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Biomedical subjects

Y Higashi

Publications and source records attributed to Y Higashi.

At least 253 records · Page 14Linked to original sources
PubMed1990

[The problems in the ultrasonography and its countermeasure].

The problems in the ultrasonographic examination are discussed in four categories as follows; 1) Problems arising from the characteristics of the ultrasonographic equipment such as limited field of view, poor resolution in the far field, dead space in examination of the liver, etc. 2) Problems related to the operation of the equipment such as optimizing the gain, STC, dynamic range, and selection of the focal depth and dynamic focus technique. 3) Problem concerning the interpretation of the ultrasonic images such as determining the orientation of the organ displayed on the image, intra-observer divergence in interpretation of the ultrasonogram. 4) Financial problems about ultrasonography.

Humans↗
PubMed1990

[A case of osteosarcoma following radiation therapy].

A case is presented in whom a new malignant neoplasm developed in fields of prior irradiation. The tumor was histologically diagnosed as osteosarcoma. This case satisfied the criteria of the radiation induced sarcoma proposed by Maehara et al.

Bone Neoplasms↗
PubMed1990

[Harlequin syndrome (unilateral flushing and sweating attack) due to a spinal invasion of the left apical lung cancer].

A 54-year-old man was admitted to our hospital because of a persistent pain of the left cervix and scapular region of three-month duration and an abnormal shadow in the chest roentgenograms. Neurological examinations, chest roentgenograms, chest CT scanning, vertebral tomograms and myelogram revealed Pancoast's syndrome concomitant with Horner's syndrome. Four months later, the patient complained of a sudden onset of unilateral flushing and sweating appearing on the right face, cervix and upper chest. Eye drop tests with cocaine, epinephrine and tyramine indicated the lesion of ciliospinal centers between the 8th cervical and 2nd thoracic spines. The unilateral flushing and sweating attack appearing on the intact side without Horner's syndrome seemed to be an excessive response by an intact sympathetic pathway, the other side failing to respond because of a sympathetic deficit.

Flushing↗
PubMed1989

[CT findings of malignant lymphoma of the anterior mediastinum--differentiation from invasive thymoma].

CT findings were compared retrospectively between 9 cases with malignant lymphoma of the anterior mediastinum and 8 cases with invasive thymoma. CT findings of malignant lymphoma were as follows: 1) The majority of the tumors were bilateral and extended beyond the anterior mediastinum to the other mediastinum compartments. 2) Their margin was either smooth or lobulated. 3) Their density was either homogeneous or heterogeneous. In the case with heterogeneous density, ring, triangle and/or band-like low density areas, just like interspace of fused lymph nodes, were demonstrated. Calcification or cysts could not be shown. 4) Patent inherent vessels without deviation were occasionally demonstrated running through the tumors. 5) The tumors faced and contacted widely to anterior chest wall and often pressed the lung laterally at the anterior parietomediastinal pleural reflection. 6) Pleural implants were not demonstrated.

Adolescent↗
PubMed1989

Calcium ion sequestration by N-acylamino acids within the rectal membrane and the enhancement of the rectal absorption of sodium ampicillin in rats.

The present study reports the contribution of the calcium ion sequestration capacity of N-acylamino acids, used as absorption promoters, to their absorption-promoting action. Different extents of enhanced rectal absorption of sodium ampicillin by N-acylamino acids were well explained by the predicted amount of calcium ion sequestrated by N-acylamino acids existing in the rectal membranes. The amount of N-acylamino acids that penetrated into the rectal membrane was predicted by the product of the Rm value and the dose of N-acylamino acids. Thus, in the present study, it was demonstrated that the extent of the promoting effect of adjuvants at various doses on the membrane permeability may be predicted by multiplying the calcium ion sequestration capacity obtained in vitro by the lipophilicity and the dose applied to the rectal lumen of adjuvants.

Amino Acids↗
PubMed1989

Squamous cell carcinoma with cyst of the thyroid.

Two cases of primary squamous cell carcinoma associated with a thyroid cyst in the thyroid are described. The majority of squamous cell carcinomas reported so far have had some degree of co-existing adenocarcinoma, while the cases presented in this report had no glandular component at all. The histogenesis of squamous cell carcinoma is not clear, but at present, it is believed that most cases arise from the follicular epithelium. In our cases, in spite of an intensive examination of serially sectioned specimens, no areas of adenocarcinoma, squamous metaplasia from the follicular epithelium, or congenital squamous remnants could be found.

