摘要:

The data obtained by applying the pharmacokinetic theory of Krüger-Thiemer to a tetracycline antibiotic administered in the pediatric age are set forth. In particular, the results obtained by interpolation are compared with those actually observed, and the values of the constants of absorption and elimination of the antibiotic, its apparent value of distribution and its half-life are calculated

ISSN:0009-3157    

DOI:10.1159/000220709

出版商:S. Karger AG    

年代:1971

数据来源: Karger

摘要:

Thirty strains of Cl. perfringens isolated from clinical material were found to be inhibited in vitro by 3 μg/ml or less of cephalothin and cephaloridine, 12 μg/ml or less of cephalexin and 6 μg/ml or less of cephaloglycin, as determined with the agar and microtiter broth dilution techniques. Cephaloridine appeared somewhat more active than cephalothin and cephaloglycin, while cephalexin appeared to be slightly less active than the former 3 cephalosporins, on a weight-for-weight basis. With few exceptions, the MBC’s of all 4 cephalosporins either coincided with or were twofold higher than the corresponding M

ISSN:0009-3157    

DOI:10.1159/000220710

出版商:S. Karger AG    

年代:1971

数据来源: Karger

摘要:

Carbenicillin, a recently introduced semi-synthetic penicillin, has a relatively high activity against Pseudomonas aeruginosa. A marked inoculum effect on the minimum inhibitory concentration has been recorded. A number of in vitro experiments have been carried out with four Pseudomonas aeruginosa strains. No enzymatic degradation of carbenicillin has been noted not even after induction with penicillin G and carbenicillin. The strains rapidly degraded penicillin G and ampicillin. Variants with decreased sensitivity, 8 to 32 times that of the original population, could be found after a number of transfers in liquid substrates containing increasing concentrations of carbenicillin. These variants proved stable and they were unable to break down carbenicillin. By using viable counts it has been shown that variations in inocula do not influence the MIC value when this is defined as the smallest concentration of antibiotic just inhibiting an increase in viable counts after inoculation. Employing large inocula, an initial bacteriostatic effect of carbenicillin is recorded.

ISSN:0009-3157    

DOI:10.1159/000220711

出版商:S. Karger AG    

年代:1971

数据来源: Karger

摘要:

1-β-D-arabinofuranosylcytosine (ara-C) therapy (60mg/kg i. p. once daily) in mice causes a pronounced and rapid effect of short duration on the cytopoietic mechanism of the marrow. Of the blood elements, long-term effects were seen for the platelets. A striking effect of ara-C therapy was that of a hemoconcentration, which occurred early after treatment and was very temporary in nature. Being related to body weight loss suggests that this is due to dehydration, and not a hematological effect per se. In general, ara C’s hematological toxicity in the mouse has been found to resemble that reported in human studies. The finding that ara-C produces a cessation of normoblast production agrees well with its efficacy in the treatment of polycythemia vera and with erythrokinetic data. Although ara-C is known to rapidly induce megaloblastosis in man, no megaloblasts could be found in the marrows of mice treated with this agent, which agrees with other evidence indicating that the mouse is incapable of megaloblastosis. The pathogenesis of megaloblastosis is discussed in reference to ara-C’s capacity to produce an ‘unbalanced growth’. Deoxycytidine (100 mg/kg s. c. once daily), administered concurrently with ara-C, prevented all of the above effects of ara-C therapy. In the case of the platelets, however, a return to normal was, as compared to the erythroid and myeloid elements, somewhat delayed. The use of more drastic dosage schedules of ara-C, both for systemic and local tumor therapy, under continuous marrow protection with deoxycytidine, is recommended for furth

ISSN:0009-3157    

DOI:10.1159/000220712

出版商:S. Karger AG    

年代:1971

数据来源: Karger

摘要:

Proliferating cultured leukemia L1210 cells exposed to cytotoxic concentrations of actinomycin D, daunomycin, or mitomycin C are killed at a rate which is relatively dependent upon the concentrations used. On an equimolar basis, proliferating L1210 cells are equally sensitive to actinomycin D or daunomycin and are the least sensitive to mitomycin C. Nonproliferating L1210 cells are sensitive to these agents in vitro. The nonproliferating cells are the most sensitive to actinomycin D, less sensitive to daunomycin, and the least sensitive to mitomycin C. A comparison of the sensitivity of proliferating and nonproliferating L1210 cells to these agents indicate that proliferating cells are more sensitive than nonproliferating cells. The results of this study indicate that actinomycin D, daunomycin, and mitomycin C are neither cell-cycle-specific nor cell-cycle-stage-specific agents. This implies (a) that these drugs may be potentially effective in treating malignancies with low growth fractions and (b) that effective therapy with these agents may be enhanced by increasing the dosage up to the limits of acceptable toxicity to normal tissues.

ISSN:0009-3157    

DOI:10.1159/000220713

出版商:S. Karger AG    

年代:1971

数据来源: Karger

ISSN:0009-3157    

DOI:10.1159/000220714

出版商:S. Karger AG    

年代:1971

数据来源: Karger

ISSN:0009-3157    

DOI:10.1159/000220757

出版商:S. Karger AG    

年代:1971

数据来源: Karger