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1.
目的: 利用Kalman滤波-紫外分光光度法考察微波提取动力学特征, 并对其进行可视化表征。方法: 利用Kalman滤波-紫外分光光度法对微波加热的三七物质组进行提取动力学研究并与传统加热方法进行对比, 测定2组物质组提取率, 通过Matlab软件建立物质组释放及释放增量图谱, 以期能定量、整体、可视化地评价不同加热方式的物质组提取动力学特征。结果: 以三七中所有化合物为整体物质组, 对2条提取动力学曲线进行f2相似因子拟合, f2=30.002 6(<50), 因此2条释放曲线存在显著差异; 2种加热方式提取动力学均符合一级动力学模型, 说明组分释放相对同步; 微波加热物质组在180 min时提取率达到80%以上, 传统加热提取率为45%左右, 释放量显著增加。结论: 采用Kalman滤波-紫外分光光度法评价微波加热物质组提取动力学特征, 满足实验要求; 可视化评价可以直接表达出微波提取动力学特征及同步性, 微波加热使物质组释放增量显著增加, 为后期微波提取技术的工业化生产提供理论参考。  相似文献   
2.
PurposeTo investigate the safety and efficacy of an aqueous polyethylene glycol-based liquid embolic agent, Embrace Hydrogel Embolic System (HES), in the treatment of benign and malignant hypervascular tumors.Materials and MethodsA prospective, single-arm, multicenter study included 8 patients, 5 males and 3 females, with a median age of 58.5 years (30–85 years), who underwent embolization in 8 tumors between October 2019 and May 2020. Technical success was defined as successful delivery of HES to the index vessel, with disappearance of >90% of the targeted vascular enhancement or, for portal vein embolization, occlusion of the portal branches to the liver segments for future resection. The volume of HES administered, ease of use (5 point Likert scale), administration time, and adverse events (AEs) were recorded. Evaluation was performed at 7, 30, and 90 days via clinical assessment and blood testing, and follow-up imaging was performed at 30 days.ResultsEight patients were enrolled, and 10 embolizations were performed in 8 lesions. Tumors included hepatocellular carcinoma (n = 4), renal angiomyolipoma (n = 3), and intrahepatic cholangiocarcinoma (n = 1). Technical success was 100%, and the average ease of use was 3.3 ± 1.0 SD. The HES delivery time was 1–28 minutes (median, 16.5 minutes), and the HES volume injected was 0.4–4.0 mL (median, 1.3 mL). All patients reached 30-day follow-up with imaging, and 6 patients reached 90-day follow-up. There were 3 serious AEs in 2 patients that were unrelated to the embolic agent.ConclusionHES resulted in a 100% embolization technical success rate. The product ease of use was acceptable, and no target vessel recanalization was noted on follow-up imaging at 30 days.  相似文献   
3.
The use of phase change materials (PCMs) is an attractive method for energy storage and utilization in building envelopes. Here, shape-stabilized phase change materials (SS-PCMs) were prepared via direct adsorption using mesoporous silica (MS) with different pore diameters as the support matrix. The leakage properties, microstructure, chemical structure, thermophysical properties, activation energy, thermal stability and thermal storage-release characteristics of paraffin and SS-PCMs were investigated. The results show that the maximum mass proportion of paraffin in SS-PCMs is 70% when the average pore diameter of mesoporous silica is 15 nm, and the phase change temperature and latent heat of the corresponding SS-PCM are 23.6 °C and 135.4 kJ/kg, respectively. No chemical reaction occurs between mesoporous silica and paraffin and the SS-PCMs exhibit high thermal stability. The high activation energy of the paraffin (70%)/MS1 SS-PCM verifies that the shape and thermal properties can be maintained stably during phase change conversions. The time required for SS-PCMs to complete the thermal storage and release process is reduced by up to 34.0% compared with that for pure paraffin, showing a decline in the thermal conductivity of SS-PCMs after the addition of mesoporous silica. Hence, the prepared paraffin/MS SS-PCMs, in particular paraffin (70%)/MS1 SS-PCM, can be used for storing thermal energy and regulating indoor temperature in buildings.  相似文献   
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正胰十二指肠切除术(pancreaticoduodenectomy,PD)及胰体尾切除术(distal pancreatectomy, DP)作为治疗壶腹周围及胰体尾肿瘤的经典术式,具有手术难度大、技术要求高及术后并发症多等特点,是腹部外科极具代表性及挑战性的术式之一。随着手术理念、技术及缝合材料的更新、进步与优化,PD术后围手术期死亡率已降至3%以下,但术后并发症特别是胰瘘的发生率仍高达10%~30%。  相似文献   
6.
