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排序方式: 共有6007条查询结果,搜索用时 18 毫秒
31.
Y. Uchida M. Kasahara H. Egawa Y. Takada K. Ogawa Y. Ogura K. Uryuhara D. Morioka S. Sakamoto Y. Inomata Y. Kamiyama K. Tanaka 《American journal of transplantation》2006,6(10):2443-2448
Our objective was to analyze problems in the perioperative management and long-term outcome of living donor liver transplantation (LDLT) for biliary atresia (BA). Many reports have described the effectiveness of liver transplantation (LT) for BA, particularly in pediatric cases, but little information is available regarding LT in adults (> or =16 years old). Between June 1990 and December 2004, 464 patients with BA underwent LDLT at Kyoto University Hospital, of whom 47 (10.1%) were older than 16 years. In this study, we compared the outcomes between adult (> or =16 years old) and pediatric (<16 years old) patients. The incidence of post-transplant intestinal perforation, intra-abdominal bleeding necessitating repeat laparotomy and biliary leakage was significantly higher (p < 0.0001, <0.001 and <0.001, respectively) in adults. Overall cumulative 1-, 5- and 10-year survival rates in pediatric patients were significantly higher (p < 0.005) than in adults. Two independent prognostic determinants of survival were identified: a MELD score over 20 and post-transplant complications requiring repeat laparotomy. Outcome of LDLT in adult BA patients was poorer than in pediatric patients. It seems likely that LT will be the radical treatment of choice for BA and that LDLT should be considered proactively at the earliest possible stage. 相似文献
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33.
Y Tsutsumi X Jie K Ihara A Nomura S Kanemitsu H Takada T Hara 《Diabetic medicine》2006,23(10):1145-1150
AIMS: To investigate the contribution of regulatory T cells and co-stimulatory molecules in CD4(+) T cells to the development of Type 1 diabetes (T1D). METHODS: Twelve patients with T1D, nine patients with systemic lupus erythematosus (SLE), and 12 age-matched healthy control subjects participated. We analysed the proportions of CD25(+)CD4(+) T cells and natural killer T cells (NKT cells), and the expression levels of Foxp3, CTLA-4, CD28, ICOS, PD-1 and BTLA in peripheral blood mononuclear cells and purified CD4(+) T cells. RESULTS: There were no significant differences in the proportions of CD25(+) CD4(+) T cells or NKT cells among the three groups. PD-1 expression levels of peripheral CD4(+) T cells from T1D patients were significantly lower than those from healthy control subjects (P = 0.00066). In contrast, PD-1 expression levels were similar in SLE patients and healthy control subjects. The expression levels of Foxp3, CTLA-4, CD28, ICOS and BTLA were similar in the three groups. CONCLUSIONS: Decreased expression of the PD-1 gene in CD4(+) T cells may contribute to the development and/or maintenance of autoimmune T1D. As the population studied was small and heterogeneous, further studies are required to confirm the findings. 相似文献
34.
Koichi Tanaka Kazue Ozawa Satoshi Teramukai Yasutsugu Takada Hiroto Egawa Satoshi Kaihara Yasuhiro Fujimoto Yasuhiro Ogura Mureo Kasahara Masako Ono Hiroshi Sato Kenji Takai Masanori Fukushima Nagahiro Minato 《Liver transplantation》2006,12(5):792-800
The primed status of T cells is markedly different among liver transplant recipients, due to a lifetime of antigen exposure and reduced thymopoiesis by aging, and diseases. This study aims to characterize the preoperative immunological status of CD8+ T cell subpopulations and relate it to the outcome for liver transplant recipients. We classified 112 liver transplant recipients into 5 groups, based on hierarchical clustering of the CD8+CD45 isoform proportion of T cells. In Groups I and II (pediatric), the naive T cell proportion was more than 50%. In adult recipients, Group III was characterized by a naive T cell proportion of 50%, Group IV had the greatest effector/memory T cells (EM), and Group V had the greatest proportion of effector T cells. In Groups IV and V, the effector T cell proportion was considerably higher, and was accompanied by marked downregulation of the CD27+CD28+ subsets and upregulation of interferon gamma (IFN)-gamma, tumor necrosis factor-alpha, and perforin expression. Group V recipients tended to be complicated postoperatively, with a significantly reduced survival rate (1 yr, 66.8%) and markedly reduced Eastern Cooperative Oncology Group performance status. 相似文献
35.
