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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.
551

Outcome in psychiatric outpatient services : reliability, validity and outcome based on routine assessments with the GAF scale

Söderberg, Per, Tungström, Stefan January 2007 (has links)
The general aim of the studies presented in this thesis is to investigate the possibility of using clinical data to measure outcomes in psychiatric outpatient services. The specific aims are to investigate whether routine clinical assessments and ratings are reliable and have adequate validity, and then to use these data to calculate treatment outcomes and explore factors that affect these outcomes. The main result shows that ratings of global mental health made by clinicians in routine clinical work can be used to evaluate treatment outcomes in outpatient settings. The clinicians responsible for diagnosing and assessing patients used the GAF scale with satisfactory reliability (ICC1,1 = 0.81) and fair interrater reliability (overall kappa = 0.53) when categorizing main diagnostic groups of the DSM-IV axis I. The GAF scale can thus be used to assess global mental health and to monitor outcomes in clinical settings. However, a GAF culture bias was observed. This bias can probably be corrected with feedback and training. Psychiatric treatment in outpatient settings had a generally positive effect on patients’ global mental heath (ES = 0.65). The overall result when clinical significance methodology was used showed that 28.1% of the patients had recovered and a further 6.6% showed reliable improvement. Patients being treated with psychotherapeutically influenced methods showed a considerably better effect (ES = 1.00). There is a dose of sessions effect that is particularly marked for short treatment episodes. Thirteen sessions are required for 50% of the patients to show reliable improvement. The strongest influence on treatment outcome was whether the termination of a patient’s treatment was planned or unplanned. In conclusion: Clinical databases can be used to study the outcome of psychiatric services provided they a) include a large number of subjects representing an intention-to-treat perspective; b) the instruments used are clinically relevant and reliable; c) the raters contributing to the data base are motivated to decrease attrition; d) the database includes extensive data to allow for control of confounding factors; and e) data are collected at critical occasions in treatment, such as at the start of treatment and at discharge from treatment, making it possible to focus on effects. Psychiatric outpatient treatment has a positive effect, but considerable improvements may be possible with more stringent use of psychotherapeutic methods, sufficient doses of sessions, and planned terminations. However, the progress of treatment is also affected by such factors as pre-treatment severity and diagnoses.
552

The role of the Type IV pili system in the virulence of Francisella tularensis

Salomonsson, Emelie January 2008 (has links)
Francisella tularensis is a Gram-negative intracellular pathogen causing the zoonotic disease tularemia. F. tularensis can be found almost all over the world and has been recovered from several animal species, even though the natural reservoir of the bacterium and parts of its life cycle are still unknown. Humans usually get infected after handling infected animals or from bites of blood-feeding arthropod vectors. There are four subspecies of F. tularensis: the highly virulent tularensis (Type A) that causes a very aggressive form of the disease, with mortality as high as 60% if untreated, the moderately virulent holarctica (Type B) and mediasiatica, and the essentially avirulent subspecies F. novicida. So far, our knowledge of the molecular mechanisms that would explain these differences in virulence among the subspecies is poor. However, recent developments of genetic tools and access to genomic sequences have laid the ground for progress in this research field. Analysis of genome sequences have identified several regions that differ between F. tularensis subspecies. One of these regions, RD19, encodes proteins postulated to be involved in assembly of type IV pili (Tfp), organelles that have been implicated in processes like twitching motility, biofilm formation and cell-to-cell communication in pathogenic bacteria. While there have been reports of pili-like structures on the surface of F. tularensis, these have not been linked to the Tfp encoding gene clusters until now. Herein, I present evidence that the Francisella pilin, PilA, can complement pilin-like characteristics and promote assembly of fibers in a heterologous system in Neisseria gonorrhoeae. pilA was demonstrated to be required for full virulence of both type A and type B strains in mice when infected via peripheral routes. A second region, RD18, encoding a protein unique to F. tularensis and without any known function, was verified to be essential for virulence in a type A strain. Interestingly, the non-licensed live vaccine strain, LVS (Type B), lacks both RD18 and RD19 (pilA) due to deletion events mediated by flanking direct repeats. The loss of RD18 and RD19 is responsible for the attenuation of LVS, since re-introducing them in cis could restore the virulence to a level similar to a virulent type B strain. Significantly, these deletion events are irreversible, preventing LVS to revert to a more virulent form. Therefore, this important finding could facilitate the licensing of LVS as a vaccine against tularemia.
553

