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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.
21

OntoStudyEdit

Uciteli, Alexandr, Herre, Heinrich 10 February 2016 (has links) (PDF)
Background: The specification of metadata in clinical and epidemiological study projects absorbs significant expense. The validity and quality of the collected data depend heavily on the precise and semantical correct representation of their metadata. In various research organizations, which are planning and coordinating studies, the required metadata are specified differently, depending on many conditions, e.g., on the used study management software. The latter does not always meet the needs of a particular research organization, e.g., with respect to the relevant metadata attributes and structuring possibilities. Methods: The objective of the research, set forth in this paper, is the development of a new approach for ontology-based representation and management of metadata. The basic features of this approach are demonstrated by the software tool OntoStudyEdit (OSE). The OSE is designed and developed according to the three ontology method. This method for developing software is based on the interactions of three different kinds of ontologies: a task ontology, a domain ontology and a top-level ontology. Results: The OSE can be easily adapted to different requirements, and it supports an ontologically founded representation and efficient management of metadata. The metadata specifications can by imported from various sources; they can be edited with the OSE, and they can be exported in/to several formats, which are used, e.g., by different study management software. Conclusions: Advantages of this approach are the adaptability of the OSE by integrating suitable domain ontologies, the ontological specification of mappings between the import/export formats and the DO, the specification of the study metadata in a uniform manner and its reuse in different research projects, and an intuitive data entry for non-expert users.
22

EGFR and HER2 Targeting for Radionuclide-Based Imaging and Therapy : Preclinical Studies

Nordberg, Erika January 2008 (has links)
<p>The optimal way to detect and treat cancer is to target cancer cells exclusively without affecting the surrounding tissue. One promising approach is to use radiolabelled molecules to target receptors that are overexpressed in cancer cells. Since the epidermal growth factor receptor (EGFR) family is overexpressed in many types of cancer, it is an attractive target for both diagnostic and therapeutic applications.</p><p>This thesis can be divided into two parts. In part one (paper I), studies were conducted to modulate radionuclide uptake in tumour cells. The results showed that it was possible to modulate the cellular uptake of <sup>125</sup>I delivered by trastuzumab (targeting HER2) by adding EGF (targeting EGFR).</p><p>In part two (papers II-V) a high affinity EGFR-targeting affibody molecule (Z<sub>EGFR:955</sub>)<sub>2</sub> was selected and analysed both <i>in vitro</i> and <i>in vivo</i>. In papers II, III and V, the results obtained when using (Z<sub>EGFR:955</sub>)<sub>2</sub> were compared with those obtained with the two EGFR-binding molecules, EGF and cetuximab. These studies demonstrated that the affibody molecule bound specifically to EGFR (probably to subdomain III) with high affinity (~50 nM in biosensor analysis and ~1 nM in cellular studies) and produced intracellular signalling changes similar to those with cetuximab. In paper IV, <i>in vivo</i> studies were made, demonstrating that [<sup>111</sup>In](Z<sub>EGFR:955</sub>)<sub>2</sub> gave a tumour-specific <sup>111</sup>In uptake of 3.8±1.4% of injected dose per gram tumour tissue, 4 h post-injection. The tumours could be easily visualized with a gamma camera at this time-point. </p><p>The results of these studies indicated that the affibody molecule (Z<sub>EGFR:955</sub>)<sub>2</sub> is a possible candidate for radionuclide-based imaging of EGFR-expressing tumours. The biological effects of (Z<sub>EGFR:955</sub>)<sub>2</sub> might be of interest for therapy applications.</p>
23

Synthesis of functional nanomaterials by femtosecond laser ablation in liquids / Synthèse de nanomatériaux fonctionnels par ablation laser femtoseconde dans des liquides

