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Biomedical subjects

A Okubo

Publications and source records attributed to A Okubo.

At least 91 records · Page 5Linked to original sources
PubMed1986

Dynamical aspects of animal grouping: swarms, schools, flocks, and herds.

Grouping of animals is a natural phenomenon in which a number of animal individuals are involved in movement as forming a group. Examples are insect swarms and fish schools. In this article an attempt is made to describe the motion of grouping individuals kinematically as distinct from simple diffusion or random walk, to model the grouping on the basis of dynamics of animal motion, and to interpret the grouping from the standpoint of advection-diffusion processes. Also presented is dynamical modeling for the group size distribution as a result of amalgamation and splitting processes of groups. Examples of animal grouping are described in detail. They are insect swarms, zooplankton swarms, fish schools, bird flocks, and mammal herds. The presented mathematical models are compared with data of these animal groupings.

Animals↗
PubMed1986

31P nuclear magnetic resonance analysis of lung cancer: the perchloric acid extract spectrum.

31P-NMR spectra were obtained from the perchloric acid extracts of normal lung and lung cancer tissues obtained at surgery, and from extracts of neoplastic cells cultured in vitro. The perchloric acid extract of lung cancer tissue gave rise to a signal whose chemical shift was 3.2 ppm at pH 8.0. This signal was not observed in the extract of normal tissue of the lung from the same patient. The compound giving this signal was identified as phosphorylcholine.

Adenoviridae↗
PubMed1983

Primary hepatocellular carcinoma and IgG heavy chain allotypes.

We studied Gm typing of serum samples from 838 donors; 177 had chronic hepatitis, 166 liver cirrhosis, 113 primary hepatocellular carcinoma, 21 alcoholic hepatitis, 18 fatty liver and 343 were unrelated normal blood donors. The distribution of Gm phenotypes and haplotypes in sera from patients with primary hepatocellular carcinoma differed from that in the normal controls; the Gm phenotype (1,2,21,13,15,16) and the haplotype Gm1,2,21 were significantly more common in this patient group (X2 = 18.56, corrected P less than 0.01, relative risk = 3.12; X2 = 25.52, corrected P less than 0.005, respectively). Overall, in the other liver diseases, we observed no significant Gm phenotype or haplotype association. The commitment to progression to primary liver carcinoma seems to be ascribable to a gene or polygenes close to the IgG heavy chain loci.

Carcinoma, Hepatocellular↗