Lifestyle and Genome Evolution in Vector-Borne Bacteria : A Comparison of Three Bartonella Species / Livsstil och genomevolution i vektorburna bakterier : en jämförelse av tre Bartonella-arter

Frank, Anna Carolin January 2005 (has links)
Bacterial genomes provide records of the molecular processes associated with emergence and evolution of different bacterial lifestyles. This thesis is based on whole-genome comparisons within the genus Bartonella, an excellent model system for studies of host- and vector-specificity and infection outcome in animal-associated bacteria. The louse-borne human specialist and trench fever agent Bartonella quintana was contrasted to the flea-borne generalist relatives Bartonella henselae and Bartonella grahamii, which cause asymptomatic infection in cat and mouse respectively. While B. henselae is commonly isolated from humans, and causes cat scratch disease, there is only one reported case of B. grahamii human infection. The gene complements of the three species are nested like Russian dolls with the smaller genome (B. quintana) being entirely contained in the medium sized (B. henselae), which in turned is contained in the largest (B. grahamii). Size differences reflect differences in the horizontally and vertically acquired gene content, and in the number of genus- and species- specific genes, owing to differential impact of bacteriophages and plasmids, and to different degrees of genome decay. These processes can be attributed to the three distinct lifestyles. Comparisons with other alpha-proteobacteria suggest that the Bartonella genus as a whole evolved from plant-associated species, and that horizontal transfer, in particular of genes involved in interaction with the host, played a key role in the transition to animal intracellular lifestyle. The long-term genome decay associated with this lifestyle is most advanced in the host-restricted B. quintana. The broad host-range species B. grahamii has the largest genome and the largest proportion of auxiliary DNA of the three, probably because it has access to a larger gene pool. In encodes all the known pathogenicity determinants found in the genomes of B. henselae and B. quintana, suggesting that these genes primarily evolved to facilitate colonization in the reservoir host.
554

Basement membrane collagens in pancreatic cancer : novel stroma-derived tumor markers and regulators of cancer cell growth / Basalmembranskollagener vid pankreascancer : utgör nya stromala tumörmarkörer och reglerar cancercellstillväxt

