Publications by authors named "Ullrich R"

Reassociation kinetics and electron microscopy were used to examine the organization of DNA sequences in the Basidiomycete Schizophyllum commune. Short-period interspersion of repetitive and unique sequences is absent from the DNA of this wood-rotting fungus. Instead, repetitive sequences are found predominantly in several, perhaps 16, clusters averaging 225 kilobases in length.

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A study of nursing personnel in a private general hospital suggests that the high rate of turnover results as much from dissatisfaction with intrinsic job factors as from dissatisfaction with extrinsic factors. These findings contradict the Herzberg two-factor theory, and suggest alternative means of improving management of nurses.

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A new functional class of nucleic acids is postulated on the basis of the multiallelic incompatibility system regulating sexual morphogenesis in the higher fungi. A physical-chemical basis for distinguishing molecules active, as opposed to inactive, in promoting morphogenesis is established by the secondary structure of the resultant nucleic acid duplexes. This regulatory mechanism may be of broad import.

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The antitumor properties of Corynebacterium parvum have been studied in young (3- to 8-month-old) and aged 18 or more months old) BALB/c mice given s.c., i.

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The wood-rotting basidiomycete, Sistotrema brinkmannii, is an aggregate of biological species possessing several variations-homothallism, bipolar heterothallism and tetrapolar heterothallism-on the genetic regulation of a critical phase of development. Nutritionally forced intra- and interspecific matings provide genetic information about the relatedness of homothallic isolates, the relation of the various species to one another, the genetic basis of homothallism, and its relationship to heterothallism. Most homothallic isolates are interfertile when nutritionally forced.

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