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Purpose The mechanism underlying the immunomodulation caused by blood transfusion has yet to be elucidated. The aim of the present study was to determine whether the transfusion of a soluble or insoluble factor present in stored blood can induce immunomodulation, which would thereby promote solid tumor growth.Methods C57Bl/6J mice were subcutaneously inoculated with B16-CG melanoma cells, which secrete -human chorionic gonadotropin (-hCG). Following inoculation, each of three different products of allogeneic and syngeneic blood were transfused on days 0 and 1: fresh whole blood, stored whole blood, and supernatants from the stored blood. Tumor growth was then monitored by measuring urinary -hCG. All mice were killed on day 15, and the tumor weight and volume were measured.Results Transfusion of all allogeneic blood products enhanced tumor growth, as did the stored syngeneic whole blood. Neither fresh syngeneic blood nor the supernatant from stored syngeneic blood promoted tumor growth. Although the tumors were not visually detectable until day 10 after inoculation, by day 7 the levels of urinary -hCG were significantly higher in the mice that received allogeneic blood supernatant than in the mice that received saline.Conclusions A soluble alloantigen enhances solid tumor growth, as does an insoluble factor present in stored syngeneic whole blood. The immunomodulation associated with this factor begins to enhance tumor growth within 7 days after transfusion.  相似文献   
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The accurate calculation of hepatic volume by computed tomography (CT) or magnetic resonance (MR) is complicated by the need for breath holding and the injection of contrast media. These are often contraindicated in patients with liver failure, and we examined the ability of unenhanced 3-dimensional (3-D) navigator-echo-based MR (NE-MR) to accurately image livers and measure volumes without breath holding compared to unenhanced (plain) or gadolinium-diethylene triamine pentaacetic acid enhanced MR (Gd-MR) in miniature swine (n = 8). Without breath holding, diaphragm movement monitoring with NE-MR reduced motion artifacts in hepatic images compared with the other modalities. Without the injection of contrast media, the signal-to-noise ratios of the images obtained using NE-MR were significantly higher than those from plain MR; Gd-MR was superior to NE-MR, however (79.5 +/- 7.5 vs. 63.2 +/- 6.0 or 97.8 +/- 8.1, respectively; P < 0.01 for each). Overall, NE-MR produced improved high-resolution liver images. Consequently, liver volumes calculated based on NE-MR images were more highly correlated with actual liver weights compared to plain or Gd-MR in the whole livers (n = 8; r = 0.937 vs. 0.835 or 0.904, respectively). Also, NE-MR demonstrated significantly strong correlation between actual weights and volumetry-calculated volumes in regenerative livers 7 days after massive hepatectomy (n = 10, r = 0.989, P < 0.01). In conclusion, our results indicate that without breath holding or the injection of contrast media, 3-D NE-MR can provide both high-resolution liver images and precise hepatic volumes in patients with liver failure due to liver surgery (massive hepatectomy and living donor liver transplantation) or fulminant hepatic failure.  相似文献   
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To investigate effects of the preautografting administration of rituximab on the mobilization and engraftment of peripheral blood stem cells (PBSC), we retrospectively analyzed the outcomes of 43 newly diagnosed diffuse-large B-cell lymphoma patients who received CHOP chemotherapy with or without rituximab as a first-line treatment before autologous PBSC transplantation (PBSCT). There was no difference in the number of CD34(+) cells among PBSC between the non-rituximab and the rituximab groups. Although B-cells were completely depleted from PBSC in the rituximab group, we found no difference in the expression of CXCR-4, VLA-4 and c-Kit on PBSC, indicating that rituximab did not affect the expression of these adhesion molecules, which might be involved in the mechanism of mobilization. There was no significant difference in the recovery of neutrophils and platelets, transplant-related toxicity and post-transplant complications between the two groups. Despite the short follow-up, there was no significant difference in progression-free survival between the two groups. These results indicated no adverse effect of rituximab on the mobilization and engraftment of PBSC. Larger studies are required to determine the impact of rituximab on the mobilization and function of PBSC as well as whether a survival advantage exists in patients who undergo auto-PBSCT with rituximab.  相似文献   
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Fuel cells are expected to serve as next-generation energy conversion devices owing to their high energy density, high power, and long life performance. The oxygen reduction reaction (ORR) is important for determining the performance of fuel cells; therefore, using catalysts to promote the ORR is essential for realizing the practical applications of fuel cells. Herein, we propose Nb-incorporated TiO2 as a suitable alternative to conventional Pt-based catalysts, because Nb doping has been reported to improve the conductivity and electron transfer number of TiO2. In addition, Nb-incorporated TiO2 can induce the electrocatalytic activity for the ORR. In this paper, we report the synthesis method for Nb-incorporated TiO2 through a hydrothermal process with and without additional load pressures. The electrocatalytic activity of the synthesized samples for the ORR was also demonstrated. In this process, the samples obtained under various load pressures exceeding the saturated vapor pressure featured a high content of Nb and crystalline TiNb2O7, resulting in an ellipsoidal morphology. X-ray diffraction results also revealed that, on increasing the Nb doping amounts, the diffraction peak of the anatase TiO2 shifted to a lower angle and the full width at half maximum decreased. This implies that the Ti atom is exchanged with the Nb atom during this process, resulting in a decrease in TiO2 crystallinity. At a doping level of 10%, Nb-incorporated TiO2 exhibited the best electrocatalytic activity in terms of the oxygen reduction current (iORR) and onset potential for the ORR (EORR); this suggests that 10% Nb-doped samples have the potential for enhancing electrocatalytic activity.  相似文献   
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AIM:To evaluate whether an endoscopy position detecting unit(UPD-3) can improve cecal intubation rates, cecal intubation times and visual analog scale(VAS) pain scores, regardless of the colonoscopist's level of experience.METHODS:A total of 260 patients(170 men and 90women)who underwent a colonoscopy were divided into the UPD-3-guided group or the conventional group(no UPD-3 guidance).Colonoscopies were performed by experts(experience of more than 1000colonoscopies)or trainees(experience of less than 100colonoscopies).Cecal intubation rates,cecal intubation times,insertion methods(straight insertion:shortening the colonic fold through the bending technique;roping insertion:right turn shortening technique)and patient discomfort were assessed.Patient discomfort during the endoscope insertion was scored by the VAS that was divided into 6 degrees of pain.RESULTS:The cecum intubation rates,cecal intubation times,number of cecal intubations that were performed in15 min and insertion methods were not significantly different between the conventional group and the UPD-3-guided group.The number of patients who experienced pain during the insertion was markedly less in the UPD-3-guided group than in the conventional group.Univariate and multivariate analysis showed that the following factors were associated with lower VAS pain scores during endoscope insertion:insertion method(straight insertion)and UPD-3guidance in the trainee group.For the experts group,univariate analysis showed that only the insertion method(straight insertion)was associated with lower VAS pain scores.CONCLUSION:Although UPD-3 guidance did not shorten intubation times,it resulted in less patient painduring endoscope insertion compared with conventional endoscopy for the procedures performed by trainees.  相似文献   
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