolo 6 (Incisivos e caninos); Protocolo 7 (Primeiros e segundos molares); Protocolo 8 (extrações atípicas); Protocolo 9 (grupo de agenesias e perdas precoces). Estes protocolos aferidos, foram então divididos em 7 grupos, definidos como 7 intervalos cronológicos a cada 5 anos: Intervalo 1 (1973-1977); Intervalo 2 (1978-1982); Intervalo 3 (1983-1987); Intervalo 4 (1988-1992); Intervalo 5 (1993-1997); Intervalo 6 (1998-2002); Intervalo 7 (2003-2007). Estes intervalos foram então comparados entre si para que as freqüências dos protocolos pudessem definir possíveis tendências predominantes a cada época testada. Os resultados demonstraram diferenças estatisticamente significantes para 7 dos 10 protocolos avaliados entre os intervalos considerados, evidenciando uma grande diferença de freqüência dos principais protocolos de tratamento ao longo destes 35 anos avaliados. Portanto conclui-se que a escolha pelos protocolos de tratamento sofreram influências de filosofias e dogmas vigentes durante os intervalos avaliados. / The purpose of this retrospective study was to evaluate all orthodontic treatment plannings conducted at the Orthodontic Department at Bauru Dental School, University of São Paulo, since 1973, in order to investigate extraction and nonextraction frequency protocols selected at each considered period. The sample comprised initially 3745 records of treated patients, that according to exclusion criteria, reduced the final sample to 3413 documentations. This total sample was evaluated according to the protocol choice, being divided into 10 groups: Protocol 0 (nonextraction group); Protocol 1 (4-first premolar extractions); Protocol 2 (2-maxillary first and 2-mandibular second premolar extractions); Protocol 3 (2-maxillary premolar extractions); Protocol 4 (4-second premolar extractions); Protocol 5 (asymmetric premolar extractions); Protocol 6 (incisor and canine extractions); Protocol 7 (first and second molar extractions); Protocol 8 (atypical extractions) and Protocol 9 (agenesis and previously missing teeth group). These 3413 obtained protocols were divided into seven 5-year intervals: Interval 1 (1973-1977); Interval 2 (1978-1982); Interval 3 (1983-1987); Interval 4 (1988-1992); Interval 5 (1993-1997); Interval 6 (1998-2002); Interval 7 (2003-2007). The frequency of each protocol was compared among the 7 intervals, using the Proportion Test, in order to identify some predominant trends at each tested period. The results showed that 7 frequency protocols were significantly different among the 7 considered intervals, evidencing that the protocols choice was influenced by some dominant philosophies or dogmas during the evaluated periods.
6

Frequência dos diferentes protocolos de extrações nos tratamentos ortodônticos conduzidos na Faculdade de Odontologia de Bauru FOB-USP, nos últimos 35 anos / Frequency evaluation of different extraction protocols in orthodontic treatments conducted at Bauru Dental School, University of São Paulo, in the last 35 years

Fábio Rogério Tôrres Maria 03 August 2010 (has links)
O presente estudo objetivou realizar um levantamento retrospectivo de todos os planejamentos ortodônticos realizados pelo Departamento de Ortodontia (FOB USP) desde 1973, para que pudessem ser avaliados os protocolos de tratamento escolhidos à época, principalmente quanto à decisão de extrações e suas freqüências. A amostra constitui-se inicialmente de 3745 documentações ortodônticas arquivadas pelo Departamento de Ortodontia, das quais 332 documentações foram descartadas seguindo alguns fatores de exclusão, tais como casos transferidos, desistências e informações e exames incompletos. A amostra total de 3413 pacientes foi avaliada de acordo com o protocolo de tratamento escolhido, classificados como: Protocolo 0 (Sem extrações); Protocolo 1 (Extrações de 4 primeiros pré-molares); Protocolo 2 (2 primeiros pré-molares superiores e 2 segundos inferiores); Protocolo 3 (2 pré-molares superiores); Protocolo 4 (4 segundos pré-molares); Protocolo 6 (Incisivos e caninos); Protocolo 7 (Primeiros e segundos molares); Protocolo 8 (extrações atípicas); Protocolo 9 (grupo de agenesias e perdas precoces). Estes protocolos aferidos, foram então divididos em 7 grupos, definidos como 7 intervalos cronológicos a cada 5 anos: Intervalo 1 (1973-1977); Intervalo 2 (1978-1982); Intervalo 3 (1983-1987); Intervalo 4 (1988-1992); Intervalo 5 (1993-1997); Intervalo 6 (1998-2002); Intervalo 7 (2003-2007). Estes intervalos foram então comparados entre si para que as freqüências dos protocolos pudessem definir possíveis tendências predominantes a cada época testada. Os resultados demonstraram diferenças estatisticamente significantes para 7 dos 10 protocolos avaliados entre os intervalos considerados, evidenciando uma grande diferença de freqüência dos principais protocolos de tratamento ao longo destes 35 anos avaliados. Portanto conclui-se que a escolha pelos protocolos de tratamento sofreram influências de filosofias e dogmas vigentes durante os intervalos avaliados. / The purpose of this retrospective study was to evaluate all orthodontic treatment plannings conducted at the Orthodontic Department at Bauru Dental School, University of São Paulo, since 1973, in order to investigate extraction and nonextraction frequency protocols selected at each considered period. The sample comprised initially 3745 records of treated patients, that according to exclusion criteria, reduced the final sample to 3413 documentations. This total sample was evaluated according to the protocol choice, being divided into 10 groups: Protocol 0 (nonextraction group); Protocol 1 (4-first premolar extractions); Protocol 2 (2-maxillary first and 2-mandibular second premolar extractions); Protocol 3 (2-maxillary premolar extractions); Protocol 4 (4-second premolar extractions); Protocol 5 (asymmetric premolar extractions); Protocol 6 (incisor and canine extractions); Protocol 7 (first and second molar extractions); Protocol 8 (atypical extractions) and Protocol 9 (agenesis and previously missing teeth group). These 3413 obtained protocols were divided into seven 5-year intervals: Interval 1 (1973-1977); Interval 2 (1978-1982); Interval 3 (1983-1987); Interval 4 (1988-1992); Interval 5 (1993-1997); Interval 6 (1998-2002); Interval 7 (2003-2007). The frequency of each protocol was compared among the 7 intervals, using the Proportion Test, in order to identify some predominant trends at each tested period. The results showed that 7 frequency protocols were significantly different among the 7 considered intervals, evidencing that the protocols choice was influenced by some dominant philosophies or dogmas during the evaluated periods.
7

