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S. Rai Karamjit 《Journal of genetics》1999,78(3):163-169
Beginning in the mid-1950s, much progress has been made in studying various aspects of the genetics of mosquitoes, particularly involving several species of three principal genera,Aedes, Culex andAnopheles, that transmit important human diseases. Here I discuss selected areas of research involving formal genetics; genome structure, organization and evolution at the interspecific and intraspecific level; and evolutionary genetics of theAedes scutellaris group. Information and insights gained from in-depth analyses of these areas, particularly transmission genetics, cytogenetics and genetics of chromosomal rearrangements, and of mutagen-induced sexual sterility, have proved invaluable for the development of the theory and evaluation of feasibility of genetic control of natural populations. As a result, mosquitoes represent some of the best studied taxa at various levels of genetic organization. Recent developments in molecular genetics offer exciting possibilities for extension of these concepts. 相似文献
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Audesh Bhat Anil Koul Ekta Rai Swarkar Sharma M. K. Dhar R. N. K. Bamezai 《Human genetics》2008,123(1):115
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S. C. Rai 《Biometrical journal. Biometrische Zeitschrift》1987,29(4):449-454
A multi-sample slippage test based on ordered observations has been given. The test statistic is based on the sum of ranks of the sample. The probability distribution of the test statistic has been worked out for small sample and it turns out to be chi-square distribution for large sample. The analytical procedure has been explained by a numerical example. 相似文献
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EA Dukhanina TI Lukyanova EA Romanova V Guerriero NV Gnuchev GP Georgiev DV Yashin LP Sashchenko 《Cell cycle (Georgetown, Tex.)》2015,14(22):3635-3643
PGRP-S (Tag7) is an innate immunity protein involved in the antimicrobial defense systems, both in insects and in mammals. We have previously shown that Tag7 specifically interacts with several proteins, including Hsp70 and the calcium binding protein S100A4 (Mts1), providing a number of novel cellular functions. Here we show that Tag7–Mts1 complex causes chemotactic migration of lymphocytes, with NK cells being a preferred target. Cells of either innate immunity (neutrophils and monocytes) or acquired immunity (CD4+ and CD8+ lymphocytes) can produce this complex, which confirms the close connection between components of the 2 branches of immune response. 相似文献
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Methylammonium/ammonium ion, glutamine, glutamate, arginine and proline uptake, and their assimilation as nitrogen sources, was studied in Nostoc muscorum and its glutamine synthetase-deficient mutant. Glutamine served as nitrogen source independent of glutamine synthetase activity. Glutamate was not metabolised as a nitrogen source but still inhibited nitrogenase activity and diazotrophic growth. Glutamine synthetase activity was essential for the assimilation of N2, ammonia, arginine and proline as nitrogen sources but not for the control of their transport, heterocyst formation, and production of ammonia or aminoacid dependent repressor signal for N2-fixing heterocysts. These results also suggest that glutamine synthetase serves as the sole route of ammonia assimilation and glutamine synthesis, and ammonia per se as the repressor signal for N2-fixing heterocysts and methylammonium (ammonium) transport. 相似文献
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Nitrate metabolism in the cyanobacterium Anabaena cycadeae: Regulation of nitrate uptake and reductase by ammonia 总被引:2,自引:0,他引:2
Suvendra N. Bagchi Upendra N. Rai Amar N. Rai Hriday N. Singh 《Physiologia plantarum》1985,63(3):322-326
Nitrogen regulation of nitrate uptake and nitrate reductase (EC 1.7.99.4) was studied in the cyanobacterium Anabaena cycadeae Reinke and its glutamine auxotroph. Development of the nitrate uptake system preceded, and was independent of, the development of the nitrate reductase system. The levels of both systems were several-fold higher in the glutamine auxotroph lacking glutamine synthetase (EC 6.3.1.2) than in the wild type strain having normal glutamine synthetase activity. The nitrate uptake system was found to be NH4-repressible and the nitrate reductase system NO3 − -inducible. NH4 + was the initial repressor signal for the uptake process which was involved in the control of the NO3 − inducible reductase system. 相似文献
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Studies on the osmotic optima for growth of some Aspergilli isolated from Indian Usar (alkaline) soils have revealed the occurrence of four osmophilic and twenty-five other species which can be categorised as facultative tolerant on the basis of their osmotic concentration optima. In addition, the Usar soil strains possess a comparatively greater osmotic tolerance than their fertile soil counterparts which may be attributed to the relatively hypertonic conditions prevailing in Usar soils. 相似文献