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1.
A tetrazolium-based microphotometric method has been devised for the determination of structure-bound dehydrogenase activities
with correction for nothing-dehydrogenase artefacts. The method is based on the microphotometric recording of maximum reaction
rates in a simple incubation chamber and consists of two successive measurements on the same section, the first in the absence
and the second in the presence of the substrate. Following the first measurement, the substrate-free medium is quickly exchanged
with the substrate-containing medium and a second measurement is taken. Subtraction of the first from the second reaction
rate yields the enzyme activity corrected for nothing-dehydrogenase. Measurements of succinate dehydrogenase (SDH) in skeletal
muscle fibres, liver, cardiac atrium and ventricle demonstrate the feasibility of the method. Measurements on the extensor
digitorum longus muscle of rat reveal a range of up to fivefold differences in SDH activity within the fibre population of
this muscle.
Accepted: 11 April 1997 相似文献
2.
A dominant mutation, responsible for the resistance to oxythiamin inSaccharomyces cerevisiae was mapped on the right arm of chromosome IV, 4.6 cM centromere-distally totrp1. The corresponding gene is not involved in the control of intracellular content of total thiamin during growth on a minimal
medium without thiamin. 相似文献
3.
Brigitta M. N. Brinkman Eric L. Kaijzel Tom W. J. Huizinga Marius J. Giphart Ferdinand C. Breedveld Cornelis L. Verweij 《Human genetics》1995,96(4):493-493
We have identified a C-insertion polymorphism in the 5'UTR of the first exon of the human tumor necrosis factor alpha (TNFA) gene. TNFA is a cytokine that plays an important role in the inflammatory response. 相似文献
4.
F. Šrámek 《Biologia Plantarum》1999,42(4):582-582
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7.
Ferdinand Bohlmann Elena Tsankova Jasmin Jakupovic Robert M. King Harold Robinson 《Phytochemistry》1983,22(2):557-560
The investigation of Encelia canescens afforded, in addition to several known compounds, four new dimeric p-hydroxyacetophenone derivatives, two epimeric chromene dimers and two epimeric mixed dimers of euparin and encecalin. Furthermore, derivatives of tremetone and of encecalin were present. The structures were elucidated hy high field 1H NMR spectroscopy. 相似文献
8.
We studied 630 bacterial strains isolated from surface waters and determined as enterococci on the basis of their growth on
Slanetz-Bartley agar in typical colonies. The strains were tested and characterized by several key conventional tests for
basic differentiation of enterococci and by commercial test kits. We identified 135 strains ofE. fœcium (21%), 115E. fœcalis (18%), 30E. mundtii (5%), 27E. hirae (4%), 22E. casseliflavus (3%), 21E. gallinarum (3%), 17E. durans-E. hirae complex (3%), 5E. durans (1%), and 1 strain ofE. avium. 150 strains were classified only asEnterococcus sp. (25%) and 107 strains (17%) isolated from Slanetz-Bartley agar were not enterococci. We found that the non-enterococcal
group consisted of other Gram-positive cocci and Gram-positive and Gram-negative rods. Based on the identification we tried
to find a relation between taxonomic position of isolated strains and their colony morphology on Slanetz-Bartley agar. Out
of the total of 523 identified enterococci, 345 strains (66%) formed purple colonies, 136 red colonies (26%), 37 pink colonies
(7%) and 5 cream colored colonies (1%). There was no correlation among the color, size or colony morphology and the taxonomic
characterization of enterococcal strains. 相似文献
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10.