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121.
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123.
Primary structure of the vitamin K-dependent part of prothrombin 总被引:23,自引:0,他引:23
124.
Synthesis of polyoma DNA by isolated nuclei 总被引:7,自引:0,他引:7
125.
Characterization of a pleiotropic succinate dehydrogenase-negative mutant of Bacillus subtilis 总被引:4,自引:0,他引:4
A succinate dehydrogenase-negative mutant of Bacillus subtilis is described which lacks all three subunits of the membrane-bound succinate dehydrogenase complex: flavoprotein, iron protein, and cytochrome b558. The corresponding mutation is revertible and it maps at one extreme of the sdh region. The results presented suggest that the structural genes for the subunits of the succinate dehydrogenase complex are part of one operon. 相似文献
126.
Overproduction of outer membrane protein suppresses envA-induced hyperpermeability. 总被引:5,自引:3,他引:2 下载免费PDF全文
A quantitative study on outer membrane components was performed in a number of envelope mutants of Escherichia coli K-12 exhibition different permeability properties for antimicrobial agents. The envA1 allele causing an increased influx for both hydrophobic and hydrophilic drugs was found to be associated with a deficiency in the amount of lipopolysaccharides. The sefA1 envA1 double mutant was found to have a higher outer membrane buoyant density, apparently due to an increase in protein content. This double mutant was still low in lipopolysaccharide content. 相似文献
127.
The activity of MAO-A and MAO-B in four different brain regions (striatum, limbic system, occipito-temporal cortex and hemispheres) was determined after hemitransection of the left side. There was no difference in the MAO-A activities of either the left or right sides of the brain in either control or hemitransected rats. The activity of MAO-B was the same for both sides in control rats, but there was an increased MAO-B activity in the left side of the hemitransected rats with respect to the right side in all brain regions investigated, with the possible exception of the limbic system. The increase was due to a change in the Vmax rather than to a changed Km of the MAO-B. The interaction of the MAO-B with oxygen was unchanged after hemitransection. 相似文献
128.
Hydroxyurea-Induced Accumulation of Short Fragments During Polyoma DNA Replication II. Behavior During Incubation of Isolated Nuclei 总被引:7,自引:3,他引:4 下载免费PDF全文
G?ran Magnusson 《Journal of virology》1973,12(3):609-615
The synthesis of polyoma DNA was studied in isolated nuclei from hydroxyurea-inhibited 3T6 cells infected with polyoma virus. During incubation of nuclei under conditions suitable for polyoma DNA synthesis in vitro, the short DNA fragments with a sedimentation coefficient of 4S formed in vivo (hydroxyurea fragments) became associated with preformed, replicating DNA strands. Centrifugation in dye-buoyant density gradients showed that the fragments formed part of the structure of the replicative intermediate of polyoma DNA. The proportion of "young" replicative intermediates was larger after hydroxyurea inhibition than in uninhibited controls. Hydroxyurea fragments appear to be closely related to the 4S fragments formed as normal intermediates during discontinuous synthesis of polyoma DNA. 相似文献
129.
R.T. Zahradnik I. Magnusson C. Walker E. McDonell C.H. Hillman J.D. Hillman 《Journal of applied microbiology》2009,107(2):682-690
Aims: To conduct a pilot human clinical trial to assess the safety and to test the ability of a probiotic mouthwash, ProBiora3 , to affect the levels of Streptococcus mutans and certain known periodontal pathogens in the mouth when administered twice daily over a period of 4 weeks.
Methods and Results: The mouthwash contained three specific strains of naturally occurring oral bacteria and was tested at two dose levels: 106 and 108 colony forming units each of Strep. oralis strain KJ3sm, Strep. uberis strain KJ2sm, and the spontaneous lactic acid-deficient variant of Strep. rattus , strain JH145. Substantial decreases in the levels of the marker bacteria were observed. No safety issues were noted with the twice daily application of this mouthwash.
Conclusions: Despite the small number of subjects and the use of young, orally healthy adults, along with the inherent variability in the microbiological measurements, the probiotic mouthwash was able to substantially affect the levels of dental pathogens in saliva and periodontal pathogens in subgingival plaque.
Significance and Impact of the Study: The results of this pilot human study suggest that the probiotic mouthwash product may be safe for daily use as an aid in maintaining both dental and periodontal health. 相似文献
Methods and Results: The mouthwash contained three specific strains of naturally occurring oral bacteria and was tested at two dose levels: 10
Conclusions: Despite the small number of subjects and the use of young, orally healthy adults, along with the inherent variability in the microbiological measurements, the probiotic mouthwash was able to substantially affect the levels of dental pathogens in saliva and periodontal pathogens in subgingival plaque.
Significance and Impact of the Study: The results of this pilot human study suggest that the probiotic mouthwash product may be safe for daily use as an aid in maintaining both dental and periodontal health. 相似文献
130.
Björn J. Gosch Nicholas A. Paul Rocky de Nys Marie Magnusson 《Journal of applied phycology》2015,27(4):1607-1622