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Deep learning-based computer vision methods have recently made remarkable breakthroughs in the analysis and classification of cancer pathology images. However, there has been relatively little investigation of the utility of deep neural networks to synthesize medical images. In this study, we evaluated the efficacy of generative adversarial networks to synthesize high-resolution pathology images of 10 histological types of cancer, including five cancer types from The Cancer Genome Atlas and the five major histological subtypes of ovarian carcinoma. The quality of these images was assessed using a comprehensive survey of board-certified pathologists (n = 9) and pathology trainees (n = 6). Our results show that the real and synthetic images are classified by histotype with comparable accuracies and the synthetic images are visually indistinguishable from real images. Furthermore, we trained deep convolutional neural networks to diagnose the different cancer types and determined that the synthetic images perform as well as additional real images when used to supplement a small training set. These findings have important applications in proficiency testing of medical practitioners and quality assurance in clinical laboratories. Furthermore, training of computer-aided diagnostic systems can benefit from synthetic images where labeled datasets are limited (e.g. rare cancers). We have created a publicly available website where clinicians and researchers can attempt questions from the image survey ( http://gan.aimlab.ca/ ). © 2020 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.  相似文献   
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Placebo controls play a critical role in the evaluation of any pharmacotherapy. This review surveys the placebo arm in 12 randomized controlled trials (RCTs) investigating burning mouth syndrome (BMS) and documents a positive placebo response in 6 of them. On average, treatment with placebos produced a response that was 72% as large as the response to active drugs. The lack of homogeneity in the use of placebos adds to the difficulty in comparing results and aggregating data. Future RCTs investigating BMS would benefit from larger sample sizes, adequate follow‐up periods, and use of a standard placebo.  相似文献   
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In this study, Tithonia diversifolia Helms. (A Gray), Aloe secundiflora (Miller) and Azadirachta indica (A. Juss) plant extracts were used to make herbal soaps while Thevetia peruviana (Schum) seed oil was used to make a herbal lotion for skincare. The soaps were tested for the growth inhibition of Escherichia coli, and Candida albicans. The lotion was evaluated against Staphylococcus aureus and E.coli. Although Tithonia diversifolia soap exhibited the highest inhibitory effect on the test bacterial strains, it had the least inhibition against C. albicans. Results from this study indicated that the ‘Tithonia diversifolia’ soap would have superior skin protection against the tested bacteria but would offer the least skin protection against C. albicans. The herbal lotion inhibited S. aureus and E. coli in a concentration dependent manner, however, the inhibitory effect was more pronounced on S. aureus.  相似文献   
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We have applied an immunostick colorimetric enzyme-linked immunosorbent assay (ELISA) assay for the rapid authentication of grouper (Epinephelus marginatus) fillets in the fish market. An indirect ELISA has been assayed by using a monoclonal antibody (3D12) developed previously in another work. In this study, 52 commercial fish fillets samples collected from local markets and supermarkets, which were labelled as grouper, have been analysed by this methodology; only 14 samples were confirmed to be grouper. The simplicity of the procedure and the short time required for the analysis make it suitable for a screening test of a large number of samples and it can be made into a field test for fish processors and inspectors to be used on site.  相似文献   
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目的:目前有关骨髓间充质干细胞向内皮细胞诱导分化的研究较少。本实验分离和培养人骨髓间充质干细胞,用带有VEGF165的质粒转染人骨髓间充质干细胞,探讨血管内皮生长因子对其体外诱导分化的作用。 方法:实验于2005—04/2006—04在吉林大学人兽共患病教育部重点实验室完成。取成人的已排除血液系统肿瘤疾病的新鲜骨髓(自愿提供),采用Percoll梯度分离培养骨髓间充质干细胞,于倒置显微镜下观察细胞形态变化和生长情况。原代细胞培养至增殖接近融合状态时,单克隆培养法分离传代培养,扩增骨髓间充质干细胞。采用流式细胞术检测细胞免疫学表型。在原核细胞大肠杆菌DH5α中复制扩增和提取,纯化、克隆pcDNA3.0-VEGF165质粒。用脂质体转染法转染骨髓间充质干细胞:应用流式细胞术检测诱导后骨髓间充质干细胞免疫学表型变化j并采用免疫荧光染色鉴定转染情况,并设质粒空载和未转染的骨髓间充质干细胞为对照。 结果:人骨髓间充质干细胞原代培养1周后,造血细胞消失,贴壁细胞体积增大,呈现梭形外观,有粗大的细胞突起伸出。2周后细胞融合成单层,梭形突起变长,排列有明显的方向性,细胞排列成旋涡状、网状、辐射状。流式细胞术显示,人骨髓间充质干细胞免疫学表型CD44、CD29阳性,CD34、CD31、CD45阴性。VEGF165诱导骨髓间充质千细胞后CD44表达明显降低,CD31明显升高。免疫荧光染色显示,用FITC标记后的VEGF抗体使细胞显现绿色荧光,用cy3标记的CD31抗体使细胞显现了红色荧光。 结论:转染后的骨髓间充质干细胞细胞表型发生明显转变,CD31表达率明显增高,呈现典型的内皮细胞的表型特征,这说明骨髓间充质干细胞具有向内皮细胞分化的潜能。  相似文献   
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