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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.
131

Antecedents of work engagement in a financial institution / René Ferreira

Ferreira, René January 2009 (has links)
The industrialised world of today is characterised by transformation and concepts such as downsising, rightsising and restructuring have become a reality. South Africa is not excluded from this worldwide phenomenon. Economic and political changes as well as the shrinking labour market are also aggravating circumstances, which lead to increased job insecurity. This phenomenon might have a negative impact on employees' work engagement Due to all these changes, most organisations have to survive in a competitive global economy. Their survival depends on their ability to satisfy customer needs, while achieving quality, flexibility, innovation and organisational responsibility by the engagement and commitment of employees. The objective of this study was to investigate the relationships between antecedents (work role fit, co-worker relations, supervisor relations, co-worker norms, self-consciousness, resources and growth), psychological conditions (i.e. psychological meaningfuhaess, psychological availability, and psychological safety) and work engagement in a financial institution. A cross-sectional survey design was utilised. Employees (N= 132) in a financial institution, more specifically the branch-banking unit of FirstRand Group in the Free State Province, were included in the study. The Work Experience Scale and the Work Engagement Scale were administered together with a biographical questionnaire. Descriptive and inferential statistics were used to analyse the data. The results showed that psychological meaningfuhaess and psychological availability were significant predictors of work engagement. Cognitive, emotional and physical resources had the strongest effect on work engagement. Multiple regression analyses showed that psychological meaningfuhaess partially mediated the relationship between work role fit, co-worker relations, growth and work engagement. A total of 5% of the variance in psychological meaningfulness and a total of 2% of the variance in psychological availability were predicted by work role fit. Psychological availability partially mediated the relationship between resources, self-consciousness and work engagement. Recommendations for future research were made. / Thesis (M.A. (Industrial Psychology))--North-West University, Potchefstroom Campus, 2009.
132

Genetic and environmental factors influencing the behaviour and health of laying hens with emphasis on feather pecking

Ramadan, Sameh Gad Abdel-Hak 11 December 2007 (has links) (PDF)
The aim of this work was to investigate the effects of feather availability and imprinting to loose feathers in the litter on the incidence of feather pecking behaviour (FP), condition of the integument and fear reactions in two genotypes of laying hens. Hens that were deprived from loose feathers in the litter (feathers were collected 4 times/week) exhibited a significantly less rate of feather pecking, less number of severe FP and showed a better feather score in the laying period compared to the control groups (no feather treatment) in both Lohmann Tradition (LT) & Lohmann Silver (LS) genotypes. Addition of brown feathers to the floor in LT hens (feathers were added once/week) was associated with a reduction in feather pecking rate, the severe form of this behaviour and improved plumage and skin conditions. Contrary, the addition of white feathers to the floor in LS was associated with the highest rate of feather pecking, the highest severe form of this behaviour as well as the worst feather and skin conditions in the laying period compared to other groups of the same genotype. The LT birds in all feather treatments had a better feather cover than the LS birds. Hens that were imprinted to loose feathers in the litter in the rearing period exhibited a higher rate of FP, higher number of severe FP and showed the worst feather and skin conditions when feathers were collected from the floor during the laying period. Also, these hens reacted more fearful during the tonic immobility test. It is concluded that loose feathers may play a role in the development of feather pecking behaviour in laying hens. Large differences between genotypes were found in respect to the availability of loose feathers, feather pecking and plumage and integument condition. Imprinting of chicks to loose feathers from the floor may affect the incidence of feather pecking later on. Ziel dieser Arbeit war es, die Einflüsse des Federangebotes und der Prägung auf lose Federn in der Einstreu auf die Häufigkeit des Auftretens von Federpicken (FP), den Zustand des Integuments und die Furchtreaktionen an zwei Legehennengenotypen zu untersuchen. Hühnern beider untersuchter Genotypen (Lohmann Tradition (LT) und Lohmann Silber (LS)), denen die losen Federn 4 mal/ Woche aus der Einstreu abgesammelt wurden, zeigten eine geringere Federpickrate, eine geringere Anzahl der schweren Form des FP und eine bessere Gefiederbeschaffenheit in der Legeperiode verglichen mit der Kontrollgruppe (keine Federbehandlung). Das Hinzufügen brauner Federn zur Einstreu bewirkte bei LT Hennen eine Reduktion der FP-Rate, der schweren Form des Federpickens und verbesserte die Gefieder- und Hautbeschaffenheit. Dagegen führte das Hinzufügen weißer Federn in die Einstreu während der Legeperiode bei LS Hennen zur höchsten Federpickrate und Anzahl der schweren Form des Federpickens sowie zur schlechtesten Gefieder- und Hautbeschaffenheit im Vergleich zu anderen Gruppen des gleichen Genotyps. Hühner der LT Linie wiesen in allen Federbehandlungen eine bessere Befiederung als die LS Hühner auf. Hennen, die während der Aufzuchtsperiode auf lose Federn in der Einstreu geprägt wurden, zeigten nach Absammeln der Federn während der Legeperiode eine erhöhte FP-Rate mit einer erhöhten Anzahl der schweren Form des FP und die schlechteste Gefieder- und Hautbeschaffenheit. Außerdem reagierten diese Hühner ängstlicher während des Tests auf tonische Immobilität. Es kann geschlussfolgert werden, dass lose Federn in der Einstreu eine Rolle bei der Entwicklung des Federpickverhaltens von Legehennen spielen und dass Federpicken als Futtersuchverhalten interpretiert werden kann. Grosse Unterschiede zwischen den Genotypen bestanden hinsichtlich der Verfügbarkeit von losen Federn in der Einstreu, des Federpickens sowie der Gefieder- und Integumentbeschaffenheit. Eine Prägung der Junghennen auf lose Federn in der Einstreu könnte das Auftreten von Federpicken zu einem späteren Zeitpunkt beeinflussen.
133

