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21.
Following is the first publication of a previously unknown translation by L.S. Vygotsky from Hebrew of a fictional short story by M.J. Berdyczewski, a Jewish writer popular at the beginning of the twentieth century. The commentary by the authors of this article reconstructs the context of Vygotsky’s life situation during the prerevolutionary period. Particular attention is focused on the questions of ethnic and cultural self-determination that were confronting him. The cultural contexts essential for an understanding and interpretation of the artistic and world-view features of the text of the short story are explored. A comparison is drawn to show the connection between the themes addressed in the story and the substantive problems that Vygotsky would subsequently deal with as a professional psychology: the artistic inner experience, moral choice, and cultural mediation.  相似文献   
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Physiological, biochemical and histological indices in Clarias gariepinus broodstock, and teratogenic indices in embryos exposed to sublethal concentrations of naphthalene, phenanthrene and pyrene were investigated in 2014 using a static-renewal bioassay protocol. Phenanthrene (1.41 mg l?1) was the most toxic, followed by pyrene (1.53 mg l?1) and naphthalene (7.21 mg l?1), based on 96 h LC50 values. Hepatosomatic indices were significantly higher in naphthalene- and pyrene-treated males compared with solvent controls, whereas fecundity in females was significantly lower by factors of 2.4 (naphthalene), 2.8 (phenanthrene) and 2.4 (pyrene), compared with controls. Catalase levels were lower in female phenanthrene-treated fish compared with controls. Histological alterations observed in PAH-treated fish include oedema, inflammatory cells, epithelial lifting and hyperplasia in the gills, vacuolation, haemosiderin pigments and sinusoidal congestion in the liver, and degenerated zona radiata in the ovary. Teratogenic effects were not observed, as evidenced by the lack of histological alterations in embryos spawned from pre-exposed broodstock. Sex-specific responses and the utility of biomarkers at cellular and individual levels of organisation are therefore demonstrated for holistic evaluations of polycyclic aromatic hydrocarbons in ecotoxicological studies.  相似文献   
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Biomarkers of oxidative stress such as catalase (CAT), glutathione S-transferase (GST), glutathione reductase (GR) activity, and malondialdehyde and reduced glutathione content, as well as heavy metal concentrations (HM: Pb, V, Cr, Mn, Co, Ni, Cu, Zn, and Cd), were studied in Dreissena polymorpha tissues. Mussels were collected on three sites located on the Rybinskoe Reservoir different in levels of anthropogenic pressure: the most polluted sites were 1 and 2 and site 3 was relatively clean. Mussels from sites 1 and 2 had higher concentrations of HM (Pb, V, Cr, Mn, Ni, Cu, and Mn) and their response to the pollutant action was manifested in increased processes of lipid peroxidation (LPO), the activation of CAT, and elevated level of GHS.  相似文献   
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The adjuvant activity in DNA immunization against herpes simplex virus type 1 (HSV1) was studied for the granulocyte-macrophage colony-stimulating factor (GM-CSF) synthesized from an eukaryotic expression plasmid (pDNAGM-CSF) and for the synthetic glucosaminyl-muramyl dipeptide (GMDP). A plasmid containing the HSV gD gene (pDNAgD) was used as an immunogen. GMDP and pDNAGM-CSF each enhanced the T-cell immune response to DNA immunization. The protective effect of DNA immunization increased from 63 to 100% when the two plasmids were injected simultaneously and to 96% when pDNAgD was injected one day after injecting GMDP. The results showed that DNA vaccines combined with genetic or peptide adjuvants are promising for DNA immunization against HSV.__________Translated from Molekulyarnaya Biologiya, Vol. 39, No. 3, 2005, pp. 504–512.Original Russian Text Copyright © 2005 by Kozlov, Klimova, Shingarova, Boldyreva, Nekrasova, Guryanova, Andronova, Novikov, Kushch.  相似文献   
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Cytological and molecular genetics methods were used to study sperm from patients with sperm infected with herpes simplex virus (HSV) as indicated by virological and immunocytochemical tests. The following methods were used: (1) sperm analysis to evaluate the morphology and functional properties of sperm; (2) fluorescence in situ hybridization (FISH) with DNA probes specific for chromosomes 1, X, and Y to evaluate nondisjunction frequencies of these chromosomes in sperm; and (3) quantitative analysis of immature germ cells in the ejaculate to identify spermatogenic abnormalities. The total sperm count and the count of sperm with normal motility proved similar to the norm. FISH analysis demonstrated no difference in the nondisjunction frequency of chromosomes 1, X, and Y between infertile patients with HSV-infected sperm and fertile donors. Comparative quantitative analysis of immature germ cells from the ejaculate has demonstrated a significant and considerable (threefold) increase in the number of spermatocytes I at the prepachytene stages of prophase I (preleptotene, leptotene, and zygotene) in HSV patients compared to normal donors. At the same time, HSV patients demonstrated a significant decrease in the number of spermatocytes I, a decrease in the proportion of spermatocytes II and spermatids, and a twofold increase in the number of unidentifiable immature germ cells. The data obtained indicate a partial spermatogenic arrest at the early stages of meiotic prophase I in HSV patients, which prompts further research into the cellular mechanisms of abnormal spermatogenesis after viral infection in humans.  相似文献   
28.
