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Biomedical subjects

N Ohyama

Publications and source records attributed to N Ohyama.

29 records · Page 2Linked to original sources
PubMed1991

Membrane fluidity and lipid hapten structure of liposomes affect calcium signals in antigen-specific B cells.

Antigen-specific B-cell clones directed against a 2,4,6-trinitrophenyl (TNP) hapten have been established [Hamano et al. (1990) J. Immunol. 144, 811-815]. We measured here the cytosolic free calcium ion concentration ([CA2+]i) in these B-cell clones after antigen stimulation. Trinitrophenylated liposomes with different length spacers between TNP and phosphatidylethanolamine (TNP-Cn-PE) increased cytosolic free calcium concentration in TNP-specific B cells (clone TP67.21). The magnitude of calcium signals depended on the length of the spacer. TNP-C6-PE in dipalmitoylphosphatidylcholine (DPPC) liposomes triggered larger calcium signals in B cells than TNP-Cn-PE with n = 0, 4, 8, or 12. The magnitude of the calcium signals was strongly dependent on the fluidity of the liposome membranes. TNP-C6-PE in the solid DPPC liposomes triggered the calcium signals in B cells 50-100 times as efficiently as TNP-C6-PE in the fluid dimyristoylphosphatidylcholine liposomes. The difference between the solid liposomes and the fluid liposomes was more pronounced in triggering calcium signals in B cells than in antibody binding to these liposomes.

Animals↗
PubMed1990

[Metastatic penile tumor from lower pharynx: a case report].

Metastatic tumor of the penis is uncommon and only 95 cases have been reported in Japan. A 70-year-old man, who had squamous cell carcinoma of the lower pharynx, complained of urethral induration. Biopsy was performed and pathological diagnosis was metastatic tumor of penis originating from the lower pharynx. Although partial response in tumor size was noted by irradiation therapy, the patient died of multiple metastases in the 4th month after the diagnosis. This case is the first report of metastatic penile tumor originating from the lower pharynx.

Aged↗
PubMed1987

[Acute renal failure after renal trauma in a case of a functional solitary kidney].

Herein we report a case of acute renal failure after renal trauma in a patient with contralateral hypoplastic kidney. The patient was treated conservatively including temporary hemodialysis successfully. In the case of renal trauma, the status and function of the contralateral kidney must be evaluated first, and in the case of a solitary kidney, treatment should be centered on the preservation of its function.

Abdominal Injuries↗
PubMedDate not supplied

Holography of 3D surface reconstructed CT images.

A multiplex hologram (cylindrical holographic stereogram) was successfully made from three-dimensional (3D) surface reconstruction CT images of a child with plagiocephaly. This method appears to be suitable as one of the projectional aids of 3D surface reconstruction CT images that are proving useful in plastic and reconstructive surgery. The principle of the method is described. Also discussed is the possibility of developing a computer-aided hologram synthesizing system that could be used for images obtained with U-arm X-ray equipment (by either cinefilm, or videotape, or digital subtraction angiography) or by CT as well as MR. For practical use, it is necessary for the hologram to be synthesized in a short time. One of the key problems in developing such a machine is the need for an incoherent-to-coherent image converter.

Child↗
PubMedDate not supplied

A proposal of an off-line PACS based on a personal database.

Problems with picture archiving and communication systems (PACS) are focused and an off-line PACS of practical value is proposed in this paper. This system is based on the personal database where each patient has his/her own recording medium. This medium files all medical information as well as images of value, and is carried with a patient through hospital. Advantages over the conventional or on-line PACS communicating through a network are discussed and a possibility of practical use is analysed showing a prototype system. The biggest advantage of this system is quick and easy access to the images of concern and a small amount of cost for initial investment. It is also pointed out that the format of the data recording on the disk has to be standardized so that this system could be used for a medical care system over a wide area.

Computer Systems↗