Popov, Anton 21 January 2019 (has links)
Cette thèse visait à développer des techniques d'ablation au laser et de fragmentation dans des liquides pour la synthèse de nouveaux NPs ayant des fonctionnalités utiles. L’approche de la thèse est axée sur l’élaboration de la technique ablative au laser pour la synthèse de matériaux conventionnels avec des paramètres pour des applications biomédicales sélectionnées, ainsi que sur le développement de cette technique pour la synthèse de nouveaux nanomatériaux destinés à des applications biomédicales. En particulier, il comprend:1. Nous avons élaboré un régime de fragmentation laser fs à partir de colloïdes de Si pour la synthèse de NPs de Si ayant une taille, une cristallinité et un état d'oxydation contrôlables.Nous avons testé un certain nombre d’applications biomédiales particulières de Si Si préparés de cette manière.2. Nous avons développé une technique d'ablation et de fragmentation au laser fs pour fabriquer des noyaux Au NPs et des carottes en Au-Si nus pour SERSapplications. Une approche est basée sur l'ablation au laser de la cible Au dans une solution colloïdale de NP Si.3. Pour la première fois, nous avons synthétisé de nouveaux NP plasmoniques à base de nitrure de titane. Nous avons également montré qu’une étape supplémentaire de fragmentation du laser fs entraînait une diminution de la taille des NP à 5 nm. En outre, nous avons constaté que ces NP ont un très large pic d'extinction dans le proche IR.4. Pour la première fois, nous avons démontré la synthèse de NPs organiques fluorescentes d'un luminophore à émission induite par agrégation spécialement conçu (AIE LP). La luminosité de ces NP a été jugée comparable à celle des points quantiques. / This thesis as aimed at the development of techniques of fs laser ablation and fragmentation in liquids for the synthesis of novel NPs having useful functionalities. The approach of the thesis is focused on the elaboration of the laser ablative technique for the synthesis of conventional materials with parameters for selected biomedical applications, as well as the development of this technique for the synthesis of novel nanomaterials for biomedical applications. In particular it includes:1. We elaborated a regime of fs laser fragmentation from Si colloids for the synthesis of Si NPs having controllable size, crystallinity and oxidation state. We tested so-prepared Si NPs a number of particular biomedial applications.2. We elaborated a technique of fs laser ablation and fragmentation to fabricate bare Au NPs and Au-Si core-shells for SERSapplications. One approache is based on laser ablation of Au target in colloidal solution of Si NPs. 3. For the first time we synthesized novel plasmonic NPs based on titanium nitride. We also showed that an additional fs laser fragmentation step leads to the decrease of NPs size to 5 nm. Besides, we found that such NPs have a very broad extinction peak in the near IR.4. For the first time we demonstrated the synthesis of fluorescent organic NPs of specially designed aggregation-induced emission luminophore (AIE LP). The brightness of such NPs was determined to be comparable to that of quantum dots.
24

Cationic polymer brush coated nanoparticles for gene delivery

Li, Danyang January 2018 (has links)
Polymer brushes generated via "grafting-from" approach emerged as an attractive surface modification tool offering chemical stability, synthetic flexibility and unprecedented control over the polymer grafting density, thickness, chemical composition and functionality. They display interesting features to many applications in regenerative medicine including cell culture, tissue engineering and as delivery systems due to exquisite control of physicochemical and biological properties. Cationic polymer brushes are particularly attractive in the field of designing effective vectors for gene delivery as polymer brush allows the design and coating of a variety of particles with well-defined core-shell architecture and chemistry to efficiently condense and deliver nucleic acids. This thesis concentrates on designing safe and efficient gene delivery vectors based on 'graft from' cationic polymer brush and understanding the interaction of nucleic acids with polymer brush. Chapter one presented fundamental knowledge of polymer brush and its biomedical application. The first part of this chapter describes the definition of polymer brush, the preparation strategies, mechanism of atom transfer radical polymerisation and the responsiveness of polymer brush including solvent, pH and ionic strength. The second part discusses the state-of-art applications of polymer brush in regenerative medicine including protein resistant polymer brush for tissue engineering and as drug/gene delivery systems.
25

Tumor Cell Targeting of Stabilized Liposome Conjugates : Experimental studies using boronated DNA-binding agents

