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排序方式: 共有803条查询结果,搜索用时 109 毫秒
101.
V P Lozvo? S V Kaznacheev V A Kozlov E M Petrova 《Zhurnal mikrobiologii, epidemiologii, i immunobiologii》1975,(5):108-111
Experiments were conducted on CBA mice. The effect of heparin and of the fraction of human blood plasma precipitated by heparin (FPH) on the course of the specific immunity reaction, i.e. of rosette-formation, was studied. Inhibition of the mentioned reaction by FPH was revealed. No such effect was produced by heparin. Experiments were carried out in vitro. The results of the mentioned experiments were compared with literature data on the effect of heparin and FPH on other immunological reactions. A supposition was put forward that these substances interacting with lymphocytes had different points of application: heparin-cellular membrane, FPH-superficial cell receptors. 相似文献
102.
103.
S A Novitskaia I V Petrova N G Serebriakov I G Vasina 《Biulleten' eksperimental'no? biologii i meditsiny》1975,80(9):66-68
A study was made of the effect of heparin on the capacity of the human blood lymphocytes to blast-transformation in response to the stimulation with antilymphocytic gamma-globulin and phytohemagglutinin. Heparin proved to inhibit more intensively the transformation of lymphocytes stimulated by the antilymphocytic gamma globulin. The depressive effect arose when heparin was injected one hour before the mitogen, simultaneously with it and one hour after it. 相似文献
104.
105.
R. A. Zinchenko A. Kh. Makaov V. V. Kadyshev V. A. Galkina E. L. Dadali L. K. Mikhailova M. F. Shurygina A. V. Marakhonov N. V. Petrova N. E. Petrina G. I. El’chinonva P. Gundorova A. S. Tanas V. V. Strelnikov A. V. Polyakov E. K. Ginter 《Russian Journal of Genetics》2018,54(7):858-865
The diversity and prevalence of hereditary diseases (HDs) among Nogais of the Karachay-Cherkess Republic (KChR) are described. The size of the surveyed KChR population was 387231 individuals, including 3.81% Nogais (14741 individuals). We revealed 36 nosological forms of HDs (110 patients from 81 families): 22 with autosomal dominant (AD) inheritance, 10 with autosomal recessive (AR) inheritance, and 4 with X-linked inheritance. The prevalence of HDs in Nogais was 1: 134. The features of HD diversity in Nogais were determined in comparison with the previously surveyed populations of Russia. The accumulation of Ehlers–Danlos syndrome (1: 388), AD amelogenesis imperfecta (1: 3685), AD ichthyosis (1: 4914), AR nonsyndromic mental retardation (1: 1340), AR Gilbert syndrome (1: 4914), and X-linked inherited deficit of glucose-6-dehydrogenase (1: 1774 males) was established. The analysis of heterozygous carriage of mutations “major” for Russia in the genes of the four following AR diseases in 118 unrelated clinically healthy Nogais (236 analyzed chromosomes) was performed: cystic fibrosis (13 mutations in the CFTR gene: CFTRdele2,3 (21 kb), F508del, I507del, 1677delTA, 2184insA, 2143delT, 2183AA>G, 2184delA, 394delTT, 3821delT, L138ins, E92K, W1282X); phenylketonuria (six frequent mutations in the PAH gene: R261X, R408W, R413P, F331S, P211T, P211L); nonsyndromic sensorineural hearing loss (35delG mutation in the GJB2 gene); and Gilbert syndrome (an increase in the number of TA repeats in the UGT1A1 gene). Allelic specificity for all studied genes in the Nogai people was revealed. 相似文献
106.
As a result of allozyme analysis, Nei’s genetic distances were determined between the phylogeographic group of seven populations of Pinus sylvestris L. in the “glacial” zone of the range in Central Yakutia and 25 populations of its hypothetical Pleistocene refugia of the southern nonglacial zone within the entire range of the species in Northern Eurasia. The location of the most likely “avant-garde” refugium of the modern yakutian populations of the Scots pine is Northern Priamur’e (Tynda), as well as less likely Siberian (Romanovka, Irkutsk), South Ural (Kryktytau), and Central European (the Czech Republic) refugia. 相似文献
107.
