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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.
211

Transplantace kostní dřeně, její historický vývoj a současné trendy / Bone marrow transplantation, its historical development and current trends

CIMBÁLNÍKOVÁ, Eva January 2019 (has links)
The transplantation of bone marrow - more generally said of hematopoietic cells - is in the present time one of the modern therapeutical methods used in cases of malfunction of haematogenesis inside of the bone. The ususal reason for going through with transplantation is leukemia, lymphomas, also anemia, congenital metabolic disorders, autoimmune disorders or some of the solid tumors. Thanks to the transplantation of hematopoietic cells, it is possible to highten the chance of restoration in more than 50 % of patients suffering from oncological disease. The submitted thesis is processed in theoretical form, it is goal is to present the important points leading to progress of this presently very much used treatment and also thorough descripton of present trends in the area of transplantation of hematopoietic cells, that are almost identical in local transplatation centers as they are in the world. Another goal is to describe the role of a general nurse during providing of the care for a patient before and after transplantation of hematopoietic cells. The thesis is focused on the key areas of the issues of transplatation of hematopoietic cells and it is divided into several parts. The first part deals with the general description of the topic, it presents short introduction into the transplantation of hematopoietic cells, the basic division, historical and current indications and short preamble into todays trends. It describes closely the area of the registry of the bone marrow donors, which is the basics for the choosing of the suitable unrelated donor. The second part of the thesis deals with the desciption of historical progress since the very beginnings, through the progress during postwar period, the development of 70s and 80s of the previous century and also the 90s of the 20th century up until the present day. The third part is focused on current methods of collection of hematopoietic cells and following transplatation, it also describes closely the ways of donating hematopoietic cells, the preparation of the patient for transplantation, the course of transplantation and what should the patient prepare for during the early posttransplantation period. The fourth part is focused on nursing, it states thoroughly the role of a nurse in the nursing care before and after transplantation of hematopoietic cells, the principles a nurse has to abide by, and it also closely describes the role of a nurse during transplant application. It also describes dietary and important regimen measures the patient is set to follow after transplantation. The last part is focused especially on complications that are possible after hemopoetic cells transplantation. The necessary data have been obtained through thorough study of professional Czech and foreign monoghraphs and scientific periodicals. The acquisition of the data was significantly contributed to by the attended internsip in Internal hematological and oncological clinic of the Faculty hospital Brno Bohunice. The findings regarding nursing were obtained especially by the study of nursing standards. This thesis points out the important role of transplatation of hemopoetic cells as a method of treatment predominantly of hemooncological illnesses in current medicine and the most important roles of a nurse during the nursing of transplantation patients. The thesis provides a comperehensive overview on the issue of transplants of the hematopoietic cells and describes key areas that are considered as important. It focuses on the historical progress and the desciption of present trends thanks to which the transplantology can be considered as a highly professional and top field. It also highlights the main roles of a nurse during nursing that must be proffesional, qualified, meticulous, considerate and individualized. The results of the survey are supposed to provide the professional and amateur public enough information about the issue of transplantation of the hematopoietic cells.
212

The bone marrow microenvironment in myelodysplastic syndromes : functional and molecular study / Le microenvironnement médullaire au cours des syndromes myélodysplasiques : étude fonctionnelle et moléculaire