The distribution kinetics of a novel potent immunosuppressant, FK-506 (FK) has been studied in comparison with cyclosporin A (CyA) both in vivo and in vitro using blood specimens. The infusion studies on FK, 5.0 mg kg-1 through the portal and femoral veins showed that the mean hepatic extraction ratio of FK was 27.9 per cent. The effect of clamping both the hepatic artery and the portal vein on the plasma disappearance profiles of FK, 5.0 mg kg-1, and CyA, 3.5 mg kg-1 was studied. The plasma disposition kinetics of CyA was almost the same as in the normal rats. However, the plasma FK levels were about 10 times higher than those obtained in the control group rats. This difference is attributed to the restricted initial distribution of FK to the liver, because the volume of the initial distribution space, V1, of FK was about 10 times smaller than that obtained in normal rats. In in vitro experiments, drug distribution was studied in blood samples (2.0 ml) spiked with FK or CyA, 1.0 micrograms ml-1. The plasma drug levels measured at 2 min after drug administration were 0.842 +/- 0.012 micrograms ml-1 and 0.769 +/- 0.047 micrograms ml-1 for FK and CyA, respectively. The distribution volume in the blood compartment, VB, was determined by dividing the spiked amount of drugs with these plasma concentrations. The VB was 2.38 +/- 0.04 ml for FK and 2.62 +/- 0.16 ml for CyA. There was no significant difference in VB between FK and CyA. The plasma free fraction, fp of the drugs was measured by the equilibrium dialysis method. For FK, the mean fp values (+/- SE) were 1.31 +/- 0.18 per cent (2.0 micrograms ml-1) and 1.93 +/- 0.18 per cent (5.0 micrograms ml-1). For CyA, the fp values were 4.85 +/- 0.36 per cent (1.0 micrograms ml-1) and 5.75 +/- 0.82 per cent (5.0 micrograms ml-1). The hydrophobicity parameter, logP' determined through the HPLC method was 0.386 for FK and 0.545 for CyA. Although FK was less hydrophobic than CyA, its protein binding was higher than CyA. 相似文献
36.
Low doses of the Gn-RH agonist (buserelin, 30 micrograms) were given intranasally to 14 women with clomiphene ineffective hypothalamic amenorrhea three times daily for three weeks in order to study pituitary responses and to induce follicular maturation and ovulation. Clomiphene ineffective hypothalamic amenorrhea patients were classified into two groups by LH-RH stimulation test before the treatment. Group 1 was defined as having basal serum LH and FSH levels lower than 1.5 mIU/ml, LH and FSH peaks lower than 3mIU/ml by LH-RH stimulation test. Group 2 consisted of cases other than those in Group 1. While a significant increase in basal LH and FSH (p less than 0.01, p less than 0.001) and improvement in pituitary response to LH-RH stimulation test were observed in group 1, the basal levels of LH and FSH did not increase significantly and pituitary response to a LH-RH stimulation test was decreased in group 2. It is suggested that pituitary priming occurred in group 1 and pituitary desensitization occurred in group 2. None of 14 patients showed signs of follicular maturation during or after the treatment. The results demonstrated that the biphasic pituitary response to intranasal buserelin spray and the limit of its therapeutic use for the treatment of hypothalamic amenorrhea. 相似文献
37.