Bohl Kullberg, Erika January 2003 (has links)
<p>To further develop cancer therapy, targeted delivery of cell killing agents directly to tumor cells is an interesting approach. This thesis describes the development of PEG-stabilized liposome conjugates targeting either epidermal growth factor receptor (EGFR) using its natural ligand EGF, or human epidermal growth factor receptor 2 (HER-2) using the antibody trastuzumab. Both receptors are known to be overexpressed on a variety of tumors. The liposomes were loaded with the boronated compounds water soluble boronated acridine (WSA) or water soluble boronated phenantridine (WSP), compounds primarily developed for boron neutron capture therapy, BNCT. </p><p>The liposome conjugates bound specifically to their receptors in cell culture. Because the WSA conjugates exhibited the most favorable boron uptake this compound was chosen for further study. The WSA-loaded liposome conjugates was internalized, an important characteristic for BNCT, and had a long retention inside the cells. The cellular localization of WSA, studied using fluorescence was found to be mainly cytoplasmic. </p><p>To increase the boron uptake studies comparing different incubation methods was performed. It was shown for both EGF and trastuzumab targeted liposomes the uptake could be increased over 10 times by changing from incubation in monolayer culture to incubation in cell suspension in roller flasks. With this treatment the boron concentrations reached after 24 h incubation time was 90 ppm for EGF-liposomes and 132 ppm for trastuzumab-liposomes, levels that are clinically interesting. </p><p>To study the cell-killing efficacy of the liposome-conjugates an experimental BNCT study was performed using EGF-liposome-WSA on cultured glioma cells. About half the number of thermal neutron was needed to inactivate 90% of the cells if the cells had been incubated with EGF-liposome-WSA compared to control cells. When comparing the survival to dose it was shown that to inactivate 90% of the cells 2.9 Gy was needed for EGF-liposome-WSA and neutrons compared to 5.6 Gy with <sup>137</sup>Cs gamma. </p><p>The biodistribution of EGF-liposomes was also studied in mice. It was compared to EGF and it was found that the addition of a PEG-stabilized liposome to EGF significantly reduced EGF uptake in liver and kidneys, the circulation time in blood was prolonged as well. The reduced liver uptake might be due to inability of the 100 nm liposomes to pass the sinusoidal fenestrations of the liver and bind to the EGFR-rich hepatocytes. The reduced liver uptake potentates the use of EGF-liposome conjugates for systemic injection.</p>
26

Tumor Cell Targeting of Stabilized Liposome Conjugates : Experimental studies using boronated DNA-binding agents

Bohl Kullberg, Erika January 2003 (has links)
To further develop cancer therapy, targeted delivery of cell killing agents directly to tumor cells is an interesting approach. This thesis describes the development of PEG-stabilized liposome conjugates targeting either epidermal growth factor receptor (EGFR) using its natural ligand EGF, or human epidermal growth factor receptor 2 (HER-2) using the antibody trastuzumab. Both receptors are known to be overexpressed on a variety of tumors. The liposomes were loaded with the boronated compounds water soluble boronated acridine (WSA) or water soluble boronated phenantridine (WSP), compounds primarily developed for boron neutron capture therapy, BNCT. The liposome conjugates bound specifically to their receptors in cell culture. Because the WSA conjugates exhibited the most favorable boron uptake this compound was chosen for further study. The WSA-loaded liposome conjugates was internalized, an important characteristic for BNCT, and had a long retention inside the cells. The cellular localization of WSA, studied using fluorescence was found to be mainly cytoplasmic. To increase the boron uptake studies comparing different incubation methods was performed. It was shown for both EGF and trastuzumab targeted liposomes the uptake could be increased over 10 times by changing from incubation in monolayer culture to incubation in cell suspension in roller flasks. With this treatment the boron concentrations reached after 24 h incubation time was 90 ppm for EGF-liposomes and 132 ppm for trastuzumab-liposomes, levels that are clinically interesting. To study the cell-killing efficacy of the liposome-conjugates an experimental BNCT study was performed using EGF-liposome-WSA on cultured glioma cells. About half the number of thermal neutron was needed to inactivate 90% of the cells if the cells had been incubated with EGF-liposome-WSA compared to control cells. When comparing the survival to dose it was shown that to inactivate 90% of the cells 2.9 Gy was needed for EGF-liposome-WSA and neutrons compared to 5.6 Gy with 137Cs gamma. The biodistribution of EGF-liposomes was also studied in mice. It was compared to EGF and it was found that the addition of a PEG-stabilized liposome to EGF significantly reduced EGF uptake in liver and kidneys, the circulation time in blood was prolonged as well. The reduced liver uptake might be due to inability of the 100 nm liposomes to pass the sinusoidal fenestrations of the liver and bind to the EGFR-rich hepatocytes. The reduced liver uptake potentates the use of EGF-liposome conjugates for systemic injection.
27