Öhlund, Daniel January 2010 (has links)
Background: Among the common malignancies, pancreatic cancer has the shortest long-term survival. The aggressive, rapid, and infiltrative growth pattern of pancreatic cancer, together with the lack of specific symptoms, often leads to late diagnosis. Metastases are frequently found at the time of diagnosis, which prevents curative surgical treatment. Good tumor markers would enable early detection, thus improving the prognosis. Unfortunately, no such markers are available in the clinic. The tumor stroma is defined as the non-malignant cells and the extracellular matrix (ECM) of a cancer. Pancreatic cancer is characterized by an abundant tumor stroma, rich in ECM proteins such as collagens, which have been shown to play important roles in tumor progression. Furthermore, pancreatic cancer cells produce large quantities of ECM proteins, especially the basement membrane (BM) protein type IV collagen. All epithelial cells are anchored to a BM, which must be degraded in order for an in situ cancer to become invasive. Matrix metalloproteinases (MMPs) are enzymes involved in BM degradation. In this thesis, the tumor stroma of pancreatic cancer is studied, focusing on the BM proteins type IV and type XVIII collagen, with the aim to clarify if the stroma could be a source of novel tumor markers for this form of cancer. Additionally, the role of type IV collagen produced by the cancer cells is studied. Methods: Expression patterns of type IV and type XVIII collagen, MMPs involved in collagen degradation, and collagen receptors (integrins) were studied by immunoflourescence in both normal and pancreatic cancer tissue, and in pancreatic cancer cell lines. Circulating plasma levels of type IV and type XVIII collagen and conventional tumor markers (TPS, Ca 19-9, CEA and Ca 125) were measured in controls and pancreatic cancer patients at the time of diagnosis and after treatment. The role of cancer cell produced type IV collagen was studied in human pancreatic cancer cell lines by functional blocking of integrin receptors (integrin a1, a2 and b1) and integrin-binding sites on type IV collagen, and by siRNA-induced down-regulation of type IV collagen synthesis. Proliferation was analyzed by a luminescence based cell viability assay, migration by time-lapse microscopy, and apoptosis by M30-neoepitope detection. Results: MMPs involved in BM degradation were upregulated in pancreatic cancer tissue. The expression of type XVIII collagen shifted from a general BM expression pattern in normal tissue, to mainly being found in the tumor vasculature in pancreatic cancer. Type IV collagen, on the other hand, remained highly expressed in the vicinity of the cancer cells. The a1, a2, and b1 integrin receptors were highly expressed at the cancer cell surface. Both down-regulation of type IV collagen synthesis and blocking the integrin/type IV collagen interaction decreased cell proliferation and migration. The proliferative capacity was rescued by the addition of exogenous type IV collagen. Furthermore, the circulating levels of both type IV and type XVIII collagen were increased in pancreatic cancer patients at the time of diagnosis compared to controls. After treatment, the levels were normalized for type XVIII collagen, whereas the levels of type IV collagen remained high after surgery. High postoperative levels of type IV collagen were associated with short overall survival. A similar association to short survival was found for preoperative type XVIII collagen levels. No such associations to survival could be detected for the conventional markers.   Conclusion: The results of this thesis show that type IV and type XVIII collagens can serve as tumor markers for pancreatic cancer with advantages compared to conventionally used markers. Additionally, evidence is provided of an autocrine loop, involving type IV collagen and its integrin receptors, with importance for retaining a proliferative and migratory phenotype in pancreatic cancer cells.
555

Agoraphobia and Panic

Wittchen, Hans-Ulrich, Nocon, Agnes, Beesdo, Katja, Pine, Daniel S., Höfler, Michael, Lieb, Roselind, Gloster, Andrew T. 29 November 2012 (has links) (PDF)
Background: The relationship of panic attacks (PA), panic disorder (PD) and agoraphobia (AG) is controversial. The aim of the current study is to prospectively examine the 10-year natural course of PA, PD and AG in the first three decades of life, their stability and their reciprocal transitions. Methods: DSM-IV syndromes were assessed via Composite International Diagnostic Interview – Munich version in a 10-year prospective-longitudinal community study of 3,021 subjects aged 14–24 years at baseline. Results: (1) Incidence patterns for PA (9.4%), PD (with and without AG: 3.4%) and AG (5.3%) revealed differences in age of onset, incidence risk and gender differentiation. (2) Temporally primary PA and PD revealed only a moderately increased risk for subsequent onset of AG, and primary AG had an even lower risk for subsequent PA and PD. (3) In strictly prospective analyses, all baseline groups (PA, PD, AG) had low remission rates (0–23%). Baseline PD with AG or AG with PA were more likely to have follow-up AG, PA and other anxiety disorders and more frequent complications (impairment, disability, help-seeking, comorbidity) as compared to PD without AG and AG without PA. Conclusions: Differences in incidence patterns, syndrome progression and outcome, and syndrome stability over time indicate that AG exists as a clinically significant phobic condition independent of PD. The majority of agoraphobic subjects in this community sample never experienced PA, calling into question the current pathogenic assumptions underlying the classification of AG as merely a consequence of panic. The findings point to the necessity of rethinking diagnostic concepts and DSM diagnostic hierarchies.
556

Study on linking a SuperCritical water-cooled nuclear reactor to a hydrogen production facility

