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11.
12.
I E Wi?niewska Z Gawlik M Sasinowska-Motyl 《Folia histochemica et cytobiologica / Polish Academy of Sciences, Polish Histochemical and Cytochemical Society》1985,23(1-2):51-59
Using the interferometric technique the authors studied the effect of simultaneous administration of ibuprofen (Polfa) and ethanol on the activity of alkaline phosphatase in the proximal jejunum. Both ibuprofen and ethanol cause in the digestive tract functional and morphological changes. The used technique of quantitative determination of alkaline phosphatase activity at the site of its primary location made possible an assessment of changes in the activity of the enzyme caused by the administered agents. It was found that after 60 days of the experiment both agents caused a statistically greater changes were observed in the rats receiving both these agents simultaneously. The obtained results suggest the conclusion that simultaneous administration of ibuprofen and ethanol causes in the mucosal gland in the proximal small intestine development of an interaction of the additive. 相似文献
13.
1H NMR spectroscopy and X-ray diffraction data are described for N-(2,3,4,6-tetra-O-acetyl-beta-D-galactopyranosyl)pyridinium bromide and N-(beta-D-galactopyranosyl)pyridinium bromide. X-ray crystallography revealed that the O-acetylated salt crystallizes with two molecules of water and one molecule of ethanol. 相似文献
14.
Chmiela M Jurkiewicz M Wiśniewska M Czkwianianc E Płaneta-Małecka I Rechciński T Rudnicka W 《Acta microbiologica Polonica》1999,48(3):277-281
A role of autoimmune processes in the pathology of Helicobacter pylori infections has been suggested. The Lewis determinants present in LPS molecule of H. pylori bacteria have been indicated as the cause of antigenic mimicry. In this study, the prevalence of IgM and IgG antibodies to Lewis X antigen in the sera from children and adults, with or without dyspepsia, infected or not infected with H. pylori, seropositive and seronegative for anti-H. pylori IgG were determined immuno-enzymatically (ELISA). Our results revealed that humans may produce anti-Lewis X antibodies, particularly of IgM class, in the absence of H. pylori infection or H. pylori independent dyspepsia. The production of such antibodies, by healthy children who had never been infected with H. pylori suggested that anti-Lewis X antibodies may occur naturally. 相似文献
15.
Jin-Hong?KimEmail author Myung-Hwa?Baek Byung?Yeoup?Chung Seung?Gon?Wi Jae-Sung?Kim 《Journal of Plant Biology》2004,47(4):314-321
To characterize the stimulatory effects of low-dose gamma radiation on early plant growth, we investigated alterations in
the photosynthesis and antioxidant capacity of red pepper (Capsicum annuum L.) seedlings produced from gamma-irradiated seeds. For two cultivars (Yeomyung and Joheung), three irradiation groups (2,
4, and 8 Gy, but not 16 Gy) showed enhanced development, although Fv/Fm, the maximum photochemical efficiency of Photosystem
II (PSII), did not differ significantly among any of the four groups. In contrast, values for 1/Fo — 1/Fm, i.e., a measure
of functional PSII content, decreased in the irradiated groups of ‘Yeomyung’ but increased in those of ‘Joheung’. Pigment
analyses and enzyme activity assays revealed that irradiation altered the compositions of photosynthetic pigments (chlorophylls
and carotenoids) as well as the activities of antioxidant enzymes (superoxide dismutase and glutathione reductase). However,
these shifts were not directly related to the increase in early growth, although they were cultivar-and developmental stage-dependent
In addition, the effects of irradiation on the enzymatic activities measured here were at opposition between the two cultivars. 相似文献
16.
Falkiewicz B Wiśniowski W Kołodziejczyk AS Wiśniewski K 《Nucleosides, nucleotides & nucleic acids》2001,20(4-7):1393-1397
We have synthesised a series of new chiral type I peptide nucleic acid monomers in total yields of 36-53%, derived from Val, Ile, Ser(Bzl), Pro, and Trp, employing convenient procedure. 相似文献
17.
Nowacki A Smiataczowa K Kasprzykowska R Dmochowska B Wiśniewski A 《Carbohydrate research》2002,337(3):265-272
Four isomers of methyl 2-deoxy-D-arabino-hexosides were isolated by HPLC as chromatographically homogeneous compounds. The rates of pyranoside isomerization (alpha(p) and beta(p)) at 40 degrees C and of furanoside isomerization (alpha(f) and beta(f)) at 26 degrees C were determined. A mechanism has been suggested for transformations taking place during isomerization of methyl 2-deoxy-D-arabino-hexosides in methanolic solution catalyzed with hydrogen chloride. 相似文献
18.
Kusakiewicz-Dawid A Bugaj M Dzik JM Gołos B Wińska P Pawełczak K Rzeszotarska B Rode W 《Acta biochimica Polonica》2002,49(1):197-203
2-Deamino-2-methyl-N10-propargyl-5,8-dideazafolic acid (ICI 198583) is a potent inhibitor of thymidylate synthase. Its analogue, N(alpha)-[4-[N-[(3,4-dihydro-2-methyl-4-oxo-6-quinazolinyl)methyl]-N-propargylamino]phenylacetyl]-L-glutamic acid, containing p-aminophenylacetic acid residue substituting p-aminobenzoic acid residue, was synthesized. The new analogue exhibited a moderately potent thymidylate synthase inhibition, of linear mixed type vs. the cofactor, N(5,10)-methylenetetrahydrofolate. The Ki value of 0.34 microM, determined with a purified recombinant rat hepatoma enzyme, was about 30-fold higher than that reported for inhibition of thymidylate synthase from mouse leukemia L1210 cells by ICI 198583 (Hughes et al., 1990, J. Med. Chem. 33, 3060). Growth of mouse leukemia L5178Y cells was inhibited by the analogue (IC50 = 1.26 mM) 180-fold weaker than by ICI 198583 (IC50 = 6.9 microM). 相似文献
19.
20.
The amount of polyamines (such as putrescine, spermidine, and spermine) increased under environmental stress conditions. We used transgenic technology in an attempt to evaluate their potential for mitigating the adverse effects of several abiotic stresses in plants. Because there is a metabolic competition for S-adenosylmethionine as a precursor between polyamine (PA) and ethylene biosyntheses, it was expected that the antisense-expression of ethylene biosynthetic genes could result in an increase in PA biosynthesis. Antisense constructs of cDNAs for senescence-related 1-aminocyclopropane-1-carboxylic acid (ACC) synthase (CAS) and ACC oxidase (CAO) were isolated from carnation flowers that were introduced into tobacco by Agrobacterium-mediated transformation. Several transgenic lines showed higher PA contents than wild-type plants. The number and weight of seeds also increased. Stress-induced senescence was attenuated in these transgenic plants in terms of total chlorophyll loss and phenotypic changes after oxidative stress with hydrogen peroxide (H2O2), high salinity, acid stress (pH 3.0), and ABA treatment. These results suggest that the transgenic plants with antisense CAS and CAO cDNAs are more tolerant to abiotic stresses than wild-type plants. This shows a positive correlation between PA content and stress tolerance in plants. 相似文献