Towards a New Hospital: Architecture, Medicine, and Computation, 1960-75

Theodore, David Michael January 2014 (has links)
This dissertation provides an account of how computing left behind its origins in academic and military research to become part of the hospital's equipmental setting. I examine the efforts of reformers, including administrators, planners, architects, and computer consultants, to provide appropriate accommodation for modern biomedicine. I explore three stories in order to untangle the admixture of architecture, medicine, and computation as they intertwined through a mutual engagement with automation, operations research, cybernetics, and biomedical research in the postwar hospital. In Boston, pioneering research consultants Bolt Beranek and Newman collaborated with the Massachusetts General Hospital on an experimental total information system known as the Hospital Computer Project. In London, architects Llewelyn Davies Weeks used computer algorithms to help design Northwick Park Hospital. And in Canada, the Montreal Neurological Institute adopted computing to transform its expertise in clinical brain imaging research. When possible, I emphasize specific computers, arguing that attention to the presence of the machine itself contributes to our understanding of hospital life.
28

Biomedicininės informacinės sistemos realizacija internete / Realization of Informational System in the Field of Biomedicine

Dieninis, Žydrūnas 22 September 2004 (has links)
The business of healthcare management is changing rapidly, heading in the direction of managed care, capitation, and integrated delivery systems. Information management is crucial to the success and competitiveness of these new care delivery systems. A major goal of this work is to develop a model for a computer-based patient medical record system which could be accessed through the world wide web. The fundamental function of such system is to record, monitor, retrieve all events associated with an encounter between the patient and the healthcare system. This document presents a description of informational system in the field of biomedicine which is appointed to patients, with coronary heart disease. First of all, urgency, applicability and functions of such informative system are presented. Further the main points of the problem, which consists of system realization and publishing on the web, and its solutions are analyzed in details.
29

EGFR and HER2 Targeting for Radionuclide-Based Imaging and Therapy : Preclinical Studies

Nordberg, Erika January 2008 (has links)
The optimal way to detect and treat cancer is to target cancer cells exclusively without affecting the surrounding tissue. One promising approach is to use radiolabelled molecules to target receptors that are overexpressed in cancer cells. Since the epidermal growth factor receptor (EGFR) family is overexpressed in many types of cancer, it is an attractive target for both diagnostic and therapeutic applications. This thesis can be divided into two parts. In part one (paper I), studies were conducted to modulate radionuclide uptake in tumour cells. The results showed that it was possible to modulate the cellular uptake of 125I delivered by trastuzumab (targeting HER2) by adding EGF (targeting EGFR). In part two (papers II-V) a high affinity EGFR-targeting affibody molecule (ZEGFR:955)2 was selected and analysed both in vitro and in vivo. In papers II, III and V, the results obtained when using (ZEGFR:955)2 were compared with those obtained with the two EGFR-binding molecules, EGF and cetuximab. These studies demonstrated that the affibody molecule bound specifically to EGFR (probably to subdomain III) with high affinity (~50 nM in biosensor analysis and ~1 nM in cellular studies) and produced intracellular signalling changes similar to those with cetuximab. In paper IV, in vivo studies were made, demonstrating that [111In](ZEGFR:955)2 gave a tumour-specific 111In uptake of 3.8±1.4% of injected dose per gram tumour tissue, 4 h post-injection. The tumours could be easily visualized with a gamma camera at this time-point. The results of these studies indicated that the affibody molecule (ZEGFR:955)2 is a possible candidate for radionuclide-based imaging of EGFR-expressing tumours. The biological effects of (ZEGFR:955)2 might be of interest for therapy applications.
30

Recommendations and standards for building and testing an Intensive Care Unit (ICU) electrical installation / Συστάσεις και πρότυπα για την οικοδόμηση και την δοκιμή της ηλεκτρικής εγκατάστασης στις Μονάδες Εντατικής Νοσηλείας

