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681.
682.
In this paper, we contribute with empirical insight into the complexity of establishing and sustaining integration between different information infrastructures in health care. An overall concern is to elaborate on how, despite many obstacles, the integration effort moves forward. We see this as a collective achievement, where users have an essential role in terms of mobilizing and coordinating the other actors as well as maintaining the integration. These activities are not limited to a specific project; they emerge from and are part of day-to-day practice. Empirically, we focus on a large integration initiative between the laboratory systems at the University Hospital of Northern Norway and the electronic patient records used by general practitioners in the Northern health region. Together with the vendor, Well Diagnostics, the hospital initiated a project aimed at establishing a new laboratory requisition system that enabled GPs to send requisitions electronically to the hospital laboratories. Theoretically, we draw on the concept of information infrastructures, and supplement this with Actor Network Theory. 相似文献
683.
Gunnar Peterson 《Information Security Technical Report》2010,15(4):150-153
This paper examines ways to improve security architecture by harnessing the executive attention that compliance activities like PCI DSS bring to security and focus that attention toward improving security architecture over the long term. Threat modeling fills a gap between the system's functional requirements and the auditor's checklist, and is used to catalyze this change of focus. 相似文献
684.
Dr. Alessandro Colombano Dr. Sergio Dall'Angelo Lee Kingston Gunnar Grönberg Dr. Claudia Correia Rossana Passannante Zuriñe Baz Dr. Miguel Ángel Morcillo Dr. Charles S. Elmore Dr. Jordi Llop Prof. Dr. Matteo Zanda 《ChemMedChem》2020,15(23):2317-2331
Fatty acid oxidation (FAO) produces most of the ATP used to sustain the cardiac contractile work, although glycolysis is a secondary source of ATP under normal physiological conditions. FAO impairment has been reported in the advanced stages of heart failure (HF) and is strongly linked to disease progression and severity. Thus, from a clinical perspective, FAO dysregulation provides prognostic value for HF progression, the assessment of which could be used to improve patient monitoring and the effectiveness of therapy. Positron emission tomography (PET) imaging represents a powerful tool for the assessment and quantification of metabolic pathways in vivo. Several FAO PET tracers have been reported in the literature, but none of them is in routine clinical use yet. Metabolically trapped tracers are particularly interesting because they undergo FAO to generate a radioactive metabolite that is subsequently trapped in the mitochondria, thus providing a quantitative means of measuring FAO in vivo. Herein, we describe the design, synthesis, tritium labelling and radiofluorination of 4,4,16-trifluoro-palmitate ( 1 ) as a novel potential metabolically trapped FAO tracer. Preliminary PET-CT studies on [18F] 1 in rats showed rapid blood clearance, good metabolic stability – confirmed by using [3H] 1 in vitro – and resistance towards defluorination. However, cardiac uptake in rats was modest (0.24±0.04 % ID/g), and kinetic analysis showed reversible uptake, thus indicating that [18F] 1 is not irreversibly trapped. 相似文献
685.
Henrik Lund Svend Gunnar Kaasgaard Peter Skagerlind Lene Jorgensen Christian Isak Jørgensen Marco van de Weert 《Journal of surfactants and detergents》2012,15(3):265-276
Chelators are a common ingredient in most laundry detergents. They have a number of different functions such as reducing water hardness, assisting in keeping particulate soil in suspension and the removal of certain stains, thus complementing the action of the anionic surfactants. Another important group of components in a modern liquid detergent is enzymes, mainly proteases and amylases. As the most commonly used enzymes within the detergent industry are dependent on bound calcium ions to maintain conformational stability and function, the presence of both chelators and enzymes in a liquid detergent presents a challenge. The three commonly used Ca2+ chelators: citrate, DTPA (diethylene triamine pentaacetic acid) and HEDP (1-hydroxyethane-1,1-diyl)bis(phosphonic acid), were studied with regard to their impact on protease and amylase stability in buffer and in a model liquid detergent. Enzyme stability was characterized by differential scanning calorimetry (DSC) and activity studies, and correlated to the chelator-Ca2+ interaction properties. The results show that a chelator’s ability to reduce water hardness and its Ca2+ affinity are in reality two separate aspects in the context of their use in liquid detergents. In the presence of DTPA, stoichiometric surplus of free Ca2+ is required to maintain sufficient amylase and protease stability. In the presence of the weaker chelators, HEDP and citrate, the total Ca2+ concentration is more important to protein stability than stoichiometric balancing between chelator and Ca2+. Thus, for these chelators their total concentration only has a minor impact on the Ca2+ concentration required to maintain or improve enzyme storage stability. The results underline the importance of Ca2+ in liquid detergent formulations, and suggest how proper balancing of chelators and Ca2+ can be used to improve overall enzyme stability. 相似文献
686.
Edyta Reszka Ewa Jaboska Edyta Wieczorek Peter Valent Michel Arock Gunnar Nilsson Bogusaw Nedoszytko Marek Niedoszytko 《International journal of molecular sciences》2021,22(6)
Systemic mastocytosis (SM) is a hematologic neoplasm with abnormal accumulation of mast cells in various organ systems such as the bone marrow, other visceral organs and skin. So far, only little is known about epigenetic changes contributing to the pathogenesis of SM. In the current article, we provide an overview of epigenetic changes that may occur and be relevant to mastocytosis, including mutations in genes involved in epigenetic processes, such as TET2, DNMT3A and ASXL1, and global and gene-specific methylation patterns in neoplastic cells. Moreover, we discuss methylation-specific pathways and other epigenetic events that may trigger disease progression in mast cell neoplasms. Finally, we discuss epigenetic targets and the effects of epigenetic drugs, such as demethylating agents and BET-targeting drugs, on growth and viability of neoplastic mast cells. The definitive impact of these targets and the efficacy of epigenetic therapies in advanced SM need to be explored in future preclinical studies and clinical trials. 相似文献
687.
Axel Schlitt Bernhard Schwaab Kirsten Fingscheidt Karl J. Lackner Gunnar H. Heine Alexander Vogt Michael Buerke Lars Maegdefessel Uwe Raaz Karl Werdan Xian-Cheng Jiang 《Lipids》2010,45(2):129-135
Plasma phospholipid transfer protein (PLTP) mediates both net transfer and exchange of phospholipids between different lipoproteins. Animal studies have shown that it is closely related to the development of atherosclerosis. Although many studies have indicated that PLTP activity is increased in diabetes mellitus, the role of PLTP in diabetes is still unclear. To evaluate the influence of a high-fat meal on PLTP activity, 50 nondiabetic patients with coronary heart disease (CHD), 50 insulin-treated Type 2 diabetics, and 50 healthy controls were included. We determined PLTP activity before and 4 and 8 h after a high-fat meal. As expected, serum PLTP activity was significantly higher in CHD patients than in healthy controls (71.0 ± 46.2 vs. 54.0 ± 33.8 pmol/μl/h, P = 0.032) at baseline. More importantly, we found that serum PLTP activity increased to its maximum 4 h after fat loading and then decreased to nearly basal levels after 8 h both in controls and CHD patients. In contrast, PLTP activity continuously increased during this time period in the diabetic patients. With regards to the data from this study we hypothesize that serum PLTP is involved in the clearance of postprandial lipoproteins and this process is attenuated in diabetes. Since postprandial lipoproteins are atherogenic, the delay in clearance of these particles could play an important role in the development of atherosclerosis in patients with diabetes mellitus. 相似文献