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1.
The pleiotropic effects of transgenesis includes different consequences of the insertion of a transgene that are not related to the direct action of its product. It is necessary to evaluate the outlook for the application in selection of the transgenic potato strain containing the bacterial chitinase gene chiA we created for studying the possible nonspecific influence of the introduction of the transgene on the phenotypical properties of the transgenic lines. In the present investigation we will consider the effect of the introduction of the chitinase transgene on such agronomically important characteristics as yield and nonspecific resistance.  相似文献   
2.
In several geographic populations of the Arctic ground squirrel C. parryi, studies have been made on changes in oxygen consumption during decrease of the ambient temperature from 25 to 3-4 degrees, thermal preference, hemoglobin content of the blood and composition of the adipose tissue (both brown and white, subcutaneous and visceral). Significant shifts of these indices were found. In animals from various parts of the species area, different sensitivity to cooling was found, as indicated by determinations of oxygen consumption at different temperatures and the prefered temperature: different hemoglobin content of the blood was also found together with differences in the level of two unsaturated fatty acids - the oleic and linoleic ones. Comparison of these data with similar results obtained on various populations of the Siberian ground squirrel C. undulatus revealed obvious differences between these close species with respect to the indices studied.  相似文献   
3.
Study of development of early forms of behaviour was carried out on intact kittens of the first month of life, who endured in 5 days age uni- and bilateral sections of the lingual nerve, and on shame-operated and undernourished animals. It was shown that bilateral deafferentation caused significant disturbance of alimentary behaviour at the stage of sucking, manifested in disturbance of natural sucking and appearance of shame sucking, i.e. rhythmic sucking movement without nipple grasping. At the one-month age, in conditions of artificial feeding, natural sucking in operated animals was restored and the shame one disappeared. Bilateral section of the lingual nerve led to acceleration of ripening of sensory and motor systems and accelerated development of homing, exploratory and playing behaviour. Possible role is discussed of sensory trigeminal nuclei neurones in organization of normal patterned sucking and at limited sensory inflow. It is suggested that elimination of sensory input developing in the norm earlier than others, changes natural terms of other channels development, what accelerates the change of early behaviour forms.  相似文献   
4.
The influence of Mn on saturation curves of ESR spectra of Ph(-) and P(+)(680) at 1-200K in samples with different content of Mn has been studied. An analysis of these data and those on photoinduced changes of fluorescence yield of chlorophyll leads to the conclusion that the Mn-containing centre in Photosystem 2 is a cluster of 4 Mn atoms, two of which can be replaced by Mg(2+) or any other divalent metal. The distances between Mn Na Ph as well as between Mn and P(680) have been estimated.  相似文献   
5.
The effect of neurotensin on submaximally-stimulated hepatobiliary and pancreatic secretion was studied in 6 healthy subjects. An intravenous infusion of neurotensin 1.4 ± 0.3 pmol/kg/min, designed to reproduce plasma neurotensin immunoreactivity levels within the physiological range, produced a significant increase in pancreatic bicarbonate output. Plasma concentrations of pancreatic polypeptide rose by 83 ± 16 pmol/l and were associated with a small reduction in trypsin, but no significant change in bilirubin outputs.  相似文献   
6.
The effect of palladium and platinum salts (K2PdCl4, K2PtCl4) on bacteriophage F4 and its isolated DNA in genetic transformation is investigated. Both compounds efficiently inactivated the phage and decreased the transforming activity of donor DNA. The palladium salt exhibited the higher activity. The palladium compounds inhibited the transforming activity of native donor DNA to a greater degree. No difference was observed in the degree of inactivation of the transforming activity of native and denatured DNA under the effect of platinum salt. It is suggested that the difference in the transforming activity of donor DNA treated with the tested compounds reflect the pattern of their interactions with nucleic acids.  相似文献   
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A large-scale study of short retroposon (SINE) B1 has been conducted in the genome of rodents from most of the known families of this mammalian order. The B1 nucleotide sequences of rodents from different families exhibited a number of characteristic features including substitutions, deletions, and tandem duplications. Comparing the distribution of these features among the rodent families, the currently discussed phylogenetic relationships were tested. The results of analysis indicated (1) an early divergence of Sciuridae and related families (Aplodontidae and Gliridae) from the other rodents; (2) a possible subsequent divergence of beavers (Castoridae); (3) a monophyletic origin of the group Hystricognathi, which includes several families, such as porcupines (Hystricidae) and guinea pigs (Caviidae); (4) a possible monophyletic origin of the group formed by the remaining families, including six families of mouselike rodents (Myodonta). Various approaches to the use of short retroposons for phylogenetic studies are discussed.  相似文献   
10.
DNA samples of unrelated subjects from the Volga-Ural region of Russia were examined to study allele polymorphism of the pentanucleotide repeat (TTGTG)8 localized to an intron of the tumor suppressor gene ING1. STR marker was registered in the EMBL database with the accession number AJ277387. In a sample of 119 individuals, three pentanucleotide alleles consisting of seven, eight, and nine repeated monomers were revealed. The allele frequencies were 0.24, 0.74, and 0.02, respectively. Heterozygosity was 0.45. On the basis of these data, the repeat can be regarded as a polymorphic STR marker for the ING1 gene and used in population and clinical studies.  相似文献   
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