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71.
Anti-Candida activity of four antifungal benzothiazoles   总被引:1,自引:0,他引:1  
Abstract Anti- Candida activity of 6-amino-2- n -pentylthiobenzothiazole (I), benzylester of (6-amino-2-benzothiazolylthio)acetic acid (II) and of 3-butylthio-(1,2,4-triazolo)-2,3-benzothiazole (III) was followed and compared to that of 2-mercaptobenzothiazole (IV). I and II exhibited good activity against the C. albicans yeast form, similar to IV. They were inhibitorily active against other Candida strains, IC50 values being of the order of 10−5 M, which means better activity than IV. Compound I also exhibited inhibitory activity on germ-tube formation and mycelial growth in the C. albicans strains, while II, III and IV were not active in these tests. III was the least active form of the compounds tested, IC50 values being of the order of 10−4 M. All the compounds tested were highly active on a nystatin-resistant C. albicans mutant, with IC50s of the order of 10−6 M−10−5 M.  相似文献   
72.
We detected the presence of fructosamine in human and bovine semen. In seminal plasma of healthy normozoospermic men (N = 17) fructosamine was found in 53% of the cases (fru+). In fru+ semen samples the concentration of fructosamine was (mean +/- S.E.M., N = 9) 0.45 +/- 0.09 mmol/L and varied from 0.15 to 0.75 mmol/L. It was 3-12 times lower than in blood serum of healthy men. In semen of infertile men (N = 57) fructosamine was present only in 21% of the cases and its concentration was lower than in fertile men i.e. (mean +/- S.E.M., N = 12) 0.27 +/- 0.007 mmol/L. In bulls (N = 98) fructosamine was found in semen of 82% of animals. In fru+ semen samples the concentration of fructosamine was (mean +/- S.E.M., N = 80) 0.77 +/- 0.12 mmol/L and varied from 0.30 to 1.15 mmol/L. We did not find any correlation between the concentration of fructosamine on one hand, and that of fructose and glucose on the other hand, in either human or bull semen. The difference in the frequency of fructosamine appearance in semen of fertile and infertile men suggests that fructosamine may be in some way involved in the process of fertilisation.  相似文献   
73.
Cells from the L5178Y murine lymphoma subline LY-R are twice as resistent to killing by ionizing radiation than the subline LY-S. In contrast, LY-R cells are more sensitive to killing by H2O2, the effect being more pronounced at 37 °C than 0 °C. Initial DNA damage after H2O2 treatment (both temperatures, 5 min) has been estimated by the comet assay (single-cell gel electrophoresis) and fluorescent halo technique. According to both methods, the initial damage is significantly higher in LY-R cells, particularly that inflicted at O °C. Differences between DNA unwinding and rewinding abilities at pH 9 and 6.9 (estimated by the fluorescent halo technique) point to a considerable difference in pH-9-labile damage between the sublines, as observed previously for x-irradiated cells (Kapiszewska et al. 1992). In contrast to findings with x-irradiated cells, however, after H2O2 treatment this damage is more extensive in LY-R cells than in LY-S cells. Thus, the initial pH-9-labile damage corresponds to the pattern of sensitivity to H2O2 and x-rays. We suggest that this is caused by different proportions of cuprous and ferric ions found in the nuclei of LY sublines and by the different ability of these ions to react with H2O2 and water radiolysis products. The copper/iron ratio in the nucleus is 1.31 in LY-R cells and 4.84 in LY-S cells.  相似文献   
74.
In experiments on rabbits and dogs it was demonstrated that electrical stimulation of the centripetal fibres of the cut sciatic nerve causing a rise of the arterial blood pressure produced a significant increase in the plasma levels of adrenaline and noradrenaline. This effect was not observed in animals with sympathetic system blockade caused by administration of reserpine. These observations indicate that pressure increase after sciatic nerve stimulation is due to stimulation of the adrenergic system.  相似文献   
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Summary Familial occurrence of 1/21 translocation in connection with trisomy 21 was described. The possibilities of inheritance of further chromosome rearrangements arising during the gametogenesis of persons with this translocation were considered.  相似文献   
78.
Uterine responses to vasopressin and oxytocin were monitored in non-pregnant and 3- or 6-8-day-pregnant rabbits by recording the intrauterine pressure. Oxytocin stimulated uterine activity in all groups, but the effect of vasopressin was stimulatory in non-pregnant animals, inhibitory in those 3 days post coitum and weakly stimulatory in those later in pregnancy. Inhibition of prostaglandin (PG) synthesis, by the administration of indomethacin, reduced the spontaneous uterine activity as well as the responses to oxytocin and vasopressin in the non-pregnant rabbits, but had little effect in the pregnant animals. During infusion of PGF-2alpha, PGE-1 or PGE-2 in 6-8-day-pregnant rabbits, the stimulatory response to vasopressin, although slight before the infusion, was inhibited whereas the stimulatory response to oxytocin remained virtually unchanged. The results suggest that vasopressin and oxytocin under certain hormonal conditions, are able to activated the uterine contractions by mechanisms in which the involvement of PG is not obligatory.  相似文献   
79.
The pneumocytes of the larva of Salamandra salamandra contain numerous lamellar bodies and their precursors: electron-dense bodies at various stages of development. Both lamellar bodies and electron-dense bodies occur inside the fluid-filled lung. The former are spherical or bell-shaped and possess concentrically arranged smooth membranes, 8 nm thick; the latter have paracrystalline cores composed of alternately oriented clear and dark striations (3.6–3.9 nm and 2.6–3.6 nm, respectively). On all sides such cores separate membranes, which assume a concentric orientation. No tubular myelin was observed in any phase of the transformation of lamellar bodies and electron-dense bodies into the surface lining layer. Fixation of the lungs of adult individuals with tannic acid-containing fixative visualized the surface lining layer, but not tubular myelin.  相似文献   
80.
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