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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.
91

Dancing on the Edge of the Word : Ursula K. Le Guin and Metaphor

Sheckler, Catherine 08 1900 (has links)
No description available.
92

L'échange génératif de technologies innovantes : engagement conceptif et conception de la valeur / The generative exchange of innovative technologies : design engagement and value design

Jean, Fabien 21 December 2016 (has links)
Dans leurs processus d’innovation, les grandes entreprises subissent un manque de ressources entre Recherche et Développement appelé vallée de la mort. Le groupe Safran s’est doté d’une direction de l’innovation afin de le compenser. Son fonctionnement est fondé sur une logique d'échange avec les sociétés du groupe. Mais dans les phases amont, lorsque les échanges comportent des inconnus, ils s’interrompent brutalement. En particulier des fiches idées issues de DKCP ne sont pas explorées. Cette recherche-intervention ambitionne donc d’établir un modèle d’action collective pour échanger dans l’inconnu. Elle défend la thèse que dans l’inconnu, vendeurs et acheteurs de technologies innovantes s’engagent dans la conception de la frontière entre des technologies et des environnements.Face aux limites des modèles d’échange marchand, de décision, d’intéressement et de créativité, cette thèse adopte un modèle d’échange intégrant l’inconnu et un cadre analytique issu des théories de la conception innovante. Elle propose le modèle de l’engagement conceptif de ressources. Elle explicite les limites de l'outil conventionnel d'échange de technologies dit Technology Readiness Levels adopté chez Safran. Elle propose alors de modéliser les échanges entre vendeurs et acheteurs de technologies comme l’exploration de la frontière Technologie-Environnement en suivant le formalisme C-K T / C-K E construit. Finalement la méthode Pilotage de l'Exploration Par les Invariants Technologie-Environnement (PEPITE) est élaborée avec la direction de l'innovation Safran sur la base de deux cas d’exploration ayant effectivement passé la vallée de la mort durant l’intervention des chercheurs. / Innovation processes of large companies experience a lack of resources between Research and Development, i.e. the valley of death. Safran created its Innovation Department to counterbalance. It is based on exchanges with the subsidiaries. However such exchanges cannot be processed in most early stages, when they include unknowns. For instance, ideas generated through the DKCP method remain unexplored. This intervention-research aims at establishing a model of collective action to exchange in the unknown. It defends the thesis that, in the unknown, sellers and buyers of innovative technologies engage in the design of the boundary between technologies and environments.Facing the limits of classic models of exchanges of economy, decision, intéressement and creativity, this thesis adopts a design-theories framework. It proposes the model of design engagement of resources. It explains the limits of a common tool for exchanging technologies, i.e. Technology Readiness Levels. It proposes to model exchanges between seller and buyer as the exploration of the Technology-Environment boundary. To do so it constructs the C-K T / C-K E formalism. Finally, the method Steering Exploration Through Technology and Environment Invariants ("Pilotage de l'Exploration Par les Invariants Technologie-Environnement" (PEPITE) in French) is constructed in collaboration with Safran Innovation Department. It is based on two cases of explorations which passed the valley of death within the researchers intervention.
93

Commande tolérante aux défauts et diagnostic des systèmes à retard inconnu par une approche sans modèle / Fault tolerant control and diagnosis of unknown delayed systems by a model-free approach.

