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991.
992.
E. Fanghnel R. Herrmann J. Bierwisch H. Hartung U. Baumeister G. Maier H. P. Reisenauer 《Advanced Synthesis \u0026amp; Catalysis》1994,336(5):444-451
Alkylthiosubstituted Bis(benzene-1,2-dithiolato)zincates, Benzene-1,2-dithioles, and -1,2-dithiolates – Educts for Dibenzo[c,g](1,2,5,6)tetrathiocins, and Benzo[c](1,2,3)trithioles; Investigations on Benzodithietes and ortho-Dithiobenzochinones Using benzenehexathiolate 1 it is possible to synthesize alkylthio-substituted benzo-1,3-dithiole-2-thiones 2 , or -ones 3 and benzo-di(1,3-dithiole-2-thiones) 4 , or -ones 5 , resp., which were cleaved under basic conditions. The generated benzene-1,2-dithiolates 7 were isolated as benzene-dithiolato zincates 8 , benzene-1,2-dithioles 11 , and benzene-1-thiole-2-thiolates 10 . Dibenzo[c,g](1,2,5,6)-tetrathiocins 9 were synthesized by oxidation of 7 or 8 in good yields. For the per(methylthio)-substituted tetrathiocin 9a the twist conformation was proved by x-ray structure analysis. The tetrathiocin 9a was probably formed via the orthodithiobenzoquinone 13a . Photolysis of 3a at room temperature in solution led to 9a and tetrakis(methylthio)benzo[c] (1,2,3)trithiole 12a as the main product, which was also formed by irradiation of 9a . The trithioles 12 were formed from 8 by reaction with sulfur dichloride. 12a was investigated by x-ray structure analysis. ortho-Dithiobenzoquinone 13c can be claimed as an intermediate upon irradiation of benzo-1,3-dithiol-2-one 3c in an argon matrix at 10 K. Depending on the wavelength the equilibrium lies either on the side of dithiobenzoquinone 13c or benzodithiete 14c . The same is true for system 15/16 , which can be reached by flash vacuum pyrolysis of 3c . 相似文献
993.
Automated Enzymatic Determination of Glucose, Maltose and Starch on Microtiter Plates. An automated enzymatic method for the determination of sugars and starch is described. The elimination of inherent methodical errors in the optical measurement of microtiter plates and the evalution of 96 raw data is done with the “LBR1993” software. Analysis is based on a 10min hydrolysis by glucoamylase at room temperature and determination of glucose with the GOD-PAP-method. A recovery of greater 99% for maize and potato starch is possible if the starch is transformed at 100°C by α-amylase to α-dextrins and converted in a second step with 8.88 g glucoamylase/g substrate to glucose. Solubilization of potato starch in 1 N sodium hydroxide at room temperature gives a recovery of 93%. Heating (60°C) in 0.5 N sodium hydroxide (AFNOR-method) is not suitable for sugar analysis and certain kinds of starch. 相似文献
994.
Gabriela Antonio-Andres Gustavo U. Martinez-Ruiz Mario Morales-Martinez Elva Jimnez-Hernandez Estefany Martinez-Torres Tania V. Lopez-Perez Laura A. Estrada-Abreo Genaro Patino-Lopez Sergio Juarez-Mendez Víctor M. Davila-Borja Sara Huerta-Yepez 《International journal of molecular sciences》2022,23(3)
995.
Madelene Lindkvist Mulugeta M. Zegeye Magnus Grenegrd Liza U. Ljungberg 《International journal of molecular sciences》2022,23(3)
Vascular endothelial cells express glycoprotein 130 (gp130), which is utilized as a signaling receptor by cytokines in the interleukin-6 (IL-6) family. Several IL-6 family cytokines can be found in the circulatory system during physiological or pathological conditions, and may influence endothelial function and response. This study evaluated and compared the cellular and molecular responses induced by IL-6 family cytokines in human endothelial cells. A proteomic analysis showed that IL-6 family cytokines induce the release of a range of proteins from endothelial cells, such as C-C motif chemokine ligand 23, hepatocyte growth factor, and IL-6. Pathway analysis indicated that gp130-signaling in endothelial cells regulates several functions related to angiogenesis and immune cell recruitment. The present investigation also disclosed differences and similarities between different IL-6 family cytokines in their ability to induce protein release and regulate gene expression and intracellular signaling, in regards to which oncostatin M showed the most pronounced effect. Further, this study showed that soluble gp130 preferentially blocks trans-signaling-induced responses, but does not affect responses induced by classic signaling. In conclusion, IL-6 family cytokines induce both specific and overlapping molecular responses in endothelial cells, and regulate genes and proteins involved in angiogenesis and immune cell recruitment. 相似文献
996.
Investigations on the Amylose Determination in High Protein Starch Source Materials, Especially Peas. The proposed utilization of amylose rich starches requires different methods of amylose determination. In addition to laboratory methods also simple tests are important to that. Because the discussed legume starches are hardly investigated, first of all the suitability of the amperometric iodine titration had to be checked. Then a more easier work was described. In the case of routine analyses a modified test procedure was compared with the method of iodine titration. 相似文献
997.
A Half-kernel Method for Determination of the Amylose Content of Barley. A method, which can determine the amylose content of a single kernel, is of importance for the use of amylose mutants in plant breeding. In this paper a potentiometric titration for the determination of the amylose content of a matured half kernel of barley is described and the evalution of the titration-curves is discussed. This method allows to differentiate between various barley lines and varieties in genotypes which differ in amylose content. 相似文献
998.
Poya Kavianpour Madeleine C. M. Gemmell Dr. Jan U. Kahlert Prof. Louis M. Rendina 《Chembiochem : a European journal of chemical biology》2020,21(19):2786-2791
Histone deacetylase enzymes (HDACs) are responsible for the global silencing of tumour-suppressor genes. Treatment with a histone deacetylase inhibitor (HDACi) can reverse this process and restore normal cell function. Herein, we report a small series of boron-based (boronic acid, boronate ester and closo-1,2-carborane) HDAC2 inhibitors with IC50 values in the nanomolar range. The boronate ester 4 b was the most potent compound assessed in this study (IC50=40.6±1.5 nM), followed closely by the 1,2-closo-carborane (IC50=42.9±1.5 nM). Compound 4 b exceeds the potency of the related gold-standard HDAC pan-inhibitor vorinostat ( 1 ) toward this particular HDAC isoform. 相似文献
999.
Hugo R. Fernandes Anuraag Gaddam Dilshat U. Tulyaganov José M. F. Ferreira 《International Journal of Applied Ceramic Technology》2020,17(1):64-74
Recycling has emerged as an environmental key point due to the diminishing of natural resources and the generation of ever-increasing amounts of industrial solid wastes. Glass wastes are among the materials that attract great interest in the recycling concept. This work presents the results of foams production from four series of compositions. The first series comprises powders of a sodium-calcium-silicate sheet glass cullet as the main component, an alkali-earth aluminosilicate glass as an additive, and a reagent grade silicon carbide (SiC) powder as gassing agent. In the second series, the glass cullet was used in combination with fly ashes (FLA) as main components, while SiC waste from abrasive paper served as foaming agent. In the third and fourth series, carbonates (calcite and dolomite) were used for foaming powder mixtures composed of sheet glass cullet and FLA, and powdered cathode ray tube panel glasses, respectively. All the processing parameters, including the main components, the nature and content of foaming agents are shown to play a crucial role on the foaming ability and final properties of the glass foams. 相似文献
1000.