Iron in human milk a study on the role of lactoferrin and the distribution of iron and some other trace elements in milk /

Fransson, Gun-Britt. January 1983 (has links)
Thesis (doctoral)--Uppsala University, 1983. / Includes bibliographical references (p. 29-36).
134

DETERMINING FOOD RESOURCES FOR AMERICAN BLACK DUCKS WINTERING AND SPRING STAGING ON THE EASTERN SHORE OF VIRGINIA

Lewis, Ben Lewis 01 August 2016 (has links)
AN ABSTRACT OF THE THESIS OF Benjamin S. Lewis Jr., for the Master of Science degree in ZOOLOGY, presented on December, 2, 2015 at Southern Illinois University Carbondale. TITLE: DETERMINING FOOD RESOURCES FOR AMERICAN BLACK DUCKS WINTERING AND SPRING STAGING ON THE EASTERN SHORE OF VIRGINIA MAJOR PROFESSOR: Dr. Michael W. Eichholz I evaluated food availability and food preference for American black ducks (Anas rubripes) wintering and spring staging on the Eastern Shore of Virginia during 2006–2007 and 2007–2008. I estimated food availability by taking core and sweep net sample at 78 sites selected by a stratified random sample throughout our study area, representing 4 dominant wetland habitat types. Seed and invertebrate biomass found in each of these samples were converted to measurements of kilograms per hectare. I found that salt marsh and mudflat habitats contained the highest amount of invertebrate biomass, while freshwater habitats contained the highest amount of seed biomass. I estimated food preference by collecting crop samples from 76 foraging black ducks. Animal matter made up 73% of the aggregate percent biomass of all foods eaten by black ducks. Foods found in black duck crops were compared to their availability in the environment and classified as either selected for, avoided or consumed relative to their availability. Although they were not found to be the most abundant foods, amphipods (Gammarus spp), salt marsh snails (Melampus bidentatus) and ribbed mussels (Geukensia demissa) were foods selected for in black duck wintering habitats. These food items are found most predominantly in salt marsh and mudflat habitats. As may be expected these areas are identified as the most important habitats for black ducks wintering on the Eastern Shore of Virginia. Results from this study provide energetic supply data for bioenergetically based habitat conservation for black ducks in Virginia and in the Atlantic Flyway. I found that the density of food items available for wintering black ducks were lower than densities found in in the more northern wintering range of the black duck and considerably lower than estimates from the wintering regions of other species of dabbling ducks. By concurrently measuring food selection and availability I was also able to reliably determine food preference. Removing avoided food items from food availability estimates provides more accurate estimates of preferred food biomass and it is important for bioenergetically based habitat models to use estimates of preferred food biomass in determining habitat objectives. I found that when avoided food items are removed, estimates of available food biomass decrease substantially, (up to 97%) further emphasizing discrepancies in estimates of food availability between coastal black duck wintering areas and estimates from the wintering regions of other species of dabbling ducks.
135

