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101.
L A Kraft C W Foley B Howarth M S Blum A D Johnson 《Comparative biochemistry and physiology. B, Comparative biochemistry》1978,60(3):233-238
1. The patterns of 14CO2 evolution from specifically labeled glucose substrates by washed bull, ram, boar, rabbit, dog, rooster and turkey spermatozoa were similar and indicated the Embden-Meyerhof and Kreb's cycle pathways as the major route of energy metabolism. 2. Honey bee spermatozoa metabolized glucose-3,4-[14C], glucose-[U-14C] or fructose-[U-14C], but not glucose-1-[14C], glucose-2-[14C]or glucose-6-[14C], indicating the presence of the glycolytic pathway, but the absence of respiration via the Kreb's cycle. 3. The rate of glycolysis exceeded the rate of respiration in the spermatozoa of all the species studied. 4. A preferential utilization of glucose-1-[14C] over glucose-6-[14C] was evident in some sperm samples, but no consistent indication of pentose cycle metabolism was observed, due to considerable variability between samples within each group. 5. Fructose metabolism was greater than glucose metabolism in the rooster, less in the dog, boar and turkey, and similar in the spermatozoa from the other species examined. 6. Only ram and bull spermatozoa metabolized acetate-1-[14C] to any extent. 相似文献
102.
Der Eingeweidesitus beim Alpenmolch (Triturus alpestris) nach UV-Bestrahlung von Prägastrula-Stadien
Dr. Arne v. Kraft 《Development genes and evolution》1969,163(2):178-183
Zusammenfassung Ungefurchte Eier, 4-Zellen-Stadien, 32–64-Zellen-Stadien und Blastulae wurden mit verschiedenen Dosen von UV-Mischlicht jeweils einseitig-äquatorial, -animal oder -vegetativ bestrahlt. In keiner Bestrahlungsgruppe bewirkte die UV-Bestrahlung eine wesentliche, statistisch bedeutsame Erhöhung der Eingeweide-Teilinversionen oder -Inversionen. Eine solche trat erst nach Bestrahlung junger Gastrulen auf. Dabei war die Exponierung der vegetativen Keimhälfte (einschlie\lich Urmund) besonders wirksam.
Mit Unterstützung der Deutschen Forschungsgemeinschaft. 相似文献
The situs viscerum of triturus alpestris after UV-irradiation in pregastrula stages
Summary Uncleaved eggs, eggs with 4, 32–64 blastomeres and blastulae were irradiated with different doses of UV-mixed light, only onesided-equatorial, -animal or -vegetativ. In no case did the UV-irradiation effect a statistically significant increase of whole or partial visceral inversions. These happened only after irradiation of young gastrulae, especially when the vegetative germ part with the blastopore was exposed.
Mit Unterstützung der Deutschen Forschungsgemeinschaft. 相似文献
103.
F William H T Haigler A S Kraft 《Biochemical and biophysical research communications》1989,160(2):474-479
To examine in vivo phosphorylation of lipocortin I we made use of a polyclonal antibody to an amino terminal peptide of lipocortin I. This antibody does not recognize any other member of the annexin protein family, and can both immunoprecipitate lipocortin I and recognize this protein on western blots. Using cleaved forms of lipocortin I, we have been able to demonstrate that protein kinase C phosphorylates this protein in vitro within the first 29 amino terminal amino acids. However, the addition of phorbol esters to A431 cells over a wide range of concentrations and for varying periods of time did not stimulate the phosphorylation of this protein. Since in vitro lipocortin I is an excellent substrate for all three isoforms, alpha, beta, gamma, of protein kinase C, the discrepancy in these findings is not secondary to the presence of varying forms of this protein kinase within different cell types. 相似文献
104.
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107.
Thomas Wernberg Mads S. Thomsen Sean D. Connell Bayden D. Russell Jonathan M. Waters Giuseppe C. Zuccarello Gerald T. Kraft Craig Sanderson John A. West Carlos F. D. Gurgel 《PloS one》2013,8(11)
Explaining spatial patterns of biological organisation remains a central challenge for biogeographic studies. In marine systems, large-scale ocean currents can modify broad-scale biological patterns by simultaneously connecting environmental (e.g. temperature, salinity and nutrients) and biological (e.g. amounts and types of dispersed propagules) properties of adjacent and distant regions. For example, steep environmental gradients and highly variable, disrupted flow should lead to heterogeneity in regional communities and high species turnover. In this study, we investigated the possible imprint of the Leeuwin (LC) and East Australia (EAC) Currents on seaweed communities across ~7,000 km of coastline in temperate Australia. These currents flow poleward along the west and east coasts of Australia, respectively, but have markedly different characteristics. We tested the hypothesis that, regional seaweed communities show serial change in the direction of current flow and that, because the LC is characterised by a weaker temperature gradient and more un-interrupted along-shore flow compared to the EAC, then coasts influenced by the LC have less variable seaweed communities and lower species turnover across regions than the EAC. This hypothesis was supported. We suggest that this pattern is likely caused by a combination of seaweed temperature tolerances and current-driven dispersal. In conclusion, our findings support the idea that the characteristics of continental-scale currents can influence regional community organisation, and that the coupling of ocean currents and marine biological structure is a general feature that transcends taxa and spatial scales. 相似文献
108.
We have analysed samples from Sweden, Denmark, and Germany of six facultatively apomictic blackberry species to investigate the accordance between a taxonomy based on morphological characters on the one hand, and distribution of genetic variation estimated by DNA fingerprinting on the other hand. DNA fingerprint variation was found to be quite restricted in all species investigated. The first taxonomic group included three species related toRubus nessensis, two being characterized by one very widespread DNA fingerprint in all three countries and a few rare ones, whereas the third species differed between Sweden and Germany. The second taxonomic group included species related toR. gracilis. Two of these species exhibited very similar DNA fingerprints, whereas the third species deviated clearly. The utilization of DNA fingerprinting as a tool in taxonomy is discussed; most likely this method could become a useful complement to morphology, especially in plant groups with reduced levels of genetic recombination. 相似文献
109.
GxG epistasis in growth and condition and the maintenance of genetic polymorphism in Gambusia holbrooki 下载免费PDF全文
Zachary W. Culumber Brittany Kraft Valerie Lemakos Erika Hoffner Joseph Travis Kimberly A. Hughes 《Evolution; international journal of organic evolution》2018,72(5):1146-1154
Theory on indirect genetic effects (IGEs) indicates that variation in the genetic composition of social groups can generate GxG epistasis that may promote the evolution of stable polymorphisms. Using a livebearing fish with a genetic polymorphism in coloration and associated behavioral differences, we tested whether genotypes of social partners interacted with focal individual genotypes to influence growth and condition over 16 weeks of development. We found that IGEs had a significant influence on patterns of feeding, regardless of focal fish genotype. There was no influence of social environment on juvenile length, but there was significant GxG epistasis for body condition. Each focal juvenile was in better condition when its own genotype was not present in adult social partners. These data are consistent with negative frequency‐dependent selection in which each morph performs better when it is rare. Neither variation in feeding nor activity‐related behaviors explained variation in body condition, suggesting that GxG epistasis for condition was caused by physiological differences between the two genotypes. These findings indicate that GxG epistasis in a given polymorphism can generate fitness landscapes that contribute to the maintenance of that polymorphism and to maintenance of genetic variation for additional fitness‐related traits. 相似文献
110.
Massive up‐regulation of LBD transcription factors and EXPANSINs highlights the regulatory programs of rhizomania disease 下载免费PDF全文