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101.
The incubation of pea seedling roots with the surface agglutinins R1 and R2 of Rhizobium leguminosarum 252 brought about an increase in the activity of proteases, beta-glucosidase, and, especially, succinate dehydrogenase in the roots. The data presented show that rhizobial agglutinins play an important part in the formation and functioning of legume-rhizobial associations. 相似文献
102.
目的:观察原儿茶酸对鱼藤酮诱导的帕金森模型小鼠脑组织中相关抗氧化酶活性的影响,为原儿茶酸治疗帕金森病提供理论依据。方法:选用昆明小鼠为实验动物,连续5周腹腔注射鱼藤酮(1mg/kg.d)建立帕金森模型,之后2周分别注射原儿茶酸(5mg/kg.d)和阳性药物美多芭(125mg/kg.d)。应用生物化学方法,观察原儿茶酸对帕金森模型小鼠中脑和纹状体内超氧化物歧化酶(SOD)、过氧化氢酶(CAT)、谷胱甘肽过氧化物酶(GSH-PX)活力以及脂质过氧化物丙二醛(MDA)含量的影响。结果:实验数据显示原儿茶酸可提高帕金森模型小鼠中脑和纹状体SOD、CAT、GSH-PX活力,降低MDA含量。同时病理切片染色显示原儿茶酸可减轻鱼藤酮诱导的脑组织损伤。结论:原儿茶酸具有神经保护作用,保护机制可能是提高脑组织内源性抗氧化酶活力,减少体内自由基的产生,进而减轻了脑组织的病理损伤。 相似文献
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Steroid hormones play critical roles in almost all physiological processes in male and female reproduction. In a normal pregnancy, the concentrations of steroid hormones in maternal and foetal blood vary with gestation in response to changing needs. The placenta plays a central role in producing the appropriate steroids to support the pregnancy by coordinating its own steroidogenic activity with that of the corpus luteum and responding to foetal signals. Although much is known about the steroidogenic potential of the bovine placenta, far less is known about how the placenta integrates the synthesis of steroids with their subsequent metabolism and clearance to achieve appropriate local and peripheral concentrations of steroids in maternal and foetal blood at each stage of gestation. This review focuses on the current knowledge of the temporal and spatial regulation and compartmentalization of the biochemical pathways by which potent steroid hormones are synthesized and metabolized in the bovine placenta. The aim is to increase our understanding of how the balance of synthesis and metabolism determines placental steroid output as it changes with development and differentiation, and how this is regulated in response to the variations in the foetal signals and luteal secretory activity. The review highlights knowledge gaps and suggests that mathematical modelling can help understand the effect of different levels of regulation on the steroidogenic output of an organ, such as the bovine placenta. 相似文献
105.
A. P. Bonartsev S. G. Yakovlev E. V. Filatova G. M. Soboleva T. K. Makhina G. A. Bonartseva K. V. Shaitan V. O. Popov M. P. Kirpichnikov 《Biochemistry (Moscow) Supplemental Series B: Biomedical Chemistry》2012,6(1):42-47
The development of sustained release formulations based on biodegradable polymers is a promising trend in modern pharmacology.
Polyhydroxyalkanoates (PHA) attract increasing attention due to their biodegradability and high biocompatibility, which make
them suitable for the development of novel drug dosage forms. We have produced poly(3-hydroxybutyrate) (PHB)-based microspheres
loaded with the antitumor drug paclitaxel and investigated morphology, drug release kinetics and the effect of these microspheres
on tumor cells in vitro. The data on the kinetics of drug release, biocompatibility and biological activity of the biopolymer
microspheres in vitro have demonstrated that the studied system of prolonged drug release had lower toxicity and higher efficiency
compared to the traditional dosage forms of paclitaxel. 相似文献
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SIEMON H. S. NG ALAN CHANG GORDON D. BROWN BEN F. KOOP WILLIAM S. DAVIDSON 《Molecular ecology resources》2005,5(4):762-766
The detection of simple sequence repeats (SSRs) within expressed sequence tags (ESTs) connects potential microsatellite markers with specific genes, generating Type I markers. Using an in silico approach, we identified 1975 SSRs from the Genome Research on Atlantic Salmon Project EST database. We designed primers to amplify 158 SSRs, of which 65 amplified 76 loci (including 11 duplicated loci). Sixty‐one of the 76 loci were variable in 24 Atlantic salmon from seven populations, and 96% of these markers also amplify DNA from other salmonids. Functions for 16 of the SSR associated ESTs have been determined, confirming them as Type I markers. 相似文献
110.
Polymorphism of genes of the antioxidant system in the development of predispositions to lung cancer
R. A. Titov V. I. Minina O. A. Soboleva A. V. Ryzhkova Yu. E. Kulemin E. N. Voronina 《Russian Journal of Genetics》2017,53(8):903-909
We analyzed the polymorphic loci in the genes of the antioxidant system enzymes, such as GSTP1 (313A>G and 341C>T), MnSOD (47С>Т), GPx1 (599C>T), and CAT (–262C>>T), among 497 residents of Kemerovo oblast (Western Siberia, Russia). The analysis of the single-locus effects demonstrated a significant protective effect of the major C allele in the GPx1 (599C>T) locus. The MDR analysis of the gene-gene interactions showed that the GPx1 and the CAT genes work in close cooperation and mutually reinforce the risk of development of squamous cell lung cancer among the inhabitants of the industrial region. 相似文献