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排序方式: 共有33条查询结果,搜索用时 46 毫秒
1.
《工程(英文)》2020,6(10):1170-1177
Diabetes and its related metabolic disorders have been reported as the leading comorbidities in patients with coronavirus disease 2019 (COVID-19). This clinical study aims to investigate the clinical features, radiographic and laboratory tests, complications, treatments, and clinical outcomes in COVID-19 patients with or without diabetes. This retrospective study included 208 hospitalized patients (≥ 45 years old) with laboratory-confirmed COVID-19 during the period between 12 January and 25 March 2020. Information from the medical record, including clinical features, radiographic and laboratory tests, complications, treatments, and clinical outcomes, were extracted for the analysis. 96 (46.2%) patients had comorbidity with type 2 diabetes. In COVID-19 patients with type 2 diabetes, the coexistence of hypertension (58.3% vs 31.2%), coronary heart disease (17.1% vs 8.0%), and chronic kidney diseases (6.2% vs 0%) was significantly higher than in COVID-19 patients without type 2 diabetes. The frequency and degree of abnormalities in computed tomography (CT) chest scans in COVID-19 patients with type 2 diabetes were markedly increased, including ground-glass opacity (85.6% vs 64.9%, P < 0.001) and bilateral patchy shadowing (76.7% vs 37.8%, P < 0.001). In addition, the levels of blood glucose (7.23 mmol·L−1 (interquartile range (IQR): 5.80–9.29) vs 5.46 mmol·L−1 (IQR: 5.00–6.46)), blood low-density lipoprotein cholesterol (LDL-C) (2.21 mmol·L−1 (IQR: 1.67–2.76) vs 1.75 mmol·L−1 (IQR: 1.27–2.01)), and systolic pressure (130 mmHg (IQR: 120–142) vs 122 mmHg (IQR: 110–137)) (1 mmHg = 133.3 Pa) in COVID-19 patients with diabetes were significantly higher than in patients without diabetes (P < 0.001). The coexistence of type 2 diabetes and other metabolic disorders is common in patients with COVID-19, which may potentiate the morbidity and aggravate COVID-19 progression. Optimal management of the metabolic hemostasis of glucose and lipids is the key to ensuring better clinical outcomes. Increased clinical vigilance is warranted for COVID-19 patients with diabetes and other metabolic diseases that are fundamental and chronic conditions.  相似文献   
2.
Training data matrix used for classification of text documents to multiple categories is characterized by large number of dimensions while the number of manually classified training documents is relatively small. Thus the suitable dimensionality reduction techniques are required to be able to develop the classifier. The article describes two-step supervised feature extraction method that takes advantage of projections of terms into document and category spaces. We propose several enhancements that make the method more efficient and faster than it was presented in our former paper. We also introduce the adjustment score that enables to correct defected targets or helps to identify improper training examples that bias extracted features.  相似文献   
3.
《Ceramics International》2016,42(15):16579-16583
Tb3+-Sm3+ co-doped Sr9Gd(PO4)5(SiO4)F2 (SGPSF) phosphors were prepared through a solid-state reaction, and their luminescence properties as well as energy transfer mechanism have been investigated in detail. The SGPSF:Tb3+, Sm3+ phosphors system could be efficiently excited at wavelengths ranging from 200 to 500 nm, which is well matched with the spectra of near ultraviolet chips. The emission of SGPSF:Tb3+, Sm3+ phosphor covers the entire visible region with sharp peaks in the blue, green, and red regions. The emission color of SGPSF:Tb3+, Sm3+ could be adjusted from green (0.275, 0.378) to red (0.519, 0.295) by controlling the doping content of Sm3+/Tb3+.  相似文献   
4.
谷胱甘肽过氧化物酶(GSH-Px),最早是在动物体内发现的一种含硒酶,近年来在许多植物中也发现了该酶的存在,并发现适当浓度的外源硒能提高GSH-Px的活性.本文以绿豆为实验材料,用NaSe2O3 作为硒源,对绿豆进行富硒处理,研究适当浓度的NaSe2O3对绿豆GSH-Px活性及绿豆中谷胱甘肽(GSH)含量的影响.结果显示:富硒处理可以促进绿豆GSH-Px的合成;无论是浸泡过程还是萌芽阶段,经富硒处理的绿豆其GSH-Px的活性都比对照样高;特别是在富硒处理5 h后,绿豆GSH-Px活性显著增加,比对照提高了59.38 %;而绿豆中GSH的含量则是先下降,后升高.  相似文献   
5.