Goulard, Marie 28 September 2017 (has links)
Les syndromes myélodysplasiques (MDS) sont un groupe de pathologies myéloïdes caractérisées par une hématopoïèse inefficace. Le rôle du microenvironnement médullaire (MM) dans l’histoire naturelle de ces pathologies reste incertain. Des anomalies du MM ont été décrites au cours des myélodysplasies et des modèles murins récemment publiés font penser qu’une altération du MM pourrait jouer un rôle dans le déclenchement et/ou l’évolution de ces maladies.Nous avons tenté de développer un modèle in vivo récapitulant l’histoire naturelle des myélodysplasies par des xénogreffes chez des souris NSG et NSG-S. Le faible taux de prise de greffe nous a amenés à développer un modèle in vitro de co-culture en 2D. Ce modèle est une bonne alternative pour les études de nouvelles stratégies thérapeutiques pour les patients atteints de myélodysplasies.Au cours de ce travail, nous avons également réalisé une étude systématique du stroma médullaire de patients atteints de syndromes myélodysplasiques dans le but d’identifier les anomalies fonctionnelles et moléculaires des cellules souches mésenchymateuses (CSMs), cellules centrales du MM pour leur interaction avec les cellules souches hématopoïétiques (CSHs).Les CSMs de MDS ont une clonogénécité diminuée. Nous n’avons pas observé de modification significative de leurs capacités de différenciation en ostéoblastes, adipocytes et chondrocytes ni dans leur capacité à supporter une hématopoïèse normale. Les CSMs de MDS présentent des modifications au niveau épigénétique et transcriptionnel pouvant expliquer l’altération des relations observées grâce à de l’imagerie enregistrée entre les CSMs de MDS et les CSHs dans un modèle de co-culture en 3D.Ces résultats montrent que les CSMs de MDS ont des modifications fonctionnelles et moléculaires et que ces anomalies perturbent leur relation avec les CSHs. / Myelodysplastic syndromes (MDS) are a heterogeneous group of clonal myeloid pathologies characterized by an impaired hematopoiesis. The role of the bone marrow microenvironment (BMM) remains unclear in the natural history of these diseases. Abnormalities of the BMM have been observed in myelodysplasia and a recent published murine model implies that alterations of the BMM could play a role in the trigger/progression of these diseases.Firstly, we tried to develop an in vivo model of MDS in NSG and NSG-S mice. The low rate of engraftment pushed us to develop a 2D co-culture model in vitro. This model is a good alternative to test new therapeutic strategies for MDS patients.In this study, we analysed mesenchymal stromal cells (MSCs) from the bone marrow of pretreated MDS patients in order to identify the functional and molecular abnormalities in those cells of the BMM, central for their interactions with the hematopoietic stem cells (HSCs).MDS MSCs have an impaired clonogenic capacity. We didn’t observed modifications of their differentiation toward osteogenic, adipogenic and chondrogenic pathways and capacity to support of a normal hematopoiesis. MDS MSCs display epigenetic and transcriptomic modifications that could explain the alteration of the relationships between these cells and HSCs observed in imagery in a 3D co-culture model.These results showed that MDS MSCs have functional and molecular abnormalities and that these alterations could impair their relationship with HSCs.
213

Detecção e manejo de disfunções cardíacas em pacientes com esclerose sistêmica tratados com altas doses de ciclofosfamida seguidas por transplante de células-tronco hematopoéticas / Detection and management of cardiac disfunction in patients with systemic sclerosis treated with high dose cyclophosphamide followed by hematopoietic stem cell transplantation