Origine et processus de libération du sélénium dans l'aquifère carbonaté du site expérimental hydrogéologique de Poitiers / Origin and release process of selenium in the carbonate aquifer of the hydrogeological experimental site of Poitiers

Bassil, Joseph 18 December 2014 (has links)
La problématique environnementale du sélénium est principalement liée à son domaine de concentration très étroit entre toxicité et carence, et à sa présence diffuse au-delà des limites de potabilité dans de nombreux aquifères. Ainsi, des teneurs en sélénium supérieures à la norme européenne (10 ppb) ont été détectées dans les eaux souterraines du Site Expérimental Hydrogéologique (SEH) de Poitiers, dont le comportement hydrodynamique est particulièrement bien caractérisé. Le couplage d'études géochimiques, minéralogiques et pétrographiques a mis en évidence que les matériaux de remplissage (« argiles noires ») des structures karstiques subhorizontales présentes dans l'aquifère du Dogger au niveau du SEH, riches en sélénium et considérés comme la source potentielle du sélénium dissous dans ce réservoir, étaient issus de dépôts continentaux ayant subi des phases réductrices. Des fractionnements granulométriques et chimiques d'échantillons d'« argiles noires » ont montré que la fraction séléniée était principalement sous forme de sélénites dans la matrice et "associée" à la fraction organique soluble en milieu alcalin de nature majoritairement aliphatique. Des tests de lixiviation ont mis en évidence l'impact très important des conditions acido-basiques sur la quantité de sélénium dissous et sur la nature des espèces séléniées libérées dans les eaux. Les cinétiques de libération du sélénium tendent à montrer l'existence de trois processus principaux et les suivis de dissolution d'espèces majoritaires suggèrent que les mécanismes de libération du sélénium mis en jeu dans le contexte de l'étude sont principalement régis par des processus d'échange ou de complexation de surface. / The environmental issue of selenium is mainly related to the narrow range between its deficiency and toxicity concentrations, and to its widespread presence beyond the limits of potability in many aquifers. Selenium concentrations above the European standard (10 ppb) were detected in the groundwater of the Hydrogeological Experimental Site (HES) of Poitiers, whose hydrodynamic behavior is particularly well characterized.The coupling of geochemical, mineralogical and petrographic investigations showed that black argillaceous sediments that fulfill subhorizontal karstic cavities present in the Dogger aquifer at the SEH and considered as the potential source of dissolved selenium in the groundwater, are continental deposits that have been transformed in reduced environments.Grain-sized and chemical fractionations of these "black clays" showed that selenium is mainly present as selenite in the geological matrix and is "associated" with the alkali soluble organic fraction which is predominantly aliphatic.Leaching tests have highlighted the important impact of acid-base conditions on the amount of dissolved selenium and on the nature of selenium species released into the water. The release kinetics of selenium tends to show the existence of three main processes. The major species dissolutions suggest that the selenium release mechanisms are mainly governed by exchange process or surface complexation.
8

