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991.
992.
G. V. Smirnova G. I. Vysochina N. G. Muzyka Z. Yu. Samoilova T. A. Kukushkina O. N. Oktyabr’ski 《Applied Biochemistry and Microbiology》2009,45(6):638-641
An antioxidant activity of the water-alcohol extracts of leaves of ten herbs from Western Siberia was studied. In vivo the
capability of extracts to protect cells of Escherichia coli against the bacteriostatic action of H 2O2 and the influence of the extracts on the expression of the antioxidant gene katG coding catalase-hydroperoxidase I were investigated. In vitro the radical-binding activity with DPhPG· (1,1-diphenyl-2-picrylhydrazyl radical), the chelating capability with ferrozine, and total composition of flavonoids and
tannins were determined. The extracts of Filipendula stepposa and Limonium gmelinii were characterized by the highest antioxidant activity. According to data, the test extracts could have an antioxidant effect
on bacteria in different ways at once including the direct inhibition of ROS (reactive oxygen species), iron ion chelation
and antioxidant gene induction. 相似文献
993.
994.
Staining and histochemical methods, immunofluorescence, and electron microscopy were used to individualize the prolactin cells in the adenohypophyseal pars distalis of the nonhibernating hedgehog. One cell type was differentiated; their characteristics at the light and electron microscopic levels were presented. Immunofluorescence has confirmed the functional significance of this cell type and the validity of the denomination 'prolactin cells'. 相似文献
995.
The review analyzes structure-activity relations among dermorphin analogues. Dermorphin (Tyr-D-Ala-Phe-Gly-Tyr-Pro-Ser-NH2) is one of natural opioid peptides having a unique structure and exerting a very potent and prolonged antinociceptive effect. Methods of dermorphin synthesis are summarized together with data on more than 300 dermorphin-like peptides: the physico-chemical characteristics and data on opioid tests in vitro and in vivo are discussed. Based on these studies, conclusions have been drawn on the functional role of each amino acid residue in the dermorphin molecule and on modifications leading to analogues with high and differential opioid activity. 相似文献
996.
Jake V Bailey Verena Salman Gregory W Rouse Heide N Schulz-Vogt Lisa A Levin Victoria J Orphan 《The ISME journal》2011,5(12):1926-1935
We present evidence for a dimorphic life cycle in the vacuolate sulfide-oxidizing bacteria that appears to involve the attachment of a spherical Thiomargarita-like cell to the exteriors of invertebrate integuments and other benthic substrates at methane seeps. The attached cell elongates to produce a stalk-like form before budding off spherical daughter cells resembling free-living Thiomargarita that are abundant in surrounding sulfidic seep sediments. The relationship between the attached parent cell and free-living daughter cell is reminiscent of the dimorphic life modes of the prosthecate Alphaproteobacteria, but on a grand scale, with individual elongate cells reaching nearly a millimeter in length. Abundant growth of attached Thiomargarita-like bacteria on the integuments of gastropods and other seep fauna provides not only a novel ecological niche for these giant bacteria, but also for animals that may benefit from epibiont colonization. 相似文献
997.
The influence of Rms163 plasmid on lysogenization of Pseudomonas aeruginosa cells by B39 phage was studied. Plasmid Rms163 was shown to increase the frequency of lysogenization of PAO1 cells 7-8 times. C-mutants of B39 phage were isolated. According to complementation test, c-mutants were distributed into two groups--cI and cII/III. The product of cI is essential for establishment and maintenance of lysogenic state, cII/cIII product being only necessary for establishment of lysogenization. The mutants with special characteristics were isolated: B39cx1 phage carries a mutation which seems to be located on a regulatory site essential for establishment of lysogenic state. The region of the B39 genome responsible for interaction with Rms163 plasmid was mapped. Possible mechanisms of Rms163 plasmid interference with transposable B39 phage are discussed. 相似文献
998.
999.
Errors Related to Different Techniques of Intraperitoneal Injection in Mice 总被引:1,自引:0,他引:1 下载免费PDF全文
We found a 12% error in the placement of intraperitoneal injections of mice with the one-man procedure of injection. With a two-man procedure, the incidence of error was consistently reduced to 1.2%. 相似文献
1000.