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781.
782.
Hans W. Heldt Archie R. Portis Ross McC.Lilley Annemarie Mosbach Chong Ja Chon 《Analytical biochemistry》1980,101(2):278-287
This report describes a method for a sensitive assay of phosphate-containing metabolites in chloroplasts. The first step was to preincubate the chloroplasts with inorganic [32P]phosphate in order to label the stromal phosphate pool. On illumination, the intermediates of the reductive CO2 fixation cycle, and also ADP and ATP, were radioactively labeled. After a metabolic stop by filtering centrifugation into perchloric acid, the resulting extract was chromatographed on a small ion exchange column with a formic acid-formate gradient. The separated substances which appeared in the eluate were detected by continuous monitoring of 32P radioactivity. The identity of the peaks in the chromatogram and the reproducibility of the assay procedure were investigated. 相似文献
783.
784.
Müssbichler Anni Umrath Karl 《Journal of comparative physiology. A, Neuroethology, sensory, neural, and behavioral physiology》1950,32(4):311-318
Journal of Comparative Physiology A - 相似文献
785.
A Lange R Fetting B Ja?wiec A Moniewska J Ennen M Ernst H D Flad 《Cellular immunology》1991,133(2):285-294
Low-density human lymphocytes cultured with recombinant interleukin 2 (rIL-2) generated a high level of interferon(s) (IFN). Consistently more IFN including IFN-tau was produced during the first 3 days of culture with rIL-2 than during the subsequent 4 days. That ability was mainly associated with mepacrine+ cells and was decreased by low concentrations of leucine methyl ester (Leu-O-Me) or ammonium chloride. Leu-O-Me was employed either for the pretreatment of cells before the culture or as the additive to culture medium. The decrease in IFN production after pretreatment was associated with enhanced rIL-2-activated cytotoxicity. Similarly, 1 mM of ammonium chloride or 1 mM of Leu-O-Me added to rIL-2 supplemented cultures for 3 days showed an association between inhibition of IFN-tau generation and increased activation of cytotoxic activity. Thus NK cells appear to regulate their own response to rIL-2 activation and the control mechanism seems to be associated with the ability of the cells to produce IFN(s) and possibly other cytokines. 相似文献
786.
787.
Bożena Spichalska Adam Lesner Magdalena Wysocka Marcin Śledź Anna Łȩgowska Anna Jaśkiewicz Hanna Miecznikowska Krzysztof Rolka 《Journal of peptide science》2008,14(8):917-923
Combinatorial chemistry approach was applied to design chromogenic substrates of human beta-tryptase. The most active substrate, Ala-Ala-Pro-Ile-Arg-Asn-Lys-ANB-NH(2), was selected from among over 9 million heptapeptides. The amide of 5-amino-2-nitrobenzoic acid (ANB-NH(2)) attached at the C-terminus served as a chromophore. In order to determine the optimal length of the tryptase substrate, a series of N-terminally truncated fragments of this substrate was synthesized. Pro-Ile-Arg-Asn-Lys-ANB-NH(2), with the determined value of the specificity constant (k(cat)/K(M)) above 9 x 10(6) M(-1) s(-1), appeared to be the most specific substrate of tryptase. This substrate was twice as active as the parent heptapeptide substrate. We postulate that the optimal size of the pentapeptide substrate for the interaction with human beta-tryptase is associated with the unique structure of this proteinase, comprising four almost identical monomer subunits arranged in a square flat ring with its substrate pockets faced inside, forming a tetramer with a central pore that can be penetrated by this short peptide. Copyright (c) 2008 European Peptide Society and John Wiley & Sons, Ltd. 相似文献
788.
H Jańska A Kubicz A Szalewicz 《Comparative biochemistry and physiology. B, Comparative biochemistry》1989,92(2):341-346
1. AcPase III and AcPase IV, the major enzyme forms of the LMW AcPase of the frog (Rana esculenta) liver were resolved and purified to homogeneity. 2. AcPase III and IV showed a single protein band on SDS-PAGE corresponding to a mol. wt (Mr) of about 35,000. The Mr of the native enzyme forms were 33,200 (gel electrophoresis) and 38,200 +/- 5000 (gel filtration). This indicates that they are monomeric proteins sharing the same protein molecule. 3. AcPase III and IV differ essentially in thermostability and the activating effect of ConA binding. 4. AcPase III and IV are considerably activated with DTT but they differed markedly by the extent of this activation and the accompanying changes of their pH-activity curves. 5. It is suggested that the frog liver LMW AcPase represents a set of glycoforms whose different bioactivity is determined by the redox states of their essential cysteine residues. 相似文献
789.
Results of chemotherapy applied in 23 patients with anaplastic thyroid cancer are presented. Chemotherapy combined with local treatment is a suggested therapy for treatment the locally advanced anaplastic thyroid cancer. 相似文献