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101.
Hervé Seitz 《Current biology : CB》2010,20(3):R108-R110
102.
Berta Fiszer-Szafarz David Szafarz Alba Guevara de Murillo 《Analytical biochemistry》1981,110(1):165-170
A fluorometric method using 3,5-diaminobenzoic acid for DNA determination in tissues, cultured cells, nucleated blood cells, and yeast cells is described. The method is general, simple, and rapid, and does not require prior DNA extraction, since tissue is directly solubilized in Triton X-100 and ammonia. The procedure is highly sensitive, and is able to measure rather accurately as little as 10 ng of DNA. It is applicable to all types of DNA structure. The DNA content determined in various tissues and cells was: 2.50 mg/g fresh rat liver, 3.32 mg/g rat diethylnitrosamine-induced hepatoma, 2.49 mg/g fresh mouse liver, 8.76 μg/106 human leukocytes, 3.37 μg/106 chicken fibroblasts, 2.97 μg/108 haploid yeast cells, and 2.84 μg/108 haploid yeast protoplasts. 相似文献
103.
Production of vanillic acid from vanillin by resting cells of Serratia marcescens. 总被引:2,自引:2,他引:0 下载免费PDF全文
Resting-cell suspensions of Serratia marcescens were able to convert, quantitatively, 0.3% vanillin to vanillic acid. The vanillic acid-producing activity reached a maximum after 28 h of incubation with 0.01% vanillin as an inducer. 相似文献
104.
Wytske de Vries M. I. H. Aleem Anneke Hemrika-Wagner A. H. Stouthamer 《Archives of microbiology》1977,112(3):271-276
Fumarase-free electron particles from Propionibacterium freudenreichii and P. pentosaceum were prepared by discontinuous sucrose gradient centrifugation, and the influence of 2-n-heptyl-4-hydroxy-quinoline-N-oxide (HQNO) and ultraviolet irradiation on the reduction of menaquinone and cytochrome b with l-lactate or glycerol-3-phosphate and the reoxidation by fumarate was studied. In the presence of HQNO the steady state reduction level of menaquinone during fumarate reduction was increased whereas the steady state reduction level of cytochrome b was decreased as compared with the reduction levels measured in the absence of HQNO. The steady state reduction level of menaquinone during electron transport to fumarate was not influenced by ultraviolet irradiation and the steady state reduction level of cytochrome b was decreased at increasing irradiation times. The data indicate that cytochrome b is involved in the electron transport to fumarate.Abbreviations HQNO
2-n-heptyl-4-hydroxyquinoline-N-oxide
- NQNO
2-n-nonyl-4-hydroxyquinoline-N-oxide
Visiting Professor at the Biological Laboratory 相似文献
105.
106.
The improvement of glass capillary preparation technology has allowed the development of high-resolution and very low-bleeding gas chromatographic columns. Using an all-glass injector and a flame ionization detector, it was possible to get a complete resolution of some of the principal stable oxygenated metabolites of arachidonic acid (cyclized and aliphatic, i.e., eicosanoids). Due to the low bleeding of the column, detector limits exceed those obtained with previously prepared columns. Total profiling studies have been obtained with small amounts of activated washed platelets after only an ether extraction, allowing for the first time a complete, simultaneous survey of cycloxygenase and lipoxygenase pathways. The application has been extended with success to other cell types. 相似文献
107.
108.
How often will elections end in landslides? What is the probability for a head-to-head race? Analyzing ballot results from several large countries rather anomalous and yet unexplained distributions have been observed. We identify tactical voting as the driving ingredient for the anomalies and introduce a model to study its effect on plurality elections, characterized by the relative strength of the feedback from polls and the pairwise interaction between individuals in the society. With this model it becomes possible to explain the polarization of votes between two candidates, understand the small margin of victories frequently observed for different elections, and analyze the polls'' impact in American, Canadian, and Brazilian ballots. Moreover, the model reproduces, quantitatively, the distribution of votes obtained in the Brazilian mayor elections with two, three, and four candidates. 相似文献
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