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91.
Cephalexin and Cephaloglycin Activity In Vitro and Absorption and Urinary Excretion of Single Oral Doses in Normal Young Adults 总被引:3,自引:1,他引:2
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Peter Braun James R. Tillotson Clare Wilcox Maxwell Finland 《Applied microbiology》1968,16(11):1684-1694
A large number of recently isolated bacterial pathogens were tested for susceptibility to cephalexin and cephaloglycin by the replica inoculating method. Strains of group A hemolytic streptococci, viridans (alpha and gamma) streptococci, pneumococci, gonococci, meningococci, and penicillin G-sensitive Staphylococcus aureus were all moderately to highly susceptible to both of these cephalosporin analogues, nearly all of the strains being two to eight (median four) times more susceptible to cephaloglycin than to cephalexin. The penicillin G-resistant, penicillinase-producing strains of S. aureus varied in their susceptibility; many were moderately resistant to both analogues, particularly to cephalexin. Strains of enterococci, Haemophilus influenzae, and most of the common gram-negative bacilli were moderately to highly resistant. Reducing the size of the inoculum had variable effects on inhibition by these drugs, depending on the species or strain. The activity of cephalexin was very little affected by pH of the medium within the clinical range or by incubation at 37 C in broth for up to 24 hr. In contrast, cephaloglycin in broth deteriorated rapidly at 37 C, and its activity was markedly reduced in alkaline medium. Both cephalexin and cephaloglycin were rapidly absorbed and excreted into the urine after single oral doses of 500 mg. Much higher levels were achieved and sustained with the former. Absorption of both analogues was delayed when taken with food, and the levels in the serum were significantly higher and better sustained when probenecid was also given. Very high concentrations of cephalexin were excreted into the urine during the first 4 hr, and the levels were still high in the 4- to 8-hr collection. The concentrations of cephaloglycin in the urine at these times were much lower. An average of 80 to 93% of the dose of cephalexin and 25 to 30% of the cephaloglycin were accounted for as active drug in the urine collected in 8 hr. Both analogues were well tolerated. 相似文献
92.
R Braun 《Biochimica et biophysica acta》1967,149(2):601-603
93.
Analysis of sequential stages in serum bactericidal reactions 总被引:3,自引:0,他引:3
Michael, J. Gabriel (House of the Good Samaritan, Children's Hospital Medical Center, Boston, Mass.), and Werner Braun. Analysis of sequential stages in serum bactericidal reaction. J. Bacteriol. 87:1067-1072. 1964.-The bactericidal reaction of "normal" human serum against Escherichia coli was found to be separable into two distinctive stages. The early (first) stage of the reaction lasts for a relatively short period of time, and involves factors that are present in sufficient amounts only in slightly diluted serum. The later (second) stage needs more time and requires factors present in highly diluted serum. The first stage depends on the presence of Ca(++) and Mg(++) and on the activity of all components of complement; the second stage does not require divalent cations and C'1, C'2, and C'4, but requires factors that can be removed by zymosan. Under our conditions, removal of lysozyme did not influence either stage of the reaction. Bacteria exposed to concentrated serum for a short time, during the first stage, are essentially unaffected as far as their potential for subsequent multiplication is concerned; the actual damage to cellular integrity occurs only during the second stage of the reaction. In the absence of cell division, the "sensitization" produced during the first stage can be preserved for prolonged periods, and the bactericidal reaction can be completed later by exposure to antibody-free, highly diluted serum (second stage). Cell multiplication abolishes the sensitizing effects of the first stage. 相似文献
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98.
Sandra Pannell 《The Australian journal of anthropology》1989,19(3):160-169
…With metaphor we experience the metamorphosis of both language and reality. Paul Ricoeur. ‘Creativity in Language’. The Philosophy of Paul Ricoeur. pp. 132–133 (1973). 相似文献
99.
Sandra Youngman Mansoor Sarfarazi Maja Bucan Marcy MacDonald Barbara Smith Michael Zimmer Conrad Gilliam Anna-Maria Frischauf John J. Wasmuth James F. Gusella Hans Lehrach Peter S. Harper Duncan J. Shaw 《Genomics》1989,5(4)
Genetic linkage studies have mapped Huntington's disease (HD) to the distal portion of the short arm of chromosome 4 (4p16.3), 4 cM distal to D4S10 (G8). To date, no definite flanking marker has been identified. A new DNA marker, D4S90 (D5), which maps to the distal region of 4p16.3, is described. The marker was used in a genetic linkage study in the CEPH reference families with seven other markers at 4p16. The study, together with knowledge of the physical map of the region, places D4S90 as the most distal marker, 6 cM from D4S10. A provisional linkage study with HD gave a maximum lod score of 2.14 at a θ of 0.00 and no evidence of linkage disequilibrium. As D4S90 appears to be located terminally, it should play an important role in the accurate mapping and cloning of the HD gene. 相似文献
100.
Cores were collected from dominant pondcypress trees growing in a swamp that had received sewage effluent for 7 yr and a nearby control swamp to determine the combined effects of changes in nutrient supply and hydrologic regime on tree growth. The cores were used to measure two indices of tree growth: basal area increment (BAI) and relative basal area increment (RBAI, which accounts for differences in growth due to the size of teh tree) between 1970–1983 while one swamp remained untreated and the other received weekly additions of sewage effluent from 1974–1981. Throughout the whole period, the mean BAI and RBAI of pond-cypress trees in the untreated swamp remained unchanged, ranging between 5.55–6.38 cm2 yr–1 and 1.09–1.27% yr–1, respectively. In contrast, trees in the treated swamp increased their BAI approximately two-fold from 7.40 cm2 yr–1 prior to treatment to 14.83 cm2 yr–1 after the onset of treatment and maintained this rate of growth in the 2 yr period after cessation of treatment. Relative basal area increment showed a similar response, but the proportional increase due to treatment was less (1.5-fold factor) than for BAI. The response of pondcypress trees to the sewage effluent differed depending upon whether the trees were located in the deep or shallow water zones. Trees in the deep zone of the treated swamp had lower BAIs and RBAIs than those in the shallow zone during the treatment period, whereas in pre- and post-treatment periods growth indices were equal in both zones. No significant differences in growth between deep and shallow zones were observed during all three time periods in the control swamp. 相似文献