Doublet, Maxime 03 December 2018 (has links)
Dans ce travail de thèse, la commande sans modèle a tout d'abord été appliquée et adaptée au cas des systèmes présentant un retard connu ou inconnu. Cette méthode de commande ne nécessitant pas la connaissance précise d'un modèle du système, elle trouve toute son efficacité dans l'appréhension de retards inconnus. Différentes adaptations de l'approche classique, reposant sur la minimisation de critères temporels et fréquentiels, ont été proposées suivant le contexte d'un retard connu, borné ou inconnu. Elles nous ont permis d'élargir le spectre des systèmes considérés et d'améliorer les performances intrinsèques de la commande sans modèle. Les systèmes retardés, qui sont la cible privilégiée de ce travail, ont pu bénéficier de ces améliorations. Le problème du diagnostic des systèmes à retard a ensuite été abordé. Une nouvelle méthode de diagnostic sans modèle a été proposée, fondée sur les principes mêmes de la commande sans modèle. Cette proposition s'appuie sur la seule évolution temporelle des signaux entrée/sortie du système. Par la génération de signaux résiduels, la détection et la localisation de défauts d'actionneurs et du système est assurée sous certaines hypothèses. Finalement, nous avons montré en quoi la commande sans modèle s'apparente à une commande tolérante aux défauts et son efficacité en tant que telle a été prouvée. Une différence importante est à souligner par comparaison à d'autres commandes plus classiques, de type PI par exemple. En effet, la commande sans modèle est non seulement robuste à des signaux perturbateurs basses fréquences en entrée, à l'identique d'une structure PI classique, mais elle permet également de rejeter d’autres types de signaux révélateurs de défauts via l’estimation de certains paramètres de synthèse. Tout au long du mémoire, l'efficacité des approches proposées en commande et en diagnostic est perçue au travers d'exemples académiques / In this thesis, the model-free control was applied and adapted to delayed systems whose delay is either known or unknown. This method of control does not require the specific knowledge of a model of the system, it finds all its effectiveness in the apprehension of the unknown delays. Different adaptations of the classical approach, based on the minimization of frequency and temporal criteria, have been proposed in the context of a known, bounded or unknown delay. They allowed us to extend the range of systems considered and to improve the intrinsic performance of the model-free control. The delayed systems, which are the main target of this thesis, were able to benefit from these improvements. The problem of the fault-diagnosis of delayed systems was then addressed. A new method of model-free diagnosis has been proposed, based on model-free control principles. Our proposal only uses the temporal evolution of the system's input and output signals. Due to the generation of residual signals, the detection and localization of actuator/system faults were permitted under certain assumptions. Finally, we have studied the fault-tolerance properties of model-free control and its efficacy has been proven. Compared with more conventional methods, such as the PI Controller for example, a notable difference is to be mentioned. Indeed, unlike a PI controller, the model-free control is robust not only to low-frequency input disturbance signals, but it also allows for the rejection of other signal types by estimating summary parameters. Throughout this report, the effectiveness of the proposed approaches was illustrated in terms of control or diagnosis by multiple academic examples
94

O conceito de douta ignorância de Nicolau de Cusa em uma perspectiva pedagógica / The concept of learned ignorance of Nicholas of Cusa in a pedagogical perspective

