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91.
The synthesis of Nalpha-fluorenylmethoxycarbonyl-trans-4-hydroxy-4-O-[(2,3,4,6-tetra-O-acetyl)-alpha-d-mannopyranosyl]-l-proline allyl ester and Nalpha-fluorenylmethoxycarbonyl-trans-4-hydroxy-4-O-[(2,3,4,6-tetra-O-benzoyl)-alpha-d-mannopyranosyl]-l-proline allyl ester is described. Glycosylation using K?nigs-Knorr conditions with a benzoyl protected glycosyl donor provided the optimum method. Removal of the allyl ester gave two mannosylated building blocks suitable for solid phase glycopeptide synthesis. 相似文献
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95.
Proteomics of European beech (Fagus sylvatica L.) seed dormancy breaking: influence of abscisic and gibberellic acids 总被引:1,自引:0,他引:1
Pawłowski TA 《Proteomics》2007,7(13):2246-2257
96.
Regulation of autophagy in bovine mammary epithelial cells 总被引:1,自引:0,他引:1
The bovine mammary gland undergoes intensive remodelling during the lactation cycle, and the escalation of this process is observed during dry periods. The main type of cell death responsible for bovine mammary gland involution is apoptosis; however, there are also a lot of cells exhibiting morphological features of autophagy during drying off. Our in vitro and in vivo studies of bovine mammary gland physiology suggest that the enhanced process of autophagy, observed at the end of lactation and during dry periods, is the result of: (1) decreased level of lactogenic hormones (GH, IGF-I), (2) decreased GH-R and IGF-IR alpha expression, (3) increased expression of auto/paracrine apoptogenic peptides (IGFBPs, TGFbeta), (4) increased influence of sex steroids (17beta-estradiol and progesterone) and (5) enhanced competition between the between the intensively developing fetus and the mother organism for nutritional and bioactive compounds. The above conditions may create a state of temporary malnutrition of mammary epithelial cells, which forces the cells to the induction of autophagy, as a mechanism for stabilizing intracellular supplies of energy and amino acids, especially during the enhanced activity of apoptogenic factors. 相似文献
97.
Fujarewicz K Kimmel M Lipniacki T Swierniak A 《IEEE/ACM transactions on computational biology and bioinformatics / IEEE, ACM》2007,4(3):322-335
The paper concerns the problem of fitting mathematical models of cell signaling pathways. Such models frequently take the form of sets of nonlinear ordinary differential equations. While the model is continuous in time, the performance index used in the fitting procedure involves measurements taken at discrete time moments. Adjoint sensitivity analysis is a tool which can be used for finding the gradient of a performance index in the space of parameters of the model. In the paper, a structural formulation of adjoint sensitivity analysis called the generalized backpropagation through time (GBPTT) is used. The method is especially suited for hybrid, continuous-discrete time systems. As an example, we use the mathematical model NF-kappaB of the regulatory module, which plays a major role in the innate immune response in animals. 相似文献
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Alex A. Pollen Aparna Bhaduri Madeline G. Andrews Tomasz J. Nowakowski Olivia S. Meyerson Mohammed A. Mostajo-Radji Elizabeth Di Lullo Beatriz Alvarado Melanie Bedolli Max L. Dougherty Ian T. Fiddes Zev N. Kronenberg Joe Shuga Anne A. Leyrat Jay A. West Marina Bershteyn Craig B. Lowe Bryan J. Pavlovic Arnold R. Kriegstein 《Cell》2019,176(4):743-756.e17
99.
Marzec-Wróblewska Urszula Kamiński Piotr Łakota Paweł Szymański Marek Wasilow Karolina Ludwikowski Grzegorz Jerzak Leszek Stuczyński Tomasz Woźniak Alina Buciński Adam 《Biological trace element research》2019,188(2):251-260
Biological Trace Element Research - We analyzed cobalt (Co), chromium (Cr), and lead (Pb) concentrations in human semen and catalase CAT activity in seminal plasma and the effects of their... 相似文献
100.
Rafal Krela Elzbieta Poreba Martyna Weglewska Tomasz Skrzypczak Krzysztof Lesniewicz 《Biochimica et Biophysica Acta (BBA)/General Subjects》2019,1863(3):521-527