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Bacillus subtilis transformation was conducted in the abdominal cavity of mice. The frequency of transformation was considerable decreased when bovine DNA-ase 1 (3-- 5microgram) was injected intraperitoneally to these animals. Immune rabbit gamma-globulins containing antibodies to bovine DNA-ase 1 inhibited in vivo the activity of DNA-ase 1, protected transforming DNA from the hydrolyzing effect of this enzyme. This model can be utilized in search for ways to preserve DNA injected into the animal organism for the purpose of genetical engineering.  相似文献   
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Abstrac  The composition of essential oil of Artemisia lerchiana Web. plants growing in Volgograd oblast was studied. Sampling was performed from plots contrasting in climatic and soil characteristics. Essential oil was obtained by hydrodistillation. The content of essential oil in shoot biomass increased gradually during shoot formation, flower bud formation, and flowering beginning and then decreased. The highest content of essential oil varied from 1.1 to 1.5% of plant dry weight at the stage of flower bud formation. More than thirty compounds were identified by gas chromatography-mass spectrometry. The following major components were found: camphor, borneol, bornylacetate, camphene, and 1,8-cineole. Some of compounds (sesquiterpenes and sesquiterpenoids) were identified for the first time. The time-course of accumulation of essential oil components strongly depended on habitat edaphic factors and climatic conditions during the year of sampling. The results permit a conclusion that A. lerchiana is a valuable producer of essential oils. Original Russian Text ? E.B. Kirichenko, Yu.V. Orlova, D.V. Kurilov, 2008, published in Fiziologiya Rastenii, 2008, Vol. 55, No. 6, pp. 934–941.  相似文献   
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Cyclic GMP-specific phosphodiesterase (3',5'-cyclic-nucleotide 5'-nucleotidohydrolase, EC 1.3.4.17) (PDE) is thought to be a key enzyme of the retinal-rod phototransduction cyclic nucleotide pathway. We attempted to investigate the properties and content of PDE in retinal-cone photoreceptors. The fractions obtained from cone-dominant ground squirrel retinas were analyzed for cone visual pigment content and PDE activity. The cone visual pigment content was estimated to be approx. 65 pmol per retina. The distribution of cone visual pigment coincided with that of the PDE activity through several steps of photoreceptor membrane purification by sucrose density gradient centrifugation. The ground squirrel retinal PDE was similar to the retinal-rod PDE by its kinetic properties, thermostability, sensitivity to tryptic activation, Stokes radius and pI values. The cone visual pigment enriched fractions contained the heat-stable trypsin-inactivated PDE inhibitor. Its functional properties seem to be similar to those of the retinal-rod PDE inhibitory subunit. The PDE content in ground squirrel retina was roughly estimated to be about five copies of enzyme per 100 cone visual pigment molecules. The obtained results indicated that the major portion of ground squirrel retinal cyclic GMP-specific PDE is the endogenous cone photoreceptor membrane enzyme and strongly supported the conception about the key role of PDE in cone phototransduction. The existence of essential differences between rod and cone systems rapidly returning cyclic GMP-specific amplification cascade components to the dark (or inactivated) states after photon absorption was suggested. If this suggestion is true, the well-known distinctions between response kinetics and light sensitivity of these two kinds of photoreceptor can be explained.  相似文献   
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The effects of chorionic gonadotropin, estriol (E3), leptin, ghrelin, and kisspeptin on the intracellular expression of perforin, granzyme A, and granzyme B was studied in separated NK cells. All studied hormones except E3 are could modulate the expression of cytotoxic enzymes in NK cells by suppression of the expression of the most active proapoptotic agents, resulting in increased expression of granzyme A, which is typical of the decidual subpopulation of these lymphocytes.  相似文献   
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The clinico-experimental studies of mixed influenza-staphylococcal infection constantly point to the development of the aggravation of the infectious process due to the synergic action of the bacterial and viral infective agents. But, as shown by the authors of the present work, in those cases when the experimental infection with the virus was preceded by staphylococcal infection by 72 hours no synergism was observed. In cases of infection with adaptogenic virus the mortality rate of mice resulting from meningococcal infection was twice as low. The possible explanation of this fact is discussed.  相似文献   
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