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Biomedical subjects

Y Yonehara

Publications and source records attributed to Y Yonehara.

29 records · Page 2Linked to original sources
PubMed1993

Experimental study on growth of epiphysial plate: free graft in rabbits.

The growth potential of a free graft of an epiphysial plate was investigated in rabbits. Two epiphysial plate grafts were harvested from each iliac crest. One was grafted to the head (onto bone) and the other to the ear (onto cartilage). Both of the epiphysial plates enlarged to a maximum height of 1.4 cm and became similar to iliac crests. Enchondral ossification was observed up till approximately 28 weeks of age. We conclude that an epiphysial plate has growth potential after free heterotopic transplantation.

Animals↗
PubMed1993

Mandibular lengthening by gradual distraction: analysis using accurate skull replicas.

Bone lengthening in the upper and lower extremities by gradual distraction has become an accepted procedure. We have used an extraoral device to lengthen the mandible in four patients with unilateral mandibular hypoplasia. Using an accurate skull replica, the proposed corticotomy line, intended direction of lengthening, and appropriate position for the screws were determined. Following distraction, a significant increase in the dimensions of the affected mandible was obtained in each case. In this series, accurate skull replicas proved very useful for defining the anatomy, for surgical simulation and for pre- and postoperative evaluation.

Adolescent↗
PubMed1993

Experimental study of prefabricated flaps using vein grafts.

Prefabrication of a flap may represent a new alternative, not limited by natural vascular territories, for creating donor sites. Experimental procedures in which an A-V shunt results in sufficient flap neovascularization have been reported. This study was undertaken to investigate how neovascularization from the recipient bed affects survival of this type of flap. An 8-cm x 10-cm prefabricated skin flap, nourished by the left epigastric vein, was constructed in a rabbit abdomen. In half the models, a silicone sheet was placed under the flap, to impede neovascularization from the bed. The flaps of both experimental groups showed excellent viability, and no statistically significant difference in survival rate was recognized. This flap was found to be independent of the vascularity of the underlying bed.

Abdomen↗
PubMed1992

[The sensitivity and specificity of various peroxidase stains--the difference between DAB and 3AC stainings].

FAB Cooperative Group has cited 3 or higher percentage in the peroxidase (PO) activity as one of criteria for the diagnosis of acute myeloid leukemia. We have previously reported in two cases of acute myelomonocytic leukemia (M4) that there was a great difference between 3,3'-diaminobenzidine (DAB) and 3-amino 9-ethyl carbazole (3AC) as substrates for PO reaction. In order to confirm the previous result, we extended the cases and compared the PO activities in blood films taken from several leukemic subjects, which were fixed with various kinds of fixatives, using DAB and 3AC as substrates. Their peroxidase activities were also determined through electron microscopy (EM-PO). There were no differences among fixatives and substrates in staining normal granulocytic cells (neutrophils and monocytes) and cells in 13 cases of leukemia, except for two cases, one with M4 and the other with relapse of M2. These showed the highest PO activity with 3AC staining and 10% formaldehyde acetone buffer for fixation. Besides, all types manifested the highest positivity in EM-PO, except for the relapse of M2 that showed a higher positivity in the peroxidase stain by 3AC staining, 10% formaldehyde acetone buffer fixation than the EM-PO. Unlike other leukemic blasts PO reaction products of blast cells of the two cases showed a scattered distribution of microscopic granules. These findings suggested the difference, which was seen in the previous reports, of the PO stain between two substrates might be due not only to sensitivity for staining but to the presence of some heterogeneity such as isoenzyme in the myeloperoxidase.

3,3'-Diaminobenzidine↗
PubMed1991

Binder's syndrome: peculiarities in Japanese patients.

We have seen 4 Japanese patients with Binder's syndrome or maxillonasal dysostosis. The diagnosis of Binder's syndrome was very difficult, based on facial appearances alone. Although the flattened nasal tip was quite unusual in Japanese individuals, the midface retrusion and flattened nasal bridge would be considered within normal limits. Consequently, the diagnosis of Binder's syndrome is only rarely made in Japanese persons. The peculiarities of this syndrome in Japanese patients are discussed and our surgical methods are shown.

Adolescent↗
PubMed1990

Heterotopic gastrointestinal cyst of the oral cavity.

We report a heterotopic gastrointestinal cyst of the oral cavity. Heterotopic islands of gastrointestinal mucosa have been found in the esophagus, the small bowel, and particularly in Meckel's diverticulum. However, their occurrence in the head and neck is extremely rare. Previously reported cases and the theories of embryogenesis are reviewed.

Choristoma↗
PubMed1989

[A case of acute mixed leukemia with expression of J5 and GPIIb/IIIa complex by ABC method].

Identification of the lineage and maturation stage of the leukemic cells is essential for the diagnosis, treatment and followup of acute leukemia. Staining of blood smear by avidin-biotin-peroxidase complex method, which requires no special equipments, enables to observe both morphology and surface antigens at the same time. Simultaneous expression of a B-lymphocyte antigen J5 and a platelet antigen GP IIb/IIIa complex on the same blasts was demonstrated by this technique in the present case.

Acute Disease↗