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The first comparison of mitochondrial variations in sables from captive and natural populations of the Urals, Central Siberia, Yakutia, Kamchatka, and Japan has been performed. The object of comparative analysis was a 427-bp 5' fragment of the mitochondrial control region, including the D-loop. Two main haplogroups of the sable mitochondrial genome have been found, which provides new data for reconstruction of the spread of the sable over its current range. Asymmetry of the haplotype abundances in the captive populations of sables has been detected. The mitochondrial haplotypes characteristic of sable breeds have been identified. The possible role of the frequent mitochondrial haplotypes of the captive population in the sable adaptation to the conditions of captivity is discussed.  相似文献   
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Peculiarities of the ultrastructure and RNA synthesis in the epithelial endometrial cells of nine patients with hyperplasia and the uterine cavity cancer have been studied by the electron-radioautographic method. Quantitative differences are revealed in the ultrastructures of the cells. Amplification of the nucleoli labelling and asynchronism of the RNA synthesis in the nucleoli with glandular hyperplasia and endometrial cancer are observed.  相似文献   
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Aquaporin 2 (AQP2) is a small, integral tetrameric plasma membrane protein that is expressed in mammalian kidneys. The specific constitution of this protein and its selective permeability to water means that AQP2 plays an important role in hypertonic urine production. Immunolocalization of AQP2 has been studied in humans, monkeys, sheep, dogs, rabbits, rats, mice and adult cattle. We analyzed the expression of AQP2 in kidneys of 7-month-old Polish-Friesian var. black and white male calves. AQP2 was localized in the principal cells of collecting ducts in medullary rays penetrating the renal cortex and in the collecting ducts of renal medulla. AQP2 was expressed most strongly in the apical plasma membrane, but expression was observed also in the intracellular vesicles and basolateral plasma membrane. Our study provides new information concerning the immunolocalization of AQP2 in calf kidneys.  相似文献   
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The Indian black berry (Syzygium cumini Skeels) has a great nutraceutical and medicinal properties. As in other fruit crops, the fruit characteristics are important attributes for differentiation were also determined for different accessions of S. cumini. The fruit weight, length, breadth, length: breadth ratio, pulp weight, pulp content, seed weight and pulp: seed ratio significantly varied in different accessions. Molecular characterization was carried out using PCR based RAPD technique. Out of 80 RAPD primers, only 18 primers produced stable polymorphisms that were used to examine the phylogenetic relationship. A sum of 207 loci were generated out of which 201 loci found polymorphic. The average genetic dissimilarity was 97 per cent among jamun accessions. The phylogenetic relationship was also determined by principal coordinates analysis (PCoA) that explained 46.95 per cent cumulative variance. The two-dimensional PCoA analysis showed grouping of the different accessions that were plotted into four sub-plots, representing clustering of accessions. The UPGMA (r = 0.967) and NJ (r = 0.987) dendrogram constructed based on the dissimilarity matrix revealed a good degree of fit with the cophenetic correlation value. The dendrogram grouped the accessions into three main clusters according to their eco-geographical regions which given useful insight into their phylogenetic relationships.  相似文献   
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Computer-aided search for novel anti-HIV-1 agents that are able to imitate the pharmacophore properties of the antigen-binding site of a broadly neutralizing mAb 3074 against the envelope gp120 V3 loop was carried out followed by evaluation of their potential inhibitory activity by molecular modeling. In doing so, the following problems were solved: (1) the mAb 3074 amino acid residues responsible for specific binding to the HIV-1 V3 loop were identified from the X-ray structures of this antibody Fab in complexes with the MN, UR29, and VI191 V3 peptides (Jiang et al., 2010); (2) using these data, 2039 possible mAb-3074 peptidomimetics were found by pepMMsMIMIC presenting a public, web-oriented virtual screening platform (Floris et al., 2011); (3) the complexes of these compounds with the above V3 peptides were built by molecular docking and, based on their analysis, the four molecules exhibiting a high affinity to V3 in the in silico studies were selected as the most probable peptidomimetics of mAb 3074 (Figure 1); and (4) stability of the complexes of these molecules with the MN, UR29, and VI191 V3 peptides was estimated by molecular dynamics and free energy simulations. As a result, a key role in specific binding of the selected compounds to the V3 loop was shown to belong to π-π interactions between their aromatic rings and the conserved Phe20 and/or Tyr21 of the V3 immunogenic crown. Similarly to mAb 3074, these compounds were found to block the tip of the V3 loop forming its invariant structural motif, which contains residues critical for cell tropism (Andrianov et al., 2011; Andrianov et al., 2012). In addition, the complexes of interest do not undergo significant changes within the molecular dynamics calculations, exhibiting the low values of free energy of their formation. In this context, the compounds given in Figure 1 are considered as the promising basic structures for the design of novel, potent, and broad anti-HIV-1 drugs.  相似文献   
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Russian Journal of Genetics - The harlequin ladybird Harmonia axyridis forms stable natural populations in East Asia and southern Siberia and spreading invasive populations in Europe, Africa, North...  相似文献   
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Using multiunit recording of action potentials from the whole vestibular nerve, we studied whether opioid peptide leu-enkephalin (Enk) may modulate muscarinic-like responses in semicircular organs of the frog. When acetylcholine (ACh) (0.1-1 mM) was applied with 1 nM Enk, the maximal frequency increase induced by ACh was reduced.However,the frequency decrease of ACh responses under Enk did not differ from the frequency decline in basal spike discharge induced by Enk alone. Administration of atropine (1 microM) left the response to Enk intact and blocked the excitatory effect of ACh. No modification of the ACh response under Enk was observed in the presence of the non-selective opioid receptor antagonist naloxone (10 microM). This study suggests that no interaction exists between the ACh-mediated excitatory action on resting activity in the isolated semicircular canal preparation and the suppressive action of Enk.  相似文献   
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