Uncertainty analysis in product service system : Bayesian network modelling for availability contract

Narayana, Swetha January 2016 (has links)
There is an emerging trend of manufacturing companies offering combined products and services to customers as integrated solutions. Availability contracts are an apt instance of such offerings, where product use is guaranteed to customer and is enforced by incentive-penalty schemes. Uncertainties in such an industry setting, where all stakeholders are striving to achieve their respective performance goals and at the same time collaborating intensively, is increased. Understanding through-life uncertainties and their impact on cost is critical to ensure sustainability and profitability of the industries offering such solutions. In an effort to address this challenge, the aim of this research study is to provide an approach for the analysis of uncertainties in Product Service System (PSS) delivered in business-to-business application by specifying a procedure to identify, characterise and model uncertainties with an emphasis to provide decision support and prioritisation of key uncertainties affecting the performance outcomes. The thesis presents a literature review in research areas which are at the interface of topics such as uncertainty, PSS and availability contracts. From this seven requirements that are vital to enhance the understanding and quantification of uncertainties in Product Service System are drawn. These requirements are synthesised into a conceptual uncertainty framework. The framework prescribes four elements, which include identifying a set of uncertainties, discerning the relationships between uncertainties, tools and techniques to treat uncertainties and finally, results that could ease uncertainty management and analysis efforts. The conceptual uncertainty framework was applied to an industry case study in availability contracts, where each of the four elements was realised. This application phase of the research included the identification of uncertainties in PSS, development of a multi-layer uncertainty classification, deriving the structure of Bayesian Network and finally, evaluation and validation of the Bayesian Network. The findings suggest that understanding uncertainties from a system perspective is essential to capture the network aspect of PSS. This network comprises of several stakeholders, where there is increased flux of information and material flows and this could be effectively represented using Bayesian Networks.
136

Avaliação de fontes de selênio e seus efeitos no perfil metabólico e condição reprodutiva de cães

