Search

Several fixed point theorems for multi-valued global and local contraction mappings are proved. These results concerning contractions are then applied to obtain a fixed point theorem for a certain type of single-valued locally expansive mapping.

SummaryMouse ascites tumor cells exposed to specific anti-sera in the presence of complement failed to concentrate and incorporate labeled amino acid into gross cellular protein. Inhibition of amino acid uptake by specific anti-sera closely parallels cell rupture by anti-sera (in the presence of complement) and this appears to be a rapid and sensitive biochemical assay for antibody produced against mouse ascites tumor cells by the rat.

SummaryRadioactive 9-B-6-MP-S35 and 9-E-6-MP-S35 were synthesized and administered to patients. The radioactive metabolites in the urine were separated on Dowex 1-X8 columns and identified by spectrophotometric and chemical analysis. 50 to 70% of the drugs was excreted as the S-glucuronide. About 15% of each drug was excreted in unaltered form. While no other major metabolite was found in urine of patients given the 9-butyl derivative, urine from patients given 9-E-6-MP-S35 contained small amounts of radioactive substance having a spectrum similar to thioxanthine, and a larger amount having a spectrum characteristic of thiouric acid. The significance of these observations is discussed.

SummaryOsgood's tissue culture J-128 may be cultured on a simple medium which does not contain preformed purine or AIC. When hypoxanthine or AIC are added to the culture medium the cells utilize th...

SummaryEvidence was presented that 9-E-6-MP is dealkylated by the human in amounts adequate to provide enough 6-MP to explain the effectiveness of this drug when it is administered to chronic granulocytic leukemia patients. 9-E-6-MP does not serve as substrate for xanthine oxidase, nor purine nucleoside phosphorylase. The possibility that the enzyme responsible for dealkylation is present in human bone marrow or neutro-phils is discussed.

The following lemma, which appears as Lemma 4 in [5], was used to determine certain multicoherence properties of inverse limits of continua.Lemma. Let X denote the inverse limit of an inverse system {Xλ, fλμ, Λ} of compact Hausdorff spaces Xλ. If Xλ has no more than k components (where k < ∞ is fixed) for each λ ∊ Λ, then X has no more than k components.In this paper we give a set theoretic analogue of this lemma and an extension which was suggested to the author by Professor F. W. Lawvere. An application to inverse limits of finite groups is then given.

(1973). The Indecomposability of the Dyadic Solenoid. The American Mathematical Monthly: Vol. 80, No. 6, pp. 677-679.