Anna Mamaeva Zorigto Namsaraev Yevhen Maltsev Evgeniy Gusev Maxim Kulikovskiy Maria Petrushkina Alla Filimonova Boris Sorokin Nikita Zotko Vladimir Vinokurov Dmitry Kopitsyn Daria Petrova Andrei Novikov Denis Kuzmin 《Journal of applied phycology》2018,30(4):2237-2246
Manipulation of the nutrient concentration is an inexpensive and efficient method for increasing lipid and TAG accumulation in algal cells. However, high volumetric production requires finding a proper balance between the decrease of biomass production and the increase in the total lipid content. We isolated a strain of green microalga Bracteacoccus bullatus and increased its lipid content from 17 to 59% of biomass dry weight by manipulating of nitrogen and phosphorus content in the medium. The 10-fold reduction of the nitrogen and phosphorus concentration in the medium was the most efficient method of the lipid induction compared to nutrient deplete and high nutrient conditions. The oleic (48–64% mass of total fatty acids) and linoleic (14–24% mass of total fatty acids) acids dominated in the fatty acid profile, thus making this strain a suitable candidate for biodiesel production. 相似文献
108.
Mutagenesis provoked by exposure to increased concentration of antibiotics of five indigenous Rhizobium galegae strains resulted
in the generation of several antibiotic-resistant mutants. The mutants differed from the wild type and one from another in
respect to the nodulation capacity, the nitrogenase activity, the nodule ultrastructure, and the plant growth response. Galega
plants inoculated with mutants resistant to streptomycin and rifampicin formed nodules with higher nitrogenase activity and
accumulated more shoot dry biomass than plants inoculated with the parent strains. Resistance to kanamycin and nalidixic acid
was associated with significant decrease of nitrogenase activity. A correlation between nitrogen-fixing efficiency and nodule
infected cell ultrastructure was found. When the bacteroids occupied about 10 times higher area in infected cells of nodule
than peribacteroid spaces and host cytosol had electron dense and homogenous structure, the nitrogenase activity was the highest.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
109.
N I Shapiro A E Khalizev E V Luss E S Manuilova O N Petrova N B Varshaver 《Mutation research》1972,16(7):89-101
Mutations controlling the resistance to 6-mercaptopurine (6-M) and the ability to multiply in a medium with a low concentration of glucose (“glucose-independent” mutants) were induced in cultured Chinese hamster cells by N-nitrosomethylurea (NMU), 5-bromodeoxyuridine (BUdR), UV and X-rays. The chemical agents were found to be very active in induction of mutations to 6-M resistance (NMU and BUdR) and mutations of “glucose independence” (NMU). These agents increase the yield of mutations as compared to the spontaneous mutation rate by about two orders of magnitude. The induced rate of 6-M-resistant mutations by X-rays was 2.0 ? 10−7 per viable cell per roentgen. BUdR approximately equally increases the cell's sensitivity to both inactivating and mutagenic action of X-rays. The maximum induction of mutations to 6-M resistance by UV was observed at 100 erg/mm2. This dose leads to 1 16-fold increase of the mutation frequency as compared to the spontaneous rate. Further increase of the UV dose up to 200 erg/mm2 resulted in a lower yield of mutations per dose unit. The highest yield of mutations to 6-M resistance induced by NMU, BUdR and X-rays was observed if cells were plated in selective medium several generations after the mutagenic treatment. The maximum yield of mutations to 6-M resistance induced by UV and of glucose-independence induced by NMU was recorded if cells were transferred to selective media immediately after treatment. The kinetics of expression of mutations and the decline of their number observed after prolonged incubation of treated cells in nonselective conditions are discussed. 相似文献
110.