Putarov, Thaila Cristina [UNESP] 17 June 2010 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:27:30Z (GMT). No. of bitstreams: 0 Previous issue date: 2010-06-17Bitstream added on 2014-06-13T19:56:23Z : No. of bitstreams: 1 putarov_tc_me_botfmvz.pdf: 721403 bytes, checksum: db6f049facb392575d608e413f06d369 (MD5) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / Universidade Estadual Paulista (UNESP) / O objetivo do trabalho foi comparar a biodisponibilidade e os efeitos antioxidantes de fontes de selênio na forma orgânica e inorgânica em dietas para cães. Foram utilizados 24 cães machos da raça Beagle distribuídos em três tratamentos: controle (TC-0,11 ppm de Se), inorgânico (TI-0,30 ppm de Se na forma de selenito de sódio) e orgânico (TO-0,30 ppm de Se na forma de seleno levedura). O experimento seguiu um delineamento em blocos casualizados com medidas repetidas no tempo, os animais foram blocados por idade. Os animais foram mantidos por 10 dias em gaiolas metabólicas e submetidos à coleta total de fezes e urina, e mais 70 dias em baias para demais análises. Nas amostras de ração, fezes, urina e pêlos foram feitas análises de selênio. No sangue total foi determinada a atividade da GSH-Px e no 11º dia do experimento foi realizada a curva pós-prandial de absorção de selênio, até doze horas após a ingestão das dietas. O status oxidativo e a capacidade antioxidante foram avaliados no soro sanguíneo através da metodologia de TBARS (substâncias reativas ao ácido tiobarbitúrico) e a capacidade antioxidante total (TAC), respectivamente. Os dados foram submetidos à análise de variância e as médias comparadas pelo teste de Tukey (P≤0,05). Para as varáveis ingestão de Se, excreção de Se nas fezes e retenção de Se o os animais do TC apresentaram menores valores quando comparados aos animais do TI e TO (P≤0,05). Não houve diferença para a excreção urinária e biodisponibilidade. Houve efeito de período para a concentração de selênio no plasma sanguíneo ocorrendo aumento para todos os animais. As concentrações de Se no pêlo dos animais dos grupos TI e TO foram maiores que as do TC ao final do experimento (P≤0,05). A área abaixo da curva do Se plasmático dos animais TO foi maior do que as dos demais, mostrando uma maior absorção... / The aim of this study was to compare the bioavailability of organic and inorganic selenium sources and their antioxidants functions in diets to dogs. Twentyfour male dogs were used and distributed in three treatments: control (TC-0,11 ppm of Se), inorganic (TI-0,30 ppm of sodium selenito) and organic (TO-0,30 ppm of Sel- Plex®). The experimental design was in a randomized blocks, the blocking factor was age. The experimental period was 80 days, the selenium balance trial was conducted at the first 10 days then the animals were transferred to kennels and the experiment lasted more 70 days. Feces, hair, urine, blood plasma and food were analyzed for selenium concentrations. The GSH-Px was determined in whole blood and at the 11th day a curve of selenium plasmatic absorption was conducted, the samples of blood plasma were obtained each 2 hours after feeding per 12 hours. The methodologies to access oxidative stress and antioxidant capacity were TBARS and total antioxidant capacity, respectively. The results were performed by analysis of variance and the means were compared by Tukey test (P≤0.05). For Se intake, fecal excretion of Se and Se retention, dogs from TC group showed lower values then TI and TO animals. There were no difference for urinary excretion of Se and Se bioavailability. For Se concentration in blood plasma the animals showed a higher value within 80 days even for animals from TC group. The concentration of selenium in hair increased within 80 days for animals from the TI and TO group. TO group had the major area under the curve differing statistically from the others groups showing a better absorption. The supplemented groups had the better values for GSH-Px activity. However, there were no significant differences among treatments for TBARS. For TAC there were no differences among the treatments, but during the experimental time the TAC values increased... (Complete abstract click electronic access below)
137

Problematika začlenění tenisu do vyučovacího procesu tělesné výchovy na základních školách\\ / Problems of tennis integration in physical education at elementary schools

VOŇAVKA, Petr January 2008 (has links)
My thesis is focused on the observation of possible reasons why tennis has not been included in education at elementary schools so far. The research work was performed using questionnaires at elementary schools in regions Vysocina and South Bohemia (December 2007 {--} February 2008). Theoretical {--} didactic part of thesis is focused on tennis history, physical and psychological severity of this sport, but mostly on availability of tennis in wide surroundings (in the view of number of tennis courts and costs for tennis equipment). There are compared particular regions in the research part of the thesis and their results are demonstrated in charts. The conclusions are summarised in discussion and in final part of thesis.
138

O gerenciamento e o suporte a aplicações em clusters de alta disponibilidades utilizando objetos distribuídos / Management and application support in high availability clusters using distributed objects

