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排序方式: 共有493条查询结果,搜索用时 187 毫秒
61.
Tanja Gärtner Erhard Gernand Jutta Gottschalk Karsten Donat 《Journal of dairy science》2019,102(10):9187-9199
In the transition period from late gestation to early lactation, dairy cows undergo tremendous metabolic changes. Insulin is a relevant antilipolytic factor. Decreasing serum concentrations of insulin and glucose, increasing serum concentrations of nonesterified fatty acids (NEFA) and β-hydroxybutyrate (BHB), and changes in body condition score (BCS) reflect the negative energy balance around calving. This study investigated peripartum metabolic adaptation in 359 primiparous and 235 multiparous German Holstein cows from a commercial dairy herd under field conditions. Body condition score was recorded and blood samples were taken 10 to 1 d prepartum, 2 to 4 d postpartum, and 12 to 20 d postpartum. Generalized mixed models and generalized estimation equations were applied to assess associations between prepartum BCS; BCS changes during the transition period; insulin, glucose, NEFA, and BHB serum concentrations; and milk yield, which was taken from an electronic milk meter from d 6 of lactation. Serum insulin concentrations of multiparous postpartum cows were lower compared with prepartum, and compared with primiparous cows. In general, primiparous cows had lower postpartum NEFA and BHB concentrations than multiparous cows. In primiparous cows, we identified a positive association between prepartum BCS and prepartum serum insulin concentration. Prepartum obese multiparous cows, but not primiparous cows, were characterized by higher postpartum serum NEFA and BHB concentrations and lower milk yield than other cows in the same parity class. Primiparous cows with a smaller degree of BCS loss during the transition period had higher postpartum insulin and lower NEFA concentrations and lower milk yield than other primiparous cows. In conclusion, primiparous cows had less lipolysis and lower milk yield than multiparous cows, associated with higher insulin concentrations. Avoiding high body condition loss during the transition period is a main factor in preventing peripartal metabolic imbalances of glucose and fat metabolism. 相似文献
62.
Digestibility and allergenicity of β-lactoglobulin following laccase-mediated cross-linking in the presence of sour cherry phenolics 总被引:1,自引:0,他引:1
Ziyad Tantoush Dragana Stanic Marija Stojadinovic Jana Ognjenovic Luka Mihajlovic Marina Atanaskovic-Markovic Tanja Cirkovic Velickovic 《Food chemistry》2011
β-Lactoglobulin (BLG) is an important nutrient of dairy products, but it represents a serious health risk in patients allergic to milk. Sour cherry (Prunus cerasus L.) extract (SCE) is frequently added as a natural food colour in composite foods, such as fruit yogurt, ice creams, frappés and milkshakes. The aim of this study was to investigate the potential of laccase to cross-link BLG in the presence of an SCE and to characterise the obtained products for their bioactivity. 相似文献
63.
Dr. Santina Maiorana Prof. Roberta Ettari Dr. Santo Previti Dr. Giorgio Amendola Dr. Annika Wagner Prof. Sandro Cosconati Prof. Ute A. Hellmich Prof. Tanja Schirmeister Prof. Maria Zappalà 《ChemMedChem》2020,15(16):1552-1561
In this paper, we report the design, synthesis and biological investigation of a series of peptidyl vinyl ketones obtained by modifying the P2 fragment of previously reported highly potent inhibitors of rhodesain, the main cysteine protease of Trypanosoma brucei rhodesiense. Investigation of the structure–activity relationship led us to identify new rhodesain inhibitors endowed with an improved selectivity profile (a selectivity index of up to 22 000 towards the target enzyme), and/or an improved antitrypanosomal activity in the sub-micromolar range. 相似文献
64.
65.
