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161.
The effect of substance P on alcohol intake was studied in rats using a limited scheduled access paradigm. Ascending doses of substance P (100 and 200 micrograms/kg) were administered intraperitoneally to rats approximately 30 minute prior to their 1-hour-per-day access to alcohol. Each dose was administered for 3 successive days, and the effect of substance P was compared to that of saline solution control. Substance P at the dose of 100 micrograms/kg had no effect on alcohol consumption but significantly decreased the alcohol intake at the dose of 200 micrograms/kg. Thus, substance P reduces the alcohol motivation of rats in a limited scheduled access paradigm.  相似文献   
162.
One of the evolutionary mechanisms for acquisition of novel functional sequences can be domestication of exogenous retroviruses that have been integrated into the germ line. The whole genome mapping of such elements in various species could reveal differences in positions of the retroviral integration and suggest possible roles of these differences in speciation. Here, we describe the number, locations and sequence features of the human endogenous retrovirus HERV-K (HML-2) long terminal repeat (LTR) sequences on human chromosome 21. We show that their distribution along the chromosome is not only non-random but also roughly correlated with the gene density. Amplification of orthologous LTR sites from a number of primate genomes produced patterns of presence and absence for each LTR sequence and allowed determination of the phylogenetic ages and evolutionary order of appearance of individual LTRs. The identity level and phylogenetic age of the LTRs did not correlate with their map locations. Thus, despite the non-random distribution of LTRs, they have apparently been inserted randomly into the chromosome relative to each other. As evidenced in previous studies of chromosomes 19 and 22, this is a characteristic of HERV-K integration.  相似文献   
163.
The effects of transformation of downy birch (Betula pubescens Ehrh.) with the GS1 gene encoding the cytosolic form of glutamine synthetase on the rooting of plants in vitro was studied. The transgenic plants had an elevated content of glutamine as well as glutamic and aspartic acids and rooted more rapidly than the control plants. Rooting on a medium containing the glutamine synthetase inhibitor phosphinothricin prevented the accumulation of auxin in birch plants carrying the GS1 gene, indicating the involvement of this enzyme in raising the level of auxins in the transgenic plants. The correlation between the increase in the auxin levels in the transgenic plants carrying the glutamine synthetase gene and the increase in the rooting rate is shown for the first time.  相似文献   
164.
The iron(II) clathrochelates with apical adamantyl substituents were synthesized by the direct template reaction on a metal ion matrix. The nucleophilic substitutions of reactive hexachloride precursors with adamantylthiolate anion afforded hexa- and octaadamantyl cage iron(II) complexes. Clathrochelates obtained have been characterized using elemental analysis, MALDI-TOF mass, IR, UV-Vis, 57Fe Mössbauer and 1H, 13C NMR spectroscopies, and X-ray crystallography. Configurations intermediate between trigonal prismatic and trigonal antiprismatic have been deduced for the low-spin iron(II) ion coordination polyhedra of all clathrochelates obtained using 57Fe Mössbauer parameters and confirmed by X-ray crystallography data. Two apical and up to six ribbed adamantyl substituents allow one to change the physical properties of clathrochelates synthesized in wide range. In particular, these substituents form second (hydrophobic) shell that opens up the possibility to membrane and cellular transport of the cage complexes.  相似文献   
165.
The data on 31–37 allozyme loci in 21 species of nine salmonid genera are used for phylogenetic analysis by seven distance methods and several variants of cladistic analysis. Monophyletic origin for all genera and three sub-families of the Salmonidae is corroborated. The closest phylogenetic relationships are characteristic of Parasalmo and Oncorhynchus (bootstrap support is 88–99%), Brachymystax and Hucho (68–97%), and the clade ( Brachymystax + Hucho )+ Salmo (up to 85%). The patterns of phylogenetic relationships in the group Salmo-Parasalmo-Oncorhynchus are analogous to those in the group Parahucho-Hucho-Brachymystax. The position of Parahucho in phylogenetic trees of the Salmoninae is extremely unstable, although it is most likely associated with the clade ( Brachymystax + Hucho)+Salmo ) or Salvelinus. When using the out group analysis, Salvelinus appears as the earliest branch of the Salmoninae tree, whereas if the molecular clock is assumed, the basal position is occupied by Oncorhynchus. However, the latter genus is probably characterized by a substantially increased rate of molecular evolution.  相似文献   
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