Claudio Roberto de Vincenzi 31 March 2003 (has links)
Este trabalho procura averiguar as dificuldades e os problemas envolvidos na especificação e implementação de uma arquitetura de objetos de serviço para gerenciamento e suporte a aplicações distribuídas em uma plataforma de computadores em configuração tipo cluster, em particular daqueles que devem cumprir requisitos de alta disponibilidade. Tal arquitetura deve apresentar-se como uma infra-estrutura distribuída de serviços e compor uma camada intermediária entre as partes das aplicações distribuídas e os recursos do cluster, compondo desse modo uma camada de middleware. Uma arquitetura de gerenciamento e de suporte a aplicações distribuídas, para que possa atingir plenamente seus objetivos, deve ser projetada como uma infra-estrutura distribuída de serviços de modo a oferecer acesso fácil e eficiente a estes. Neste trabalho, investigamos a possibilidade de se implementar tal infra-estrutura utilizando a arquitetura de objetos distribuídos OMG CORBA, a qual tem por objetivo facilitar a especificação, implementação e o acesso a interfaces de serviços de objetos distribuídos. Uma infra-estrutura de serviços de suporte a aplicações e de gerenciamento de cluster- é composta de dezenas de interfaces dos mais diversos tipos e finalidades, compondo vários sistemas e subsistemas distribuídos cujos serviços devem ser fácil e transparentemente acessíveis através da rede de comunicação que interconecta os nós do cluster. Essa rede tipicamente utiliza os protocolos de comunicação Ethernet IEEE 802.3, IP e TCP/UDP em seus níveis de enlace, rede e transporte, respectivamente. Por essa ótica, CORBA atende de antemão vários dos requisitos necessários, porém em diversos aspectos da arquitetura e dos serviços houve necessidade de se averiguar com mais profundidade a capacidade de CORBA de atendê-los. Como por exemplo, averiguou-se a capacidade de CORBA lidar com problemas ligados à falhas parciais de comunicação, comunicação em grupo, comunicação não-bloqueante e outras. Um dos desafios da abordagem utilizando CORBA reside no fato de que se tem o pré-requisito de alta disponibilidade. A arquitetura proposta deve ser projetada levando-se em conta que certas partes do sistema, tais como subsistemas de armazenamento, processamento, rede, aplicações e outros podem , a qualquer momento, falhar ou tornar-se inoperantes. O grande desafio deste trabalho consiste assim em averiguar quais são as dificuldades de se utilizar CORBA como parte central da arquitetura, uma vez que a infra-estrutura obtida necessita ser ela própria um conjunto de serviços de alta disponibilidade, caso contrário ela não conseguirá cumprir seus objetivos. Investigaremos então possíveis modos de implementação de objetos CORBA que venham a cumprir os requisitos de alta disponibilidade necessários. Por fim, este trabalho procura averiguar a possibilidade de se implementar tal arquitetura em clusters baseados em elementos de hardware e software disponíveis em larga escala e a baixo custo no mercado tais como PCs ou servidores baseados em processador Intel rodando os sistemas operacionais Linux ou FreeBSD e interconectados por redes locais de baixo custo. Tais plataformas são popularmente conhecidas como Beowulf Clusters. Este aspecto da investigação terá influência no projeto da arquitetura proposta, uma vez que procuramos enfocar aspectos de alta escalabilidade para o cluster, uma tendência para o uso desse tipo de cluster em aplicações de alta demanda de processamento e recursos, tais servidores web e de banco de dados de grandes provedores de conteúdo e serviços da Internet / This work intends to investigate