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排序方式: 共有4824条查询结果,搜索用时 15 毫秒
71.
Ohwada S Sato Y Sato N Toyama Y Okano T Nakasone Y Ogawa T Morishita Y 《European surgical research. Europ?ische chirurgische Forschung. Recherches chirurgicales européennes》2000,32(6):353-358
BACKGROUND: This study was done to investigate the effects of blood transfusion on gastrointestinal anastomotic wound healing and leukocyte function. METHODS: Closed-colony male Wistar rats were divided into five groups in a group-mixed fashion and underwent laparotomy (the CONT and WB groups) or gastrectomy and gastroduodenostomy (the GAST, GAST/WB and GAST/LDRWB groups). Immediately, they received 3 ml of saline (the CONT and GAST groups) or blood from Wistar donors (the WB and GAST/WB groups, whole blood; the GAST/LDRWB group, a transfusion of irradiated and leukocyte-depleted whole blood). The animals were killed 7 days after surgery. RESULTS: The GAST/WB group had a higher incidence of anastomotic abscess, a lower level of factor XIII and a lower maximum breaking strength than the GAST group. Gastrectomy decreased L-DCL (luminol-dependent chemiluminescence) more than whole-blood transfusion. In the GAST/WB group, L-DCL was severely reduced, while in the GAST/LDRWB group it was roughly equivalent to the level in the GAST group. CONCLUSIONS: Whole-blood transfusion increased the incidence of anastomotic abscess and impaired anastomotic wound healing, and these might relate to the reduction of L-DCL. Irradiated and leukocyte-depleted transfusion can improve these effects. 相似文献
72.
Hisahara S Takano R Shoji S Okano H Miura M 《Journal of neural transmission. Supplementum》2000,(58):135-142
Oligodendrocytes are myelin forming cells in mammalian central nervous system. About 50% of oligodendrocytes (OLGs) undergo cell death in normal development. In addition, OLG cell deaths have been observed in demyelinating diseases including multiple sclerosis (MS). Clinical observations and in vitro cell culture studies have suggested that cytokines mediate OLG cell damage in multiple sclerosis (MS). Among the cytokines, tumor necrosis factor (TNF) is thought to be one of the mediators responsible for the damage of OLGs in MS. The administration of TNF-alpha to primary cultures of OLGs induced DNA fragmentation, and significantly decreased the number of live OLGs. Chemical inhibitors Ac-YVAD-CHO (a specific inhibitor of caspase-1 (ICE)-like proteases) enhanced the survival of TNF-alpha treated OLGs better than Ac-DEVD-CHO (a specific inhibitor of caspase-3 (CPP32)-like proteases). These results indicate that caspase-1-mediated cell-death pathway are activated in TNF-induced OLG cell death. Caspase-11 is involved in activation of caspase-1. Oligodendrocytes from caspase-11-deficient mice are partially resistant to TNF-induced OLG cell death. Our results suggest that the inhibition of caspase-1 sufamily may be a novel therapeutic approach to treat MS. 相似文献
73.