A series of ferrocenyl ended dendrons containing π-conjugated systems were obtained using Wittig and Heck reactions. The dendrons were attached to eight functionalized resorcinarenes via Williamson reaction obtaining high molecular weight dendrimers. No electronic communication between metal centers was observed by cyclic voltammetry. All the dendrimers were characterized by 1H, 13C NMR, FTIR, UV-Vis, MALDI-TOF, elemental analyses, and electrochemical studies.  相似文献   
29.
A synthetic scheme for preparation of (Gly-Pro) n , (Pro-Gly) n (n = 2, 3), and (Pro-Gly-Pro) n (n = 1, 2) peptides was elaborated. The effect of the synthesized peptides and the Gly-Pro and Pro-Gly dipeptides on survival of cultured cells of PC12 rat pheochromocytoma was studied under the conditions of oxidative stress induced by brief incubation of the cells with hydrogen peroxide. Peptides of the general formula (Gly-Pro) n and the Pro-Gly-Pro peptide at a concentration of 0.2–100 μM were shown to decrease the number of damaged cells. The Gly-Pro peptide was the most active and decreased the number of damaged cells by 49% on average at a concentration of 100 μM.  相似文献   
30.
The three main Lena Delta terraces were formed during different stages of the late Quaternary. While only the first floodplain terrace is connected with active deltaic processes, the second and third terraces, which dominate the western part of the delta, are erosional remnants of arctic paleolandscapes affected by periglacial processes. The landscape dynamics of the second and the third terraces, and their relationship to each other, are of particular importance in any effort to elucidate the late Quaternary paleoenvironment of western Beringia.Multidisciplinary studies of permafrost deposits on the second terrace were carried out at several sites of the Arga Complex, named after the largest delta island, Arga–Muora–Sise. The frozen sediments predominantly consist of fluvial sands several tens of meters thick, radiocarbon-dated from > 52 to 16 kyr BP. These sands were deposited under changing fluvial conditions in a dynamic system of shifting river channels, and have been additionally modified by synsedimentary and postsedimentary cryogenesis. Later thermokarst processes affected this late Pleistocene fluvial landscape during the Lateglacial and the Holocene. In addition, eolian activity reworked the fluvial sands on exposed surfaces at least since the Lateglacial, resulting in dune formation in some areas. Contrary to the Arga Complex, the third terrace is mainly composed of polygenetic alluvial and proluvial ice-rich permafrost sequences (Ice Complex deposits) radiocarbon-dated from 50 to 17 kyr BP which cover older fluvial sand units luminescence-dated to about 100–50 kyr BP. Paleoecological records reflect tundra-steppe conditions that varied locally, depending on landscape dynamics, during the Marine Isotope Stage (MIS) 4 and 3 periods, and a persistent change to shrub and arctic tundra during Lateglacial and Holocene periods.The study results indicate a continuous fluvial sedimentation environment for the Laptev Sea shelf in the region of the second Lena Delta terrace during the late Pleistocene, and confirm the presence of a dynamic channel system of the paleo-Lena River that flowed at the same time as the nearby subaerial Ice Complex deposits were being formed.  相似文献   
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