About 80% of all fire fatalities in Germany occur because of fires in homes. It has been known for some time that modern materials (synonym for materials consisting mostly of synthetic polymers) tend to burn differently from older materials (synonym for materials consisting mostly of fibrous cellulosic substances) and it has been acknowledged that the amount of combustible plastics in homes has increased significantly over the last decades. To investigate the influence of modern furniture and ventilation conditions of fires in homes, a series of four large‐scale tests in two living rooms (LRs) with adjacent rooms (ARs) was performed by BAM and the Frankfurt fire service. Two LRs, one with older furniture and one with modern furniture, were tested twice each. Each test started with the ignition of a paper cushion on an upholstered chair. The influence of modern materials on the fire development was investigated, as well as the influence of the ventilation on the fire development. In all settings, an upholstered chair was the first burning item. Results of the test series show that fires in rooms with modern furniture develop faster than fires in rooms with older furniture. This is true for temperature development in the rooms as well as for smoke production. 相似文献
66.
67.
Humidity Sensors: Lithium Tin Sulfide—a High‐Refractive‐Index 2D Material for Humidity‐Responsive Photonic Crystals (Adv. Funct. Mater. 14/2018)
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68.
Cysteine Proteases and Their Inhibitors 总被引:1,自引:0,他引:1
69.
Michael K. Hausmann Gilberto Siqueira Rafael Libanori Dimitri Kokkinis Antonia Neels Tanja Zimmermann Andr R. Studart 《Advanced functional materials》2020,30(4)
Cellulose is an attractive material resource for the fabrication of sustainable functional products, but its processing into structures with complex architecture and high cellulose content remains challenging. Such limitation has prevented cellulose‐based synthetic materials from reaching the level of structural control and mechanical properties observed in their biological counterparts, such as wood and plant tissues. To address this issue, a simple approach is reported to manufacture complex‐shaped cellulose‐based composites, in which the shaping capabilities of 3D printing technologies are combined with a wet densification process that increases the concentration of cellulose in the final printed material. Densification is achieved by exchanging the liquid of the wet printed material with a poor solvent mixture that induces attractive interactions between cellulose particles. The effect of the solvent mixture on the final cellulose concentration is rationalized using solubility parameters that quantify the attractive interparticle interactions. Using X‐ray diffraction analysis and mechanical tests, 3D printed composites obtained through this process are shown to exhibit highly aligned microstructures and mechanical properties significantly higher than those obtained by earlier additively manufactured cellulose‐based materials. These features enable the fabrication of cellulose‐rich synthetic structures that more closely resemble the exquisite designs found in biological materials grown by plants in nature. 相似文献
70.
Tommaso Marchesi D'Alvise Sean Harvey Lisa Hueske Jolanta Szelwicka Lothar Veith Tuomas P. J. Knowles Dennis Kubiczek Carolin Flaig Fabian Port Kay‐E. Gottschalk Frank Rosenau Bartlomiej Graczykowski George Fytas Francesco S. Ruggeri Katrin Wunderlich Tanja Weil 《Advanced functional materials》2020,30(21)
Cellular membranes have long served as an inspiration for nanomaterial research. The preparation of ultrathin polydopamine (PDA) films with integrated protein pores containing phospholipids and an embedded domain of a membrane protein glycophorin A as simplified cell membrane mimics is reported. Large area, ultrathin PDA films are obtained by electropolymerization on gold surfaces with 10–18 nm thickness and dimensions of up to 2.5 cm2. The films are transferred from gold to various other substrates such as nylon mesh, silicon, or substrates containing holes in the micrometer range, and they remain intact even after transfer. The novel transfer technique gives access to freestanding PDA films that remain stable even at the air interfaces with elastic moduli of ≈6–12 GPa, which are higher than any other PDA films reported before. As the PDA film thickness is within the range of cellular membranes, monodisperse protein nanopores, so‐called “nanodiscs,” are integrated as functional entities. These nanodisc‐containing PDA films can serve as semi‐permeable films, in which the embedded pores control material transport. In the future, these simplified cell membrane mimics may offer structural investigations of the embedded membrane proteins to receive an improved understanding of protein‐mediated transport processes in cellular membranes. 相似文献