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991.
Comparative study of fatty acid composition of total phospholipids, as well as of phosphatidylcholine and phosphatidylethanolamine from hepatopancreas and leg muscle was performed on several representatives of gasteropods (Gastropoda) molluscs and bivalve (Bivalvia) mussel (Mytilus edulus). The objects of our study were marine litorins (Littorina saxsatilis) adapted to different temperature conditions of White Sea and Barents Sea, freshwater lymnaea (Lymnaea stagnalis) infested by Trematoda and mussels from White Sea and Black Sea. It was shown that depending on the existence conditions of studied tissue or lipid, the maximal change is observed in the percentage of saturated acids (4-83 %), the percentage of unsaturated acids was less expressed (1-14 %) and the changes in unsaturation index (UI) did not exceed 20 % on average. It was supposed that observed quantitative bounds of UI change under the action of different external factors is utmost for maintenance of membrane fluidity necessary for normal vital activity of cell, particularly in studied ectothermic molluscs.  相似文献   
992.
The structures of antennal segments and ultrastructures of antennal sensilla were studied in representatives of 28 families of caddisflies from both extant suborders by the methods of light and scanning electron microscopy. Sixteen types of the sensilla have been found to occur on the antenna in Trichoptera; some of them were found for the first time. Morphological characters of the cuticular structures on the antennal surface demonstrate the significant structural differences both in various families and in the lower taxonomy levels. Specialized sensory fields differing structurally from the rest of the flagellomer surface have been found on the antennas in the suborder Phryganeina. A modified classification of sensilla based on the cuticular structures is proposed.  相似文献   
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994.
A search for poly(ADP-ribose) polymerase-1 inhibitors by virtual screening of a chemical compound database and a subsequent experimental verification of their activities have been done. It was shown that the most efficient method to predict inhibitory properties implies a combinatorial approach joining molecular docking capabilities with structural filtration. Among more than 300000 database chemicals 9 PARP1 inhibitors were revealed; the most active ones, namely: STK031481, STK056130, and STK265022,--displayed biological effect at a micro-molar concentration (IC50 = 2.0 microM, 1.0 microM and 2.6 microM, respectively).  相似文献   
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Microsporidia is a large group of fungi-related unicellular eukaryotes with obligate intracellular lifestyle infecting a wide range of invertebrate and vertebrate hosts. Long adaptation of the parasites to intracellular development resulted in extraordinary minimization of their metabolic system. The paper summarizes the original results and literature data on the study of microsporidian carbohydrate and energy metabolism. On the basis of the material, it is concluded that minimization of microsporidian cell machinery was accompanied by the acquisition of a number of unique characteristics, which were not found in other eukaryotes.  相似文献   
998.
The rat represents very important, superior in many respects to the mous, animal model for studying pharmacology, physiology, ageing, cardiovascular etc. However, numerous attempts to derive rat ES cells necessary to carry out loss-of-gene-function studies have not been successful thus far. Therefore rat induct pluripotent stem cells (or riPS) should provide a notable alternative to ES cell, allowing to study gene functions in this valuable animal model. Here we report an improved lentivirus-based riPS derivation protocol that makes use of small inhibitors of MEK and GSK3. We show that the excision of proviruses does not affect neither karyotype and pluripotency state of these cells. Also, we propose genetic tool for an improvement of the quality of riPS cells in culture. These data may prompt further iPS-based gene targeting in rat as well as the development iPS-based gene therapies, using this animal model.  相似文献   
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