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991.
M. I. Ibragimova A. I. Chushnikov G. V. Cherepnev V. Yu. Petukhov E. P. Zheglov 《Biophysics》2014,59(3):425-430
The iron metabolism was studied in serum blood samples collected from 26 professional sportsmen undergoing intensive physical exercises using EPR combined with hematological and biochemical laboratory tests. Only 23% of EPR spectra (n = 6) were practically normal while in the rest spectra additional abnormal absorption lines were detected. Presumably, the significant portion of new signals may be caused by different cytochromes. Moreover, the anisotropic signals with g 1 ? 2.02; g 2 ? 1.94 and g 3 ? 1.86 registered in some spectra pointed to the sulfur-iron centers. There was nearly linear correlation between the concentration of Fe3+ in transferrin (Fe3+-Tf) obtained from the EPR spectra and the serum iron concentration measured by absorption photometry both for sportsmen and controls (healthy individuals and patients with different diseases). At equal serum iron concentrations the Fe3+-Tf level was higher in sportsmen than that in controls. The Pearson correlation coefficient (r) for Fe3+-Tf and serum iron values was equal to 0.89 in sportsmen versus r = 0.97 in controls. Additional new lines in serum EPR spectra of professional sportsmen prove the suitability of EPR assay for scheduled medical exams since routine biochemical and hematological tests are insufficient to discover all abnormalities in iron metabolism under intensive physical exercises. 相似文献
992.
Following the discovery of synergistic action between oxacillin and manuka honey against methicillin-resistant Staphylococcus aureus, this study was undertaken to search for further synergistic combinations of antibiotics and honey that might have potential in treating wounds. Fifteen antibiotics were tested with and without sublethal concentrations of manuka honey against each of MRSA and Pseudomonas aeruginosa using disc diffusion, broth dilution, E strip, chequerboard titration and growth curves. Five novel antibiotic and manuka honey combinations were found that improved antibacterial effectiveness in vitro and these offer a new avenue of future topical treatments for wound infections caused by these two important pathogens. 相似文献
993.
Ohne ZusammenfassungProceedings of the Meetings of Saturday September 26, 1908.Die vorliegende Übersetzung, zu der Herr Prof. Went mich gütigst autorisierte, rechtfertigt sich durch die in theoretischer, ganz besonders aber in methodologischer Hinsicht überaus wichtigen Ergebnisse Blaauws. Die Untersuchung bestätigt zunächst ein Gesetz, das der Übersetzer für die Abhängigkeit der Präsentationszeit von der Lichtintensität festgestellt hat (die diesbezügliche Abhandlung war Herrn Prof. Went zur Zeit, als er dieses Referat schrieb, noch nicht zu Gesicht gekommen), verfolgt aber diese Gesetzmäßigkeit innerhalb wesentlich weiterer Grenzen. Die Feststellung ganz besonders, daß bei entsprechend intensiver Beleuchtung die Präsentationszeit bis auf 1/1000 Sekunde sinkt, zusammengehalten mit den Tatsachen der feinen Unterschiedsempfind-lichkeit der Pflanzen (Wiesner) und der außerordentlich kurzen Perzeptions-zeit (Fitting), muß die reizphysiologische Methodik reformieren und sie zu ebenso exaktem Arbeiten anspornen, wie es bei psychophysischen Experimenten längst der Fall ist. 相似文献
994.
Isoforms of myosin and actin in human, monkey and rat myometrium. Comparison of pregnant and non-pregnant uterus proteins 总被引:1,自引:0,他引:1
Using several electrophoretic procedures, we have compared the forms of myosin and actin in pregnant and non-pregnant uterus of woman, monkey (Macaca fascicularis) and rat. On non-dissociating gels, native myosin of the three species migrates as a single band, of identical mobility independently of the physiological state. Remigration of this band in dissociating conditions shows that it is constituted of two heavy chains of respectively 201 kDa and 205 kDa; the relative proportions of these two bands are different for the three animal species but do not vary during pregnancy. Using two-dimensional gel electrophoresis, we found that the 17-kDa light chain of purified uterus myosin exists under two isoelectric forms, the more acidic one becoming progressively predominant at the end of pregnancy in the human as in the monkey uterus, while we observed no changes in the rat. In two-dimensional gel electrophoresis, actin of human, monkey and rat uterus is present under three isoforms, the most basic one (the gamma form) increasing early in pregnancy in the two primate species but being always the most abundant form in the rat. The ATPase activity of human uterus myosin was found to be similar for the protein extracted from both pregnant and non-pregnant uterus. The changes observed in the 17-kDa light chain and in the actin isoforms might nevertheless participate in the modifications of contractility of the uterus during pregnancy of the primates. 相似文献
995.
The relation between the logarithm of the volume of the embryo and the number of somites was studied in the mouse and rat in the period of about 0-43 somites, a period characterized by a very rapid volume increase. A linear relation was found, and the variability of the individual observations around the straight line was rather small. Using a previously defined age estimate, i.e. the 'developmental age' based on the embryonic volume, we also found a linear relation between this age estimate and the number of somites. With the help of this straight line, the developmental age can be estimated from the number of somites with an accuracy of less than 0.1 day. Therefore, the developmental age can be considered a better age estimate than those based on the usual methods. The time needed to form a new somite was found to be constant in both species during the period studied. The length of the period differed, and was 1.68 h in the mouse and 2.24 h in the rat. However, the volume of the embryo at the time when a specific somite was formed (for instance the 25th) appeared to be the same in both species. Comparison of the volume of embryos, embedded in paraffin and Epon and sectioned, enabled us to estimate the shrinkage in Epon embryos. The volume after processing was approximately 62% of the original volume. 相似文献
996.
997.
998.
Sally P Wheatley 《Cell cycle (Georgetown, Tex.)》2015,14(2):261-268
Survivin is a multitasking protein that can inhibit cell death and that is essential for mitosis. Due to these prosurvival activities and the correlation of its expression with tumor resistance to conventional cancer treatments, survivin has received much attention as a potential oncotherapeutic target. Nevertheless, many questions regarding its exact role at the molecular level remain to be elucidated. In this study we ask whether the extreme C- and NH2 termini of survivin are required for it to carry out its cytoprotective and mitotic duties. When assayed for their ability to act as a cytoprotectant, both survivin1–120 and survivin11–142 were able to protect cells against TRAIL-mediated apoptosis, but when challenged with irradiation cells expressing survivin11–142 had no survival advantage. During mitosis, however, removing the NH2 terminal 10 amino acids (survivin11–142) had no apparent effect but truncating 22 amino acids from the C-terminus (survivin1–120) prevented survivin from transferring to the midzone microtubules during anaphase. Collectively the data herein presented suggest that the C-terminus is required for cell division, and that the NH2 terminus is dispensable for apoptosis and mitosis but required for protection from irradiation. 相似文献
999.
1000.