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111.
The results of studies based on multilocus molecular analyses, including random amplified polymorphic DNA (RAPD), inter-simple sequence repeat (ISSR), and amplified fragment length polymorphism (AFLP) analyses, are usually presented in the form of images (electrophoregrams, photographs, etc.). The interpretation of this information is complicated, labor-consuming, and subjective. Artificial neural networks (ANNs), which are ideal image processors, may be useful when solving such tasks. The possibility of using ANNs for the treatment of the results of RAPD and ISSR analyses has been studied. The RAPD and ISSR fragment spectra of the genus Capsicum L. (peppers) were used in this study. The results of clustering the accessions studied by means of the unweighted pair-group method with arithmetic averages (UPGMA), which is often used for phylogenetic constructions based on RAPD and ISSR data, serve as expert estimates. Fundamentally new methods of genetic polymorphism estimation using ANN technologies, namely, self-organizing feature maps (SOFMs) have been developed. The results show that the clusters obtained with the use of UPGMA and SOFM coincide by more than 90%; taking into account that ANNs can deal with high noise levels and incomplete or contradictory data, the approach proposed may prove to be efficient.Translated from Genetika, Vol. 41, No. 2, 2005, pp. 269–278.Original Russian Text Copyright © 2005 by Ruanet, Kochieva, Ryzhova. 相似文献
112.
W. C. Black IV E. S. Krafsur 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1985,70(5):491-496
Summary A FORTRAN program was written that calculates composite linkage disequilibrium coefficients from genotypic data. Chi-square tests determine whether coefficients calculated for allele and locus pairs are significantly greater than zero. A subroutine is provided that partitions the variance in linkage disequilibrium into within- and between-subpopulation components. Output obtained from analysis of allozyme data collected from natural subpopulations of the house fly (Musca domestica L.) are included to illustrate features of the program.Journal Paper No. J-11345 of the Iowa Agriculture and Home Economics Experiment Station, Ames, Iowa. Project No. 2411 相似文献
113.
Frederic T. Billings IV Michael R. Petracek L. Jackson Roberts II Mias Pretorius 《PloS one》2015,10(2)
BackgroundCardiopulmonary bypass (CPB) lyses erythrocytes and induces lipid peroxidation, indicated by increasing plasma concentrations of free hemoglobin, F2-isoprostanes, and isofurans. Acetaminophen attenuates hemeprotein-mediated lipid peroxidation, reduces plasma and urine concentrations of F2-isoprostanes, and preserves kidney function in an animal model of rhabdomyolysis. Acetaminophen also attenuates plasma concentrations of isofurans in children undergoing CPB. The effect of acetaminophen on lipid peroxidation in adults has not been studied. This was a pilot study designed to test the hypothesis that acetaminophen attenuates lipid peroxidation in adults undergoing CPB and to generate data for a clinical trial aimed to reduce acute kidney injury following cardiac surgery.ConclusionsIntravenous acetaminophen attenuates the increase in intraoperative plasma isofuran concentrations that occurs during CPB, while urinary markers were unaffected.
Trial Registration
ClinicalTrials.gov NCT01366976相似文献114.
