PubMed Health⌕ Search

Biomedical subjects

Y Yuasa

Publications and source records attributed to Y Yuasa.

240 records · Page 14Linked to original sources
PubMedDate not supplied

Intraperitoneal versus intravenous CPT-11 for peritoneal seeding and liver metastasis.

BACKGROUND: CPT-11 is an effective antitumor agent for gastrointestinal malignancy, but the optimum route of administration is unclear. METHODS: Intraperitoneal administration of this agent was compared with intravenous administration in mouse models for peritoneal seeding and liver metastasis. The peritoneal seeding model and liver metastasis model were respectively established by inoculation of colon 26 tumor cells into the peritoneal cavity and spleen of female BALB/c mise. CPT-11 (40 mg/kg) was injected intraperitoneally or intravenously on days 2 and 5 after inoculation of tumor cells. RESULTS: Intraperitoneal administration of CPT-11 was significantly more effective than intravenous administration for control of both peritoneal seeding and liver metastasis. CONCLUSION: Intraperitoneal administration of CPT-11 may be a more efficient form of adjuvant chemotherapy for prevention of both peritoneal seeding and liver metastasis in patients with gastrointestinal cancer.

Animals↗
PubMedDate not supplied

Trial patterns for selection of major connectors.

A method for selecting the individually suitable form and location of major connectors for partially edentulous patients is described. Light-polymerized resin patterns are alternately placed in the patient's mouth, and the most suitable location and the form of the major connector are selected. This trial pattern method makes it possible to better address the problems posed by difficult removable partial denture patients.

Dental Clasps↗
PubMedDate not supplied

An investigation of preferable taper and thickness ratios for cast circumferential clasp arms using finite element analysis.

This study used a two-dimensional finite element method to investigate the preferred design for a cast circumferential clasp. Finite element models of the clasp arm with the constant flexibility were constructed, the stress was calculated, and the effects of taper and cross-sectional shape on stress were evaluated. The clasp arm with the taper of 0.8 showed less stress than those with other tapers, and the thinner and wider arms showed less stress than those with other cross-sectional dimensions. These results suggest that the use of the preformed clasp-pattern with a taper of 0.8 is preferable for reducing fatigue and/or permanent deformation of the clasp arm.

Chromium Alloys↗
PubMedDate not supplied

Finite element and Weibull analysis to estimate failure risk in resin-bonded retainers.

Three-dimensional finite element analysis and Weibull analysis were used to evaluate the effect of the thickness and the rigidity of the retainers on the risk of failure of an anterior resin-bonded prosthesis. Retainer thickness ranged from 0.4 to 1.4 mm. The physical properties of metals similar to Ni-Cr and type IV gold alloys were used. A concentrated load (100 N) was applied to the incisal edge of the finite element analysis modeled pontic, and the data of other loads (150 to 500 N in 50-N increments) were calculated from the data of 100 N. Subsequent Weibull analysis revealed that failure probability diminished when there was an increase in metal thickness at loads of 300 to 350 N, particularly for the retainer made of a type IV gold alloy. The reduction in failure probability caused by increasing the thickness of the metal was greater when type IV gold alloy was used than when Ni-Cr alloy was used. This investigation suggests that the longevity of resin-bonded retainers can be prolonged by thickening the retainers, rather than using more rigid metals.

Chromium Alloys↗