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Biomedical subjects

I Watanabe

Publications and source records attributed to I Watanabe.

At least 343 records · Page 19Linked to original sources
PubMed1987

Immunoelectron microscopy for growth hormone and prolactin in pituitary adenomas.

Growth hormone (GH)- and prolactin (Prl)-producing pituitary adenomas were studied with immunoelectron microscopy using protein A-gold complex, and were compared with the normal pituitary gland. GH-producing cells were readily identifiable by numerous, uniformly dense, round secretory granules in both adenomas and normal pituitary gland. In contrast, Prl secretory granules in normal pituitary gland were much larger in size than the scarce, smaller, secretory granules of Prl-producing adenomas. Thus immunoelectron microscopic identification of Prl is more valuable for prolactinoma. With more specific antigens available as tumor markers, immunoelectron microscopy appears to be a powerful tool for tumor diagnosis.

Adenoma↗
PubMed1987

Surgical approach to tumors arising from the posterior two thirds of the nasal septum.

A surgical approach to tumors of the septum is discussed. Two patients who had tumors in the posterior two thirds of the septum are shown in this paper. One had a benign mixed tumor and the other had an extramedullary plasmacytoma in the posterior two thirds of the septum. They underwent resection of the tumors with the septum by lateral rhinotomy. The first case additionally underwent an oval-shape resection of the palate. The postoperative profiles of the nose are good.

Female↗
PubMed1987

Sonotubometric measurement of the eustachian tube function by means of band noise. A clinical view of the acoustic measurement of the eustachian tube.

The Eustachian tube is well known as an organ serving the ventilation and drainage of the tympanic cavity and mastoid. Ventilation is carried out by the opening and closing of the Eustachian tube accompanying swallowing movements. Until now there has been no instrument to quantify these motor activities of the tube necessary for its function as a ventilator. The author developed a generally applicable sonotubometer Model WIO-01 with the help of Siemens Hearing Institute K.K. for automatic measurement of the aforesaid tubal function with the use of 7 kHz full-octave band noise. In a sonotubometric trial with 32 adult female subjects, the duration of patency of the Eustachian tube was 288.5 +/- 1.38.5 ms, and the amplitude eliciting response was 16.4 +/- 8.3 dB. The positive response rate was 89.1%. In 89 children aged 4-12 years, a positive response was detected in 117 ears (61.9%). The mean duration of patency was 337.7 +/- 154.4 ms, and the amplitude 16.3 +/- 7.2 dB. It is physiological to have tubal opening and closing during natural swallowing. It is therefore important to understand the tubal function when dealing with tympanoplasty and diseases caused by tubal dysfunction.

Acoustic Stimulation↗
PubMed1987

Effect of graded coronary flow reduction on ionic, electrical, and mechanical indexes of ischemia in the pig.

This study was performed to determine the relative sensitivities of ionic, electrical, and mechanical indexes of myocardial ischemia. We used ion-selective and bipolar plunge electrodes, epicardial unipolar electrodes, a suction electrode, and ultrasonic crystals to determine the changes in intramyocardial extracellular potassium ([K+]e) and extracellular pH (pHe), local activation, epicardial TQ-ST segment, monophasic action potential duration (MAPD), and regional contractility during graded coronary flow reduction in open-chest pigs. A carotid-to-coronary shunt was created to perfuse the left anterior descending coronary artery via a roller pump. The shunted coronary flow was reduced in a stepwise fashion at 5-min intervals. In 25 pigs, the approximate myocardial blood flow associated with the initial changes in each variable was as follows: midmyocardial [K+]e, pHe, and TQ-ST segment, 0.7 to 0.8 ml/min/g; subepicardial [K+]e and TQ-ST segment, 0.6 to 0.7 ml/min/g; segmental shortening, 0.5 to 0.6 ml/min/g; local activation and epicardial TQ-ST segment, 0.3 to 0.4 ml/min/g; epicardial MAPD, 0.15 to 0.2 ml/min/g. Our results indicate that changes in [K+]e, pHe, and TQ-ST segment provide the most sensitive means of detecting myocardial ischemia and of determining the effect of interventions capable of influencing the ischemic process.

Action Potentials↗
PubMed1987

The clinical evaluation of the late potentials in patients with ventricular arrhythmias.

We investigated the recognition of late potentials in patients with and without organic heart diseases and spontaneous ventricular arrhythmias. None of the normal subjects had late potentials and patients with ventricular arrhythmias but no organic heart diseases, also had no late potentials as well as patients with idiopathic ventricular tachycardias. Late potentials in patients with idiopathic cardiomyopathy were noted more frequently in the dilated type than in the hypertrophic type, especially in those with high grades of ventricular arrhythmias. Patients with old myocardial infarctions had a higher rate of late potentials recognition in cases of sudden death or ventricular tachycardias. On the other hand, we observed lower rates in patients during early stage of acute myocardial infarction in spite of the evidence of a higher rate of ventricular electrical instability. There was no association between ejection fractions, wall motion scores and late potentials. However, a higher recognition of late potentials was found in patients with inferior or posterior myocardial infarction and ventricular aneurysm. We concluded that the late potential must be evaluated in each of the different groups of organic heart diseases in order to estimate the clinical value of ventricular arrhythmias.

Adolescent↗
PubMed1987

[Effects of meaningful relations between not-to-be-memorized items upon selective memorization].

Forty-five students participated in a selective free recall experiment which was designed to examine the process of selective memorization. The following three conditions were utilized: U (unrelated) list condition, where there was no meaningful relation between any neighboring pair of items; NCR (no-cross-related) list condition, where there were meaningful relations between the neighboring not-to-be-memorized items, but not between the neighboring to-be-memorized and not-to-be-memorized items; CR (cross-related) list condition, where there were meaningful relations between the neighboring to-be-memorized and not-to-be-memorized items. The percentage of correct recall for the to-be-memorized items was smaller and the number of intrusion-errors was larger in the CR list condition than in the U and the NCR list conditions, while there was no difference between the U and the NCR list conditions in those indices. The percentage of correct recall for the not-to-be-memorized items in the NCR and the CR list conditions was larger than in the U list condition in the initial and the middle sections within the serial positions. The results suggested that the not-to-be-memorized items receive semantic analysis and are maintained in short-term memory and that they have the chance to be transformed into long-term memory irrespective of the type of their relations with the to-be-memorized items.

Adult↗
PubMed1987

Possible pathogenesis of congenital stationary night blindness.

We reported a case of congenital stationary night blindness (CSNB) who showed Schubert-Bornschein type electroretinogram (ERG) in the right eye and nearly normal ERG in the left eye with absolute glaucoma. From the electrophysiological findings of both eyes and histological findings of the enucleated eye, we concluded that the mechanism of night blindness in CSNB is an abnormal inhibition in the bipolar cell layer. The experiments in rabbits by vincristine intravenous and intravitreous administrations did not give rise to a negative type ERG, but to a decrease of the amplitude of all ERG components. The lesion of CSNB which was reported to be responsible in the synaptic terminal by Ripps et al could not be confirmed.

Aged↗