for the difficulties and problems involved in the specification and implementation of an object-oriented architecture of services for management and support of distributed applications in a platform of computers in cluster configuration, in particular for those that must fulfill requirements of high availability. Such architecture must present itself as a infrastructure of distributed services and should compose an intermediate layer between the parts of the cluster distributed applications and the cluster resources, composing in this way a middleware layer. In order to reach its objectives, this support and management architecture must be designed as a distributed infrastructure of services. By this way, it can offer easy and efficient access to its services. In this text, we investigate the possibility of implementing such infrastructure of services using the distributed object architecture proposed by OMG, the so-called CORBA architecture. CORBA has many objectives and features as to facilitate the specification, implementation and access to distributed service objects. An infrastructure of services for the support and management of clusters and cluster applications is composed of a set of interfaces of the most diverse types and purposes, composing some distributed systems and subsystems whose services must be easy and transparently accessible through the communication networks that interconnects the cluster computer nodes. Cluster networks typically uses standard communication protocols such as Ethernet IEEE 802.3 at the data-link layer, the Internet Protocol (IP) at the network layer and TCP/UDP at the transport layer. In these aspects CORBA takes care on beforehand of severa1 of these requirements. However, for many service requirements of the proposed architecture it was necessary inquiring in more depth the CORBA capabilities to accomplish them. As an example, it was investigated the CORBA capabilities to deal with problems related to partial communication failures, communication for object groups, non-blocking and asynchronous communication and others. One of the challenges of the CORBA approach for the proposed architecture inhabits in the fact that the system must accomplish the prerequisite of high availability. The architecture proposal must be designed taking in account that certain parts of the system, such as storage subsystems, processors, network, applications and others can, at any time, fail or become inoperative. The great challenge of this proposal work consists thus inquiring the difficulties of adopting CORBA as a central part of the architecture, since the gotten infrastructure needss to be a proper high availability set of services. In contrary case, it will not fulfill its primary objectives. We will investigate possible ways of implementing CORBA objects in such a way that they fulfill the necessary high availability requirements. Finally, this work looks for the possibility of implementing the proposed system in clusters built with wide scale and low cost hardware and software elements available in the market, such as Intel-processor-based PCs and servers running open-source and low-cost operating systems such as Linux or FreeBSD and interconnected by low cost local area networks. Such platforms are popularly known as Beowulf Clusters. This aspect of The inquiry will have influence in the architecture proposal, once we are focusing aspects of high scalability for the cluster since there is a trend for the use of this type of cluster in applications of high demand of processing and resources, such as web servers for great suppliers of content and services on the Internet
139

