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41.
The sequence of mitochondrial A6 (MURF4) was compared for several trypanosomatids in order to assess the reduction of the edited domain (ED). The association between the ED reduction and the phylogenetic position of a species proved to be less tight than believed earlier. Compared with digenetic species, monogenetic ones more often displayed ED reduction and had smaller ED.  相似文献   
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The dynamics of the ion temperature of the target plasma in a gas-dynamic trap during high-power neutral beam injection is measured by using the Rutherford scattering technique. A comparison of the experimental results with the results of simulations by a model based on the theory of pair Coulomb collisions indicates no significant anomalous losses from the ion plasma component.  相似文献   
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The single most difficult problem in phylogenetic analysis is deciding whether a shared taxonomic character is due to common ancestry or one that appeared independently due to convergence, parallelism, or reversion to an ancestral state. Mammalian L1 retrotransposons undergo periodic amplifications in which multiple copies of the elements are interspersed in the genome. Because these elements apparently are transmitted only by inheritance and are retained in the genome, a shared L1 amplification event can only be an inherited ancestral character. We propose that L1 amplification events can be an excellent tool for analyzing mammalian evolution and demonstrate here how we addressed several refractory problems in rodent systematics using L1 DNA as a taxonomic character.   相似文献   
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The investigation has been performed by means of the luminescent microscopical method. The retrograde axonal transport of the fluorescent marker primuline has demonstrated that a definite amount of labelled cells are observed in the celiac plexus, in nodes of the thoracic part of the sympathetic trunk (predominantly in Th6-Th8). Innervation of the EGP sphincter is mainly performed from the sympathetic trunk nodes (Th6-Th8) and from the celiac plexus.  相似文献   
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The authors describe electromyographic electrodes (EMG electrodes) for recording the activity of several muscles in chronic experiments on cats. An EMG electrode is a loop made of a silver wire 200 micron in diameter and 1.5-2 cm long, to which a flexible copper wire insulated with teflon 300 micron in diameter is soldered. The soldering site is insulated with biologically indifferent material. The EMG electrodes turned out fairly good in numerous experiments.  相似文献   
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Analysis of primary structure and organization of mitochondrial (kinetoplast) DNA of flagellates occupies a prominent place in the studies of eukaryote mitochondrial genomes, owing to its unusual organization and functioning as well as to the epidemiological role of the Trypanosomatidae family. According to contemporary notions, living zooflagellates are direct descendants of the ancestral forms that gave rise to all eukaryotic kingdoms. Hence, comparative mtDNA studies of recent Trypanosomatidae open broad prospects for phylogenetic reconstructions and analysis of presumable routes of eukaryote evolution. The structure, characteristics, and functions of Trypanosomatidae minicircular kinetoplast DNA are discussed here.  相似文献   
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