Guendelman, Constanza Kaliks 17 March 2009 (has links)
O aprendizado muitas vezes se encontra vinculado à idéia de que é necessário superar o estado de desconhecimento, de não-saber, para alcançar o saber enquanto instância almejada. No presente trabalho, estudamos o conceito de douta ignorância desenvolvido por Nicolau de Cusa por acreditar que ele encerra uma dimensão essencialmente pedagógica que se revela na importância que esse filósofo do século XV dá ao não-saber. Para ele, a busca pelo conhecimento está inteiramente alicerçada na ciência que o homem alcança de sua própria ignorância. É o saber de seu não-saber que permite que o ser humano construa, de forma progressiva, o conhecimento. A concepção de conhecimento à qual subjaz uma imagem dinâmica de ser humano como a que encontramos em Nicolau de Cusa retorna em pensadores contemporâneos. Bachelard, por exemplo, no século XX, reafirma a positividade dos erros, defendendo a sua importância na construção do saber científico e no processo de aprendizagem. Aquilo que, no discurso comum, era apontado apenas como intercorrência a ser evitada, passa a ser revalorizado, resgatando uma tradição que acreditamos ter em Nicolau de Cusa um expoente fundacional. Nosso trabalho busca apresentar uma abordagem positiva desses dois elementos constitutivos do aprender o não-saber e o erro , considerados parte de um processo que entra em movimento quando o professor permite que o aluno exercite o ato de formular perguntas: na formulação de uma pergunta está contido o potencial de ir além de um saber já adquirido, de superar dificuldades ou erros. A pergunta abre a perspectiva do conhecimento e aponta para o que ainda está por ser alcançado. Ela é, assim, um veículo para a continuidade do aprendizado. / Learning finds itself many times tied to the idea that it is necessary to surmount the state of ignorance, of unknowing, in order to achieve knowledge as a yearned instance. In the present work, we studied the concept of learned ignorance developed by Nicholas of Cusa due to our belief that it contains an essential pedagogic dimension which reveals itself in the importance this philosopher from the XV century confers to the unknown. According to him, the search for knowledge is entirely based on the science man acquires of his own ignorance. It is the knowledge of what is unknown that allows the human being to build knowledge progressively. The conception of knowledge to which underlies a dynamic image of the human being reassembles in contemporary thinkers. In the XX century, Bachelard, for instance, reaffirms the mistake positivity, defending its importance to the construction of scientific knowledge in the process of learning. What, in the common discourse, was cited merely as intercurrence starts to be revalued, recovering a tradition we believe has in Nicholas of Cusa a founding exponent. Our work aims to present a positive approach of these two learning constitutive elements the unknown and the mistake considered, in this tradition, part of a process that begins its movement when the teacher allows the student to practice the act of formulating questions: within the formulation of a question is contained the potential to go beyond an acquired knowledge, to surmount difficulties or mistakes. The question widens the perspective of knowledge and indicates what is yet to be achieved. It is, therefore, a means for the resumption of learning.
95

L’affectif, les valeurs et le matching dans les choix des investisseurs individuels en incertitude : le cas de l’equity crowdfunding / Affective, values and matching in individual investors choices in uncertainty : the case of equity crowdfunding

Goglin, Christian 14 December 2018 (has links)
Notre recherche s’intéresse aux déterminants affectifs et axiologiques du choix d’investissement en equity crowdfunding. Nous défendons la thèse d’un choix de projets déterminé en partie par les valeurs et l’affectif de l’investisseur individuel. Notre revue de littérature est transversale à plusieurs champs des sciences sociales. Ainsi, le cadre théorique établi articule finance, marketing, GRH et psychologie. Un modèle explicatif par équations structurelles est proposé puis testé empiriquement grâce aux données d’une expérimentation de laboratoire. Nos résultats confirment que les valeurs ainsi que l’intérêt pour le projet, une variable affective, ont un effet sensible dans les choix des investisseurs et dominent le jugement analytique en l’absence d’interactions sociales réelles et virtuelles. Une théorie originale est proposée pour améliorer la compréhension du phénomène étudié, au-delà des apports de la théorie du signal. Cette théorie, le matching affectif, personnalise les comportements et offre un prisme de lecture reposant sur la congruence entre caractéristiques du projet et préférences de l’investisseur. Sa mise en œuvre par un modèle dérivant du modèle explicatif associé à une mesure de similarité ad hoc produit des résultats prédictifs encourageants. Notre travail se termine par un ensemble de suggestions managériales découlant de nos conclusions / Our research focuses on the emotional and axiological determinants of investment choice in equity crowdfunding. We defend the thesis of a projects choice determined in part by the values and emotions of the individual investor. Our literature review is transversal to several fields of social sciences. Thus, the established theoretical framework articulates finance, marketing, HRM and psychology. An explanatory model using structural equations is proposed and tested empirically using data from a laboratory experiment. Our results confirm that values and interest in the project, an affective variable, have a significant effect on investor choices and dominate analytical judgment in the absence of real and virtual social interactions. An original theory is proposed to improve the understanding of the studied phenomenon, beyond the contributions of the signal theory. This theory, emotional matching, personalizes behaviors and offers a prism of reading based on the congruence between characteristics of the project and investor preferences. Its implementation by a model derived from the explanatory model associated with an ad hoc similarity measure produces encouraging predictive results. Our work ends with a set of managerial suggestions arising from our findings.
96

