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1.
2.
Judyta Kruk Irena Baranowska Bogusaw Buszewski Sylwia Bajkacz Bartosz Kowalski Magdalena Ligor 《Chirality》2019,31(2):138-149
Plant material is a rich source of valuable compounds such as flavanones. Their different forms influence bioavailability and biological activity, causing problems with the selection of plant material for specific purposes. The purpose of this research was to determine selected flavanone (eriodictyol, naringenin, liquiritigenin, and hesperetin) enantiomer contents in free form and bonded to glycosides by an RP‐UHPLC‐ESI‐MS/MS method. Different parts (stems, leaves, and flowers) of goldenrod (Solidago virgaurea L.), lucerne (Medicago sativa L.), and phacelia (Phacelia tanacetifolia Benth.) were used. The highest content of eriodictyol was found in goldenrod flowers (13.1 μg/g), where it occurred mainly as the (S)‐enantiomer, and the greatest proportion of the total amount was bonded to glycosides. The richest source of naringenin was found to be lucerne leaves (4.7 μg/g), where it was mainly bonded to glycosides and with the (S)‐enantiomer as the dominant form. Liquiritigenin was determined only in lucerne, where the flowers contained the highest amount (1.2 μg/g), with the (R)‐enantiomer as dominant aglycone form and the (S)‐enantiomer as the dominant glycosylated form. The highest hesperetin content was determined in phacelia leaves (0.38 μg/g), where it was present in the form of a glycoside and only as the (S)‐enantiomer. A comparison of the different analyte forms occurring in different plant parts was performed for the first time. 相似文献
3.
A robust method for selection of variables with the greatest discriminatory power is presented in the paper. The method deals with the two groups of data problem. An application of the method to some respiratory disease data and comparisons with classical procedures are given, also. 相似文献
4.
Summary A method of classification is presented, which divides histochemical visualization reactions into categories based on general reaction types. This scheme is dependent upon the reaction between two elements, the substrate and the probe. The substrate represents a tissue component(s) with one or more reactive groups that can combine directly with the probe. Alternatively, the substrate reactive groups are chemically modified (activation) with a suitable reagent before reaction with the probe. Probes are of three types: those that yield a coloured product, those that result in a colourless product, and those that produce a coloured product only after a further reaction.Methods used in carbohydrate histochemistry are divided into one, two and three probe reactions. Two probe reactions are further subdivided into sequences involving one or two coloured products (one and two dye sequences); three probe reactions into sequences involving one, two or three coloured products (one, two and three dye sequences). This classification permits the rationalization and organization of methods, and provides a framework for the examination of existing methods and the development of new ones. 相似文献
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6.
Jerzy Chelkowski 《Mycotoxin Research》1987,3(1):3-6
14C-roquefortine, given to ratsper os or intraperitoneally, was eliminated principally by the biliary route. Most of the given radiolabel accounted for had been voided within one day of administration. Roquefortine was not metabolised in rat liver homogenate but significant transformation to more polar products was evident in faeces. 相似文献
7.
Jerzy Chelkowski Piotr Zajkowski Marcin Zawadzki Juliusz Perkowski 《Mycotoxin Research》1987,3(1):25-32
An isolated rat liver was perfused with deoxynivalenol (DON) at a dose of 3 mg in a recirculating perfusion system. To identify glucuronide conjugates equal amounts of bile samples, perfusate and liver homogenates were incubated with and without (control) a β-glucuronidase preparation and analyzed by thin layer chromatography and capillary gas liquid chromatography — chemical ionization mass spectrometry. A total of 40.4% of the administered dose of DON was found to be conjugated with glucuronic acid (perfusate 20.4%, bile 19.2%, liver 0.8%), while only 1.3% of the parent DON (perfusate 1.1%, bile 0.2%) was detected. The cleavage of DON-glucuronide was demonstrated by incubating DON-glucuronide containing bile samples with intestine contents under anaerobic conditions. 相似文献
8.
Summary
Nocardia mediterranei strain LBG A3136 contains the 23.7 kb element pMEA100 in a chromosomally integrated form as well as in the free state (Moretti et al. 1985). The integrated form of this element can be excised precisely from the Nocardia chromosome without any accompanying rearrangements in flanking chromosomal DNA. After transfer into plasmid-free mutant strains, pMEA100 reintegrates site specifically into its original chromosomal locus. The exact mapping of the pMEA100 integration site was accomplished by restriction analysis and DNA sequencing. The attachment site of pMEA100, the junctions of its integrated form and plasmid-free chromosomal DNA of N. mediterranei contain an identical 47 bp long sequence which is probably required for site-specific recombination connected with integration and excision of pMEA100. Only one such sequence was found in the chromosome of pMEA100-free N. mediterranei derivatives as suggested by the single integration locus. 相似文献
9.
Jerzy S Nowak 《Journal of genetics》1987,66(2):133-138
Erythrocytes from healthy men were examined for the presence of complement (C3b) receptor using haemagglutination assay with human aggregated IgG (aggIgG) and guinea pig complement. The results were expressed as the intensity of haemagglutination that corresponded to the C3b receptor sites density as evidenced by radioimmunobinding results. Among normal men three phenotypes of complement receptor (CR) were distinguished: high (CRh/CRh) phenotype corresponding to strong agglutination, an intermediate (CRh/CRI) producing weak agglutination and low phenotype (CRI/CRI) that gave no agglutination. In a population of 517 normal men these three phenotypes occurred in 63.8, 30.6 and 5.6%, respectively. Frequencies of the genes responsible for high (CRh) and low (CRI) expression of erythrocyte C3b receptor were 0.791 and 0.209, respectively. 相似文献
10.
Stefan Einhorn Patrik Ling Nina Einhorn Hans Strander Jerzy Wasserman 《Cancer immunology, immunotherapy : CII》1987,24(3):190-196
Summary The influence of natural -interferon (-IFN) therapy (3×106 units i.m. daily) on blood lymphoid cells was studied in 20 patients with gynecological neoplasias (7 patients with condylomata accuminata and 13 patients with ovarian carcinoma). There was a statistically significant increase in the intracellular levels of 2'–5'oligoadenylate synthese 1 day after the first injection of IFN and with few exceptions this activity remained increased during 3 months of treatment. In most of the patients, the capacity of blood lymphoid cells to produce IgA, IgG, and IgM following stimulation with pokeweed mitogen was decreased 1 day after the first injection of IFN and with few exceptions it remained low during 6 months of IFN therapy. In most patients there was a decrease in the capacity of lymphoid cells to act as stimulator or responder cells in a mixed lymphocyte culture during IFN therapy. The -IFN therapy had no major influence on the response of lymphoid cells to mitogens. We conclude, that neither this nor our previous studies on the influence of IFN therapy on immunological functions have given support to the hypothesis that the antitumor action of IFN is mediated by the immune system. 相似文献