Mark J. Butler IV Donald C. Behringer Jr. Thomas W. Dolan III Jessica Moss Jeffrey D. Shields 《PloS one》2015,10(6)
Sociality has evolved in a wide range of animal taxa but infectious diseases spread rapidly in populations of aggregated individuals, potentially negating the advantages of their social interactions. To disengage from the coevolutionary struggle with pathogens, some hosts have evolved various forms of “behavioral immunity”; yet, the effectiveness of such behaviors in controlling epizootics in the wild is untested. Here we show how one form of behavioral immunity (i.e., the aversion of diseased conspecifics) practiced by Caribbean spiny lobsters (Panulirus argus) when subject to the socially transmitted PaV1 virus, appears to have prevented an epizootic over a large seascape. We capitalized on a "natural experiment" in which a die-off of sponges in the Florida Keys (USA) resulted in a loss of shelters for juvenile lobsters over a ~2500km2 region. Lobsters were thus concentrated in the few remaining shelters, presumably increasing their exposure to the contagious virus. Despite this spatial reorganization of the population, viral prevalence in lobsters remained unchanged after the sponge die-off and for years thereafter. A field experiment in which we introduced either a healthy or PaV1-infected lobster into lobster aggregations in natural dens confirmed that spiny lobsters practice behavioral immunity. Healthy lobsters vacated dens occupied by PaV1-infected lobsters despite the scarcity of alternative shelters and the higher risk of predation they faced when searching for a new den. Simulations from a spatially-explicit, individual-based model confirmed our empirical results, demonstrating the efficacy of behavioral immunity in preventing epizootics in this system. 相似文献
115.
Bathri N. Vajravelu Kyung U. Hong Tareq Al-Maqtari Pengxiao Cao Matthew C. L. Keith Marcin Wysoczynski Zhao John Joseph B. Moore IV Roberto Bolli 《PloS one》2015,10(10)
A recent phase I clinical trial (SCIPIO) has shown that autologous c-kit+ cardiac progenitor cells (CPCs) improve cardiac function and quality of life when transplanted into patients with ischemic heart disease. Although c-kit is widely used as a marker of resident CPCs, its role in the regulation of the cellular characteristics of CPCs remains unknown. We hypothesized that c-kit plays a role in the survival, growth, and migration of CPCs. To test this hypothesis, human CPCs were grown under stress conditions in the presence or absence of SCF, and the effects of SCF-mediated activation of c-kit on CPC survival/growth and migration were measured. SCF treatment led to a significant increase in cell survival and a reduction in cell death under serum depletion conditions. In addition, SCF significantly promoted CPC migration in vitro. Furthermore, the pro-survival and pro-migratory effects of SCF were augmented by c-kit overexpression and abrogated by c-kit inhibition with imatinib. Mechanistically, c-kit activation in CPCs led to activation of the PI3K and the MAPK pathways. With the use of specific inhibitors, we confirmed that the SCF/c-kit-dependent survival and chemotaxis of CPCs are dependent on both pathways. Taken together, our findings suggest that c-kit promotes the survival/growth and migration of human CPCs cultured ex vivo via the activation of PI3K and MAPK pathways. These results imply that the efficiency of CPC homing to the injury site as well as their survival after transplantation may be improved by modulating the activity of c-kit. 相似文献
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118.
V. V. Kuz’mina L. K. Gavrovskaya P. V. Rusanova E. A. Kulivatskaya O. V. Ryzhova 《Inland Water Biology》2011,4(2):242-248
Upon a single injection, taurine (50 and 300 mg/kg) and its amide derivative taurepar (50 mg/kg), irrespective of diet and
kinds of stress, as a rule, slightly influence the glycemia level in carp. A long-term load of taurine (a total dose of 1250
mg/kg) significantly reduces the glucose concentration in the blood of fishes kept on a carbohydrate diet. Both preparations
existentially change the ratio of proteolytic (PA) and amylolitic (AA) activities in all studied fish. As a result, the G/P
coefficient increases considerably. It is suggested that the increase in glycosidase activity under taurine injections has
an adaptive significance for benthophagous carp, a large part of the diet of which consists of carbohydrate components. 相似文献
119.
120.
T. E. Soktoeva G. L. Ryzhova K. A. Dychko V. V. Khasanov S. V. Zhigzhitzhapova L. D. Radnaeva 《Russian Journal of Bioorganic Chemistry》2013,39(7):761-764
Isolation of artemisinin from Artemisia annua L. and its quantification by the HPLC-MS method are considered. Different extraction methods were used for the isolation of artemisinin: maceration, ultrasonic and subcritical CO2-extraction. The component content of the CO2- and hexane extracts was studied by the GC-MS method. 相似文献