Manifestation of EGF receptors and enhancement of an anticancer agent by EGF were studied in cultured cells derived from female genital cancers. 1) The numbers of EGF-receptors of SKG-3a, RMUG-s, HUOA, A-431 and HEC-1 were 1.22 x 10(4), 6.94 x 10(4), 2.75 x 10(4), 5.25 x 10(5) and 0.92 x 10(4) sites per cell respectively. The values for the dissociation constant (Kd) of RMUG-s, SKG-3a, HUOA and HEC-1 were 340pM, 477pM, 989pM and 2,187pM, respectively. 2) All cell lines were stimulated by EGF at low concentrations and inhibited at higher concentrations. The growth stimulation rates for SKG-3a, HEC-1, HUOA and RMUG-s in the presence of 0.01 nM EGF at 48 hours were 8, 18, 21.1 and 3.7%, respectively. The growth inhibition rates for SKG-3a, A-431, HEC-1, HUOA and RMUG-s in the presence of 1.0 nM EGF at 48 hours were 32, 28, 25.8, 11.2 and 6.8%, respectively. 3) The antitumor effect of CDDP was enhanced by the presence of EGF at both a concentration of 0.01 nM (except for A-431) and a concentration of 1.0 nM, in all cell lines. 4) EGF receptors of RMUG-s and HUOA were decreased by CDDP. The values for RMUG-s and HUOA were 1.71 x 10(4), 0.52 x 10(4) (CDDP 0.4 microgram/ml) and 0.95 x 10(4), 0.29 x 10(4) sites per cell (CDDP 2.0 micrograms/ml), respectively. The effect of CDDP on EGF receptors was not recognized in SKG-3a and HEC-1. In brief, EGF receptors were significantly expressed in cell lines derived from female genital cancers.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
38.
Expansion of selection criteria for patients with hepatocellular carcinoma in living donor liver transplantation. 总被引:1,自引:0,他引:1
Takashi Ito Yasutsugu Takada Mikiko Ueda Hironori Haga Yoji Maetani Fumitaka Oike Kohei Ogawa Seisuke Sakamoto Yasuhiro Ogura Hiroto Egawa Koichi Tanaka Shinji Uemoto 《Liver transplantation》2007,13(12):1637-1644
In the present study, the results of living donor liver transplantation (LDLT) for 125 hepatocellular carcinoma (HCC) patients were analyzed to determine optimal criteria exceeding the Milan criteria (MC) but still with predictably good outcomes. On the basis of pretransplant imaging studies, 70 patients met the MC, and 55 patients did not. Patients who exceeded the MC but presented with 相似文献
39.
40.
Hyung-Eun Yoon Kenjiro Fukuhara Toshiya Michiura Minoru Takada Masami Imakita Kentaro Nonaka Kazuhiro Iwase 《The Japanese Journal of Thoracic and Cardiovascular Surgery》2005,53(1):22-28
OBJECTIVES: For the histological diagnosis of small lung cancers of 10 mm or less in diameter (< or =10), resection by video-assisted thoracic surgery (VATS) with computed tomography (CT)-guided marking is feasible. One problem is that a small number of these pulmonary nodules are malignant. We retrospectively analyzed CT images of pulmonary nodules to find better criteria to select candidates for resection among patients with small pulmonary nodules. METHODS: Ninety-four patients with indeterminate peripheral pulmonary nodules underwent wedge resection by VATS. High-resolution CT using a 1.25 mm slice included the area of lesions. Nodules were classified by size (< or =10, 11 to 20, >20 mm) and whether they had a ground-glass opacity (GGO) component. RESULTS: The histology of all 94 nodules showed 52 primary lung cancers, 6 metastatic tumors, 5 benign tumors, 8 intrapulmonary lymph nodes, and 23 inflammatory nodules. Ninety-three percent of nodules larger than 20 mm, 75% of nodules 10 to 20 mm, and 43% of nodules < or =10 mm were malignant. Introducing a classification according to GGO component to nodules, malignancy was detected in 88% of nodules with a GGO component and in 30% of nodules without a GGO component among nodules < or =10 mm. Nodules < or =10 mm with a GGO component showed a statistically significant (p < 0.01) correlation with malignancy. CONCLUSIONS: Pulmonary nodules < or =10 mm with GGO should be considered to have a high possibility of malignancy and to be candidates for resection by VATS. 相似文献