Χριστοδούλου, Χριστόφορος 09 January 2012 (has links)
The Intensive Care Unit, well known as ICU, is a specialized section of a hospital that provides comprehensive and continuous care (treatment and monitoring) for persons who are critically ill or in an unstable condition and who can benefit from treatment. The importance of this specific area of the hospital can be also understood from the amount and variety of the equipment that is installed inside. Therefore the Intensive Care Unit (ICU) should provide both continuous fault-free equipment operation and enhanced electrical safety for the patients and the medical staff. The main objective of the thesis is to study and design the electrical installation and the dedicated devices of a sample ICU, according to the latest European regulations and standards. In the first introductory chapter is described the main ICU medical equipment, patient modules, areas and utilities. The second chapter contains the Main Standards, Directives and Recommendations related to the building installing and testing of the ICU electrical installation and dedicated equipment. Chapter three described general the electrical safety in the ICU and the methods and means of protection against an Electrical shock. The next chapter reviews the methods and means of protection against an Equipment Malfunction and against Mains power failure. The fifth chapter is the design of a sample ICU Area including main power electrical installation and dedicated protection and monitoring devices. The last chapter includes the electrical safety tests of the installed system and dedicated devices and also the value limitations according to the European Standards and Regulations. / Η Μονάδα Εντατικής Θεραπείας, γνωστή ως ICU, είναι ένα εξειδικευμένο τμήμα του νοσοκομείου που παρέχει πλήρη και συνεχή φροντίδα (θεραπεία και παρακολούθηση) στα πρόσωπα που αντιμετωπίζουν κρίσιμα προβλήματα υγείας ή βρίσκονται σε μια ασταθή κατάσταση. Ο εξειδικευμένος εξοπλισμός της χωρίς καμία αμφιβολία μπορεί να επιφέρει πολύ θετικά αποτελέσματα στον ιατρικό τομέα Η λειτουργία και η σημασία της μονάδας, αναμφίβολα μπορούν να διαφανούν και από τον άριστο εξοπλισμό που διακατέχει. Είναι βέβαιο ότι μέσα από την συγκεκριμένη μονάδα θεραπείας μπορεί να δοθεί στον ασθενή η κατάλληλη σημασία έτσι ώστε να μπορεί να γιατρευτεί. Ο άρτια εξοπλισμός που υπάρχει μπορεί να επιφέρει άριστα αποτελέσματα. Συνεπώς, η Μονάδα Εντατικής Θεραπείας (ICU) πρέπει να συνεχίσει την απρόσκοπτη λειτουργία της και συνάμα την ενίσχυση του εξοπλισμού της, έτσι ώστε να υπάρχει ενισχυμένη ηλεκτρική ασφάλεια τόσο για τους ασθενείς όσο και για το ιατρικό προσωπικό. Ο κύριος στόχος της διατριβής είναι η μελέτη και ο σχεδιασμός της ηλεκτρικής εγκατάστασης και δείγμα των αποκλειστικών συσκευών της μονάδα, σύμφωνα με τις τελευταίες ευρωπαϊκές προδιαγραφές. Στο πρώτο εισαγωγικό κεφάλαιο, περιγράφεται ο βασικός εξοπλισμός της μονάδας και η ιατρική που παρέχεται. Ακολούθως στο δεύτερο κεφάλαιο περιλαμβάνονται οι κύριοι κανόνες, οδηγίες και οι συστάσεις που σχετίζονται με την εγκατάσταση του κτιρίου. Επίσης γίνεται αναφορά στον έλεγχο της ηλεκτρικής εγκατάστασης και του ειδικού εξοπλισμού της μονάδας. Στο τρίτο κεφάλαιο περιγράφεται η γενική ηλεκτρική ασφάλεια στη μονάδα, με ιδιαίτερη αναφορά στις μεθόδους και στα μέσα προστασίας από ηλεκτροπληξία. Στη συνέχεια στο επόμενο κεφάλαιο εξετάζεται το κατά πόσο οι μέθοδοι και τα μέσα προστασίας μπορούν να είναι λειτουργικά έναντι των δυσλειτουργιών που μπορεί να προκληθεί από την διακοπή ρεύματος. Για την όσο καλύτερη λειτουργία της μονάδας γίνεται αναφορά στο πέμπτο κεφάλαιο, όπου γίνεται νύξη για τον σχεδιασμό του χώρου της μονάδας, συμπεριλαμβανομένων των κύριων ηλεκτρικών εγκαταστάσεων συσκευών προστασίας και παρακολούθησης. Μέσα από μια εκτεταμένη ανασκόπηση, έρευνα και πληθώρα πειραμάτων στο τελευταίο κεφάλαιο παρουσιάζονται οι ηλεκτρικές δοκιμές ασφαλείας του εγκατεστημένου συστήματος, οι ειδικές συσκευές, σύμφωνα πάντα με τα Ευρωπαϊκά πρότυπα και κανονισμούς.

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