Leopoldo, Vanessa Cristina 17 December 2018 (has links)
O transplante autólogo de células-tronco hematopoéticas (TACTH) é efetivo para o tratamento da esclerose sistêmica (ES), com controle do acometimento pulmonar, e melhora da fibrose cutânea, da qualidade de vida e aumento da sobrevida global, quando comparado a pacientes não transplantados. Neste tratamento, utiliza-se ciclofosfamida em altas doses, uma droga imunossupressora associada a cardiotoxicidade, potencialmente fatal. A avaliação de potenciais fatores de risco e monitorização clínica durante o procedimento podem contribuir para identificar precocemente a lesão cardíaca aguda e, assim, melhorar o desfecho clínico do paciente. O objetivo deste estudo foi identificar a ocorrência de disfunções cardíacas e avaliar os fatores de risco clínicos e laboratoriais para o desenvolvimento de toxicidade cardíaca aguda induzida pela ciclofosfamida, em pacientes com ES submetidos ao TACTH. Trata-se de um estudo longitudinal e prospectivo, conduzido no Hospital das Clínicas da Faculdade de Medicina de Ribeirão Preto, em pacientes com ES com idade superior a 18 anos, no período de novembro de 2016 a maio de 2018, aprovado por Comitê de Ética em Pesquisa. Os pacientes foram avaliados quanto aos dados clínicos e laboratoriais, incluindo dosagem de peptídeo natriurético, no período pré, durante e 6 meses após o transplante. Foram incluídas 16 mulheres com ES, das quais uma optou por descontinuar a participação no estudo, tendo seus dados excluídos. Nenhum dos participantes apresentava história de uso de substâncias psicoativas ou diagnóstico de diabetes mellitus. Uma paciente era tabagista passiva e uma era tabagista ativa há 24 anos, abstinente desde há três meses antes do início do transplante. Duas pacientes eram hipertensas, controladas com medicamentos anti-hipertensivos. Durante o transplante, 7 (46,7%) pacientes apresentaram alterações cardíacas associadas à ciclofosfamida. As pacientes apresentaram taquicardia, ganho ponderal, aumento de pressão venosa central e dispneia iniciados em menos de 24 horas e até 4 dias após o término da infusão da dose total de ciclofosfamida (200mg/kg) do transplante. Em três, de cinco pacientes submetidas a ecocardiografia, foram detectadas alterações sugestivas de disfunção cardíaca, corroborando os achados clínicos. Uma paciente evoluiu com choque refratário e posterior óbito por falência múltipla de órgãos. Uma paciente necessitou de pericardiocentese de alívio e, nos demais, o manejo com medicações reverteu as alterações clínicas. A dosagem dos níveis séricos de peptídeo natriurético mostrouse mais elevada (p<0,0005) nos pacientes que apresentaram sinais de toxicidade cardíaca. Concluímos que as avaliações clínicas sistematizadas por equipe de enfermagem permitiram a detecção de disfunções cardíacas pós-infusão de altas doses de ciclofosfamida, quadros retrospectivamente comprovados por elevação dos níveis sérico de peptídeo natriurético. O número reduzido de participantes não permitiu fazer análises estatísticas preditoras de cardiotoxicidade e foi uma limitação do estudo. Futuramente, objetivamos aumentar o número de pacientes do estudo e identificar marcadores preditivos de toxicidade cardíaca antes e durante o transplante / Autologous hematopoietic stem cell transplantation (AHSCT) is effective for the treatment of systemic sclerosis (SSc), with stabilization of pulmonary involvement and improvement of cutaneous fibrosis, quality of life and overall survival, when compared to non-transplanted patients. Transplant includes high dose cyclophosphamide, an immunosuppressive drug associated with potentially fatal cardiotoxicity. The evaluation of potential risk factors and clinical monitoring during the procedure may contribute to early identification of acute cardiac injury and thus improve the patient\'s clinical outcome. The aim of this study was to detect cardiac dysfunctions and to evaluate clinical and laboratory risk factors for the development of acute cardiac toxicity induced by cyclophosphamide in SSc patients submitted to AHSCT. This is a longitudinal and prospective study, conducted in the University Hospital of the Ribeirão Preto Medical School (Brazil), in patients with SSc, older than 18 years of age, from November 2016 to May 2018. The protocol has been approved by the Institutional Research Ethics Committee and all patients signed informed consent. Patients were evaluated for clinical and laboratory data, including natriuretic peptide dosage before, during and at the 6 months post-transplant time point Sixteen women with SSc were included, one of whom chose to discontinue participation in the study, having their data excluded. None of the participants had a history of psychoactive substance abuse or a diagnosis of diabetes mellitus. One patient was a passive smoker and another, an active smoker for 24 years, not smoking in the three months before transplantation. Two patients had their blood pressure controlled with antihypertensive drugs. During transplantation, 7 (46.7%) patients had cardiac changes associated with cyclophosphamide. The patients presented tachycardia, weight gain, increased central venous pressure and dyspnoea initiated in less than 24 hours and up to 4 days after the end of the infusion of the total cyclophosphamide dose (200mg / kg) of the transplant. In three of five patients investigated by echocardiography, alterations suggestive of cardiac dysfunction were detected, corroborating the clinical findings of cardiac dysfunction. One patient evolved with refractory shock and subsequent death due to multiple organ failure. One patient required pericardiocentesis due to cardiac tamponade and, in the others, management with medications reversed the clinical alterations. Serum natriuretic peptide levels were higher (p<0,0005) in the patients with than in the patients without any signs of cardiac toxicity. Clinical evaluations by the nursing staff allowed the detection of cardiac dysfunctions after infusion of high dose cyclophosphamide, retrospectively confirmed by elevation of serum levels of natriuretic peptide. The reduced number of participants did not allow for statistical analyzes to predict cardiotoxicity and was a limitation of the study. In the future, we aim to increase the number of patients in the study and to identify predictive markers of cardiotoxicity before and during transplant procedure
214