Estimation en temps fini de systèmes non linéaires et à retards avec application aux systèmes en réseau / Finite-time estimation of nonlinear and delay systems with application to networked systems

Langueh, Kokou Anani Agbessi 06 December 2018 (has links)
Cette thèse étudie le problème d'identification de la topologie d'un réseau de systèmes complexes dynamiques, dont les sous-systèmes sont décrits par des équations différentielles ordinaires (EDO) et/ou par des équations différentielles à retard (EDR). La première partie de ce travail porte sur l’identification des paramètres du réseau de systèmes linéaires. Ainsi, différentes classes de systèmes linéaires ont été traitées, à savoir les systèmes sans retard, les systèmes à retard commensurable et les systèmes à entrées inconnues. Un observateur impulsif est proposé afin d'identifier à la fois les états et les paramètres inconnus de la classe de système dynamique considérée en temps fini. Afin de garantir l'existence de l'observateur impulsif proposé, des conditions suffisantes sont déduites. Des exemples illustratifs sont donnés afin de montrer l'efficacité de l'observateur en temps fini proposé.La deuxième partie de ce travail traite le problème de l'identification de la topologie d'un réseau de systèmes dynamiques non linéaires. Dans nos considérations, les coefficients interconnexions de la topologie du réseau sont considérés comme des paramètres constants. Par conséquent, l'identification de la topologie est équivalente à l'identification des paramètres inconnus. Tout d’abord, nous avons déduit des conditions suffisantes sur l’identifiabilité des paramètres, puis nous avons proposé un différenciateur uniforme avec convergence en temps fini pour estimer les paramètres inconnus / This thesis investigates the topology identification problem for network of dynamical complex systems, whose subsystems are described by ordinary differential equations (ODE) and/or delay differential equations (DDE). The first part of this work focuses on the parameters identification of the network of linear systems. Thus, different classes of linear systems have been treated namely systems without delay, systems with commensurable delay and systems with unknown inputs. An impulsive observer is proposed in order to identify both the states and the unknown parameters of the considered class of dynamic system in finite time. In order to guarantee the existence of the proposed impulsive observer, sufficient conditions are deduced. An illustrative example is given in order to show the efficiency of the proposed finite-time observer.The second part of this work treats the topology identification of the network of nonlinear dynamic systems. In our considerations, the topology connections are represented as constant parameters, therefore the topology identification is equivalent to identify the unknown parameters. A sufficient condition on parameter identifiability is firstly deduced, and then a uniform differentiator with finite-time convergence is proposed to estimate the unknown parameters
97

O conceito de douta ignorância de Nicolau de Cusa em uma perspectiva pedagógica / The concept of learned ignorance of Nicholas of Cusa in a pedagogical perspective