ImportÃncia ClÃnica de um Estudo de BioequivalÃncia entre duas FormulaÃÃes de Diclofenaco SÃdico de LiberaÃÃo Prolongada

Marinus de Moraes Lima 09 August 2013 (has links)
CoordenaÃÃo de AperfeiÃoamento de Pessoal de NÃvel Superior / O diclofenaco sÃdico à um fÃrmaco anti-inflamatÃrio nÃo esteroidal, que exerce seus efeitos por meio da inibiÃÃo da cicloxigenase e modulaÃÃo do Ãcido araquidÃnico; apresenta propriedades analgÃsicas, sendo utilizado para tratamento sintomÃtico de dores, principalmente relacionadas à inflamaÃÃo. à um fÃrmaco de amplo uso e de fÃcil acesso para o usuÃrio. Um estudo de bioequivalÃncia refere-se à comparaÃÃo estatÃstica das principais medidas farmacocinÃticas observadas no experimento, relativas aos produtos a serem testados. Este estudo teve o objetivo de avaliar a bioequivalÃncia entre uma formulaÃÃo de diclofenaco sÃdico cÃpsulas de liberaÃÃo prolongada de 100 mg, chamada formulaÃÃo teste, versus uma formulaÃÃo de diclofenaco sÃdico cÃpsulas de liberaÃÃo prolongada de 100 mg, produto de referÃncia, em voluntÃrios sadios de ambos os sexos, em jejum e alimentados, conforme recomendaÃÃo da Anvisa. Ensaio clÃnico do tipo aberto, randomizado, cruzado, com quatro perÃodos, duas sequÃncias, nos quais os voluntÃrios receberam em cada perÃodo distinto em jejum ou alimentados, 01 cÃpsula de liberaÃÃo prolongada da formulaÃÃo teste ou 01 cÃpsula de liberaÃÃo prolongada de diclofenaco sÃdico 100 mg da formulaÃÃo de referÃncia. Em cada internaÃÃo, os voluntÃrios receberam a formulaÃÃo teste ou referÃncia acompanhada ou nÃo de uma dieta padrÃo especÃfica. As formulaÃÃes foram administradas em dose Ãnica, via oral, seguida de coletas de sangue, de pelo menos quatro meias-vidas do fÃrmaco em estudo. Os perÃodos de tratamento obedeceram a um intervalo de sete meias-vidas, entre eles (washout). As concentraÃÃes em plasma do Diclofenaco foram dosadas por mÃtodo analÃtico especÃfico e validado, baseados em cromatografia lÃquida de alta eficiÃncia acoplada à espectrometria de massa (LC-MS/MS). Os resultados mostraram que em relaÃÃo à ASCinf (Ãrea sobre a curva), os fÃrmacos nÃo foram bioequivalentes para a extensÃo da absorÃÃo. O pico de concentraÃÃo plasmÃtica (concentraÃÃo mÃxima), que indica velocidade de absorÃÃo do fÃrmaco, nÃo foi bioequivalente entre a formulaÃÃo teste e a formulaÃÃo referÃncia, estando fora do intervalo de confianÃa de 80-125%. Considerando o uso amplamente aberto do diclofenaco, ressalta-se a importÃncia em avaliar custo-eficiÃncia versus custo-efetividade quando se orienta o uso de determinada formulaÃÃo do mercado. A nÃo equivalÃncia terapÃutica pode comprometer o tratamento de um determinado sintoma, ou mesmo de uma doenÃa, podendo levar ao descrÃdito o fÃrmaco escolhido. à relevante observar que cada fÃrmaco responde a um indivÃduo de maneiras distintas, de acordo com as variaÃÃes biolÃgicas do mesmo, podendo ambas as formulaÃÃes testadas ser eficaz, mesmo nÃo sendo bioequivalentes. / Diclofenac sodium is a non-steroidal anti- inflammatory drug that exerts its effects through inhibition of cyclooxygenase and modulation of arachidonic acid; it has analgesic properties and is used for symptomatic treatment of pain, mainly related to inflammation. It is a drug widely used and easily accessible to the user. A bioequivalence study refers to the statistical comparison of the main pharmacokinetic measures observed in the experiment concerning to the products to be tested. This study aimed to evaluate the bioequivalence between a formulation of diclofenac sodium extended-release 100 mg capsules, called test formulation, versus a formulation of diclofenac sodium extended-release 100 mg capsules reference product, in healthy volunteers of both sex, fasted and fed, as recommended by ANVISA. Open-type Clinical trial, randomized , crossover, with four periods, two sequences, in which participants received in each distinct period in fasting or fed, 01 extended-release capsule of the test formulation or 01 extended release 100 mg capsule of diclofenac sodium of the reference formulation. In each hospitalization, the volunteers received the test or reference formulation with or without a specific diet pattern. The formulations were administered in a single oral dose, followed by blood sampling, at least four half-lives of study drug. Treatment periods obey an interval of seven half-lives, between then (washout). The diclofenac concentrations in plasma were dosed by a specific and validated analytical method based on liquid chromatography high efficiency coupled to mass spectrometry (LC-MS/MS). The results showed that with regard to AUCinf (area under the curve), the drugs were not bioequivalent to the extent of absorption. The peak plasma concentration (maximum concentration), which indicates the rate of absorption of the drug, was not bioequivalent between the test formulation and reference formulation, being outside the confidence interval of 80-125%. Considering the wide open use of diclofenac, it emphazises the importance of evaluate cost-efficiency versus cost-effectiveness when it guides the use of certain formulation of the market. The non therapeutic equivalence can compromise the treatment of a particular symptom, or even a disease, which may lead to discrediting the drug chosen. It is important to note that each individual responds to a drug in different ways, according to biological variations thereof, both formulations tested may be effective, although not bioequivalent.
140

Estudo de biodisponibilidade comparativa entre duas formulaÃÃes de cloridrato de metformina comprimidos revestidos de 850 mg, administradas a voluntÃrios sadios / Comparative bioavailability study formulations of metformin hydrochloride tablets administered to healthy volunteers

