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Biomedical subjects

H Takashima

Publications and source records attributed to H Takashima.

At least 199 records · Page 11Linked to original sources
PubMed1984

[An evaluation of radioactive colloid for measuring the volume of effective liver].

A methods for liver scintigraphy for finding the effective liver volume were developed. Matrix ROI (region of interest) was set on the anterior liver scintigram with 99mTc tin colloid and 198Au colloid, respectively. The various depths of liver under matrix ROI were calculated from the count rate noting the absorption coefficient. The effective liver volume was the sum total of the areas of matrix ROI to the various depths. In order to check the accuracy of this method, the effective liver volume was calculated using the liver phantom and the patient's liver scintigraphy. The volume obtained for the liver phantom was nearly equal to the real volume. The liver volume in 19 patients using 99mTc tin colloid and 198Au colloid showed good correlation with the volume as measured by computed tomography (CT) scan (r = 0.841, r = 0.749).

Aged↗
PubMed1983

Structural homology of Torpedo californica acetylcholine receptor subunits.

The nicotinic acetylcholine receptor (AChR) from the electroplax of the ray Torpedo californica is composed of five subunits present in a molar stoichiometry of alpha 2 beta gamma delta (refs 1-3) and contains both the binding site for the neurotransmitter and the cation gating unit (reviewed in refs 4-6). We have recently elucidated the complete primary structures of the alpha-, beta- and delta-subunit precursors of the T. californica AChR by cloning and sequencing cDNAs for these polypeptides. Here, we report the whole primary structure of the gamma-subunit precursor of the AChR deduced from the nucleotide sequence of the cloned cDNA. Comparison of the amino acid sequences of the four subunits reveals marked homology among them. The close resemblance among the hydrophilicity profiles and predicted secondary structures of all the subunits suggests that these polypeptides are oriented in a pseudosymmetric fashion across the membrane. Each subunit contains four putative transmembrane segments that may be involved in the ionic channel. The transmembrane topology of the subunit molecules has also been inferred.

Amino Acid Sequence↗
PubMed1983

Primary structures of beta- and delta-subunit precursors of Torpedo californica acetylcholine receptor deduced from cDNA sequences.

The nicotinic acetylcholine receptor (AChR) from fish electric organ and mammalian skeletal muscle is the best characterized neurotransmitter receptor (reviewed in refs 1-3). The AChR from the electroplax of the ray Torpedo californica consists of five subunits present in a molar stoichiometry of alpha 2 beta gamma delta (refs 4-6); the apparent molecular weights of the alpha-, beta-, gamma- and delta-subunits are 40,000 (40K), 50K, 60K and 65K, respectively. Knowledge of the primary structures of these constituent polypeptides would facilitate the understanding of the molecular mechanism underlying the function of the neurotransmitter receptor. Recently, we have cloned cDNA for the alpha-subunit precursor of the T. californica AChR and have deduced the primary structure of this polypeptide from the nucleotide sequence of the cloned cDNA. Here we report the cloning and nucleotide analysis of cDNAs for the AChR beta- and delta-subunit precursors. The primary structures of the two polypeptides deduced from the cDNA sequences reveal conspicuous amino acid sequence homology among these and the alpha-subunits. The three subunits contain several highly conserved regions which may be essential for the receptor function or inter-subunit interaction.

Amino Acid Sequence↗
PubMed1983

Effects of trichloroethylene exposure on hearing. An investigation of cochlear microphonics and action potential of the guinea pig.

Four groups of guinea pigs with normal Preyer's reflex were exposed to trichloroethylene (TCE). Each group consisted of nine to 10 naive male albino Hartley guinea pigs of 9 weeks of age with a body weight of approximately 400 g. To test the suggestion that TCE causes damage to the cochlear system, a study was conducted involving four experiments. The results were as follows: No significant difference was observed between the intensity functions of the CM (4 kHz) and AP (7 kHz) potentials of the control groups and those of the TCE-exposed groups by analysis of variance. It was considered that there was no difference in the cochlear reaction to high frequency sound between guinea pig and man. It therefore might be suggested that acute exposure to TCE of a high concentration does not always induce dysfunction of the organ of Corti and the 8th nerve in man.

Action Potentials↗
PubMed1983

Active specific immunotherapy using the immune reaction of a low-dose irradiated tumor tissue.

Active specific immunotherapy using the immune reaction of a low-dose irradiated tumor tissue was studied on the transplanted MM46 tumor of female C3H/He mice after radiotherapy. MM46 tumor cells were inoculated into the right hind paws of mice. On the 5th day, irradiation with the dose of 3000 rad was performed. On the 11th day, tumor cells and mononuclear cells, which were separated from the low-dose irradiated tumor tissue (2000 rad on the fifth day), were injected into the left hind paws of the tumor-bearing mice. Effectiveness of this active specific immunotherapy against tumor was evaluated by the regression of tumor and survival rate of mice. Tumor was markedly regressed and survival rate was significantly increased by the active specific immunotherapy.

Adenocarcinoma↗
PubMed1983

[Fundamental and clinical studies of T-1982 (cefbuperazone) in the field of obstetrics and gynecology].

Human pharmacokinetics and clinical studies of T-1982 (cefbuperazone) were carried out and the following results were obtained. Transference into pelvic cavity fluid T-1982 level in pelvic cavity fluid showed the peak level of 48.0 micrograms/ml at 30 minutes after 2 hours drip infusion of 1 g in 1 case. The concentration tended to be more sustained than that of venous blood. Clinical study T-1982 was administered to 2 cases with pelveoperitonitis, 2 cases with puerperal fever and 1 case with adnexitis at a dose of 1 g twice a day for a period of 4 or 5 days. The clinical effect was excellent in 3 and good in 2 cases. Neither side effects nor abnormalities of laboratory findings were observed.

Adolescent↗
PubMed1982

[Fundamental and clinical studies of piperacillin in the field of obstetrics and gynecology].

Human pharmacokinetics and clinical studies of piperacillin (PIPC) were carried out and the following results were obtained. 1. Transference into various uterine tissues PIPC transference into various uterine tissues was 27.3 approximately 67.9% (the ratio with respect to uterine artery blood level) at 1 hour after the completion of PIPC 1 or 2g dripping infusion for 1 hour in 5 cases. 2. Transference into retroperitoneal space exudate PIPC level in retroperitoneal space exudate showed the peak level 38.0 micrograms/ml at 30 minutes after the completion of PIPC 2g dripping infusion for 1 hour in 1 case. The pattern of the concentration trends was more continuous than that of venous blood level. 3. Clinical study We administered PIPC to 5 patients with pelveoperitonitis in 3 cases, puerperal fever in 1 case and wound infection in 1 case at a dose of 4 g per day (twice a day) for a period of 5 approximately 9 days. The clinical effect was excellent in 1, good in 3 and poor in 1 case. Neither side effects nor abnormality of laboratory findings were observed.

Adolescent↗