Shin Kariya Mitsuhiro Okano Hisashi Hattori Yuji Sugata Rie Matsumoto Kunihiro Fukushima Patricia A Schachern Sebahattin Cureoglu Michael M Paparella Kazunori Nishizaki 《Otology & neurotology》2006,27(8):1089-1093
OBJECTIVE: Otitis media with effusion is one of the most common and intractable ear diseases. However, the role of Th1, Th2, and immunoregulatory cytokines on the pathogenesis of the disease in adult patients remains to be determined. The aim of this study is to disclose the cytokine expression in middle ear effusions (MEEs) in adults and to compare the profile on the basis of the presence of allergic rhinitis and the type of effusions. STUDY DESIGN: A prospective controlled clinical study. PATIENTS: MEEs were collected from 80 adult subjects. The concentration of interleukin (IL)-2, IL-4, IL-5, IL-10, IL-12, and interferon (IFN)-gamma in MEEs were determined by using enzyme-linked immunosorbent assay. RESULTS: IL-2, IL-4, IL-5, IL-10, IL-12, and IFN-gamma in MEEs were detected in 60 (75.0%), 33 (41.3%), 42 (52.5%), 14 (17.5%), 80 (100%), and 66 (82.5%) samples, respectively. Among these cytokines, only the concentration of IL-4 in the allergic rhinitis-positive group was significantly higher than that in the allergic rhinitis-negative group. On the other hand, IL-2, IL-12, and IFN-gamma were detected, regardless of the presence of allergic rhinitis, and the concentration of these cytokines correlated with each other. The correlation between the concentration of IL-4 and IL-5 was also detected. In addition, both the incidence rate and the concentration of IL-10 in MEEs were significantly higher in the mucoid type compared with those in the serous type effusions. CONCLUSION: Regardless of allergic status, IL-12 may play a critical role in the pathogenesis of otitis media with effusion by affecting the production of IL-2 and IFN-gamma. In addition, IL-4 may have some impact on the immunologic condition in adults with allergic rhinitis. IL-10 potentially affects the viscosity of MEEs. 相似文献
74.
Effect of promoter methylation of the p16 gene on phosphorylation of retinoblastoma gene product and growth of hepatocellular carcinoma cells. 总被引:2,自引:0,他引:2
The biological significance of hypermethylation of p16 gene promoter in human hepatocellular carcinoma (HCC) cells remains to resolved. In order to clarify the significance of methylation of p16 gene promoter, we examined the methylation status of p16 gene in association with phosphorylation of retinoblastoma gene product (pRb) and cell growth in human HCC cell lines. The presence of methylation was examined by methylation-specific PCR. Expression and phosphorylation of p16 and pRb were examined by Western blot analysis. Genetic changes were analyzed by multiplex PCR and DNA sequencing. The effect of demethylation of p16 was assessed by cell growth. p16 gene promoter was methylated in HuH7 and HLF cells. The demethylating agent, 5-aza-2-deoxycytidine (5-Aza-CdR), upregulated p16 mRNA in HuH6 and HuH7 cells. 5-Aza-CdR increased p16 protein expression in HuH6, HuH7, and HLF cells, and it clearly decreased the phosphorylation level of pRb in HuH6, HuH7 and PLC/PRF/5 cells. Treatment with 5-Aza-CdR inhibited the growth of HuH7 cells. Homozygous deletion and significant mutations were absent. Methylation in the p16 promoter region is biologically significant, being associated with phosphorylation of pRb and cell growth in human HCC cells. 相似文献
75.
T Ueha-Ishibashi T Tatsuishi K Iwase H Nakao C Umebayashi Y Nishizaki Y Nishimura Y Oyama S Hirama Y Okano 《Toxicology in vitro》2004,18(5):563-569
There is a concern on the part of public health community that adverse health consequences by thimerosal, a preservative in vaccines for infants, may occur among infants during immunization schedule. Therefore, the effect of thimerosal on cellular content of glutathione was examined on thymocytes obtained from 4-week-old rats using a flow cytometer and 5-chloromethylfluorescein diacetate. Thimerosal at concentrations ranging from 1 to 10 microM reduced the cellular content of glutathione in a concentration-dependent manner, and the complete depletion of cellular glutathione was observed when the cells were treated with 30 microM thimerosal. L-Cysteine significantly attenuated the actions of thimerosal to reduce the glutathione content and to increase the intracellular Ca2+ concentration. Prolonged incubation (24 h) with 1-3 microM thimerosal induced the apoptosis. The cytotoxic action of thimerosal was greatly augmented when the cells suffered oxidative stress induced by H2O2. It may be unlikely that thimerosal exerts potent cytotoxic action under the in vivo condition because the blood concentration of thimerosal after receiving vaccines does not seem to reach micromolar range and nonprotein thiols at micromolar concentrations are present in the blood. 相似文献
76.