Lukomski, Andrew John 01 July 2011 (has links)
The SuperCritical Water-cooled nuclear Reactor (SCWR) is one of six Generation-IV nuclear-reactor concepts currently being designed. It will operate at pressures of 25 MPa and temperatures up to 625°C. These operating conditions make a SuperCritical Water (SCW) Nuclear Power Plant (NPP) suitable to support thermochemical-based hydrogen production via co-generation. The Copper-Chlorine (Cu‒Cl) cycle is a prospective thermochemical cycle with a maximum temperature requirement of ~530°C and could be linked to an SCW NPP through a piping network. An intermediate Heat eXchanger (HX) is considered as a medium for heat transfer with operating fluids selected to be SCW and SuperHeated Steam (SHS). Thermalhydraulic calculations based on an iterative energy balance procedure are performed for counter-flow double-pipe design concept HXs integrated at several locations on an SCW NPP coolant loop. Using various test cases, design and operating parameters are recommended for detailed future research. In addition, predicted effects of heat transfer enhancement on HX parameters are evaluated considering theoretical improvements from helically-corrugated HX piping. The effects of operating fluid pressure drop are briefly discussed for applicability in future studies. / UOIT
557

Diversity of Pseudomonas aeruginosa Type IV Pilins and Identification of a Novel D-arabinofuranose Post-translational Modification

Kus, Julianne 31 July 2008 (has links)
The opportunistic bacterial pathogen Pseudomonas aeruginosa uses type IV pili (T4P) for adherence to, and rapid colonization of, surfaces via twitching motility. T4P are formed from thousands of pilin (PilA) subunits. Two groups of P. aeruginosa pilins were described previously (I and II), distinguished by protein length and sequence. PilA_I was glycosylated with an O-antigen subunit through the action of PilO/TfpO, encoded downstream of pilA_I. To determine if additional pilin variants existed, analysis of the pilin locus of >300 P. aeruginosa strains from a variety of environments was conducted. Three additional pilin alleles were discovered, each of which was invariantly associated with a unique, previously unidentified, downstream gene(s): pilA_III+tfpY, pilAIV+tfpW+tfpX, pilA_V+tfpZ. This survey also revealed that strains with group I T4P were more commonly associated with respiratory infections than strains with other pilins, suggesting that glycosylated T4P may confer a colonization advantage in this environment. The newly identified group IV pilin, represented by strain Pa5196, migrated aberrantly through SDS-PA gels, suggesting it was also glycosylated, a hypothesis confirmed by periodic acid-Schiff staining and mass spectrometry (MS) analyses. Disruption of Pa5196 O-antigen biosynthesis did not prevent the production of glycosylated pilins, demonstrating that these pilins were modified in a novel manner, unlike group I pilins. Using MS, nuclear magnetic resonance spectroscopy and site-directed mutagenesis, the Pa5196 pilins were shown to be uniquely modified with homo-oligosaccharides of mycobacterial-like α-1,5-D-arabinofuranose at multiple locations. Residues Thr64 and Thr66, located on the αβ-loop region of the protein, appear to be the preferred, but not exclusive sites of modification, each being modified with up to four D-Araf sugars. This region of the pilin is partially surface-exposed in the pilus, therefore modification of these sites may influence the surface chemistry of the fibre. Residues Ser81, Ser82, Ser85 and Ser89, located in the β-strand region, were also modified, mainly with mono- and disaccharides. Bioinformatic analyses and mutagenesis of TfpW suggest that this novel protein is an arabinosyltransferase necessary for PilA_IV modification. This research has increased our understanding of the complexity of this virulence factor, and may aid in development of new therapeutics for P. aeruginosa and mycobacterial infections.
558

The present and future of clinical psychology in Germany

Hoyer, Jürgen, Wittchen, Hans-Ulrich 22 January 2013 (has links) (PDF)
Introduction: This paper does not aim to predict the future of clinical psychology in Germany. The future of psychology depends on the complex interaction between political, sociological, economic and health-care related factors as well as on the scientific progress in the discipline itself and in neighbour disciplines. However, it is fair to say that clinical psychology continues to gain even stronger influences in health care and will face a number of new challenges over the next years of its expansion. Our paper will present some of these potential fields of development and change based on a brief description of the status quo. The focus of the article will be specific developments in Germany, although there will be an overlap with general tendencies that describe the situation of clinical psychology in the new millenium in general. Furthermore, for research as well as practice, the specific relationship between clinical psychology and psyciatry will be highlighted.
559

Diversity of Pseudomonas aeruginosa Type IV Pilins and Identification of a Novel D-arabinofuranose Post-translational Modification

