Search PubMed⌕ Search

Biomedical subjects

T Kihara

Publications and source records attributed to T Kihara.

At least 181 records · Page 10Linked to original sources
PubMed1979

Rates of reduced cytochrome c-ferricyanide binding and electron transfer.

The oxidation of reduced cytochrome c by ferricyanide has been studied over a wide range of ferricyanide concentrations using a continuous-flow apparatus. The formation of a ferrocytochrome c-ferricyanide complex has been demonstrated and the binding and electron transfer processes separated to give both the oxidation electron transfer rate and the binding rate parameters. The electron transfer rate has been found to be 1.86 . 10(3) s-1 in H2O buffer and 1.36 . 10(3) s-1 in 2H2O demonstrating that a deuterium isotope effect of similar magnitude (R = 1.37) to that found in the cytochrome reactions in photosynthetic bacteria [18] is also found in the reaction studied here. The binding association rate parameters also show a similar deuterium isotope effect suggesting that water rotation may be involved in both the binding of ferricyanide to reduced cytochrome c and the subsequent oxidation electron transfer.

Animals↗
PubMed1977

Effect of prenatal treatment with ethinyl estradiol on the mouse uterus and ovary.

Oral ethinyl estradiol (0.01 or 0.02 mg. per kilogram) administered prenatally to ICR-JCL strain mice before the development of the uterine and ovarian blastemata induced cystic glandular hyperplasia with epidermization in the endometrium and excessive formation of degenerating follicles in the ovaries at 10 to 14 weeks of age. To the evidence for the production by estrogen of malignant uterine neoplasms in rodents and the clinical data showing that cystic glandular hyperplasia develops after prolonged estrogen administration in postmenopausal women and adenocarcinoma in premenopausal or menopausal women using oral contraceptives including ethinyl estradiol, we add the present results which suggest that ethinyl estradiol administered transplacentally can cause malignant transformation of the uterine endometrium in mice.

Animals↗
PubMed1976

Doses to critical organs from dental radiography.

Participants in the jointly sponsored Atomic Bomb Casualty Commission and Japanese National Institute of Health (ABCC-JNIH) Adult Health Study, a fixed-population sample under continual observation for late effects of the atomic bombs, are also being evaluated for their exposure to other sources of ionizing radiation. In the present study, the subjects' thyroid, lens, pituitary, bone marrow, and gonadal doses acquired during dental radiography were estimated from dosimetry of simulated human material exposed according to technical factors as ascertained in previously reported surveys of patients, dental clinics and hospitals, and dosimetry with phantom human material containing lithium fluoride thermoluminescence dosimeters and ionization chambers. Dental radiography comprised a relatively small segment of the contaminating sources of ionizing radiation exposure among this population sample. Efforts should be made to improve exposure conditions, especially in view of the increasing frequency of dental x-ray examinations.

Head↗
PubMed1976

The distribution of 14c from [U-14c]glucose in mice using whole-body autoradiography.

Tissue distribution of radioactive carbon from [U-14C]glucose in the mouse in vivo was studied by whole-body autoradiography. The mice were frozen with Dry-Ice-acetone at 0.5, 1, 5 and 30 min, 1 and 24 hr and 1 and 3 weeks after intraperitoneal injection of [U-14C]glucose. Whole-sagittal sections of the frozen mouse, obtained by using a microtome in a cryostat, were dried in a cryostat and autoradiographed. The resulting dry autoradiographs are called untreated autoradiographs in the present work. The sections were then fixed in cold 6% (w/v) HClO4, dried at room temperature and again autoradiographed. Autoradiographs that have undergone this process are referred to as treated autoradiographs. In both untreated and treated autoradiographs, within 1 min following injection of the labeled glucose, the abdominal cavity had the highest autoradiographic density. At 1 hr, density became highest in Harder's, sublingual and duodenal glands, large intestinal mucosa and tongue, and after 3 weeks, no autoradiographic denisty was present.

Adipose Tissue, Brown↗
PubMed1976

The chemistry of actinocarcin. I. Further characterization and C-terminal structure of actinocarcin.

The amino-acid composition and molecular weight of actinocarcin, and C-terminal structure of actinocarcin are reported in this paper. By STEIN-MOORE'S and ultraviolet-absorption methods, the molar ratio of amino acids in actinocarcin was determined. The N-terminal amino acids are alanine and valine. The C-terminal amino acid, determined by hydrazinolysis, is tryptophan. The molecular weight is about 11,000 as estimated by ARCHIBALD'S method and amino acid analysis. Three fragments, named BrCN-I, BrCN-II and BrCN-III, were obtained by cyanogen bromide cleavage. The structure of BrCN-III, namely the C-terminal structure of actinocarcin was determined by EDMAN degradation.

Amino Acids↗