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171.
Klaus Sch?fer Antonios Kyriakopoulos Hildegard Gessner Tilman Grune Dietrich Behne 《Journal of trace elements in medicine and biology》2004,18(1):89-97
The hepatic fatty acid metabolism was investigated in rats stressed by selenium deficiency and enhanced fish oil intake. Changes in the composition of lipids, peroxides, and fatty acids were studied in the liver of rats fed either a Sedeficient (8 microg Se/kg) or a Se-adequate (300 microg Se/kg) diet, both rich in n-3 fatty acid-containing fish oil (100 g/kg diet) and vitamin E (146 mg alpha-tocopherol/kg diet). The two diets were identical except for their Se content. Se deficiency led to a decrease in hair coat density and quality as well as to changes in liver lipids, individual lipid fractions and phospholipid fatty acid composition of the liver. The low Se status did reduce total and reduced glutathione in the liver but did not affect the hepatic malondialdehyde level. In liver phospholipids (PL), Se deficiency significantly reduced levels of palmitic acid [16:0], fatty acids of the n-3 series such as DHA [22:6 n-3], and other long-chain polyunsaturates C-20-C-22, but increased n-6 fatty acids such as linoleic acid (LA) [18:2 n-6]. Thus, the conversion of LA to arachidonic acid was reduced and the ratio of n-6/n-3 fatty acids was increased. As in liver PL, an increase in the n-6/n-3 ratio was also observed in the mucosal total fatty acids of the small intestine. These results suggest that in rats with adequate vitamin E and enhanced fish oil intake, Se deficiency affects the lipid concentration and fatty acid composition in the liver. The changes may be related to the decreased levels of selenoenzymes with antioxidative functions. Possible effects of Se on absorption, storage and desaturation of fatty acids were also discussed. 相似文献
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Herpes Simplex Virus 1-Mediated Transfer of Preproenkephalin A in Rat Dorsal Root Ganglia 总被引:1,自引:0,他引:1
João Manuel Antunes Bras Alberto L. Epstein Sylvie Bourgoin Michel Hamon François Cesselin Michel Pohl 《Journal of neurochemistry》1998,70(3):1299-1303
Abstract: Recombinant herpes simplex virus-1 encoding the rat preproenkephalin A (HSVLatEnk1 ) was generated for driving the expression of preproenkephalin A-derived peptides in dorsal root ganglia of rats in vivo. Three weeks after infection via the hind footpads, quantitative RT-PCR and in situ hybridization experiments showed a strong expression of preproenkephalin A mRNA in lumbar dorsal root ganglia. In addition, a 40–160% increase in radioimmunoassayable Met-enkephalin-like material concentrations was found in the dorsal spinal cord and dorsal root ganglia, respectively, at the lumbar level in HSVLatEnk1 -infected rats as compared with animals infected with β-galactosidase-encoding recombinant herpes simplex virus-1 or control rats. These data demonstrate the efficacy of the preproenkephalin A encoding vector and suggest that it should help in elucidating the role of Met-enkephalin-containing primary afferent fibers in pain transmission and/or control. 相似文献
173.
Theoretical models of cellular dielectrophoresis 总被引:3,自引:0,他引:3
Dielectrophoresis, the motion of neutral particles induced by a non-uniform electric field, is useful in separating and comparing single-celled organisms. The rate of dielectrophoretic collection in a region of higher field, called the “yield”, depends strongly upon the physiological state of the organism, upon the frequency of the field, and upon the conductivity of the suspending medium. The resulting yield spectrum is complex. 相似文献
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Zusammenfassung Das Armverhältnis des spätreplizierenden X-Chromosoms wurde bei 5 Kontrollpersonen, 5 47,XXY Klinefelter-Patienten, 1 46/47,XX/XXX-Mosaik und 1 45/46,X/XX-Mosaik bestimmt. Die statistische Analyse der erhaltenen Werte zeigt, daß die Methode der Armverhältnisbestimmung durch Messung der Armlängen an vergrößert projizierten Chromosomen als geeignet erscheint. Die Mittelwerte der Armverhältnisse der 5 Kontroll-personen können nicht als gleich angesehen werden. Der gesamte Mittelwert der Armverhältnisse ist signifikant kleiner (1,487) für die Klinefelter-Patienten als für die Kontrollpersonen (1,546). Die Werte für die Mosaike XX/XXX (1,557) und XO/XX (1,528) liegen im Bereich der Normalwerte.
Studie im Rahmen des Assoziations-Vertrages Hämatologie EURATOM-GSF Nr.031-64-1 BIAD. 相似文献
Investigations of defining the arm ratio of the late replicating X-chromosome in man
Summary The arm ratio of the late replicating X-chromosome was determined in 5 control persons, 5 47,XXY Klinefelter patients, 1 46/47,XX/XXX mosaic and 1 45/46,X/XX mosaic. The analysis of the values obtained shows that the method of defining the arm ratio by means of measuring arm lengths on drawings of highly magnified projected chromosomes proves practicable. The mean values of the arm ratios of the 5 control persons cannot be valued as equal. The total mean value of the arm ratios is significantly smaller (1.487) for the Klinefelter patients than for the normal control persons (1.546). The values of the mosaics XX/XXX (1.557) and XO/XX (1.528) lie in the range of the control values.
Studie im Rahmen des Assoziations-Vertrages Hämatologie EURATOM-GSF Nr.031-64-1 BIAD. 相似文献
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