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Background  Machine learning (ML) has captured the attention of many clinicians who may not have formal training in this area but are otherwise increasingly exposed to ML literature that may be relevant to their clinical specialties. ML papers that follow an outcomes-based research format can be assessed using clinical research appraisal frameworks such as PICO (Population, Intervention, Comparison, Outcome). However, the PICO frameworks strain when applied to ML papers that create new ML models, which are akin to diagnostic tests. There is a need for a new framework to help assess such papers. Objective  We propose a new framework to help clinicians systematically read and evaluate medical ML papers whose aim is to create a new ML model: ML-PICO (Machine Learning, Population, Identification, Crosscheck, Outcomes). We describe how the ML-PICO framework can be applied toward appraising literature describing ML models for health care. Conclusion  The relevance of ML to practitioners of clinical medicine is steadily increasing with a growing body of literature. Therefore, it is increasingly important for clinicians to be familiar with how to assess and best utilize these tools. In this paper we have described a practical framework on how to read ML papers that create a new ML model (or diagnostic test): ML-PICO. We hope that this can be used by clinicians to better evaluate the quality and utility of ML papers.  相似文献   
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Previously, we reported that allogeneic skin grafts were rapidly rejected by CD28 and CD40 ligand double deficient mice mediated by CD8+ T cells. These results indicated that some elements in addition to CD28- and CD40-mediated costimulation provide stimulatory signals for the activation of donor-specific CD8+ T cells. In this report, we investigated the role of inflammation associated with transplantation on costimulation-independent priming of CD8+ T cell during graft rejection. B6 RAG1 KO mice were transplanted with BALB/c-skin and adoptively transferred with syngeneic CD8+ T cells the same day or 50 days after transplantation. When blockade of CD28- and CD40-mediated costimulation failed to prevent acute rejection of freshly transplanted skin grafts, it efficiently delayed rejection of well-healed skin grafts. These results showed that factors associated with transplantation have essential roles in inducing costimulation blockade-resistant allograft rejection. Costimulation blockade failed to prevent acute graft-infiltration of NK cells and increasing expression of intragraft IL-12 and IL-15. These factors may trigger the graft-infiltration and priming of CD8+ T cells to induce costimulation blockade-resistant allograft rejection.  相似文献   
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Annulo-aortic ectasia is an extremely rare complication of Gaucher's disease. We report successful surgery in a patient with Gaucher's disease complicated by annulo-aortic ectasia and aortic dissection. Cabrol's operation was accomplished without bleeding or sternal adaptation problems.  相似文献   
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Black fungi are a group of fungi that are characterized by the development of a pale brown to black color in the cell walls of their vegetative cells, conidia, or both. A mycotic infection caused by a member of black fungi can be subdivided into three clinical entities: phaeohyphomycosis, chromoblastomycosis, and mycetoma. Phaeohyphomycosis is distinguished from mycetoma by the absence of grain (organized, interwoven mycelial aggregates) formation, and from chromoblastomycosis by the absence of sclerotic bodies (thick-walled muriform cells). Phaeohyphomycosis is a rare disease and has been sporadically reported. In the present report, phaeohyphomycosis of the right thumb of a 72-year-old man was presented. A precipitating trauma of two months earlier at the site was recalled. A solitary mass, 10 mm in diameter, was gradually formed in the palm side of the distal right thumb and finally resected. Histological examination disclosed a solitary granulomatous lesion surrounded by an incomplete fibrous capsule. The lesion mainly involved subcutaneous tissue and was composed of multiple pyogranulomas. Pigmented branched septate hyphae and yeast-like cells were sparsely found in the periphery of the abscess and within histiocytic cells of the granulomas. No sclerotic cells were detected. When pigmentation of black fungi in tissue is as faint as in the present case, Fontana-Masson staining is useful to accentuate the presence of melanin-like pigment of fungal cell walls.  相似文献   
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Summary The relationship between the accumulation of isoprenaline and the incidence and duration of ventricular fibrillation was investigated in the perfused rat heart. Isolated rat hearts were perfused with 3H-isoprenaline (1 mol/l) for 30 min at a constant flow rate of 6.5 ml/min at a temperature between 40 and 41° C. Electrocardiograms were recorded during the perfusion period and the isoprenaline content of the tissue was measured after the perfusion. The accumulation of isoprenaline was significantly increased and the duration of ventricular fibrillation was significantly prolonged by the presence of tropolone (100 mol/l). When extraneuronal uptake inhibitors such as normetanephrine (100 mol/l), 3-O-methylisoprenaline (100 mol/l) or phenoxybenzamine (1 mol/l) were added to the perfusion fluid containing 3H-isoprenaline (1 mol/l) and tropolone (100 mol/l), the accumulation of isoprenaline was sifnificantly decreased, the incidence of ventricular fibrillation was significantly reduced and the duration of ventricular fibrillation was significantly shortened. There was a significant correlation for dependence of duration of ventricular fibrillation on the isoprenaline content of rat hearts perfused with various extraneuronal uptake inhibitors in the presence of tropolone (correlation coefficient [r]=0.62, P<0.001).These results indicate that the accumulation of isoprenaline in perfused rat hearts relates to the occurrence and duration of ventricular fibrillation.This study was supported in part by a Grant-in-Aid for Scientific Research (59570980) from the Ministry of Education, Science and Culture, Japan  相似文献   
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OBJECTIVE: This study was carried out to examine fetal alcohol spectrum disorders (FASD) among Japanese children of alcoholic mothers. This is the first report concerning FASD in Japan. METHODS: The subjects were 30 alcoholic women who were inpatients in the Kurihama Alcoholism Center and had given birth to children. They were subjected to a semi-structured interview by the author. Sixty healthy women who had not drunk during pregnancy were used as a control group, and they also underwent semi-structured interviews. The alcoholic women were divided into two groups, 13 who drunk during pregnancies and 17 who did not drink. Twenty children experienced of prenatal alcohol exposure and 40 children did not. The three groups; i.e., 13 alcoholic mothers who had drunk during pregnancy and their 20 children (ALD group), 17 alcoholic mothers who had not drunk during pregnancy and their 40 children (ALND group) and 60 non-alcoholic control mothers and their 80 children (Control group), were compared concerning the mothers' drinking problems and abnormal deliveries, children's birth weights, congenital abnormalities, abnormalities of the central nervous system and psychological problems. RESULTS: The mean age of onset of problem drinking of the mothers in the ALD group was significantly lower than that in the mothers of the ALND group, and some of the mothers in the ALD group showed alcohol dependence before their pregnancies. The mean birth weights of the children of the ALD group, ALND group and Control group were 2816 g, 3128 g and 3142 g, respectively and the differences were significant. The children of the ALD group had significantly more abnormal birth episodes, developmental retardation and psychiatric symptoms than those in the other two groups. Among 20 children in the ALD group, FASD was suspected in 6 children (10% of the children of alcoholic mothers). Six children had low birth weights, abnormal birth episodes, mental retardation and psychiatric symptoms. CONCLUSION: One third of the Japanese children of alcoholic mothers had experiences of prenatal alcohol exposure and 10% of them had suspected FASD abnormalities.  相似文献   
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