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Biomedical subjects

A Tamai

Publications and source records attributed to A Tamai.

At least 37 records · Page 2Linked to original sources
PubMed1992

[Effect of GABA antagonists on the rat electroretinogram].

It has been shown that gamma-aminobutyric acid (GABA) is densely packed in the inner nuclear and plexiform layers in the rat retina, where it is mainly located within a subgroup of amacrine cells. This study examined the effects on the electroretinogram of GABA antagonists infused into the vitreous cavity of urethan-anesthetized rats. Infusions of the GABAA antagonist, bicuculline (0.1-10 mM, 3 microliters) significantly enhanced the b-wave amplitude and reduced the oscillatory potentials (OPs). Similar effects were also produced by infusions of the GABAB antagonist, phaclofen (10 mM, 3 microliters), although lower doses (0.1-1 mM, 3 microliters) had no effect. These results suggest that the actions of GABA, presumably released from amacrine cells, on both GABAA and GABAB receptors are involved in the normal generation of the b-wave and OPs.

Animals↗
PubMed1991

Nomogram for penile biothesiometry.

Three hundred and fifty men, aged between 17 and 80 years, with normal sexual anamnesis and without any neurological pathology, underwent finger (index) and penile biothesiometry using a biothesiometer. Tabular and graphical nomograms were obtained according to age and instrumental values. The use of the above-mentioned nomograms is an effective aid in detecting each individual case.

Adolescent↗
PubMed1990

[Cost-benefit relationship between endoscopic resection (TURP) and open surgery (Millen) in prostatic hypertrophy ].

Evaluation of the cost/benefit relationship between TURP (50 cases) and Millin (30 cases). The factors considered are as follows: average post-operative hospitalization, average catheterisation time, average operation time, cost of materials, number of operators employed, number of transfused blood units. The post-operative hospitalization relating to the two kinds of operation varies considerably with a difference of 5.15 days less for the TURP, while the average catheterisation time doesn't seem to be affected. Blood transfusion was necessary in the 43.3% (0.75 unit/patient) of cases for the Millin compared to the 14% (0.26 unit/patient) for the TURP. Evaluation of economical advantages between TURP and Millin shows a relationship of 1:2.3 in favour for of TURP.

Aged↗
PubMed1989

Influence of microinjection of glucagon into the amygdala on hepatic acetate metabolism in rabbits.

Glucagon was injected directly into the medial amygdala (AMYG) of rabbits, and changes in hepatic acetate metabolism were studied. The injection of 3 ng glucagon into the AMYG of intact rabbits increased the rates of 14C transfer from 14C-1-acetate into CO2, glucose, ketone bodies, cholesterol ester, free fatty acids and phospholipids but decreased those of 14C transfer into triglyceride. However, the glucagon injection into the AMYG of rabbits with lesions of stria terminals or into the parietal cortex of intact rabbits had no effects on the hepatic acetate metabolism. These observations support the hypothesis that the AMYG is a part of the glucagon-sensitive brain regulator system in the hepatic acetate metabolism.

Acetates↗
PubMed1989

Electron microscopic observation of the cells floating in the anterior chamber in a case of phacolytic glaucoma.

The floating cells in the anterior chamber and a trabeculectomy specimen obtained from a 63-year-old man with phacolytic glaucoma were observed under a light microscope and a transmission electron microscope. Numerous macrophages which had phagocytized degenerated lens material (phacolytic cells) were observed in the anterior chamber, and free-floating degenerated lens material was also conspicuous. Melanin-laden macrophages accompanied by a small number of erythrocytes, ghost erythrocytes, lymphocytes, and macrophages showing erythrophagocytosis and leukophagocytosis and phagocytizing degenerating macrophages were also observed in the anterior chamber. In the trabeculectomy specimen, the intertrabecular space was obstructed by the phacolytic cells, melanin-laden macrophages, cell debris and free-floating degenerated lens material. It is concluded that these substances may cause obstruction of the aqueous humor outflow pathways, resulting in glaucoma.

Anterior Chamber↗
PubMed1988

Influence of microinjection of corticosterone into hippocampus on hepatic acetate metabolism in rabbits.

Corticosterone was injected directly into the hippocampus of rabbits, and changes in hepatic acetate metabolism were studied. The microinjection of corticosterone with seasame oil into hippocampus decreased the rates of 14C transfer from 14C-1-acetate into CO2 and free cholesterol, and increased 14C transfer into glucose, ketone bodies, triglyceride, free fatty acids and phospholipids. But after microinjection of corticosterone into the hippocampus of rabbits with lesions of dorsal fornix, hepatic acetate metabolism did not differ from that of control rabbits, which received injection of seasame oil into the same brain region. From these results it might be suggested that the hippocampus is a part of corticosterone-sensitive brain regulator system in the hepatic acetate metabolism.