Constanza Kaliks Guendelman 17 March 2009 (has links)
O aprendizado muitas vezes se encontra vinculado à idéia de que é necessário superar o estado de desconhecimento, de não-saber, para alcançar o saber enquanto instância almejada. No presente trabalho, estudamos o conceito de douta ignorância desenvolvido por Nicolau de Cusa por acreditar que ele encerra uma dimensão essencialmente pedagógica que se revela na importância que esse filósofo do século XV dá ao não-saber. Para ele, a busca pelo conhecimento está inteiramente alicerçada na ciência que o homem alcança de sua própria ignorância. É o saber de seu não-saber que permite que o ser humano construa, de forma progressiva, o conhecimento. A concepção de conhecimento à qual subjaz uma imagem dinâmica de ser humano como a que encontramos em Nicolau de Cusa retorna em pensadores contemporâneos. Bachelard, por exemplo, no século XX, reafirma a positividade dos erros, defendendo a sua importância na construção do saber científico e no processo de aprendizagem. Aquilo que, no discurso comum, era apontado apenas como intercorrência a ser evitada, passa a ser revalorizado, resgatando uma tradição que acreditamos ter em Nicolau de Cusa um expoente fundacional. Nosso trabalho busca apresentar uma abordagem positiva desses dois elementos constitutivos do aprender o não-saber e o erro , considerados parte de um processo que entra em movimento quando o professor permite que o aluno exercite o ato de formular perguntas: na formulação de uma pergunta está contido o potencial de ir além de um saber já adquirido, de superar dificuldades ou erros. A pergunta abre a perspectiva do conhecimento e aponta para o que ainda está por ser alcançado. Ela é, assim, um veículo para a continuidade do aprendizado. / Learning finds itself many times tied to the idea that it is necessary to surmount the state of ignorance, of unknowing, in order to achieve knowledge as a yearned instance. In the present work, we studied the concept of learned ignorance developed by Nicholas of Cusa due to our belief that it contains an essential pedagogic dimension which reveals itself in the importance this philosopher from the XV century confers to the unknown. According to him, the search for knowledge is entirely based on the science man acquires of his own ignorance. It is the knowledge of what is unknown that allows the human being to build knowledge progressively. The conception of knowledge to which underlies a dynamic image of the human being reassembles in contemporary thinkers. In the XX century, Bachelard, for instance, reaffirms the mistake positivity, defending its importance to the construction of scientific knowledge in the process of learning. What, in the common discourse, was cited merely as intercurrence starts to be revalued, recovering a tradition we believe has in Nicholas of Cusa a founding exponent. Our work aims to present a positive approach of these two learning constitutive elements the unknown and the mistake considered, in this tradition, part of a process that begins its movement when the teacher allows the student to practice the act of formulating questions: within the formulation of a question is contained the potential to go beyond an acquired knowledge, to surmount difficulties or mistakes. The question widens the perspective of knowledge and indicates what is yet to be achieved. It is, therefore, a means for the resumption of learning.
98

Conhecimentos relativos à variável, mobilizados por professores da educação básica

Queiroz, Paulo César Galvão 12 May 2008 (has links)
Made available in DSpace on 2016-04-27T16:58:38Z (GMT). No. of bitstreams: 1 Paulo Cesar Galvao Queiroz.pdf: 2390276 bytes, checksum: b2ee7b48c11fc869cbbda01186aa6cf9 (MD5) Previous issue date: 2008-05-12 / Secretaria da Educação do Estado de São Paulo / In this research we search to investigate the knowledge mobilized for the professors in whom if they relate to the variable and its different uses. We look for to verify where knowledge, the professors in such a way of basic education as average, express on this concept, as for its interpretation, symbolization and manipulation in accordance with the express theoretical recital in model 3UV (three uses of the variable), main tool of analysis of the gotten data. The empirical part of our research was based on the application of a pilot questionnaire who consists later of fifteen questions and, of a definitive questionnaire that consists its turn of eight questions. They had been studied by way of this last device, the answers of fifteen professors who acted in four schools of the Basic Education being three of public education, of which one of them of education technician and another one of particular education, all located in the city of São Paulo. With relation to the questionnaire, the same it consisted of problems in natural language, resolution of algebraic expressions, situations that involve given tabular and others that approached graphs. According to model 3UV, the variable acts depending on the proposal for the situation to be explored as: unknown term, generic number or variable in functional relationship. These criteria of the variable in its different papers had been analyzed second to the symbolization, manipulation and interpretation. In accordance with the gotten data, we conclude that the professors had demonstrated difficulties in that if he relates to the interpretation and the symbolization of the variable in functional relationship, being that the symbolization of referring situations to the variable as generic number had also presented problems, however in a lesser level. In relation to the variable that act as unknown term, few difficulties had been observed. In a general way, the research showed that the variable concept can represent a source of obstacles for education and learning of slight knowledge that on it depend, as: function, limit, derivative, integral..., a time that the difficulties that the proper professors present in the interpretation of the components that involve such concept, indicate that its education is not trivial / Nesta pesquisa buscamos investigar os conhecimentos mobilizados pelos professores no que se refere às variáveis e suas diferentes utilizações. Procuramos verificar que conhecimentos, os professores tanto do ensino fundamental como médio, expressam sobre este conceito, no que se refere a sua interpretação, simbolização e manipulação de acordo com a fundamentação teórica expressa no modelo 3UV (três usos das variáveis), principal ferramenta de análise dos dados obtidos. A parte empírica de nossa pesquisa baseou-se na aplicação de um questionário piloto que consta de quinze questões e posteriormente, de um questionário definitivo que consta a seu turno de oito questões. Foram estudadas por meio deste último dispositivo, as respostas de quinze professores que atuavam em quatro escolas da Educação Básica sendo três de ensino público, da qual uma delas de ensino técnico e outra de ensino particular, todas localizadas na cidade de São Paulo. Com relação ao questionário, o mesmo constava de problemas em linguagem natural, resolução de expressões algébricas, situações que envolvem dados tabulares e outras que abordavam gráficos. Segundo o modelo 3UV, as variáveis atuam dependendo da proposta pela situação a ser explorada como: termo desconhecido, número genérico ou variáveis em relacionamento funcional. Estes critérios da variável em seus diferentes papéis foram analisados segundo à simbolização, manipulação e interpretação. De acordo com os dados obtidos, concluímos que os professores demonstraram dificuldades no que se refere à interpretação e à simbolização das variáveis em relacionamento funcional, sendo que a simbolização de situações referentes às variáveis como número genérico também apresentaram problemas, porém em um nível menor. Em relação às variáveis que atuam como termo desconhecido, foram observadas poucas dificuldades. De um modo geral, a pesquisa mostrou que o conceito de variável pode representar uma fonte de obstáculos para o ensino e aprendizagem de noções que dele dependem, como: função, limite, derivada, integral,..., uma vez que as dificuldades que os próprios professores apresentam na interpretação dos componentes que envolvem tal conceito, indicam que seu ensino não é trivial
99

