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951.
The analysis of the original sources showed that there are some differences in approaches to radiation injuries treatment used mainly by Russian and foreign researches in their experiments. In Russian radiobiology the main way was the single usage of high molecular substances of different chemical structure and of natural origin soon after radiation exposure. These substances were designated then as cytokine inductors. Foreign researchers investigated in the beginning analogous substances too, but then--recombinant cytokines exclusively. In native radiobiology the urgent (in limits of 2 h) and early (in limits of 6-24 h) pathogenic therapy develops already for a long time. There are preparations, betaleukine (recombinant human interleukine 1 beta) and dezoksinat (degraded DNA), as results of developing the directions. Both have licenses on the administration at radiation accidents. But the issues of various medicaments optimal combinations in a common scheme of early (in first 24 h) medical help remain undefined accurately. The consensus protocol of radiation injuries treatment in clinic consists of the supportive therapy (aseptic conditions, wide antimicrobic antibiotics, thrombocytes and erythrocytes transfusions) and the myelostimulation therapy by cytokine combinations. The hemopoietic stem cells transplantation in cases of severe radiation damages treatment remains under question in the reason of immunological conflict between a host and a graft.  相似文献   
952.
The membrane potential responses evoked by GABA and glycine bath applications were studied intracellularly in the motoneurons of the isolated frog spinal cord. The amplitude of glycine-evoked responses was 1.5-2.0 larger than that of GABA-evoked response at the same concentration. EC50 were 0.75 mM and 1.57 mM for glycine and GABA, respectively. The amplitude of responses induced by the simultaneous applications of both agonists were 79.1 +/- 2.4% (n = 19) of the sum of individual responses and 130.1 +/- 1.5% (n = 19) of individual glycine-induced responses (partial occlusion). GABA-evoked responses were decreased by 85.3 +/- 0.2% (n = 10) as a result of glycine preliminary application while preapplication of GABA reduced glycine-evoked responses only by 52.9 +/- 0.3% (n = 11). Glycine- and GABA-evoked responses were selectively suppressed by strychnine and bicuculline, respectively. These results suggest that amphibian spinal motoneurones express (less specifically than those of mammals) both glycine (predominantly) and GABAA receptors, with asymmetric cross-inhibition possibly taking place in them.  相似文献   
953.
The changes studied in 137Cs uptake by plants and its distribution between vegetative and generative organs of barley cultivated with the application of potassium humate. A relationship has been found between 137Cs accumulation size in barley at various ontogenesis stages and way of potassium humate application (treatment of seeds or plants), as well as availability of mineral nutrients in the soil. Changes in K+ and NH4+ concentrations in soil solution are shown to be of prevailing importance in regulating 137Cs uptake by plants compared with potassium humate effects.  相似文献   
954.
Lipid content of tissue and of fraction of microsomes in neocortex of Wistar rats was studies under artificial hypothermia, after X-ray irradiation in dose 8 Gy under conditions of normothermia and artificial hypothermia in 48 h. The condition of artificial hypothermia get by cooling of rats to 15-18 degrees C. It was shown, that in fraction of microsomes of hypothermia rats the content of phosphatidylinositol was decreased, and in 48 h after cooling of rats the amount of protein, total and individual phospholipids was increased. The lipid content in tissue and in fraction of microsomes of rats, which were irradiated in normotermia, had no changes after 48 h. In fraction of microsomes of rats, which were irradiated after hypothermia, the amount of protein, total phospholipids, sphingomyelin, phosphatidylcholine and phosphatidylserine is increased trustworthy. Thus, we think, that radioprotective effect of hypotermia may be connected with the accumulation of proteins and of phospholipids in the endoplasmic reticulum membranes of neocortex.  相似文献   
955.
232Th and Ce (III) toxic effects and its modifications with caffeine and D,L-buthionine-(S,R)-sulphoximine on Chlorella vulgaris Beijer were studied using an optical density measure after 24 hours growth. Concentrations of 232Th or of Ce--toxic effect relationship were shown to be nonlinear. In the first (nontoxic) concentration range (for Ce 0.036-1.642 micromol/L and for 232Th 0.001-1.551 micromol/L) algae biomass production registered by optical density do not significantly differ from the control one. In the second (toxic) concentration range dose-effect relationship for 232Th is characterized with quadratic dependence and in the case of Ce--with exponential dependence. 232Th radiation component contribution into effect observed is appeared as induction of DNA damages additional to spontaneous at the radionuclide concentration (equal to 0.345 micromol/L) that is three times lower than in case of the non-radioactive chemical analog Ce (1.071 micromol/L).  相似文献   
956.
957.
The effects of inbreeding and low temperature on the pattern of homologous chromosome synapsis in ovarian nurse cell nuclei of Drosophila melanogaster strains were studied. Exposure to decreased temperature (16 degrees C) caused a noticeable increase in the rate of asynapses of homologous chromosomes, whereas this effect was insignificant for F30 inbreeding generation. Long-term inbreeding has a substantial effect on the relative positions of chromosomes in the nurse cell nuclei. This is visually evident only in the interstrain hybrids between highly inbred strains LA (F923) and HA (F923) or between either strain and laboratory strain Canton S or the flies from the natural population, where abnormalities in homologous chromosome synapsis are observed in virtually all nuclei.  相似文献   
958.
Four population samples of Pacific capelin Mallotus villosus catervarius (Pennant, 1784) from geographically distant localities in the Sea of Okhotsk, Tauy Bay and the eastern coast of the Sakhalin Island, were examined using PCR-RFLP analysis of three mitochondrial DNA regions (A8/A6/COIII/ND3, ND3/ND4L/ND4, and ND5/ND6). The nucleotide divergence of mtDNA sequences among the samples, as well as the analysis of geographic heterogeneity of the haplotype frequencies and quantitative estimation of genetic differentiation performed by means of AMOVA, showed that the samples examined belonged to one panmictic population. Genealogic analysis of the mtDNA variation structure was carried out. It was demonstrated that the high level of haplotype diversity (0.9639 +/- 0.00015) along with the low level of nucleotide diversity (0.003818 +/- 0.0000003) pointed to the exponential rate of population growth of the capelin from the Sea of Okhotsk, which rather recently in its evolutionary history faced the bottleneck effect.  相似文献   
959.
Allelic imbalances (AI) of polymorphic markers at the short arm of chromosome 3 (3p) were mapped using DNA samples of renal cell carcinoma (RCC, 80 cases), breast carcinoma (BC, 95 cases), and epithelial ovarian cancer (EOC, 50 cases) at the same dense panel of markers (up to 24 loci). Six regions with the increased AI frequency (versus the average values determined for all the analyzed 3p markers) at RCC, BC or EOC were found in 3p chromosome. Four 3p regions presumably contain suppressor genes of tumor growth (TSG) observed in the epithelial tumors of various types. Region between D3S2409 and D3S3667 markers in the 3q21.31 region was identified in this study for the first time. The AI peak in D3S2409-D3S3667 region was statistically significant (P < 0.001, according to Fisher) when representative sample of 95 BC patients was analyzed. The data on increased frequency of polymorphic marker allele amplification suggest that the D3S2409-D3S3667 region contains both putative TSG and protooncogenes.  相似文献   
960.
Three new microsatellite loci found for the Baikal omul Coregonus migratorius (Georgi) are described.  相似文献   
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