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11.
L. A. Fomenko E. A. Kuznetsova A. I. Gaziev 《Radiation and environmental biophysics》1984,23(3):223-233
Summary The effect of mercaptoethylamine (MEA) on degradation of DNA in thermophilic bacteria Bac. stear. exposed to-, UV-rays or methylnitrosourea (MNU) was studied. Using centrifugation on alkaline and neutral sucrose gradients, it was shown that MEA inhibits the accumulation of breaks in the DNA of Bac. stear. It also lowers the level of DNA degradation in toluene-treated cells of Bac. stear. under the action of the intrinsic nuclease, reduces the activity of the endonuclease specific for apurinic DNA, as well as that of S1-nuclease and DNase-I in vitro. The inhibition in the accumulation of DNA breaks is assumed to be due to a decrease of the endonuclease activity in the cells of thermophilic bacteria. 相似文献
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I P Ashmarin M F Obukhova A A Mart'ianov R A Danilova N E Babskaia Z I Storozheva G K Grechko N V Kuznetsova 《Nauchnye doklady vysshe? shkoly. Biologicheskie nauki》1991,(3):15-24
The active immunization of rabbits and white rats to antidepressant sydnophen results in the formation of antibodies binding norepinephrine, dophamine, serotonine as well peptide regulatory compounds: substance P, pynorphine, vasopressin and beta-endorphin. The immunization against endogenic antidepressant thyroliberin induces the formation of antibodies to the same biogenic amines and to the gamma-aminobutyric acid, oxytocin and leu encephalin. The data obtained are discussed in connection with some physiological and biochemical changes found earlier during immunization to antidepressants. 相似文献
13.
Multiple enzymic lesions in obligate methanotrophic bacteria 总被引:1,自引:0,他引:1
14.
Ecological genetics of Italian peach‐potato aphid (Myzus persicae) populations in relation to geography,dispersal and insecticide resistance as studied using microsatellite and resistance markers 下载免费PDF全文
Valentina Monti Hugh D. Loxdale Michele Cesari Milo Frattini Michela Panini Emanuele Mazzoni Gian Carlo Manicardi 《Agricultural and Forest Entomology》2016,18(4):376-389
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15.
Valentina Degasperi Fabio Gasparini Sebastian M Shimeld Chiara Sinigaglia Paolo Burighel Lucia Manni 《BMC developmental biology》2009,9(1):48
Background
Ascidians are tunicates, the taxon recently proposed as sister group to the vertebrates. They possess a chordate-like swimming larva, which metamorphoses into a sessile adult. Several ascidian species form colonies of clonal individuals by asexual reproduction. During their life cycle, ascidians present three muscle types: striated in larval tail, striated in the heart, and unstriated in the adult body-wall. 相似文献16.
T. V. Kuznetsova G. V. Sladkova S. V. Kholodkevich 《Journal of Evolutionary Biochemistry and Physiology》2010,46(3):241-250
The work deals with study of basic characteristics of cardiac activity (heart rate—HR and stress-index—SI) and hemolymph protein
parameters in the crayfish Pontastacus leptodactylus. The main criteria of the crayfish selection are developed for formation of the animal reference groups available for subsequent
toxicological experiments. The action of a model toxicant, hydroquinone (often present in waste water), at a concentration
of 1 g/l on parameters of the crayfish cardiac activity at various exposition time, its effect on circadian cardioactivity
and on the hemolymph total protein were studied. At its short-term action, hydroquinone produced a temporary increase of HR
and stress-index, but had no marked effect on total protein parameters in hemolymph. At long action (for one day), hydroquinone
led to a considerable tachycardia, disturbance of the circadian cardioactivity and to a decrease by 40% of the hemolymph total
protein. In 50% of cases the toxicant caused death of the animals either in the course of its short-term action or at period
of washout from the toxicant. Mechanisms of the toxic action of hydroquinone at various levels of organization are discussed. 相似文献
17.
Augello C Gregorio V Bazan V Cammareri P Agnese V Cascio S Corsale S Calò V Gullo A Passantino R Gargano G Bruno L Rinaldi G Morello V Gerbino A Tomasino RM Macaluso M Surmacz E Russo A 《Journal of cellular physiology》2006,207(3):654-659
The putative role of TP53 and p16(INK4A) tumor suppressor genes and Ras oncogenes in the development and progression of salivary gland neoplasias was studied in 28 cases of pleomorphic adenomas (PA), 4 cases of cystic adenocarcinomas, and 1 case of carcinoma ex-PA. Genetic and epigenetic alterations in the above genes were analyzed by Polymerase Chain Reaction/Single Strand Conformational Polymorphism (PCR/SSCP) and sequencing and by Methylation Specific-PCR (MS-PCR). Mutations in TP53 were found in 14% (4/28) of PAs and in 60% (3/5) of carcinomas. Mutations in H-Ras and K-Ras were identified in 4% (1/28) and 7% (2/28) of PAs, respectively. Only 20% (1/5) of carcinomas screened displayed mutations in K-Ras. p16(INK4A) promoter hypermethylation was found in 14% (4/28) of PAs and 100% (5/5) carcinomas. All genetic and epigenetic alterations were detected exclusively in the epithelial and transitional tumor components, and were absent in the mesenchymal parts. Our analysis suggests that TP53 mutations and p16(INK4A) promoter methylation, but not alterations in the H-Ras and K-Ras genes, might be involved in the malignant progression of PA into carcinoma. 相似文献
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Radice F Orlandi V Massa V Battini V Bertoni G Reineke W Barbieri P 《Applied microbiology and biotechnology》2007,75(5):1111-1118
An Arthrobacter strain, able to utilize 4-chlorobenzoic acid as the sole carbon and energy source, was isolated and characterized. The first step of the catabolic pathway was found to proceed via a hydrolytic dehalogenation that leads to the formation of 4-hydroxybenzoic acid. The dehalogenase encoding genes (fcb) were sequenced and found highly homologous to and organized as those of other 4-chlorobenzoic acid degrading Arthrobacter strains. The fcb genes were cloned and successfully expressed in the heterologous host Pseudomonas putida PaW340 and P. putida KT2442 upper TOL, which acquired the ability to grow on 4-chlorobenzoic acid and 4-chlorotoluene, respectively. The cloned dehalogenase displayed a high specificity for para-substituted haloaromatics with affinity Cl > Br > I > F, in the order. 相似文献