Publications by authors named "Yoshihito Ichikawa"

This work presents a protocol employing the microwave photoconductivity decay (μ-PCD) for measurement of the carrier lifetime in semiconductor materials, especially SiC. In principle, excess carriers in the semiconductor generated via excitation recombine with time and, subsequently, return to the equilibrium state. The time constant of this recombination is known as the carrier lifetime, an important parameter in semiconductor materials and devices that requires a noncontact and nondestructive measurement ideally achieved by the μ-PCD.

View Article and Find Full Text PDF

The molecular background of sporadic endometrial cancer coexisting with colorectal or breast cancer is not clear. We investigated microsatellite instability (MSI) and status of mismatch repair (MMR) gene product, MLH1, MSH2 and MSH6, in 63 sporadic endometrial cancers coexisting with colorectal or breast cancer. Sixteen sporadic endometrial cancers with colorectal cancers (EC), 26 sporadic endometrial cancers with breast cancer (EB) and 21 endometrial cancers without a coexisting cancer (control) were analyzed.

View Article and Find Full Text PDF

A 55-year-old multiparous woman was diagnosed with stage IIIc ovarian clear cell carcinoma. Three years after the first surgery and adjuvant chemotherapy with irinotecan hydrochloride and mitomycin C, she developed common iliac lymph node recurrence. Two cycles of chemotherapy with irinotecan hydrochloride and nedaplatin led to a complete response.

View Article and Find Full Text PDF

Retained placenta accreta can cause catastrophic postpartum hemorrhage. This study aims to determine whether MR imaging can differentiate retained placenta accreta from postpartum hemorrhage caused by other conditions. Fourteen cases suspicious for retained placenta were examined with MR imaging.

View Article and Find Full Text PDF

Thickened or indistinct junctional zone (JZ) is a problematic finding in staging endometrial carcinoma. We studied the incidence, pathological cause of this condition correlated to microcirculation, and the utility of dynamic contrast MRI for differential diagnosis. T2-weighted images were analyzed in 119 cases with endometrial carcinoma.

View Article and Find Full Text PDF

To define the involvement of p16/CDKN2 and p15/MTS2 tumor-suppressor genes for response to chemotherapy in primary epithelial ovarian cancer, we analyzed alterations of the gene in 45 patients who were treated with primary cytoreductive surgery followed by 6 courses of cis-diamminedichloroplatinum (II) (cisplatin)-based combination chemotherapy. Homozygous deletion of p16/CDKN2 and p15/MTS2 genes was found in 8 (18%) and 15 (33%) cases, respectively. Response to the chemotherapy was confirmed by finding at second surgery after the chemotherapy in 26 patients, resulting in 17 responders and 9 nonresponders.

View Article and Find Full Text PDF

Hereditary nonpolyposis colorectal cancer (HNPCC)-related endometrial cancer is associated with mutations in DNA mismatch repair genes. However, chronological changes of these genes in the endometrium have not been studied in women from HNPCC families. Tissue samples of normal endometrium, endometrial hyperplasia without atypia and endometrial cancer were collected at different times from a 41-year-old Japanese woman with a family history of HNPCC.

View Article and Find Full Text PDF