Andreas Back

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We determined the in vitro susceptibilities of 54 isolates of Haemophilus ducreyi from Thailand (29 isolates) and San Francisco (25 isolates) to penicillin G, tetracycline, amoxicillin-clavulanic acid, ceftriaxone, cefixime, erythromycin, azithromycin, ciprofloxacin, ofloxacin, and trimethoprim-sulfamethoxazole. Isolates were susceptible to < or = 0.25(More)
In the past three years cases of shigellosis, amoebiasis, and viral hepatitis A and B have increased fourfold to tenfold in San Francisco. These diseases were most common in people who had adopted "alternative life-styles", especially in young men, In many cases there was a history of frequent orogenital and oral-anal sexual contact between men with no(More)
When kinetin (1 mg/liter) is added to hay infusion medium, the generation time of Paramecium caudatum is shortened immediately upon transfer of the protozoa from stock to isolation culture. Kinetin is particularly effective when culture conditions are suboptimal, perhaps because it substitutes for or supplies some factor which becomes limiting after(More)
It has been suggested that the effect of cytokinins in retarding leaf senescence comes about through their incorporation into tRNA. To test this hypothesis, kinetin-8-(14)C, 6-benzylaminopurine-benzyl-7-(14)C and adenine-8-(3)H were applied to detached tobacco leaves, and the nucleic acids were thereafter extracted and chromatographed on MAK columns.(More)
Envelope, capsid, and soluble antigens of Herpesvirus hominis (HVH) types 1 and 2 were compared to crude antigens (disrupted HVH-infected cells) for potency, type-specificity, and diagnostic value in the indirect hemagglutination (IHA) test. The envelope appeared to be the predominant component reacting in the IHA test, but recurrent HVH infections(More)
Inhibition of the indirect hemagglutination reaction (IHA inhibition) was compared to several other methods for type-specific identification of Herpesvirus hominis (HVH) antibodies and isolates. The method appears to have the greatest value for typing antibodies for HVH type 1 and HVH type 2 in human sera; identification of antibody type was relatively(More)