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101.
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
102.
Melanoma is the most lethal cutaneous cancer with a highly aggressive and metastatic phenotype. While recent genetic and epigenetic studies have shed new insights into the mechanism of melanoma development, the involvement of regulatory non‐coding RNAs remain unclear. Long non‐coding RNAs (lncRNAs) are a group of endogenous non‐protein‐coding RNAs with the capacity to regulate gene expression at multiple levels. Recent evidences have shown that lncRNAs can regulate many cellular processes, such as cell proliferation, differentiation, migration and invasion. In the melanoma, deregulation of a number of lncRNAs, such as HOTAIR, MALAT1, BANCR, ANRIL, SPRY‐IT1 and SAMMSON, have been reported. Our review summarizes the functional role of lncRNAs in melanoma and their potential clinical application for diagnosis, prognostication and treatment. 相似文献
103.
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
104.
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
105.
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
106.
107.
L. M. Zalyalyutdinova A. G. Bikmullin R. I. Tukhbatova A. A. Nabatov N. V. Petrova T. V. Bagaeva F. K. Alimova 《Applied Biochemistry and Microbiology》2018,54(2):211-214
The secondary peptide metabolites produced by the Trichoderma asperellum strain F-1087 were isolated, and their properties were studied. It has been shown these metabolites at concentrations of 0.08 and 0.02 mg/mL inhibit the human prostate cancer cell line by 97 and 34%, respectively. 相似文献
108.
In warm-blooded vertebrates, the α- and β-globin genes are organized in domains of different types and are regulated in different fashion. In cold-blooded vertebrates and, in particular, the tropical fish Danio rerio, the α- and β-globin genes form two gene clusters. A major D. rerio globin gene cluster is in chromosome 3 and includes the α- and β-globin genes of embryonic-larval and adult types. The region upstream of the cluster contains c16orf35, harbors the main regulatory element (MRE) of the α-globin gene domain in warm-blooded vertebrates. In this study, transient transfection of erythroid cells with genetic constructs containing a reporter gene under the control of potential regulatory elements of the domain was performed to characterize the promoters of the embryonic-larval and adult α- and β-globin genes of the major cluster. Also, in the 5th intron of c16orf35 in Danio rerio was detected a functional analog of the warm-blooded vertebrate MRE. This enhancer stimulated activity of the promoters of both adult and embryonic-larval α- and β-globin genes. 相似文献
109.
110.
Katerina Stambolieva Dorina Petrova Mariya Irikeva 《Somatosensory & motor research》2017,34(2):129-133
Purpose: To evaluate the effectiveness of 8-week low-frequency plantar vibration training on patients with sensorimotor diabetic peripheral neuropathy (DPN).
Participants: Twelve patients took part in the investigation.
Results: An increase of the nerve conductive velocity of soral and peroneal nerves of feet, increased postural stability, and disappearance of the pain and tingling were observed.
Conclusion: The obtained results provide evidence for beneficial effects of 8-week plantar vibration training in patients with DPN. 相似文献