目的 基于锌/钴双金属无限配位聚合物(Zn/Co-bimetal infinite coordination polymers, Zn/Co-ICPs)构建快速检测单增李斯特菌的纳米酶催化比色法。方法 基于Zn/Co-ICPs过氧化物模拟酶活性、核酸适配体对类酶活性的增强作用及特异性识别能力, 以3,3’,5,5’-四甲基联苯胺(3,3’,5,5’-tetramethylbenzidine, TMB)为催化显色底物, 建立Zn/Co-ICPs纳米酶催化比色法, 对Zn/Co-ICPs的形貌和结构进行表征, 并考察适配体浓度、pH、温度和反应时间等因素对催化效果的影响, 并将该方法应用于饮用水和冷冻巴沙鱼样品中单增李斯特菌的测定。结果 在优选的条件下, 单增李斯特菌的浓度与蓝色显色产物氧化型TMB (oxidized TMB, oxTMB)在652 nm处的吸光度呈负相关关系。该方法的线性范围为3.2×102~1.0×105 CFU/mL, r2为0.9964, 检出限(limit of detection, LOD)为1.5×102 CFU/mL。加标回收率为90.7%~108.7%, 相对标准偏差为0.17%~7.20%。结论 该方法无需使用复杂昂贵的仪器即可实现可视化检测, 且检测速度快、准确度高、选择性好, 在复杂样品快速分析中具有一定潜力。  相似文献   
6.
7.
High-efficient Ce3+/Tb3+ co-doped Ba3Y2B6O15 phosphors with multi color-emitting were firstly prepared, and their structural and luminescent properties were studied by XRD Rietveld refinement, emission/excitation spectra, fluorescence lifetimes as well as temperature-variable emission spectra. Upon 365?nm excitation, the characteristic blue Ce3+ band along with green Tb3+ peaks were simultaneously found in the emission spectra. Moreover, by increasing concentration of Tb3+, a blue-to-green tunable emitting color could be realized by effective Ce3+→Tb3+ energy transfer. Furthermore, all Ba3Y2B6O15: Ce3+, Tb3+ phosphors exhibit high internal quantum efficiency of ~?90%, while the temperature-variable emission spectra reveal that the phosphors possess impressive color stability as well as good thermal stability (T50 =?~?120?°C). The results indicate that these efficient color-tuning Ba3Y2B6O15: Ce3+, Tb3+ might be candidate as converted phosphor for UV-excited light-emitting diodes.  相似文献   
8.
9.
饮料和糖果中5种非法添加色素的检测   总被引:2,自引:0,他引:2  
采用聚酰胺吸附法提取样品溶液的色素,用乙醇-氨水-水混合溶液解吸,用高效液相色谱-二极管阵列检测器测定。采用ODS柱分离,以甲醇和硫酸铵溶液为流动相进行洗脱,在520nm波长处检测。亮黑、荧光素钠、红色2G、荧光桃红和孟加拉玫瑰红的质量浓度在1.0~10.0mg/L范围内与其色谱峰面积的线性关系良好(r=0.999),在1、2、5mg/kg添加水平时的平均回收率在82.95%~95.43%范围内,RSD值在1.99%~5.95%范围内。方法检出限为1.0mg/kg。该方法准确度高,分离效能好,结果稳定可靠,适合于饮料和糖果中亮黑、荧光素钠、红色2G、荧光桃红和孟加拉玫瑰红的测定。  相似文献   
10.
番石榴中总黄酮的微波萃取工艺研究   总被引:3,自引:2,他引:1       下载免费PDF全文
采用微波萃取法研究番石榴中总黄酮的提取工艺.比较了微波功率、微波时间、料液比、提取剂乙醇浓度对番石榴黄酮含量及其抗氧化能力的影响,并以微波功率、微波时间、料液比为考察因素,采用正交试验,确定了番石榴中总黄酮微波萃取的最佳工艺参数,即微波功率300W,时间15min,料液比1:40,乙醇浓度50%.在上述提取条件下,番石榴干粉中总黄酮含量可达55.56mg/g.  相似文献   
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