A compreensão de alunos, ao final do ensino médio, relativa ao conceito de variável

Rodrigues, Daniela Milaneze 18 November 2008 (has links)
Made available in DSpace on 2016-04-27T16:58:48Z (GMT). No. of bitstreams: 1 Daniela Milaneze Rodrigues.pdf: 6569340 bytes, checksum: e50963d2dd92e9ebd4ba8aa9d8e06d24 (MD5) Previous issue date: 2008-11-18 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The aim of this research was to investigate the third year of high school students´ comprehension of the concept of variable. For its development, it was used a theoretical framework called 3UV model formulated by researchers Trigueros e Ursini (2001). The model involves a decomposition of the concept of variable in its three main uses in elementary algebra unknown, general number and related variables, that is, variables in functional relationship and the essential abilities to comprehend each of them to acquire the concept of variable. This theoretical framework was used as guideline in the design of a questionnaire with 22 items, in which the three uses of variable were used. The questions demanded the capabilities of symbolization, manipulation and interpretation from the students related to the three uses of variable, jointly with the mobilization of the abilities that the 3UV model suggests. According to data collected, through the questionnaire and the interviews, which were realized after the application of the first, it was noticed that the students didn t show difficulties to interpret, symbolize and manipulate the variable as unknown. On the other hand, the comprehension of the variable as a general number and as related variables showed gaps related directly to the lack of mobilization of some abilities of manipulation and interpretation present in the 3UV model as needed abilities to the comprehension of the concept. Thus, this investigation helped to point up the difficulties of the students to deal with problems related to concept of variable and to indicate the abilities that should be better worked, in the teaching process of the concept of variable, to provide its comprehension / A presente pesquisa teve como objetivo investigar a compreensão de alunos do terceiro ano do Ensino Médio a respeito do conceito de variável. Para o seu desenvolvimento, foi utilizada uma ferramenta teórico-metodológica denominada modelo 3UV, elaborada pelas pesquisadoras Trigueros e Ursini (2001). Tal modelo apresenta uma decomposição do conceito de variável em seus três principais usos em álgebra elementar - incógnita, número genérico e variáveis relacionadas, ou variáveis em relação funcional e as habilidades essenciais à compreensão de cada um deles para a aquisição do conceito de variável. Essa ferramenta serviu como guia na elaboração de um questionário contendo 22 itens, envolvendo o emprego dos três usos da variável. As questões formuladas exigiram as capacidades de simbolização, manipulação e interpretação dos alunos relativas à variável em seus três usos, juntamente com a mobilização das habilidades sugeridas no modelo 3UV. Com base nos dados coletados, por meio do questionário e das entrevistas realizadas após sua aplicação, observou-se que os estudantes não apresentaram dificuldades em interpretar, simbolizar e manipular a variável como incógnita. Por outro lado, a compreensão da variável como número genérico e em relação funcional demonstrou lacunas, as quais estão diretamente relacionadas à falta de explicitação de algumas das habilidades específicas de manipulação e de interpretação apresentadas no modelo 3UV como necessárias à compreensão do conceito. Dessa forma, tal investigação possibilitou o apontamento de dificuldades dos alunos ao lidar com problemas em que o conceito de variável fazia-se presente, indicando, para o desenvolvimento de futuras pesquisas, as habilidades que deveriam ser melhor exploradas no processo de ensino para favorecer sua compreensão
100

