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91.
目的:寻找金银花中的抗呼吸道病毒感染的成分,并进行定量研究。方法:采用各种柱层析和制备薄层层析等方法分离、细胞病变法进行抗病毒作用的研究,采用RP-HPLC方法进行定量方法的研究。结果:分离得到了13种咖啡酰奎宁酸类化合物和咖啡酸、咖啡酸甲酯,确认咖啡酰奎宁酸类成分具有较强的抗呼吸道病毒作用,并采用HPLC方法测定了金银花中的 6种咖啡酰奎宁酸类成分和咖啡酸的含量。结论:咖啡酰奎宁酸类成分为金银花中的有效成分,定量方法准确、重复性好。  相似文献   
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OBJECTIVE: We determined the relative value of teleradiology and radiology resident coverage of the emergency department by measuring and comparing the effects of physician specialty, training level, and image display method on accuracy of radiograph interpretation. MATERIALS AND METHODS: A sample of four faculty emergency medicine physicians, four emergency medicine residents, four faculty radiologists, and four radiology residents participated in our study. Each physician interpreted 120 radiographs, approximately half containing a clinically important index finding. Radiographs were interpreted using the original films and high-resolution digital monitors. Accuracy of radiograph interpretation was measured as the area under the physicians' receiver operating characteristic (ROC) curves. RESULTS: The area under the ROC curve was 0.15 (95% confidence interval [CI], 0.10-0.20) greater for radiologists than for emergency medicine physicians, 0.07 (95% CI, 0.02-0.12) greater for faculty than for residents, and 0.07 (95% CI, 0.02-0.12) greater for films than for video monitors. Using these results, we estimated that teleradiology coverage by faculty radiologists would add 0.09 (95% CI, 0.03-0.15) to the area under the ROC curve for radiograph interpretation by emergency medicine faculty alone, and radiology resident coverage would add 0.08 (95% CI, 0.02-0.14) to this area. CONCLUSION: We observed significant differences between the interpretation of radiographs on film and on digital monitors. However, we observed differences of equal or greater magnitude associated with the training level and physician specialty of each observer. In evaluating teleradiology services, observer characteristics must be considered in addition to the quality of image display.  相似文献   
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Oleoylethanolamide (OEA) is an endogenous lipid that contributes in important ways to the peripheral regulation of food intake. When administered intraperitoneally, OEA is a potent satiety-inducing anorexiant in rats and mice [Nature 414 (2001) 209; Neuropsycopharmacology 28 (2003) 1311; Nature 425 (2003) 90]. In the present study, we show that oral administration of OEA in pH-sensitive enteric-coated capsules produces a profound and long-lasting inhibition of food intake in free-feeding rats. This effect is accompanied by a marked elevation in OEA levels in the small intestine, but not in brain or muscle.  相似文献   
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Objective. To assess the impact of high-fidelity patient simulation on pharmacy resident knowledge, confidence, and competency with advanced resuscitation algorithms and interventions.Design. An overview of the institutional cardiopulmonary arrest algorithm and a review of pertinent medications and calculations were presented to postgraduate year 1 (PGY1) pharmacy residents, followed by participation in 3 simulated clinical scenarios using a high-fidelity mannequin.Assessment. An improvement of pharmacy resident knowledge, confidence, and competency with advanced resuscitation skills was observed. In addition, pharmacy residents demonstrated high performance levels with skills requiring advanced competency and proactive interactions with the cardiac arrest team.Conclusion. Incorporating high-fidelity patient simulation into an advanced resuscitation training program can help pharmacy residents achieve competency through the active learning of practical skills.  相似文献   
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Inhibition of the proteasome has emerged as a clinically effective anticancer therapeutic approach in recent years. Bortezomib (Velcade®) showed extremely high potency against a wide range of cancer cell lines. Ixazomib (MLN9708-MLN2238), the second-generation proteasome inhibitor, selectivity and potency were similar to that of bortezomib, is currently being investigated in phase I studies. It shows superior antitumor activity in hematologic malignancy, especially multiple myelomas. In this study, for the first time, we evaluated and compared the antiproliferative and apoptotic effects of the novel proteasome inhibitor MLN2238 (the active form of MLN9708) with bortezomib using in vitro chronic myeloid leukemia. Cytotoxic and apoptotic effects of MLN2238 and bortezomib were determined by trypan blue dye exclusion assays, WST-1 cell proliferation assay, increased AnnexinV-PI binding capacity, changes in caspase-3 activity and loss of mitochondrial membrane potential (JC-1). Associated with proteasome pathway NFκB1 and c-myc mRNA expression levels were examined by the qRT-PCR method. We observed that cytotoxic and apoptotic effects on K562 cells were started at 5?μm of MLN2238 and 1?μm of bortezomib after 24 and 48?h. Also, MLN2238 and bortezomib downregulated NFκB1 and c-myc mRNA expression at 24?h. Our result revealed that MLN22238 and bortezomib had significant cytotoxic and apoptotic effects on K562 cells. Here, we first demonstrate in vitro data that support the development of MLN2238, by direct comparison with bortezomib on K562 cells.  相似文献   
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