77.
Toshimitsu Tohya M.D. Teruo Iwamasa M.D. Masao Maeyama M.D. 《Gynecologic oncology》1986,23(3):291-303
The carcinoembryonic antigen (CEA) in the cyst fluid of ovarian mucinous and serous tumors was investigated. The molecular weight and antigenicity of the CEA from both ovarian tumors were very similar to those of colon cancer CEA as determined by SDS electrophoresis and double immunodiffusion on agar plates. In the cyst fluid of ovarian mucinous tumors, the amount of CEA was generally high and CEA of molecular weight (MW) 200,000 was increased. In contrast, in the cyst fluid of ovarian serous tumors, the CEA amount was low and CEA variants of MW 370,000 and 180,000 were present in addition to the main CEA of MW 200,000. Immunohistochemically, CEA was stained mainly in the intestinal type epithelium of ovarian mucinous tumors, and the CEA revealed a tendency to be stained more frequently and strongly with increasing degree of tumor malignancy. Thus, ovarian mucinous tumors (especially the intestinal type epithelium) produced large amounts of CEA which closely resembled colon cancer CEA, whereas ovarian serous tumors produced small amounts of CEA, including some CEA variants. In the study of ovarian epithelial tumors, CEA may be useful as a marker for the malignant transformation of ovarian mucinous tumors. 相似文献
78.
79.
Hepatoma-derived growth factor (HDGF), unrelated to hepatocyte growth factor, is a heparin-binding protein originally purified from human hepatoma HuH-7 cells. HDGF exhibits mitogenic activities for certain hepatoma cells, fibroblasts and vascular smooth muscle cells, and angiogenic activities through nuclear targeting. Recently, HDGF was found to be a mitogen for lung epithelial cells in vitro and in vivo. This suggests that HDGF may play a critical role in the development and progression of lung cancer. We investigated, immunohistochemically, the relationship between HDGF expression and clinicopathological variables, and the prognostic significance of HDGF in 102 patients with completely resected non-small-cell lung cancer (NSCLC: 70 adenocarcinomas and 32 squamous cell carcinomas). To address the mechanism of action of HDGF, we evaluated the contribution of HDGF to tumor cell proliferation and intratumor angiogenesis using anti-Ki-67 and anti-CD31 antibodies, respectively. HDGF expression was strongly detected in the nucleus of cancer cells; the HDGF-labeling index (LI) was 20-95% (median 64.5%). There was no significant association between HDGF-expression level and clinicopathological variables. Patients with NSCLC showing a high HDGF-LI (> or =65%) had significantly worse overall and disease-free survivals than those with NSCLC showing a low HDGF-LI. Multivariate analysis revealed that HDGF is a significant independent prognostic factor, more powerful than pathological stage. Moreover, HDGF expression correlated with Ki-67-LI and intratumor microvessel density. We consider HDGF as a useful prognostic marker for patients with completely resected NSCLC and it may play a critical role in the pathobiology of lung cancer through its mitogenic and angiogenic activities. 相似文献
80.
Hiraoka K Fujimoto Y Tateaki Y Hiraoka K Horiuchi T Okano S Kinutani M Kinutani K 《Journal of assisted reproduction and genetics》2008,25(9-10):503-509
PURPOSE: To report successful pregnancies after the transfer of re-vitrified human day 7 blastocysts developed from vitrified cleaved embryos. METHODS AND RESULTS: A total of five day 7 blastocysts developed from vitrified cleaved embryos were re-vitrified and re-warmed. All of five re-vitrified day 7 blastocysts (100%) survived after warming and were transferred to three patients. Two of the women became clinically pregnant. Of these women, one woman delivered a healthy baby and the other pregnancy is ongoing at 26 weeks of gestation. CONCLUSIONS: This is the first report of successful pregnancies after the transfer of re-vitrified human day 7 blastocysts developed from vitrified cleaved embryos. 相似文献