Aged↗
PubMed1989

Increased accumulation of N-isopropyl-p-(123I)-iodoamphetamine in two cases with mitochondrial encephalomyopathy with lactic acidosis and strokelike episodes (MELAS).

We present two cases with mitochondrial encephalopathy with lactic acidosis and strokelike episodes (MELAS), which showed both increased and decreased accumulation of N-isopropyl-p-(123I)-iodoamphetamine (123I-IMP) in single photon emission computed tomography (SPECT). The increased accumulation of the tracer occurred, before low density appeared on conventional computed tomography, suggesting that 123I-IMP SPECT may be useful in pathophysiological study of MELAS.

Acidosis, Lactic↗
PubMed1989

Relationship of changing delta 4-steroid 5 alpha-reductase activity to [125I]iododeoxyuridine uptake during regeneration of involuted rat prostates.

To elucidate the phenotypic expression of proliferating prostatic cells, rats were castrated, and the regenerating process of involuted ventral prostates during testosterone propionate (TP) administration was investigated by examining morphology, [5-125I]iododeoxyuridine (125I-UdR) uptake, DNA content, weight, acid phosphatase, and delta 4-steroid 5 alpha-reductase (5 alpha-reductase) activities. Morphologically, TP treatment initially increased the number of epithelial cells lining glandular lobules and subsequently restored the shape of epithelial cells. 125I-UdR uptake peaked on Day 3 of TP treatment and stayed at higher levels than for uncastrated controls until Day 14 of treatment. Prostatic weight, protein content, acid phosphatase, and DNA content returned to uncastrated control levels by Day 14 of TP treatment. TP administration markedly stimulated prostatic 5 alpha-reductase activity, which peaked on the Day 5 of treatment and decreased to uncastrated control levels by Day 14 of treatment. It is concluded that TP administration to castrated rats initially induced active mitotic division of the remaining stem cells, followed by formation of differentiated functional epithelial cells. Prostatic 5 alpha-reductase was highly active at the initial phase of active mitotic cell division. The major portion of the increased enzyme activity can be regarded as a phenotypic expression of stem or transient cells of prostatic epithelium.

3-Oxo-5-alpha-Steroid 4-Dehydrogenase↗
PubMed1989

Abdominal aortic aneurysm of unknown origin and renovascular hypertension in a 25 year old male.

A 25 year old male had an abdominal aortic aneurysm involving bilateral renal arteries. Aortography revealed no irregularity in the aortic wall but a slight kinking at the tenth thoracic level followed by a fusiform aneurysm. Computed tomography (CT) showed an enlarged aortic lumen with an intraluminal thrombus. Plasma renin activity (PRA) was markedly increased (11 ng/ml/h), and the administration of captopril caused a further increase in PRA with a significant reduction in blood pressure, indicating the presence of renovascular hypertension. Abdominal aneurysm in a young adult is very rare. The etiology of the aneurysm appears to be idiopathic.

Adult↗
PubMed1989

[A study of intercellular communication of human transitional cell carcinoma cell lines].

Intercellular communication (IC) was investigated by a dye transfer method in 5 human bladder carcinoma cell lines, JTC-29, JTC-30, JTC-32, HUB-41 and T-24 which showed various histological anaplasia when transplanted into nude mice. IC was investigated as follows; 1) IC among cells of each bladder carcinoma cell lines, 2) IC between various combination of different cell lines and 3) IC between cells of bladder carcinoma cell lines and fibroblasts prepared from the human skin or prostate. High IC was observed among JTC-30 cells which showed a differentiated pattern when transplanted into nude mice. JTC-32 and HUB-41, of which transplanted tumors showed poorly differentiated patterns, demonstrated lower IC than JTC-30. Statistical significance was present only between JTC-30 and JTC-32 cells (p less than 0.05). T-24 which formed histologically anaplastic tumor in nude mice demonstrated markedly poor IC. Second, IC between two different cell lines was demonstrated only between JTC-30 and JTC-32. Third, fibroblast from the skin and prostate had high IC but showed apparent IC with none of bladder carcinoma cell lines. These findings indicate that ICs of bladder tumor cells vary with cell lines tested and appear to decrease with progress of malignant anaplasia. Furthermore, the fact that there is sometimes high IC and sometimes lack of IC between differentiated and undifferentiated tumor cells suggests a possible role of IC in prevention of malignant progression. The present study provides no evidence of IC between bladder tumor cells and fibroblasts, which in some reports have been suggested to be an important phenomenon in evaluating the metastatic capacity of cancer cells.

Animals↗