Kus, Julianne 31 July 2008 (has links)
The opportunistic bacterial pathogen Pseudomonas aeruginosa uses type IV pili (T4P) for adherence to, and rapid colonization of, surfaces via twitching motility. T4P are formed from thousands of pilin (PilA) subunits. Two groups of P. aeruginosa pilins were described previously (I and II), distinguished by protein length and sequence. PilA_I was glycosylated with an O-antigen subunit through the action of PilO/TfpO, encoded downstream of pilA_I. To determine if additional pilin variants existed, analysis of the pilin locus of >300 P. aeruginosa strains from a variety of environments was conducted. Three additional pilin alleles were discovered, each of which was invariantly associated with a unique, previously unidentified, downstream gene(s): pilA_III+tfpY, pilAIV+tfpW+tfpX, pilA_V+tfpZ. This survey also revealed that strains with group I T4P were more commonly associated with respiratory infections than strains with other pilins, suggesting that glycosylated T4P may confer a colonization advantage in this environment. The newly identified group IV pilin, represented by strain Pa5196, migrated aberrantly through SDS-PA gels, suggesting it was also glycosylated, a hypothesis confirmed by periodic acid-Schiff staining and mass spectrometry (MS) analyses. Disruption of Pa5196 O-antigen biosynthesis did not prevent the production of glycosylated pilins, demonstrating that these pilins were modified in a novel manner, unlike group I pilins. Using MS, nuclear magnetic resonance spectroscopy and site-directed mutagenesis, the Pa5196 pilins were shown to be uniquely modified with homo-oligosaccharides of mycobacterial-like α-1,5-D-arabinofuranose at multiple locations. Residues Thr64 and Thr66, located on the αβ-loop region of the protein, appear to be the preferred, but not exclusive sites of modification, each being modified with up to four D-Araf sugars. This region of the pilin is partially surface-exposed in the pilus, therefore modification of these sites may influence the surface chemistry of the fibre. Residues Ser81, Ser82, Ser85 and Ser89, located in the β-strand region, were also modified, mainly with mono- and disaccharides. Bioinformatic analyses and mutagenesis of TfpW suggest that this novel protein is an arabinosyltransferase necessary for PilA_IV modification. This research has increased our understanding of the complexity of this virulence factor, and may aid in development of new therapeutics for P. aeruginosa and mycobacterial infections.
560

Nouveaux systèmes réducteurs utilisant des hydrosiloxanes comme substituts des hydrures d'aluminium et de bore : application à la réduction des fonctions amides et nitriles

Laval, Stéphane 30 September 2011 (has links) (PDF)
Ces dernières années, les recherches industrielles et académiques ont connu des bouleversements sans précédents liés à la notion de Développement Durable. Les exigences en matière de santé et d'environnement ont poussé les chimistes à concevoir des produits et procédés chimiques qui permettent de réduire ou d'éliminer les substances dangereuses. Les travaux de recherche décrits dans cette thèse s'inscrivent dans ce contexte et concernent la mise au point de nouveaux systèmes réducteurs utilisant des hydrosiloxanes comme substituts des hydrures d'aluminium et de bore. Dans cet objectif, des systèmes associant le 1,1,3,3-tétraméthyldisiloxane (TMDS) ou le polyméthylhydrosiloxane (PMHS) avec des complexes de titane ou de vanadium ont été développés pour la réduction des fonctions amides et nitriles. La nature de l'association hydrosiloxane - métal et du substrat étudié a joué un rôle important sur la performance et la sélectivité des réactions misent en oeuvre. D'une part, les réductions sélectives d'amides (tertiaires et secondaires) et de nitriles en aldéhydes ont été réalisées respectivement en présence du tétraisopropylate de titane(IV) et du triisopropylate d'oxyde de vanadium(V). D'autre part, les réductions d'amides primaires et de nitriles ont conduit aux amines primaires en présence de tétraisopropylate de titane(IV). Enfin, ces systèmes réducteurs ont été utilisés pour la synthèse d'hétérocycles azotés saturés. La réduction de composés dinitriles donne lieu à une réaction d'alkylation réductrice intramoléculaire qui conduit à la formation de dérivés de la pipéridine, de la pyrrolidine et de l'azétidine en une étape

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