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101.
Satoshi Shizukuishi Satoshi Nishii John Ellis Karl Folkers 《Biochemical and biophysical research communications》1980,95(3):1126-1130
The mean basal specific activities and the mean % deficiencies of the activity of the glutamic oxaloacetic transaminase of the erythrocytes were identical (n.s.) for a group of eight patients with a severe carpal tunnel syndrome and for a group of eight university students. There was no significant difference in the increases in the specific activities for the patients and the students at 4 concentrations of pyridoxal 5′-phosphate. The apparent Km for the patients and the students was 95 μM and 61 μM (n.s.) respectively. It is concluded from these data in conjunction with previous findings that the carpal tunnel syndrome is a deficiency disease of vitamin B6, which is probably primary rather than one of a dependency state. 相似文献
102.
Genetic analysis of a proposed cis-acting temporal locus ( Adh-3t ), which regulates alcohol dehydrogenase C2 (ADH-C2 ) acitivity in mouse epididymis extracts, among F1 (ddN × BALB/c) × ddN male backcross progeny provided evidence for genetic distinctness between the structural ( Adh-3 ) and temporal ( Adh-3t ) loci on chromosome 3. Genetic analysis also confirmed the close, linkage of Adh-1 (encoding liver and kidney ADH-A2 ) and Adh-3 (encoding stomach ADH-C2 ) to within 0.3 centimorgans on the mouse genome. Evidence is presented for a proposed closely linked cis-acting temporal locus (designated Adh-1t ) for the A2 isozyme (encoded by Adh-1 ) controlling the activity of this enzyme in mouse kidney extracts, but having no apparent affect on liver and intestine ADH-A2 activities. An extensive survey of the distribution of Adh-1, Adh-3 and Adh-3t alleles among 65 strains of mice is reported — with the exception of two Japanese strains (ddN and KF), linkage disequilibrium between Adh-3 and Adh-3t was observed. Sex differences in mouse liver and kidney ADH-A2 activities were observed, with male/female ratios of approximately 0.6 and 3 respectively for these tissue extracts. 相似文献
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Rudi Berera Ivo H.M. van Stokkum Sandrine d'Haene John T.M. Kennis Rienk van Grondelle Jan P. Dekker 《Biophysical journal》2009,96(6):2261-2267
When grown under a variety of stress conditions, cyanobacteria express the isiA gene, which encodes the IsiA pigment-protein complex. Overexpression of the isiA gene under iron-depletion stress conditions leads to the formation of large IsiA aggregates, which display remarkably short fluorescence lifetimes and thus a strong capacity to dissipate energy. In this work we investigate the underlying molecular mechanism responsible for chlorophyll fluorescence quenching. Femtosecond transient absorption spectroscopy allowed us to follow the process of energy dissipation in real time. The light energy harvested by chlorophyll pigments migrated within the system and eventually reaches a quenching site where the energy is transferred to a carotenoid-excited state, which dissipates it by decaying to the ground state. We compare these findings with those obtained for the main light-harvesting complex in green plants (light-harvesting complex II) and artificial light-harvesting antennas, and conclude that all of these systems show the same mechanism of energy dissipation, i.e., one or more carotenoids act as energy dissipators by accepting energy via low-lying singlet-excited S1 states and dissipating it as heat. 相似文献
106.
John E. Hobrough 《Hydrobiologia》1973,41(1):13-35
Two inlet streams, Rostherne Brook and the Southern Drain of Dolls Meadow, flowing into Rostherne Mere, Cheshire were sampled for macroinvertebrata, and their physical and chemical conditions analysed.The physical and chemical factors for these streams were similar, except for the stream beds and the pollution of Rostherne Brook. Both streams had large populations of Gammarus pulex and the life history of this organism was studied. The ratio of adult organism to juvenile diflered in the two streams, Rostherne Brook having a higher proportion of adults in winter and juveniles in summer as opposed to the Southern Drain in which a normal life history was exhibited.Experiments showed that these differences were not related to differences in stream bed conditions. It was considered that the different adult to juvenile ratios were therefore caused by pollution in Rostherne Brook. The juveniles were more tolerant to pollution and therefore more able to survive the summer when pollution effects were at a maximum.The life history was altered in Rostherne Brook by pollution. Instead of the dual life history produced by overwintering juveniles and speedy summer maturation, a simple alternation of juveniles and adults was seen.This change in life history enabled Gammarus to survive in the polluted waters of Rostherne Brook.
Resume Deux débouchés de ruisseaux, Rostherne Brook et le Southern Drain de Doll's Meadow, qui coulent tous les deux dans le lac de Rostherne dans le Cheshire, ont été échantillonnés pour y trouver des macroinvertébrés, et pour en analyser les conditions physiques et chimiques.On a trouvé semblables les éléments physiques et chimiques de ces ruisseaux, à l'exception du lit des deux ruisseaux et de la pollution de Rostherne Brook.Les deux ruisseaux avaient une population nombreuse de Gammarus pulex dont on a étudié le cycle d'évolution. On a trouvé une proportion différente d'organismes adultes et jeunes dans les deux ruisseaux: Rotherne Brook a une plus grande proportion d'adultes en hiver et de jeunes en été, pendant que Southern Drain montre un cycle normal des organismes.Des expériences ont prouvés que ces différences n'avaient aucun rapport à des différences de conditions du lit des ruisseaux. On a considéré que la pollution de Rostherne Brook a donc causé les proportions différentes d'adultes et de jeunes. Les jeunes toléraient mieux la pollution et pouvaient donc mieux survivre à l'été quand les effets de la pollution étaient au maximum.Le cycle d'évolution était changé dans Rostherne Brook par la pollution. Au lieu du double cycle d'évolution produit par les jeunes qui passaient l'hiver et par un développement rapide en été, on a découvert uniquement l'alternation de jeunes et d'adultes.Ce changement du cycle d'évolution a permis au Gammarus de survivre dans les eaux corrumpues de Rostherne Brook.相似文献
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