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51.
Deniz EKİNCİ 《Journal of enzyme inhibition and medicinal chemistry》2013,28(4):1034-1039
The in vitro effects of the analgesic drugs, lornoxicam, indomethacin, tenoxicam, diclofenac sodium, ketoprofen and lincomycine, on the activity of purified human serum paraoxonase (hPON1) (EC 3.1.8.1.) were evaluated. hPON1 was purified from human serum with a final specific activity of 3840 U mg?1 and a purity of 25.3 % using simple chromatographic methods, including DEAE-Sephadex anion exchange and Sepharose 4B-L-tyrozine-1-napthylamine hydrophobic interaction chromatography. SDS-polyacrylamide gel electrophoresis indicated a single protein band corresponding to hPON1. The six analgesics dose-dependently decreased in vitro hPON1 activity, with IC50 values for lornoxicam, indomethacin, tenoxicam, diclofenac sodium, ketoprofen and lincomycine of 0.136, 0.195, 0.340, 1.639, 6.23 and 9.638 mM, respectively. Ki constants were 0.009, 0.097, 0.306, 0.805, 13.010 and 11.116 mM, respectively. Analgesics showed different inhibition mechanisms: lornoxicam, diclofenac sodium and lincomycine were uncompetitive, indomethacin and tenoxicam were competitive, ketoprofen was noncompetitive. According to the results, inhibition potency was lornoxicam>indomethacin>tenoxicam> diclofenac sodium>ketoprofen> lincomycine. 相似文献
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INTRODUCTIONRecombinant DNA technology is a powerful toolfor the introduction of foreign genes into longlivedperennials and fOr fundamelltal studies of gene expression. Using such techniques, we can overcomethe difficulties associated with the breeding of a long-lived perennial. At present, although considerablereseaxch effort has been devoted to the genetic en-gineering of fOrest trees, it has lagged behind ad-vances made in herbaceous crops due both to eco-nomics and the recalcitrant n… 相似文献
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A likelihood method for the detection of selection and recombination using nucleotide sequences 总被引:28,自引:12,他引:16
Different regions along nucleotide sequences are often subject to different
evolutionary forces. Recombination will result in regions having different
evolutionary histories, while selection can cause regions to evolve at
different rates. This paper presents a statistical method based on
likelihood for detecting such processes by identifying the regions which do
not fit with a single phylogenetic topology and nucleotide substitution
process along the entire sequence. Subsequent reanalysis of these anomalous
regions may then be possible. The method is tested using simulations, and
its application is demonstrated using the primate psi eta-globin
pseudogene, the V3 region of the envelope gene of HIV-1, and argF sequences
from Neisseria bacteria. Reanalysis of anomalous regions is shown to reveal
possible immune selection in HIV-1 and recombination in Neisseria. A
computer program which implements the method is available.
相似文献
56.
N. C. Stickland 《Biotechnic & histochemistry》1975,50(4):255-264
Nine different fixatives (Carnoy's, Susa, Baker's formalin, 5% formalin, 10% formalin, 10% formol saline, Bouin, Zenker, and 2.5% glutaraldehyde) were compared by two methods. Gelatin-albumin gels were used to study volum changes after fixation and after various stages of subsequent processing. The appearance and hardness of the gels were also noted. The fixatives either shrunk or swelled the gels, but dehydration and clearing shrunk the gels in all cases. Sampkes of muscle tissue from one location in beef longissimus dorsi muscle were also placed in the different fixatives and processed. Various features were noted for each fixative, including the ease with which the paraffin wax blocks were cut and the staining ability of the sections in Mallory's triple stain. The diameters of the muscle fibers were measured from transverse sections of these samples and compared with the mean diameter of muscle fibera in a frozen unfixed section of muscle tissue. It was found that the fixatives had the same shrinkage effects on both the gels and the muscle samples. Analysis of variance tests showed that the various fuatives caused different degrees of shrinkage. Statistical details are given for the amounts of shrinkage caused by each fixative. Both the general histological picture and the amount of shrinkage were considered when deciding the bcst fixative. Carnoy was found to be the best of the fixatives investigated. 相似文献
57.
C M Dwyer A J Madgwick A R Crook N C Stickland 《Journal of developmental physiology》1992,18(6):295-302
Fetal growth is known to be correlated with the size of the placenta and the exchange surface area. Reduction in the growth of the materno-fetal exchange surface areas may be a mechanism by which the effects of maternal undernutrition on fetal growth are mediated. In the compact placenta of the guinea pig the exchange surface is equivalent to the peripheral labyrinth. The effect of a 40% reduction in maternal feed intake on the growth of the peripheral labyrinth was investigated in pregnant guinea pigs between gestational days 25 and 65. Fetal and placental weights were significantly reduced in the last trimester by 32% and 38% respectively (P < 0.01). Placental efficiency in early gestation was significantly impaired in restricted animals but equivalent to ad lib. fed controls by the last trimester. The volume of the peripheral labyrinth increased as a percentage of the total placental volume with gestational age. Restricted placentae tended to be composed of a smaller volume of peripheral labyrinth tissue in early gestation. It is suggested that maternal undernutrition results in an impaired or delayed expansion of the peripheral labyrinth in early gestation causing a reduction in placental efficiency. By the last trimester the weight of the peripheral labyrinth of restricted animals was reduced by 33% (P < 0.05). The weight of the peripheral labyrinth was also significantly correlated with fetal weight is limited by the size of the peripheral labyrinth in the later stages of gestation. 相似文献
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Induced pluripotent stem(iPS) cells can be derived from human somatic cells by cellular reprogramming.This technology provides a potential source of non-controversial therapeutic cells for tissue repair,drug discovery,and opportunities for studying the molecular basis of human disease.Normally,mouse embryonic fibroblasts(MEFs) are used as feeder layers in the initial derivation of iPS lines.The purpose of this study was to determine whether SNL fibroblasts can be used to support the growth of human iPS cell... 相似文献