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Biomedical subjects

Y Yoshii

Publications and source records attributed to Y Yoshii.

At least 127 records · Page 7Linked to original sources
PubMed1983

[Basic research for visible laser unit for the spinal cord (a preliminary report)].

The cat's spinal dorsal column was irradiated unilaterally with Ar. laser of which power output was 500 mW and the spot size was 2 mm in diameter. The somatosensory evoked potentials (S.E.P.) were recorded bilaterally. In other cats, the fluorescein was injected intravenously for photoactivation and the dorsal column was irradiated with Ar. laser. The conclusion can be summarized as follows: 1) When the small demarcated area was made in the surface of the dorsal column by Ar. laser-irradiation, the early component of S.E.P. was disappeared. The histological finding revealed the destruction of the irradiated dorsal column. 2) The photoactivation effect of Ar. laser was demonstrated in the spinal cord, by using a fluorescein drug. The S.E.P. and the histological finding were the same as those of the nonfluorescein drug group. 3) The S.E.P. was available for the concept of the Laser-Photo-Biological-Effect (L.P.B.E.).

Animals↗
PubMed1982

On the mechanism of heparin-induced potentiation of platelet aggregation.

The role of antithrombin III (AT III) in heparin-induced potentiation of platelet aggregation was investigated using purified AT III and AT III depleted plasma. When ADP or epinephrine was added to citrated platelet rich plasma (PRP) one minute after addition of heparin, marked enhancement of platelet aggregation was observed, compared with the degree of platelet aggregation in the absence of heparin. However, heparin exhibited no potentiating effect on ADP- or epinephrine-induced platelet aggregation when platelets were resuspended in AT III depleted plasma prepared by immunosorption using matrix-bound antibodies to AT III. When purified AT III was added to AT III depleted plasma at a concentration of 20 microgram/ml, potentiation of platelet aggregation by heparin was clearly demonstrated. These results suggest that the effect of heparin on platelet aggregation is also mediated by AT III.

Adenosine Diphosphate↗
PubMed1982

Late vascular effects of whole brain X-irradiation in the mouse.

The whole brains of mice were irradiated with 250 kVp X-rays at 120 rads min-1 (1.6 mm Cu HVL, TSD 50 cm), and a histological study was carried out. The dose range of X-irradiation was from 1,300 to 2,500 rads, i.e., 1,300, 1,500, 1,750, 2,000, and 2,500 rads. Eighty-six mice were used for histological examination. For microscopic examination, the mice were killed at regular postirradiation intervals between 15 and 20, 31 and 40, 41 and 50, 51 and 60, 61 and 70, 71 and 80, 81 and 90, 139 and 177 weeks. The brains were removed immediately thereafter, fixed in Bouin's solution, and embedded in paraffin. A histological examination was performed by a morphometric estimation of vascular lesions, in which the degree of the damage to the arterial system was scored in whole serial brain sections. Necrosis (encephalomalacia), atrophy, cell infiltration, and telangiectatic vascular change of the brain, caused as a result of the fibrinoid necrosis of the large arteries, were observed. Dose-dependent incidence of the fibrinoid necrosis increased between 41 and 87 weeks after irradiation. Mean score of fibrinoid necrosis increased dose dependently approximately 60 weeks after irradiation. It is suggested that scores of large vessel damage do relate to dose at 41 to 87 weeks, and can be used to quantify the vessel injury, and that fibrinoid necrosis of the large vessels may relate to the incidence of radionecrosis.

Animals↗
PubMed1982

[Late vascular effects in irradiated mice brain: in relation to experimental radionecrosis (author's transl)].

The whole brains of mice were irradiated with 250 kVp X-ray at 120 rad min-1 (1.6 mm Cu HVL, TSD 50 cm) and a histological study was done. The dose range of X-irradiation was from 1300 to 2500 rads. i.e., 1300, 1500, 1750, 2000, and 2500 rads. In the microscopic examination, the mice were killed at the regular postirradiation intervals of between 15 and 20, 31 and 40, 41 and 50, 51 and 60, 61 and 70, 71 and 80, 81 and 90, 139 and 177 weeks. A histological examination was performed by a morphometric estimation of vascular lesion in which the degree of the damage to the arterial system was scored through whole serial brain sections. Necrosis (encephalomalacia), atrophy, cell infiltration, and telangiectatic vascular change of the brain, caused as a result of the fibrinoid necrosis of the large artery were observed. Incidence of the fibrinoid necrosis increased dose dependently between 41 and 87 weeks after irradiation. Mean score of fibrinoid necrosis increased dose dependently approximately 60 weeks after irradiation. It is suggested that scores of large vessel damage do relate to dose at 41-87 weeks and can be used to quantify the vessel injury and a fibrinoid necrosis of the large vessels may relate to the incidence of radionecrosis.

Animals↗
PubMed1979

Giant aneurysm of the distal portion of the posterior inferior cerebellar artery.

The authors report a case of a giant aneurysm of the distal portion of the posterior inferior cerebellar artery presenting the classical picture of a tumor of the posterior fossa. CT scan of a giant aneurysm reveals the clear margin and high density area of aneurysm wall, and the homogeneous and high density area of the organized thrombus in a cavity of the aneurysm.

Aged↗
PubMed1979

[A case with giant aneurysm of distal portion of the posterior inferior cerebellar artery (author's transl)].

A case of a giant aneurysm of the distal posterior inferior cerebellar artery has been presented, in which the preoperative sympotoms were those of a space occupying lesion of the posterior fossa. CT scan revealed a round mass in the cerebellum. The wall of this round mass was not enhanced after an intravenous administration of iodine. At operation we found a large saccular aneurysm, about 3 cm in diameter, arising from the distal portion of the left posterior inferior cerebellar artery. By needle decompression and dissection around the aneurysm, we were able to place a Heifetz clip across the neck. After exicision, the aneurysm was found to contain a large thrombus.

Aged↗