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31.
Radio-binding assay, bioassay and HPLC detection were used to observe the antagonistic effects of dextrorphan on PCP's actions. Dextrorphan displayed high affinity to PCP receptor in the rabbit mesenteric blood vessels. It had weak PCP-like bioactivity, but could antagonize PCP's action dose-dependently in vitro study with the rabbit ear artery preparation and shifted the dose-response curve of PCP to the right. After PCP administration, the content of norepinephrine in the vascular bath medium was increased, which was reversed by dextrorphan. Thus suggests that dextrorphan is an antagonist with very mild agonistic action for PCP receptors. 相似文献
32.
心不甘中甾体皂甙元的分离和结构鉴定(2) 总被引:2,自引:0,他引:2
自心不甘(Tupistra aurantiaca Wall et Backer)根的醋酸乙酯萃取物经硅胶柱层析分离除可得到1β、2β、3β、4β、5β、7α-hexahydroxyspirost-25(27)-en-6-one外,还得到7个游离的甾体皂甙元A—G,其中A及B分别为3-epiruscogenin及3-epi-neoruscogenin,F为△~(25(27))-pentrogenin(6)、C、D和E系新化合物,经IR、MS、~1H NMR及~(13)C NMR谱鉴定分别推定为ranmogenin A(3)、B(4)和C(5)(兰茂甙元甲、乙和丙)。 相似文献
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NAD-linked aldehyde dehydrogenase for aerobic utilization of L-fucose and L-rhamnose by Escherichia coli. 总被引:7,自引:6,他引:1 下载免费PDF全文
Mutant analysis revealed that complete utilization of L-fucose and L-rhamnose by Escherichia coli requires the activity of a common NAD-linked aldehyde dehydrogenase which converts L-lactaldehyde to L-lactate. Mutations affecting this activity mapped to the ald locus at min 31, well apart from the fuc genes (min 60) encoding the trunk pathway for L-fucose dissimilation (as well as L-1,2-propanediol oxidoreductase) and the rha genes (min 88) encoding the trunk pathway for L-rhamnose dissimilation. Mutants that grow on L-1,2-propanediol as a carbon and energy source also depend on the ald gene product for the conversion of L-lactaldehyde to L-lactate. 相似文献
35.
鲫鱼尾部神经分泌系统显微和亚显微结构的季节性变化 总被引:5,自引:0,他引:5
鲫鱼尾部神经分泌系统的神经分泌细胞和它的轴突中可观察到各种不同电子密度的颗粒。在性腺各个不同的发育阶段,该系统的分泌物具有累积、充满、释放和恢复这样一种周期性变化,由此说明鲫鱼的尾部神经分泌系统和它的生殖有关。 相似文献
36.
Q. L. Zhu 《Histochemistry and cell biology》1987,86(4):385-388
Summary The detection of fibronectin (FN) in osmium-fixed and Araldite-embedded frog skin fragments was studied using a modification of Baskin's procedure (Baskin et al. 1979). Following the removal of Araldite from the semi-thin sections (0.5–1.0 m) with ethanol-NaOH solution, the sections were bleached with hydrogen peroxide. FN was detected by indirect immunoperoxidase method. For precise localization of FN, careful attention was paid to the temperature, antibody concentrations and the quality of the ethanol-NaOH solution. Our results were in agreement with those that we had obtained previously for polyethylene glycol (PEG) sections, suggesting that the present procedure is useful for the detection of FN in Araldite-embedded biological specimens. 相似文献
37.
Sequence homology in the metalloproteins; purple acid phosphatase from beef spleen and uteroferrin from porcine uterus 总被引:1,自引:0,他引:1
D F Hunt J R Yates J Shabanowitz N Z Zhu T Zirino B A Averill S T Daurat-Larroque J G Shewale R M Roberts K Brew 《Biochemical and biophysical research communications》1987,144(3):1154-1160
The primary structures of purple acid phosphatase and uteroferrin, two iron-binding glycoproteins isolated from beef spleen and porcine uterine fluids, respectively, have been examined by a combination of tandem mass spectrometry and classical Edman sequencing methods. Reported here are amino acid sequence data covering more than 90% of the primary structures for these two proteins. The sequence data reveal an unexpectedly high degree of homology, greater than 90%, for these two proteins. 相似文献
38.
Submitochondrial particles were prepared from bovine heart mitochondria, solubilized with Triton X-114 in the presence of lipids and submitted to hydroxylapatite chromatography. The eluate obtained, containing a mixture of mitochondrial carriers, was processed further by affinity chromatography using as ligand p-aminophenylsuccinate coupled via a diazo bond to aminohexyl-Sepharose 4B. The activity of the dicarboxylate exchanger was measured after reconstitution into asolectin vesicles at each step of the purification procedure. All samples studied were found to display substrate and inhibitor specificity similar to those described for the dicarboxylate carrier in mitochondria. The specific activity of the final material eluted from the affinity column was found to be about 1000-times higher than that of the Triton X-114 extract of submitochondrial particles. SDS-polyacrylamide gel electrophoresis analysis of the affinity chromatography eluate showed the presence of only two polypeptides. 相似文献
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