Acetates↗
PubMed1987

[Epididymitis in adults. Retrospective study of 110 cases].

A review was conducted of 110 cases of epididymitis, most of these patients (71.9%), especially those under 50 years of age, having negative urine cultures: this appears to confirm the high frequency of Chlamydia T infection in the age group 20 to 50 years when sexual activity is at its maximum. Urinary output was normal in 60 of 79 patients and urography exploration provided normal results in 69 of the 110 patients (63%), particularly in those under 50. It is concluded, therefore, that urography is not necessary in patients under 50 but remains necessary in those in older age groups.

Acute Disease↗
PubMed1986

Spectrally selective flash early receptor potential (ERP) in dichromats.

The human spectrally selective flash early receptor potential (ERP) was studied in 12 dichromats: 6 protanopes (12 eyes) and 6 deuteranopes (12 eyes). Color filters used were Kodak Wratten filters No.23A, No.57, and No.47 for the red, green, and blue flash ERPs, respectively. The ERP amplitude was measured between the summits of R1 and R2. Mean amplitudes of the red flash ERP and green flash ERP were highly significantly decreased in the protanopes (p less than 0.001) and deuteranopes (p less than 0.01) as compared with the corresponding data in 10 normal subjects (20 eyes). The mean amplitude of the blue flash ERP was significantly lower than normal (p less than 0.001) in the deuteranopes. The mean ratio of the blue flash ERP amplitude to the red flash ERP amplitude showed a highly significant increase in the protanopes (p less than 0.001) and a highly significant decrease in the deutoranopes (p less than 0.001) compared with the mean ratio in the normal subjects, indicating a new, useful index for the objective clinical detection of congenital color defects.

Adolescent↗
PubMed1986

Influence of lesions of the limbic-hypothalamic system on metabolic response of pyruvate to daily repeated immobilization stress in rabbits.

The pyruvate metabolic response to the 1st exposure (exposure on the 1st day) to immobilization stress (IMO) were considerably altered by lesions of the periventricular arcuate nucleus (ARC), ventromedial hypothalamus (VMH), stria terminalis (ST) and dorsal fornix (FX). The pyruvate metabolic responses to IMO were completely abolished by seven times repetition of exposure to IMO in the rabbits with lesions of ARC and VMH; they were similar to sham-operated groups. In rabbits with lesions of ST and FX, the pyruvate metabolic responses to the 7th exposure (exposure on the 7th day) to IMO were almost the same as those after the 1st exposure to IMO, but these metabolic responses were completely abolished by the seven times repetition of exposure to IMO in the sham-operated animals. These results suggest that firstly the ARC, VMH, amygdala (AMYG)-ST system and dorsal hippocampus (HPC)-FX system are involved in the pyruvate metabolic responses to the 1st exposure to IMO, and secondly, that the AMYG-ST system and the HPC-FX system are involved in the disappearance process of pyruvate metabolic responses to IMO by the daily repetition of exposure to IMO.

Animals↗
PubMed1983

Light and electron microscopic studies of malignant melanoma of conjunctiva and palpebra.

The authors experienced one case of malignant melanoma of the superior palpebral conjunctiva and the inferior palpebral skin, originating from benign acquired melanosis of the bulbar conjunctiva which developed in a 48-year-old man. Orbital exenteration including superior and inferior palpebrae was performed, and the removed tissue was examined by light and electron microscopy. In the temporal bulbar conjunctiva, melanocytes containing abundant fine melanin granules proliferated over almost the whole area of the epithelial layer. Cellular atypia and karyomitosis were not observed. The basement membrane remained intact with no proliferation of melanocytes in the substantia propria. However, in the perivascular area, in addition to the moderately prominent infiltration by lymphocytes and plasma cells, infiltration by melanophages was observed relatively frequently. Based on these findings, it was confirmed that the primary lesion of the bulbar conjunctiva was an acquired melanosis of Stage IB as classified by Zimmerman. The black nodular tumors of the superior palpebral conjunctiva and inferior palpebral skin consisted of melanoma cells showing markedly prominent cellular and nuclear atypia. The nuclei showed indentations in the membrane with electron-lucent karyoplasm, each having one nucleolus. The cytoplasm contained many round or elongated melanosomes in various developmental stages, with sizes of about 0.7 micron. Scattered among melanoma cells were a number of melanophages which had phagocytized many melanosomes at various stages of maturity.(ABSTRACT TRUNCATED AT 250 WORDS)

Conjunctival Neoplasms↗