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41.
We investigated the effects of β-glucan purified from Paenibacillus polymyxa JB115 on the viability and proliferation of splenocytes. Splenocytes play a critical role in host immunity. MTT assays and trypan blue exclusion tests revealed that β-glucan significantly promoted the viability and proliferation of splenocytes over a range of concentrations. However, there was no specific subset change. β-glucan protected splenocytes from cytokine withdrawal-induced spontaneous cell death. For further mechanistic studies, ELISA assay revealed that β-glucan enhanced the expression of anti-apoptotic molecules and interleukin 7 (IL-7), a cytokine critical for lymphocyte survival. We also investigated the IL-2 dependency of β-glucan-treated splenocytes to determine if treated cells could still undergo clonal expansion. In flow cytometric analysis, β-glucan induced increased levels of the activation marker CD25 on the surface of splenocytes and β-glucan-treated splenocytes showed higher proliferation rates in response to IL-2 treatment. This study demonstrates that β-glucan can enhance the survival of splenocytes and provides valuable information to broaden the use of β-glucan in research fields.  相似文献   
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There are limitations to the sensitivity and specificity of conventional two-dimensional echocardiograms in making an accurate diagnosis in certain patient populations. This led to the development of specific contrast-enhancing agents with the following characteristics: small enough to cross the pulmonary capillary bed, remain stable throughout the length of the procedure, do not dissolve in blood, and rapidly cleared from the body with low toxicity. Unfortunately, the use of contrast echocardiography has not taken off as expected. The low take-up rate among clinicians can largely be attributed to the black box warning by the United States Food and Drug Administration in 2007, after the coincidental occurrence of four patient deaths and about 190 severe cardiopulmonary reactions shortly after contrast agent administration. In this article, we address the clinical safety of contrast agents, share our institution’s experience in using it and elaborate on the clinical indications of contrast echocardiography.  相似文献   
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Background  

Endoscopic resection as curative treatment of early gastric cancer (EGC) requires accurate staging for depth of invasion (T) before therapy. This study aimed to compare T staging of EGC using a miniprobe with that of conventional endoscopy (CE).  相似文献   
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Right hepatectomy with the middle hepatic vein (MHV) affects venous return and function of the remaining liver. We compared the remnant liver volume in the donors of resection with or without the MHV on the remnant liver volume regeneration. Living donors who had undergone right hepatectomy without MHV (RH group; n = 36) and those with MHV (ERH group; n = 19) were reviewed. Volume regeneration of segments I-III, segment IV, and total remnant liver volume was assessed at postoperative day (POD) 7 and 30 using a computed tomography-based volumetry program. According to the measured volume data, we calculated the liver remnant volume and the rate of liver remnant volume increase. The regeneration rate of segment IV was significantly low in the ERH group compared with that in the RH group at POD 7 and POD 30 (160% vs 141%; P = .018 and 189% vs 154%; P = .007). In contrast, the regeneration rate of the total remnant liver volume was not significantly different between the 2 groups (173% vs 175%; P = .758 and 199% vs 198%; P = .880). In conclusion, extended right hepatectomy can be safely performed with careful preoperative evaluation without significant impairment of remnant liver regeneration.  相似文献   
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