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41.
42.
Fujita H Iida H Ido K Matsuda Y Oka M Nakamura T 《The Journal of bone and joint surgery. British volume》2000,82(4):614-618
We evaluated the efficacy and biocompatibility of porous apatite-wollastonite glass ceramic (AW-GC) as an intramedullary plug in total hip replacement (THR) for up to two years in 22 adult beagle dogs. Cylindrical porous AW-GC rods (70% porosity, mean pore size 200 microm) were prepared. Four dogs were killed at 1, 3, 6 and 12 months each and six at 24 months after implantation. Radiological evaluation confirmed the efficacy of porous AW-CG as an intramedullary plug. Histological evaluation showed osteoconduction at one month and resorption of the porous AW-GC, which was replaced by newly-formed bone, at 24 months. Our findings indicate that porous AW-GC can be used clinically as an intramedullary plug in THR. 相似文献
43.
J-M Luo H Yoshida S Komura N Ohishi L Pan K Shigeno I Hanamura K Miura S Iida R Ueda T Naoe Y Akao R Ohno K Ohnishi 《Leukemia》2003,17(1):1-8
The SH2 domain-containing inositol 5'-phosphatase (SHIP) is crucial in hematopoietic development. To evaluate the possible tumor suppressor role of the SHIP gene in myeloid leukemogenesis, we examined primary leukemia cells from 30 acute myeloid leukemia (AML) patients, together with eight myeloid leukemia cell lines. A somatic mutation at codon 684, replacing Val with Glu, was detected in one patient, lying within the signature motif 2, which is the phosphatase active site. The results of an in vitro inositol 5'-phosphatase assay revealed that the mutation reduced catalytic activity of SHIP. Leukemia cells with the mutation showed enhanced Akt phosphorylation following IL-3 stimulation. K562 cells transfected with the mutated SHIP-V684E cDNA showed a growth advantage even at lower serum concentrations and resistance to apoptosis induced by serum deprivation and exposure to etoposide. These results suggest a possible role of the mutated SHIP gene in the development of acute leukemia and chemotherapy resistance through the deregulation of the phosphatidylinositol-3,4,5-triphosphate (PI(3,4,5)P3)/Akt signaling pathway. This is the first report of a mutation in the SHIP gene in any given human cancer, and indicates the need for more attention to be paid to this gene with respect to cancer pathogenesis. 相似文献
44.
Ichikawa Y Iida M Ebisui C Fujio C Yazawa K Hanafusa T Kouro T Seki K Nagano S 《Transplantation proceedings》2000,32(7):1982-1983
45.
Changes in levels of serum erythropoietin, serum iron and unsaturated iron binding capacity during chemotherapy for lung cancer 总被引:3,自引:0,他引:3
Sawabe Y; Takiguchi Y; Kikuno K; Iseki T; Ito J; Iida S; Kuriyama T; Yonemitsu H 《Japanese journal of clinical oncology》1998,28(3):182-186
BACKGROUND: The serum erythropoietin level increases markedly during
chemotherapy for leukemia. A number of hypotheses have been built for the
mechanism, none of them satisfactory. Difficulty in evaluating bone marrow
activity hampers the elucidation. Therefore, we focused on patients who had
non-hematological cancer and no evidence of bone marrow suppression.
METHODS: Twelve patients, who had lung cancer (four with small cell cancer
and eight with non-small cell cancer) and who had not undergone any
chemotherapy, were studied. During chemotherapy, we measured serum
erythropoietin, serum iron, unsaturated iron binding capacity and
hemoglobin concentration in these patients. RESULTS: The serum
erythropoietin level before chemotherapy (10.8 +/- 7.4 mU/ml) was within
the normal range but the peak values after the first treatment (73.4 +/-
90.4 mU/ml) increased in all patients. In the patients with small cell
cancer, a transient but marked increase in erythropoietin value (204.6 +/-
167.3 mU/ml) was observed after each session of chemotherapy while
hemoglobin concentration decreased gradually. Throughout treatments,
elevation of the serum iron concentration and concomitant reduction of
unsaturated iron binding capacity were observed after each session of
chemotherapy. They regained their original values whilst the serum
erythropoietin level decreased after each chemotherapy session was
completed. CONCLUSIONS: It is suggested that the suppression of erythroid
marrow by chemotherapeutic agents causes the changes in serum
erythropoietin level during chemotherapy in patients with lung cancer.
相似文献
46.