Immunhistochemisch gestützte Tumordiagnostik unter besonderer Berücksichtigung von Metastasen bei unbekanntem Primärtumor

Kaufmann, Olaf 06 November 2001 (has links)
Immunhistochemische Zusatzuntersuchungen an Karzinommetastasen mit unbekanntem Primärtumor sind kostengünstig und erlauben insbesondere bei Adenokarzinomen oft eine spezifische Identifizierung des primären Tumorsitzes. Die Auswahl an kommerziell verfügbaren Antikörpern gegen Markerproteine mit gut dokumentierter hoher bis sehr hoher Spezifität für bestimmte Primärtumoren ist jedoch begrenzt. Dazu gehören der Thyreoidale Transkriptionsfaktor-1, Uroplakin III, GCDFP-15, Östrogen- und Progesteronrezeptoren, (-Fetoprotein, der A103-Antikörper gegen MART-1, die Cytokeratine 7 und 20, Basalzell-Cytokeratine, das carcinoembryonale Antigen, CA-125, EMA, Vimentin, HepPar-1, PSA, Thyreoglobulin und das S100-Protein. Die meisten dieser Marker sind jedoch nicht absolut spezifisch, die mit ihnen erzielten Färbeergebnisse müssen daher im Kontext des klinischen und konventionell-histomorphologischen Gesamtbefundes bewertet werden. Je genauer im Rahmen dieses Gesamtbefundes das Spektrum der infrage kommenden Karzinome und ihre relativen a priori Wahrscheinlichkeiten abgeschätzt werden, um so genauer lassen sich auch auf der Grundlage des Bayes-Theorems aus den Färbeergebnisse der Marker diagnostisch relevante Aussagen (prädiktive Werte) gewinnen. / Immunohistochemical studies on metastatic carcinomas of unknown primary site are cost-effective and often allow a specific identification of the tumor origin, especially if the metastases are adenocarcinomas by light microscopy. Commercially available site-specific markers include prostate-specific antigen, thyreoglobulin, thyreoid transcription factor-1, uroplakin III, GCDFP-15, estrogen- and progesterone rezeptors, (-Fetoprotein, the A103 monoclonal antibody against MART-1, cytokeratins 7 and 20, cytokeratins of basal cell type, p63, carcinoembryonic antigen, CA-125, EMA, vimentin, HepPar-1, and S100 protein. However, immunostainings with most of these markers do not show an absolute specificity for a certain primary site. For this reason, histopathologists interpretating staining results with these markers should take into consideration the available clinical data and the histological features of the metastatic carcinoma. These data are necessary to estimate the relative a priori probabilities of possible carcinomas. Based on Bayes` theorem, the a priori probabilities can then be used to calculate the diagnostically relevant predictive values for immunostaining results with the chosen markers.

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