Synthesis of a fluorous benzodithiol support and its utility in the construction of diverse ring systems

Sharma, Maya 10 September 2008 (has links)
A method for the synthesis of a symmetrical fluorous tagged benzodithiol support has been developed through a seven-step synthetic pathway. The Wittig olefination and catalytic hydrogenation reactions were employed to attach two perfluoroalkyl chains in the o-positions of phthalaldehyde. These fluorous tags were used as soluble supports which facilitated the purification of the crude reaction mixtures using fluorous solid phase extraction (FSPE). A selective and high yielding dibromination reaction was developed to synthesize a fluorous tagged 1,2-dibromo aryl compound. A thorough study was carried out to demonstrate the ease of an aryl-sulfur bond formation with the 1,2-dibromo compound varying palladium catalysts and ligands. A new palladium catalyzed dithiolation reaction is reported to synthesize a surrogated dithiol, which was exploited as a precursor for the synthesis of hitherto inaccessible symmetrical fluorous tagged benzodithiol support. The utility of the benzodithiol was explored by the synthesis of benzodithianes with two aldehydes. The lithiated dithiane generated was further used to form a C-C bond employing the umpolung reaction. The ring-closing metathesis reaction using Grubbs II catalyst was performed to construct 5-membered and 6-membered spiro-ring systems. Several approaches were made to form a C-C bond with lithiated dithianes using various nitrogen containing electrophiles leading to N-heterocycles. / October 2008
9

Mineralogical and Microbial Controls on Iron Reduction in a Contaminated Aquifer-Wetland System

Howson, Andrea Melissa 2010 December 1900 (has links)
Iron reduction is an important redox reaction in anaerobic environments for both biological and chemical cycling of elements such as carbon. However, the controls on the rate and extent of iron reduction are poorly understood and unlike other major terminal electron accepting processes, iron reduction has the added complexity that its oxidized form (ferric iron) exists primarily as one of several solid phases in environments with pH greater than 3. Thus, the distribution and form of ferric iron minerals are important controls on iron reduction in natural systems. For the first phase of this research a series of sequential chemical extractions was performed on a core taken from a landfill-leachate-contaminated wetland-aquifer system at the Norman Landfill, Norman, OK. The phases targeted by the sequential extractions consist of easily water soluble salts and ions present in the soil solution; weakly acid soluble iron (such as siderite and ankerite); easily reducible iron (such as ferrihydrite and lepidocrocite); moderately reducible iron (such as goethite, akageneite, and hematite); organically bound iron; magnetite; and pyrite. The second phase of this research involved creating in situ microcosm experiments that exposed native microbial communities to a test solution amended with 2-line ferrihydrite (Fe5HO8∙4H2O), electron donor (lactate and acetate), and a conservative tracer for a period of eleven days. The kinetics of iron reduction were then evaluated over time and the resulting changes in microbial community structure documented through DNA and RNA analysis. Results document the spatial distribution of iron phases at the contaminated wetland-aquifer interface. Results of the sequential extractions indicate that ferrihydrite was present throughout the core. Accordingly, ferrihydrite was used in subsequent experiments on in situ microcosms to evaluate the kinetic controls on the microbial reduction of ferrihydrite. The results of these experiments show that microbial communities actively responded to the introduction of the amended ferrihydrite solution by increasing their community size and reducing ferrihydrite to an iron (II) phase in increasing amounts over an eleven day period.
10

Synthesis of a fluorous benzodithiol support and its utility in the construction of diverse ring systems

Sharma, Maya 10 September 2008 (has links)
A method for the synthesis of a symmetrical fluorous tagged benzodithiol support has been developed through a seven-step synthetic pathway. The Wittig olefination and catalytic hydrogenation reactions were employed to attach two perfluoroalkyl chains in the o-positions of phthalaldehyde. These fluorous tags were used as soluble supports which facilitated the purification of the crude reaction mixtures using fluorous solid phase extraction (FSPE). A selective and high yielding dibromination reaction was developed to synthesize a fluorous tagged 1,2-dibromo aryl compound. A thorough study was carried out to demonstrate the ease of an aryl-sulfur bond formation with the 1,2-dibromo compound varying palladium catalysts and ligands. A new palladium catalyzed dithiolation reaction is reported to synthesize a surrogated dithiol, which was exploited as a precursor for the synthesis of hitherto inaccessible symmetrical fluorous tagged benzodithiol support. The utility of the benzodithiol was explored by the synthesis of benzodithianes with two aldehydes. The lithiated dithiane generated was further used to form a C-C bond employing the umpolung reaction. The ring-closing metathesis reaction using Grubbs II catalyst was performed to construct 5-membered and 6-membered spiro-ring systems. Several approaches were made to form a C-C bond with lithiated dithianes using various nitrogen containing electrophiles leading to N-heterocycles.

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