曾建国  杨子墨 《中国现代中药》2021,23(12):2031-2036
湖南省历经8年聚力打造“湘九味”中药材品牌,已逐渐形成品牌品种引领的产业链发展模式。为达成湖南省中药材产业链千亿发展目标,梳理了“湘九味”品牌培育历程,厘清并阐释了相关概念,分析了产业发展现状及问题,研判了大健康应用背景下未来的中药材产业的发展趋势,并提出相关发展建议。  相似文献   
7.
中药质量控制一直是中药临床需求和产业发展的关键。刘昌孝院士于2016年提出的中药质量标志物(quality marker,Q-Marker)新概念和核心理论,建立了中药质量控制系列共性关键技术,构建了中药质量研究新模式,为中药品种的现代化研究指明了方向。以痹祺胶囊药效学、药动学研究为实例,在Q-Marker理论的指导下,从特有性、可测性、有效性和中药理论关联性等方面对痹祺胶囊的研究进行总结分析,发现士的宁、马钱子碱、甘草苷、丹酚酸B、甘草酸、隐丹参酮和丹参酮IIA可作为该复方的Q-Marker,为痹祺胶囊的质量控制及二次开发提供基础和依据,同时,也为建立痹祺胶囊的全程质量控制及质量可溯源体系奠定良好基础。  相似文献   
8.
Ti-6Al-4V is an alloy that has a high strength-to-weight ratio. It is known as an alpha-beta titanium alloy with excellent corrosion resistance. This alloy has a wide range of applications, e.g., in the aerospace and biomedical industries. Examples of alpha stabilizers are aluminum, oxygen, nitrogen, and carbon, which are added to titanium. Examples of beta stabilizers are titanium–iron, titanium–chromium, and titanium–manganese. Despite the exceptional properties, the processing of this titanium alloy is challenging when using conventional methods as it is quite a hard and tough material. Nonconventional methods are required to create intricate and complex geometries, which are difficult with the traditional methods. The present study focused on machining Ti-6Al-4V using wire electrical discharge machining (WEDM) and conducting numerous experiments to establish the machining parameters. The optimal setting of the machining parameters was predicted using a multiresponse optimization technique. Experiments were planned using the response surface methodology (RSM) technique and analysis of variance (ANOVA) was used to determine the significance and contribution of the input parameters to changes in the output characteristics (cutting speed and surface roughness). The cutting speed obtained during the processing of the annealed titanium alloy using WEDM was quite large as compared to the cutting speed obtained in the case of processing the pure, quenched, and hardened titanium alloys using WEDM. The maximum cutting speed obtained while processing the annealed titanium alloy was 1.75 mm/min.  相似文献   
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Diabetic wounds (DWs) are a common complication of diabetes mellitus; DWs have a low cure rate and likely recurrence, thus affecting the quality of patients’ lives. As traditional therapy cannot effectively improve DW closure, DW has become a severe clinical medical problem worldwide. Unlike routine wound healing, DW is difficult to heal because of its chronically arrested inflammatory phase. Although mesenchymal stem cells and their secreted cytokines can alleviate oxidative stress and stimulate angiogenesis in wounds, thereby promoting wound healing, the biological activity of mesenchymal stem cells is compromised by direct injection, which hinders their therapeutic effect. Hydro-gels form a three-dimensional network that mimics the extracellular matrix, which can provide shelter for stem cells in the inflammatory microenvironment with reactive oxygen species in DW, and maintains the survival and viability of stem cells. This review summarizes the mechanisms and applications of stem cells and hydrogels in treating DW; additionally, it focuses on the different applications of therapy combining hydrogel and stem cells for DW treatment.  相似文献   
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