Apports de l' analyse et l'intégration de données génomiques pour l'étude de la transcription et des réseaux de régulation dans le système hématopoïétique / Analysis and integration of genomic data for the study of transcription and regulation networks in the hematopoietic system

Lepoivre, Cyrille 14 November 2012 (has links)
Un des défis fondamentaux de la biologie moderne est une meilleure compréhension des mécanismes de régulation de l'expression des gènes, dont dépendent notamment le fonctionnement et la différentiation des cellules. En outre, leurs dérèglements peuvent être à l'origine de pathologies comme par exemple les cancers. Les technologies haut-débit de l'ère post-génomique permettent la production massive de données concernant notamment l'expression des gènes, les sites de fixation des facteurs de transcription et l'état de la chromatine. Ces données sont une mine d'informations pour l'étude des mécanismes de régulation. Cependant, la quantité et l'hétérogénéité de ces données soulèvent de nombreuses problématiques bioinformatiques liées à l'accès, la visualisation, l'analyse et l'intégration de celles-ci.Cette thèse aborde un certain nombre de ces aspects, à travers plusieurs projets :- la caractérisation bioinformatique de transcrits anti-sens produits par des promoteurs bidirectionnels durant le développement thymocytaire- le développement et l'intégration d'un compendium d'interactions géniques de natures diverses (interactions physiques, régulations, etc), ainsi qu'un outil de visualisation de graphes adapté - l'étude d'un système de transdifférentiation de lymphocytes pre-B en macrophages par induction de CEBPa, et la construction d'un modèle de régulation, grâce à l'analyse intégrée de données de puces à ADN, de ChIP-seq et de séquence / One of the fundamental challenges of modern biology is to better understand the mechanisms regulating gene expression, on which the functioning and differentiation of cells depend. In particular, disorders in these mechanisms may be the cause of diseases such as cancer. High throughput technologies of the post-genomic era allow mass production of data including gene expression, binding sites of transcription factors and chromatin state. These data a wealth of information for the study of regulatory mechanisms. However, the amount and heterogeneity of these data raise many bioinformatics issues related to access, visualization, analysis and integration of these.This thesis addresses a number of these aspects, through several projects:- bioinformatics characterization of antisense transcripts produced by bidirectional promoters during thymocyte development,- development and integration of a compendium of gene interactions of various kinds (physical interactions, regulations, etc.), and a graph visualization tool,- the study of a transdifferentiation system of pre-B lymphocytes into macrophages by induction of CEBPa, and the construction of a regulation model, thanks to the integrated analysis of DNA microarrays, ChIP-seq and sequence data.This work provides an illustration of some of the bioinformatics issues related to the exploitation of these data and methodologies to efficiently extract biological information, particularly to answer questions regarding the mechanisms of transcription and its regulation in the hematopoietic system.
215

Towards the identification of cellular and molecular regulators of hematopoietic stem cell self-renewal

Faubert, Amélie. January 2007 (has links)
No description available.
216

Ex vivo expansion of human haemopoietic progenitor cells

Haylock, David Norman. January 2001 (has links) (PDF)
"December 2001." Includes bibliographical references (leaves 178-225) Focuses on the ex vivo growth of human haemopoietic progenitor cells with the objective of defining culture conditions for generating myeloid post-progenitor cells for therapy
217

Structure-junction studies on human granulocyte-macrophage colony-stimulating factor / Timothy Robert Hercus.

Hercus, Timothy Robert January 1994 (has links)
Copies of author's previously published articles inserted. / Includes bibliographical references. / vi, 135, [109] leaves, [23] leaves of plates : ill. (some col.) ; 30 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / Studies the structure-function properties of the human cytokine, granulocyte-macrophage colony-stimulating factor (GM-CSF) in order to generate molecules with novel biological properties. / Thesis (Ph.D.)--University of Adelaide, Dept. of Microbiology and Immunology, 1995
218

Ex vivo expansion of human haemopoietic progenitor cells / by David Norman Haylock.

