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International scientific collaboration is very sensitive to political and economic changes in a country or a geopolitical region. Collaboration in research is reflected by the corresponding coauthorship of the published results which can be analysed with the help of bibliometric methods. Based on data from theScience Citation Index (SCI), the change of annual international coauthorship patterns ofBulgaria, Czechoslovakia, Hungary, Poland andRomania have been analysed for the periods 1981–1985 and 1984–1993, respectively. It is shown that international collaboration was not developing similarly in the countries under study. Whilst scientific communities of Hungary and Poland have already been opening in the early 80s, the international collaboration of the other East-European countries was still dominated by COMECON relations till 1989. As expected, since 1990 an increasing scientific collaboration with highly developed countries can be observed in all five countries. At the same time, scientific collaboration with the former communist countries shows a clear decline. The great share of international co-authorship links is some countries reflect various tendencies part of which are interpreted with the help of a cardiologic model. 相似文献
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Franziska Hornung Julia Rogal Peter Loskill Bettina Lffler Stefanie Deinhardt-Emmer 《International journal of molecular sciences》2021,22(7)
Obesity is a globally increasing health problem, entailing diverse comorbidities such as infectious diseases. An obese weight status has marked effects on lung function that can be attributed to mechanical dysfunctions. Moreover, the alterations of adipocyte-derived signal mediators strongly influence the regulation of inflammation, resulting in chronic low-grade inflammation. Our review summarizes the known effects regarding pulmonary bacterial and viral infections. For this, we discuss model systems that allow mechanistic investigation of the interplay between obesity and lung infections. Overall, obesity gives rise to a higher susceptibility to infectious pathogens, but the pathogenetic process is not clearly defined. Whereas, viral infections often show a more severe course in obese patients, the same patients seem to have a survival benefit during bacterial infections. In particular, we summarize the main mechanical impairments in the pulmonary tract caused by obesity. Moreover, we outline the main secretory changes within the expanded adipose tissue mass, resulting in chronic low-grade inflammation. Finally, we connect these altered host factors to the influence of obesity on the development of lung infection by summarizing observations from clinical and experimental data. 相似文献
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Franziska Dengler Sofia Sova Antti M. Salo Joni M. Mki Peppi Koivunen Johanna Myllyharju 《International journal of molecular sciences》2021,22(8)
The HIF prolyl 4-hydroxylases (HIF-P4H) control hypoxia-inducible factor (HIF), a powerful mechanism regulating cellular adaptation to decreased oxygenation. The gastrointestinal epithelium subsists in “physiological hypoxia” and should therefore have an especially well-designed control over this adaptation. Thus, we assessed the absolute mRNA expression levels of the HIF pathway components, Hif1a, HIF2a, Hif-p4h-1, 2 and 3 and factor inhibiting HIF (Fih1) in murine jejunum, caecum and colon epithelium using droplet digital PCR. We found a higher expression of all these genes towards the distal end of the gastrointestinal tract. We detected mRNA for Hif-p4h-1, 2 and 3 in all parts of the gastrointestinal tract. Hif-p4h-2 had significantly higher expression levels compared to Hif-p4h-1 and 3 in colon and caecum epithelium. To test the roles each HIF-P4H isoform plays in the gut epithelium, we measured the gene expression of classical HIF target genes in Hif-p4h-1−/−, Hif-p4h-2 hypomorph and Hif-p4h-3−/− mice. Only Hif-p4h-2 hypomorphism led to an upregulation of HIF target genes, confirming a predominant role of HIF-P4H-2. However, the abundance of Hif-p4h-1 and 3 expression in the gastrointestinal epithelium implies that these isoforms may have specific functions as well. Thus, the development of selective inhibitors might be useful for diverging therapeutic needs. 相似文献
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Janine Glänzel Arnd Meyer Roman Unger Michael Bräunig Volker Wittstock Steffen Ihlenfeldt 《The International Journal of Advanced Manufacturing Technology》2017,88(5-8):1279-1288
A new interdisciplinary approach is discribed to identifying unknown parameters using an extended version of the known interval bisection method. This developed method is based on the use of finite elements for calibrating the simulation calculation. The resulting thermo-elastic deformations which occur in drilling processes with impaired cooling lubrication are to be used as correction values for tool positioning in the NC control. Based on the strong impact on workpiece temperature of machining, a simulation approach is presented for calculating the temperature fields and their thermo-elastic consequences. In addition, methods are presented to correct these effects. This paper particularly deals with the temperature fields of drilling operations. Special attention is paid to the technique employed for iterative numerical determination of the unknown heat flux η w and heat transfer coefficient \(\bar {\gamma }\) values. Finally, the data obtained from experiments are compared with those achieved by numerical simulation in order to verify the efficiency of simulation and determination of parameters. 相似文献
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Dipl. Soz.-Päd Katharina Seibel M.A. Franziska Krause M.A. Prof. Dr. med. Dipl.-Theol. Dipl.-Caritaswiss. Gerhild Becker M.Sc. Palliative Care 《Ethik in der Medizin》2014,26(1):47-58
Definition of the problem
Establishing a good physician–patient relationship based on mutual trust and professional responsibility is a central element in physicians’ professionalism. Recently, however, there has been considerable debate in the field of medical ethics regarding trends toward an economic approach to medicine, which could potentially undermine healthy doctor–patient relationships. Part of this economic approach to medicine involves viewing the patient as an autonomous customer. But what does the customer role mean for vulnerable patients who are restricted in their autonomy and what effect does it have on the physician–patient relationship?Arguments
In the following article, we pursue the question whether the physicians’ responsibility and the physician–patient relationship change when the (vulnerable) patient attributes the customer role to him-/herself. The study was conducted within the field of palliative care because terminally ill patients represent an especially vulnerable patient population. We base our argumentation in this article on the results of a qualitative interview study that investigated terminally ill patients’ attitudes regarding the topic “the patient as customer” as well as autonomy and decision-making.Conclusion
The interview results show that autonomy must be understood in relational terms; furthermore, the analysis of the interviews indicates that the physician plays a crucial role in enabling the patient’s autonomy, regardless of whether patients view themselves as a patient or a customer. Subsequently, we deliberate whether the patients’ statements point to potential changes in the doctor–patient relationship and physicians’ responsibility towards patients. Based on these findings, practical implications for the doctor–patient relationship are considered in regard to the “Ethics of Care”, emphasizing the need for an individualized approach to working with patients, especially those with particularly vulnerable conditions. 相似文献9.
Felix Schmutzler Christopher Zschiesche Juliane Titus David Poppitz Jens Freiding Rainer Rakoczy Andreas Reitzmann Roger Gläser 《化学,工程师,技术》2021,93(6):981-989
The hydroisomerization of two long-chain n-alkane mixtures was investigated over bifunctional Pt/H-ZSM-5 catalysts before and after dealumination of preshaped zeolite/binder pellets. The hydroisomerization over the dealuminated catalysts leads to more isomers and less cracking products. Consequently, higher ratios of multi- to mono-branched isomerization products are formed as expected for large- rather than medium-pore zeolites. This indicates a higher availability of space in the vicinity of the active sites and provides an attractive route to make medium-pore zeolites suitable for upgrading higher boiling hydrocarbon feeds. 相似文献
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