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AIM: To evaluate the incidence, nature and prognosis of multiple primary malignancies involving renal cell carcinoma (RCC) in Japan. METHODS: Between 1975 and 1998, 319 patients underwent an operation for RCC at Hokkaido University, Sapporo, Japan. The incidence of other primary malignancies was determined and classified as antecedent, synchronous or subsequent. Follow-up was obtained by thorough chart review or telephone interview, and ranged from 0 to 276 months (median 49.0 months). To analyze the influence of other primary malignancies on prognosis, overall and cause-specific survival rates of the patients with an antecedent or synchronous malignancy were compared to the remaining patients. RESULTS: Of the 319 patients there was at least one other malignancy in 38 patients (12%). Four patients had two other malignancies. The other malignancies were antecedent in 13, synchronous in 19 and subsequent in 10 patients. Twenty-two patients had gastrointestinal cancer. In cases of antecedent or synchronous diagnosis of other primary malignancies, RCC was commonly incidental, small or low-stage. Multivariate analysis using Cox's proportional hazards model showed that, for overall survival, the presence of other antecedent or synchronous malignancies was the second most significant prognostic factor, following the pathological stage of RCC. CONCLUSIONS: In Japanese patients with RCC, the incidence of other primary malignancies was not uncommon and these malignancies contributed to the prognosis of these patients. Therefore, the malignant potential of individual tumors should be paid careful attention in the management of these patients.  相似文献   
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Background and Aims:  Increased numbers and enhanced functions of peripheral neutrophils have been observed in obstructive jaundice. However, the effects of obstructive jaundice on the bone marrow, that is neutrophil production and acquisition of neutrophil chemotactic activity, have been poorly understood. In the present study, differentials of bone marrow cells and chemotactic activity of bone marrow neutrophils were evaluated in bile duct-obstructed rats.
Methods:  Male Wistar rats underwent either bile duct obstruction for 10 days or bile duct obstruction for 4 days followed by 6 days' internal biliary drainage. Differentials of peripheral blood and bone marrow cells were sequentially determined. Chemotactic activity of peripheral and bone marrow neutrophils was evaluated with a modified Boyden method using interleukin-8 (recombinant rat Gro-β) as a chemoattractant.
Results:  Numbers of peripheral neutrophils significantly increased after bile duct obstruction. Significant increases in the myeloid/erythroid (M/E) ratio of bone marrow cells were observed after bile duct obstruction. The neutrophil proliferative pool (promyelocytes and myelocytes) increased initially, followed by an increased neutrophil storage pool (metamyelocytes, bands, and segmented neutrophils). The M/E ratio as well as the neutrophil proliferative and storage pools normalized after internal biliary drainage. Chemotactic activity was enhanced in both peripheral and bone marrow neutrophils after bile duct obstruction, and enhanced chemotaxis was alleviated with internal biliary drainage.
Conclusion:  The present results strongly suggest the principal role of the bone marrow in increasing the number of neutrophils and their chemotactic activity during obstructive jaundice.  相似文献   
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甲硝唑诱导阴道毛滴虫凋亡样细胞死亡   总被引:1,自引:0,他引:1  
目的凋亡或程序性细胞死亡在多细胞生物体中已经被广泛研究,然而,关于单细胞寄生性原生动物细胞凋亡发生的分子机制却知之甚少。本研究旨在了解甲硝唑诱导阴道毛滴虫细胞凋亡的特征。方法培养阴道毛滴虫并用不同浓度的甲硝唑进行处理。在不同的时间间隔进行活细胞计数。提取甲硝唑处理过的阴道毛滴虫基因组进行DNA断裂片段检测。用DNA断端末端标记(TUNEL)法测定甲硝唑处理后阴道毛滴虫核酸内切酶活性。流式细胞检测分析脂酰丝氨酸暴露情况。结果甲硝唑可以诱导阴道毛滴虫出现凋亡样细胞死亡。这种凋亡样细胞死亡表现为细胞皱缩,磷脂酰丝氨酸暴露以及核染色体凝聚,但并未检测到寡核苷酸DNA梯带。结论阴道毛滴虫程序性细胞死亡的调节通路不同于多细胞生物体。确定导致原生动物细胞死亡的凋亡通路也许最终可用于鉴定新的治疗靶点。  相似文献   
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Mesenchymal-epithelial interactions are important in the gastric mucosal repair. However, specific factors responsible for such interactions have not been established. In the present study, keratinocyte growth factor (KGF) significantly stimulated proliferation of gastric epithelial cells dose dependently and synergistically with hepatocyte growth factor (HGF), epidermal growth factor (EGF) and insulin. Restitution of gastric epithelial monolayers was also assessed, using a round wound restitution model. Keratinocyte growth factor facilitated the restitution of gastric epithelial cells significantly but did not have any effects on gastric fibroblasts. Keratinocyte growth factor receptor mRNA was expressed by gastric epithelial cells, indicating that these effects were elicited by the specific receptor mediated pathway. Northern blot analysis revealed the expression of KGF mRNA in gastric fibroblasts but not in gastric epithelial cells, indicating the production of KGF. These results suggest that KGF might be involved in gastric mucosal repair, through mesenchymal-epithelial interaction.  相似文献   
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Objective

This study investigated the marginal and internal adaptation of individual dental crowns fabricated using a CAD/CAM system (Sirona’s BlueCam), also evaluating the effect of the software version used, and the specific parameter settings in the adaptation of crowns.

Material and Methods

Forty digital impressions of a master model previously prepared were acquired using an intraoral scanner and divided into four groups based on the software version and on the spacer settings used. The versions 3.8 and 4.2 of the software were used, and the spacer parameter was set at either 40 μm or 80 μm. The marginal and internal fit of the crowns were measured using the replica technique, which uses a low viscosity silicone material that simulates the thickness of the cement layer. The data were analyzed using a Friedman two-way analysis of variance (ANOVA) and paired t-tests with significance level set at p<0.05.

Results

The two-way ANOVA analysis showed the software version (p<0.05) and the spacer parameter (p<0.05) significantly affected the crown adaptation. The crowns designed with the version 4.2 of the software showed a better fit than those designed with the version 3.8, particularly in the axial wall and in the inner margin. The spacer parameter was more accurately represented in the version 4.2 of the software than in the version 3.8. In addition, the use of the version 4.2 of the software combined with the spacer parameter set at 80 μm showed the least variation. On the other hand, the outer margin was not affected by the variables.

Conclusion

Compared to the version 3.8 of the software, the version 4.2 can be recommended for the fabrication of well-fitting crown restorations, and for the appropriate regulation of the spacer parameter.  相似文献   
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