Haylock, David Norman January 2001 (has links)
"December 2001." / Includes bibliographical references (leaves 178-225) / xviii, 225 leaves : ill. (some col.), plates, charts ; 30 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / Focuses on the ex vivo growth of human haemopoietic progenitor cells with the objective of defining culture conditions for generating myeloid post-progenitor cells for therapy / Thesis (Ph.D.)--University of Adelaide, Dept. of Molecular Biosciences, 2001
219

White Spot Syndrome Virus Interaction with a Freshwater Crayfish

Jiravanichpaisal, Pikul January 2005 (has links)
Viruses are very abundant in water and hence diseases caused by viruses are common in marine organisms. These diseases create great problems for the commercial farming of crustaceans and mussels. One of the most common and most disastrous diseases for shrimp is caused by the white spot syndrome virus (WSSV), which is spread all around the world and also is infecting many different species of crustaceans including freshwater crayfish. Although during recent years knowledge has been gathered on the ways in which invertebrates defend themselves against bacteria and fungi virtually nothing is known about the defence processes elicited by virus. The aim of this work was to develop a model to use for studies of virus-host interactions in vivo and in vitro. Temperature was found to be important for the virus infectivity and at lower temperature the virus apparently did not replicate, but if animals kept at low temperature for more than 40 days were transferred to higher temperatures they died quickly due to an increased virus replication. In crayfish infected with the virus it was found that hemocytes did not degranulate and the melanization reaction was also inhibited in the hemocyes. Thus it is apparent that this virus interacts with the immune system and hemocytes in particular and to be able to study this in some greater detail it was necessary to develop a cell culture to study virus-host interactions at the molecular level. Hence, we have developed a stem cell culture from the hematopoietic tissue (hpt) that will differentiate and mature into hemocytes and which can be used to replicate the WSSV in the presence of an endogenous cytokine, astakine. Astakine is the first cytokine like-factor described which is directly involved in hematopoiesis in an invertebrate.
220

Receptor tyrosine kinase c-Kit signalling in hematopoietic progenitor cells

Edling, Charlotte January 2006 (has links)
The receptor tyrosine kinase (RTK) c-Kit is expressed in hematopoietic stem and progenitor cells, mast cells and in several non-hematopoietic tissues. In the hematopoietic system c-Kit and its ligand Steel Factor (SF, aka Stem Cell Factor) are critical for proliferation, survival and differentiation. Mutations in either receptor or ligand lead to lethal anaemia, hematopoietic stem cell defects, mast cell deficiency and a series of non-hematological defects. The aims of the studies included in this thesis are to describe the signalling pathways downstream c-Kit in hematopoietic stem/progenitor cells and to further analyse the role of c-Kit signalling in fundamental biological functions. To study c-Kit signalling in the hematopoietic system we have employed hematopoietic stem cell-like cell lines which share many properties with primary hematopoietic stem cells in vitro and in vivo, including surface markers, multipotentiality, capacity for self-renewal and long term repopulation. In paper I we demonstrate that upon SF activation the RTK c-Kit is autophosphorylated and downstream signalling mediators are transiently activated. Surprisingly we find that the c-Kit mediated activation of the MAPK pathway is dependent on the activation of phosphoinositide 3-kinase (PI3K) in hematopoietic progenitor cells and that differentiation of these progenitors to mast cells results in a signalling switch where Raf activation changes from PI3K dependent to PI3K independent. We here establish that PI3K activity is required for viability and proliferation of hematopoietic progenitor cells. In paper II we studied the conventional protein kinase C (cPKC) involvement in c-Kit signalling. We observe that the cPKCs can phosphorylate c-Kit on serine 746 and that this phosphorylation negatively regulates the activation of the receptor. We demonstrate that inhibition of this negative phosphorylation results in dramatically increased protein kinase B (PKB) activation and as a consequence inhibition of cPKCs rescues cells from starvation induced apoptosis. Moreover we exhibit that the cPKCs are necessary for full activation of extracellular signal-regulated kinase (Erk) and that impaired PKC activity leads to hampered proliferation. In paper III we demonstrate that in addition to the cPKCs also the novel PKC is required for Erk activation and proliferation. Furthermore we present results indicating that PKC negatively regulates differentiation of bone marrow. In conclusion, with the studies in this thesis we display details in the signalling pathways induced upon RTK c-Kit activation and we demonstrate that c-Kit has significant effects on hematopoietic cell-physiology.

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