Edilson Martins Rodrigues Neto 25 February 2015 (has links)
CoordenaÃÃo de AperfeÃoamento de Pessoal de NÃvel Superior / O diabetes mellitus tipo 2 (DM2) à uma sÃndrome que pode ser definida como uma condiÃÃo de distÃrbios metabÃlicos heterogÃneos caracterizados por hiperglicemia resultante de defeitos na secreÃÃo e aÃÃo da insulina, ou ambos. A metformina à o fÃrmaco de primeira escolha para tratamento de DM2, sendo o anti-hiperglicemiante oral mais amplamente prescrito, devido ao seu perfil de toxicidade reduzida e eficÃcia clÃnica. Os estudos de biodisponibilidade apresentam diversas funÃÃes, entres elas podem-se listar: avaliaÃÃo da bioequivalÃncia de medicamentos, avaliaÃÃo de medicamentos com princÃpios ativos novos e avaliaÃÃo de novas formulaÃÃes. Este estudo teve o objetivo de avaliar a biodisponibilidade entre uma formulaÃÃo de cloridrato de metformina 850 mg em comprimidos revestidos, chamada formulaÃÃo teste, versus uma formulaÃÃo de referÃncia no mercado nacional com a mesma dose do fÃrmaco e mesma forma farmacÃutica, em voluntÃrios sadios de ambos os sexos. Trata-se de um ensaio clÃnico do tipo aberto, randomizado, cruzado, com dois perÃodos, duas sequÃncias, nos quais os voluntÃrios receberam em cada perÃodo distinto, 01 comprimido revestido da formulaÃÃo teste ou 01 da formulaÃÃo de referÃncia. As formulaÃÃes foram administradas em dose Ãnica, via oral, seguida de coletas de sangue, de pelo menos quatro meias-vidas do fÃrmaco em estudo. Os perÃodos de tratamento obedeceram a um intervalo de sete meias-vidas, entre eles (washout). As concentraÃÃes plasmÃticas de metformina foram dosadas por mÃtodo analÃtico especÃfico e validado, baseado em cromatografia lÃquida de alta eficiÃncia acoplada à espectrometria de massa (CLAE/EM). Os dados deste estudo revelaram que a formulaÃÃo teste e a formulaÃÃo referÃncia apresentaram resultados equivalentes, dentro dos limites de variaÃÃo previstos nas normativas reguladoras (80-125%) para os parÃmetros ASCinf (Ãrea sob a curva) e Cmax (concentraÃÃo sÃrica mÃxima do fÃrmaco). Desse modo, serà possÃvel garantir uma intercambialidade entre as formulaÃÃes, que poderà gerar competiÃÃo no mercado e consequentemente preÃos mais competitivos e facilidade de acesso ao medicamento. / Type 2 diabetes mellitus (DM2 is a syndrome which may be defined as a condition of heterogeneous metabolic disorder characterized by hyperglycemia resulting from defects in insulin secretion and action, or both. Metformin is the drug of choice for the treatment of type 2 diabetes, and it is the oral antihyperglyciemic most widely prescribed, due to their favorable toxicity profile and efficacy. Bioavailability studies have several functions including assessment of drugs bioequivalence, evaluation of drugs with new active principles and evaluating new formulations. This study aimed to assess the bioavailability of a formulation of metformin hydrochloride 850 mg film coated tablets, called test formulation, versus a reference formulation in the national market with the same dose of the drug in healthy volunteers of both genders. This is a clinical trial open-type, randomized, crossed, two-period, two-sequence, in which the volunteers received in each distinct period of 01 film coated tablet formulation of 01 test or reference formulation. The formulations were administered in a single oral dose, followed by blood sampling, at least four half-lives of study drug. The treatment periods obeyed an interval of seven half-lives, between them (washout). The metformin plasma concentrations were measured by a specific and validated analytical method based on high efficiency liquid chromatography coupled to mass spectrometry (HELC / MS). The data from this study reveal that the test formulation and the reference formulation showed similar results within the variation limits provided in the regulator norms (80-125%) for AUCinf (area under the curve) and Cmax (maximum serum concentration of drug). Thus, it will be possible ensure interchangeability between the formulations, which could lead to market competition and therefore more competitive prices and easy access to the drug.

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