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991.
Magdalena Grabkowska-Drużyc Jan Balzarini Dorota G. Piotrowska 《Nucleosides, nucleotides & nucleic acids》2013,32(12):682-699
5-Aryl-2-methylisoxazolidin-3-yl-3-phosphonates have been synthesised from N-methyl-C-diethoxyphosphorylnitrone and vinyl aryls in good yields. Isoxazolidine phosphonates obtained herein were evaluated for activity against a broad range of DNA and RNA viruses. None of the compounds were endowed with antiviral activity nor cytostatic activity at 100 to 250 μM concentrations. 相似文献
992.
993.
Alessandro Sicorello Bartosz Różycki Petr V. Konarev Dmitri I. Svergun Annalisa Pastore 《Structure (London, England : 1993)》2021,29(1):70-81.e5
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994.
Aleš Imramovský Jarmila Vinšová Juana Monreal Férriz Rafael Doležal Josef Jampílek Jarmila Kaustová Filip Kunc 《Bioorganic & medicinal chemistry》2009,17(10):3572-3579
A new series of 30 N-protected amino acid esters were prepared as a part of ongoing search for new anti-tuberculosis active salicylanilides. The esters possess high in vitro activity against Mycobacterium tuberculosis, Mycobacterium avium, and two strains of Mycobacterium kansasii, where one is an isolate from the patient, with MIC in the range 1–32 μmol/L for all tested strains. The prepared esters can be considered as prodrugs with better bio-availability and as more efficient transport forms through the mycobacterial cell membranes due to the higher lipophilicity. The experimental and calculated lipophilicity, stability, antituberculotic activity, cytotoxicity as well as the quantitative structure–activity relationships (QSARs) explored by the Intelligent Problem Solver (IPS) in Trajan Neural Network Simulator 6.0 are presented. 相似文献
995.
In this study we discuss stacking interactions in cytosine dimer in conformations appearing in B-DNA crystals. The variational–perturbational scheme was applied for decomposition of the intermolecular interaction energy at the MP2 level of theory. The significant influence of the mutual orientation of cytosine monomers was observed not only on the total intermolecular interaction energy but also on its components: Different components of intermolecular interaction energy depend in different manner on parameters describing mutual orientation of cytosine monomers. 相似文献
996.
P. Adam O. Sobek M. Hybel’ová D. Doležil J. Kasík L. Hajduková D. Adam J. Svatoňová 《Folia microbiologica》2009,54(3):257-260
A very rare clinical entity, so-called eosinophilic meningitis, classified by prevalence of eosinophils in cerebrospinal fluid
(CSF), with the presence of pleiocytosis, has been recorded in our laboratory four times only in the last 24 years. A low
glucose level, elevation of total protein and lactic acid in CSF were detected in all the clinical cases. The last two cases
were made possible by using flow cytometry method; surprisingly, the presence was found in mature T-cells in CSF, predominantly
helpers (CD3+, CD4+) and, practically, none is B-cells (CD19+), plasma cells (CD138+) and NK-cells. 相似文献
997.
998.
H W Murray K E Squires C D Miralles M Y Stoeckle A M Granger A Granelli-Piperno C Bogdan 《Journal of immunology (Baltimore, Md. : 1950)》1992,148(6):1858-1863
In naive BALB/c mice, acquisition of resistance to Leishmania donovani and formation of antileishmanial tissue granulomas are linked expressions that require both L3T4+ and Lyt 2+ cells as well as both IL-2 and IFN-gamma. To determine the mechanisms of established resistance to L. donovani, rechallenged immune BALB/c mice were treated with T cell- and lymphokine-depleting mAb or cyclosporin A. In the liver, resistance to rechallenge was inhibited by treatment with anti-Lyt 2 but not anti-L3T4 mAb. Resistance was also impaired by anti-IL-2 treatment but not by anti-IFN-gamma mAb. The hepatic granulomatous response to rechallenge, however, was not impaired by either anti-Lyt 2 or anti-IL-2 mAb nor by anti-L3T4 or anti-IFN-gamma treatment. In contrast, cyclosporin A suppressed granuloma formation but not antileishmanial activity. These results indicate a particularly important antileishmanial host defense role for Lyt 2+ cells and IL-2 in sensitized animals, and when compared to prior observations in L. donovani-infected naive mice, suggest that 1) discrete T cell- and lymphokine-dependent mechanisms are involved in initial acquisition of resistance vs established immunity, 2) more than one mechanism can mediate the development of tissue granulomas, and 3) granuloma formation by itself may not be required nor necessarily sufficient to confer antimicrobial activity. 相似文献
999.
Comparison of tin and lead toxic action on erythropoietic system in blood and bone marrow of rabbits
Jadwiga Chmielnicka Grażyna Zareba Eugenia Polkowska-Kulesza Maria Najder Anna Korycka 《Biological trace element research》1993,36(1):73-87
The aim of this work was to assess and compare morphological changes in blood and bone marrow of rabbits afterper os (po) or intraperitoneal (ip) administration of equimolar doses of tin or lead. The experiment was performed on female rabbits that were divided into four groups of six animals each, and received stannous chloride SnCl2×2 H2O (Merck) or lead acetate Pb(CH3COO)2 (POCh Gliwice) in equimolar doses (ip—17/uM/kg) orper os (po—85/uM/kg). Group I was administered SnCl2 ip at the dose of 2 mg Sn/kg every day for 3 mo, group II Pb(CH3COO)2 ip at a dose of 3.5 mg Pb/kg every day for 3 wk, group III po SnCl2 (10 mg Sn/kg), and group IV po Pb(CH3COO)2 (17.5 mg Pb/kg), both for 4 mo. The morphological factors hemoglobin (Hb), hematocrit (Ht), erythrocyte (Ercs), and reticulocyte counts, MCV, MCH, MCHC, and erythropoietic system in bone marrow aspirates with sideroblast count, iron concentration, TIBC, and SI were estimated. Tin caused hemolytic anemia depending on abnormal iron utilization. After ip administration of tin, anemia was observed during the whole time of the study, whereas after po exposure, transient anemia was noticed. It has been proven that the mechanism of toxic action of tin on hematopoietic system is similar to the toxic effect of lead. 相似文献
1000.
Włodzimierz Maśliński Ewa Grabczewska Jan Ryżewski 《Biochimica et Biophysica Acta (BBA)/General Subjects》1980,633(2):269-273
The conditions of the binding of acetylcholine have been studied in lymphocytes isolated from rat peripheral lymph nodes. Acetylcholine appeared to penetrate the lymphocyte membrane. We have confirmed the presence of muscarinic receptors, which, however, are not involved in transport of acetylcholine through the membrane. The receptors of the nicotine type on lymphocytes are demonstrated by the decrease of acetylcholine binding in the presence of a specific antagonist, tubocurarine. These nicotinic receptors may be involved in acetylcholine transport into the cells. 相似文献