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81.
Lars Libuda Madlen Stimming Christina Mesch Petra Warschburger Hermann Kalhoff Berthold Viktor Koletzko Mathilde Kersting 《European journal of nutrition》2014,53(6):1335-1344
Purpose
German guidelines recommend breast milk as ideal for infant’s nutrition, supporting exclusive breastfeeding for at least 4 months. Moreover, in mothers with insufficient fish intake, DHA status may be improved by supplementation during pregnancy and lactation. However, little is known on current rates of breastfeeding and DHA supplementation in Germany. The objective of this study was to analyse frequencies and demographic determinants of breastfeeding and DHA supplementation in Germany.Methods
Data derived from a nationwide consumer survey of 986 mothers with children between 5 and 36 months of age in Germany.Results
78.3 % reported that they ever breastfed their children, and 55.6 % of the mothers exclusively breastfed for at least 4 months. Mothers who did not breastfeed were less likely to be informed by their paediatrician or midwife and were more often not informed at all; 27.8 % of mothers used DHA supplements during pregnancy, 16.8 % postnatal. DHA supplementation was more common in women with a high versus a low fish intake. The social status was the major determinant of breastfeeding initiation and exclusivity and also DHA supplementation.Conclusion
Breastfeeding initiation and duration of exclusive breastfeeding in Germany need to be improved. Professional counselling and support, with a focus on mothers from lower social classes, appears necessary to increase current rates of breastfeeding initiation, duration, and exclusiveness, but also to ensure a sufficient supply with DHA in pregnant and lactating women, particularly in women with low fish consumption. 相似文献82.
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85.
Evaluation of the biocompatibility of root canal sealers on human periodontal ligament cells ex vivo
Jung Susanne Libricht Viktor Sielker Sonja Hanisch Marcel R. Schäfer Edgar Dammaschke Till 《Odontology / the Society of the Nippon Dental University》2019,107(1):54-63
Odontology - The aim of this study was to evaluate the biocompatibility of two comparatively new calcium silicate containing sealers (MTA-Fillapex and BioRoot-RCS) with that of two established... 相似文献
86.
Kemenesi Gábor Kornya László Tóth Gábor Endre Kurucz Kornélia Zeghbib Safia Somogyi Balázs A. Zöldi Viktor Urbán Péter Herczeg Róbert Jakab Ferenc 《Age (Dordrecht, Netherlands)》2020,42(4):1093-1099
GeroScience - The global impact of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic is significant in terms of public health effects and its long-term socio-economic... 相似文献
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Alexander A. Bukreyev Kartik Chandran Olga Dolnik John M. Dye Hideki Ebihara Eric M. Leroy Elke Mühlberger Sergey V. Netesov Jean L. Patterson Janusz T. Paweska Erica Ollmann Saphire Sophie J. Smither Ayato Takada Jonathan S. Towner Viktor E. Volchkov Travis K. Warren Jens H. Kuhn 《Archives of virology》2014,159(4):821-830
The International Committee on Taxonomy of Viruses (ICTV) Filoviridae Study Group prepares proposals on the classification and nomenclature of filoviruses to reflect current knowledge or to correct disagreements with the International Code of Virus Classification and Nomenclature (ICVCN). In recent years, filovirus taxonomy has been corrected and updated, but parts of it remain controversial, and several topics remain to be debated. This article summarizes the decisions and discussion of the currently acting ICTV Filoviridae Study Group since its inauguration in January 2012. 相似文献
89.
Viktria Goldschmidt Gz Adrienn Nagy Viktor Farkas Ern Keszei Andrs Perczel 《RSC advances》2019,9(53):30720
Nowadays, in Solid Phase Peptide Synthesis (SPPS), being either manual, automated, continuous flow or microwave-assisted, the reaction with various coupling reagents takes place via in situ active ester formation. In this study, the formation and stability of these key active esters were investigated with time-resolved 1H NMR by using the common PyBOP/DIEA and HOBt/DIC coupling reagents for both α- and β-amino acids. Parallel to the amide bond formation, the hydrolysis of the α/β-active esters, a side reaction that is a considerable efficacy limiting factor, was studied. Based on the chemical nature/constitution of the active esters, three amino acid categories were determined: (i) the rapidly hydrolyzing ones (t < 6 h) with smaller (Ala) or even longer side chains (Arg) holding a large protecting group; (ii) branched amino acids (Ile, Thr) with slowly hydrolyzing (6 < t < 24 h) propensities, and (iii) non-hydrolyzing ones, such as the hard-to-couple β-amino acids or β-sugar amino acid derivatives, stable for longer times (t > 24 h) in solution. The current insight into the kinetics of this key hydrolysis side reaction serves as a guide to optimize the coupling conditions of α- and β-amino acids, thereby saving time and minimizing the amounts of reagents and amino acids to be used – all key factors of more environmentally friendly chemistry.Parallel to the amide bond formation, the hydrolysis of the active esters of α/β-amino acids, as an unwanted side reaction limiting coupling efficacy, is studied. 相似文献
90.
The study of hydrogen storage properties of Mg-based thin films is of interest due to their unique composition, interface, crystallinity, and high potential for use in hydrogen-storage systems. Alloying Mg with Al leads to the destabilization of the magnesium hydride reducing the heat of reaction, increases the nucleation rate, and decreases the dehydriding temperature. The purpose of our study is to reveal the role of the aluminum atom addition in hydrogen adsorption and accumulation in the Mg-H solid solution. Ab initio calculations of aluminum and hydrogen binding energies in magnesium were carried out in the framework of density functional theory. Hydrogen distribution and accumulation in Mg and Mg-10%Al thin films were experimentally studied by the method of glow-discharge optical emission spectroscopy and using a hydrogen analyzer, respectively. It was found that a hydrogen distribution gradient is observed in the Mg-10%Al coating, with more hydrogen on the surface and less in the bulk. Moreover, the hydrogen concentration in the Mg-10%Al is lower compared to Mg. This can be explained by the lower hydrogen binding energy in the magnesium-aluminum system compared with pure magnesium. 相似文献