Correlation between bone marrow edema and collapse of the femoral head in steroid-induced osteonecrosis 总被引:26,自引:0,他引:26
Iida S Harada Y Shimizu K Sakamoto M Ikenoue S Akita T Kitahara H Moriya H 《AJR. American journal of roentgenology》2000,174(3):735-743
OBJECTIVE: The purpose of this study was to clarify whether bone marrow edema is detectable on initial MR imaging of steroid-induced osteonecrosis of the femoral head. SUBJECTS AND METHODS: Forty-eight hips with osteonecrosis were examined consecutively with MR imaging and radiography. In a previously reported screening program, osteonecrosis was diagnosed on MR imaging when subchondral bands of abnormal signals were present. In the screening program, the MR images of 200 hips of 100 patients receiving high-dose steroid therapy were examined prospectively. Subchondral bands were detected in 48 hips at a mean of 14 weeks after the initiation of steroid therapy. RESULTS: On follow-up MR imaging of 47 hips (one hip excluded) bone marrow edema was initially observed in 13 hips after the onset of hip pain. MR imaging of the remaining 34 hips did not reveal bone marrow edema and the patients were all asymptomatic. MR imaging of 31 of the 34 hips continued to show subchondral bands and MR imaging of the other three hips indicated that the subchondral bands had disappeared. When bone marrow edema was detectable, abnormal findings on radiography were slight but 11 (85%) of the 13 hips progressed to advanced osteonecrosis. Bone marrow edema was highly correlated with the subsequent collapse of the femoral head (p<0.0001). CONCLUSION: Bone marrow edema was not present on initial MR imaging of osteonecrosis. Bone marrow edema should be considered a marker for potential progression to advanced osteonecrosis, and careful examinations for osteonecrosis are necessary when bone marrow edema is seen. 相似文献
47.
Leiomyosarcoma of the scrotum is a rare tumor. Up to 1999, only 29 cases have been reported in the literature worldwide. A 27-year-old man presented with a mass on the left side of the scrotum which had been painless and had gradually enlarged over the previous 10 years. During the following 3 months, however, it became painful and he was then referred to our hospital. Physical examination revealed a solid mass on the left side of the scrotum, measuring 7 cm in diameter, which was not adhering to the testis or to the vas deferens. The tumor was surgically resected. The histological examination confirmed the diagnosis of well differentiated leiomyosarcoma. Adjuvant therapy was considered unnecessary. The follow-up at 41 months revealed no local recurrence or distant metastasis. 相似文献
48.
Accelerated growth signals and low tumor-infiltrating lymphocyte levels predict poor outcome in T4 esophageal squamous cell carcinoma 总被引:10,自引:0,他引:10
Yasunaga M Tabira Y Nakano K Iida S Ichimaru N Nagamoto N Sakaguchi T 《The Annals of thoracic surgery》2000,70(5):1634-1640
BACKGROUND: Little is known about the biological nature of T4 esophageal carcinoma growth signals and host defenses. METHODS: Paraffin-embedded sections from 78 patients with T2 to T4 esophageal squamous cell carcinoma who underwent operation were analyzed with immunohistochemistry. RESULTS: Positive cyclin A showed a significantly greater increase in T4 tumors than in those of other stages, and negative p27 showed a significantly greater decrease in T4 tumors than in large T3 stage tumors (tumor size > or = 4.0 cm). Patients with low-grade tumor-infiltrating lymphocyte (TIL) density showed a significantly greater decrease in T4 than in T2. The combination of p27 and cyclin A was a significant independent prognostic factor among T and N factors in multivariate analysis. TIL density was an independent prognostic factor among immunonutritional variables such as serum albumin concentration and the number of total blood lymphocytes. CONCLUSIONS: T4 esophageal squamous cell carcinoma has a poor prognosis, which is associated with increased p27-negative and cyclin A-positive growth signals in the tumor and with low TIL density in the host. 相似文献
49.
Ohno Ken; Araki Naohiro; Yanase Toshihiko; Nawata Hajime; Iida Mitsuru 《Toxicological sciences》2005,83(2):406
The following sentences should have read: Results, Reproducibility 相似文献
50.
Iida T Yasuda M Miyazawa M Fujita M Osamura RY Hirasawa T Muramatsu T Murakami M Saito K Mikami M 《Archives of gynecology and obstetrics》2008,277(6):539-546
Material and methods We analyzed the expression of hypoxia inducible factor-1α (HIF-1α) and glucose transporter-1 (GLUT-1) by immunohistochemistry
in ovarian serous and mucinous tumors from the point view of the histological characteristics and acquisition of malignancy.
A total of 102 ovarian tumors were examined, composed of 31 adenomas (serous 17 and mucinous 14), 32 borderline tumors (serous
13 and mucinous 19), and 39 adenocarcinomas (serous 21 and mucinous 18).
Results The overall positive ratios were as follows: HIF-1α, 74% of
adenomas, 91% of borderline tumors, and 100% of adenocarcinomas; and GLUT-1, 68% of adenomas, 95% of borderline tumors, and
100% of adenocarcinomas. Comparing serous tumors and mucinous tumors, there was no significant difference in the positive
ratios of HIF-1α and GLUT-1 of adenomas, borderline tumors, and adenocarcinomas. However, both markers were more strongly
expressed in serous adenocarcinomas (HIF-1α, 3 + 100%; GLUT-1, 3 + 76%) than in mucinous adenocarcinomas (HIF-1α, 3 + 61%;
GLUT-1, 3 + 28%). The results of immunoblotting and mRNA expression level analyses corresponded with those of immunohistochemical
expression profiles. DNA binding assay also demonstrated that HIF-1 is more commonly activated in serous adenocarcinomas than
in mucinous adenocarcinomas.
Conclusion HIF-1α and GLUT-1 expressions seemed to be coordinated to adapt ovarian tumor cells into hypoxic conditions in close association
with the acquisition of malignancy. We consider that the relatively strong expression of both markers in serous tumors compared
with mucinous tumors is related to the difference in their histological characteristics. 相似文献