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981.
Dorina Gabriella Dob Zsfia Nmeth Bence Sipos Martin Cseh Edina Pallagi Dniel Berkesi Gbor Kozma Zoltn Knya Ildik Cska 《Molecules (Basel, Switzerland)》2022,27(5)
This study aimed to produce thermosensitive liposomes (TSL) by applying the quality by design (QbD) concept. In this paper, our research group collected and studied the parameters that significantly impact the quality of the liposomal product. Thermosensitive liposomes are vesicles used as drug delivery systems that release the active pharmaceutical ingredient in a targeted way at ~40–42 °C, i.e., in local hyperthermia. This study aimed to manufacture thermosensitive liposomes with a diameter of approximately 100 nm. The first TSLs were made from DPPC (1,2-dipalmitoyl-sn-glycerol-3-phosphocholine) and DSPC (1,2-dioctadecanoyl-sn-glycero-3-phosphocholine) phospholipids. Studies showed that the application of different types and ratios of lipids influences the thermal properties of liposomes. In this research, we made thermosensitive liposomes using a PEGylated lipid besides the previously mentioned phospholipids with the thin-film hydration method. 相似文献
982.
宁波市饮用水中重金属污染物镉健康风险评价 总被引:2,自引:0,他引:2
滕丽华 《广东微量元素科学》2007,14(9):44-46
对宁波市区内36个监测点的饮用水中Cd的质量浓度进行了调查研究,并应用目前美国环保局推荐的健康风险评价模型对各区饮用水中Cd所引起的健康风险度作了初步评价。结果表明,宁波市区镉的平均质量浓度范围为0~3.2μg/L;通过饮水途径所引起的致癌健康风险中Cd在邱隘的致癌风险最大(8.7×10-6.a-1),但低于国际辐射防护委员会(ICRP)推荐的通过饮水途径最大可接受风险水平(5×10-5.a-1)。由于邱隘地区饮用水中的镉风险度相对较高,因此应优先对其进行管理。总体来说,Cd的个人年风险在10-6水平,所以宁波市通过饮水所引起的慢性镉暴露不会对暴露人群引起健康危害。 相似文献
983.
本文比较动态增强磁共振成像(DCE-MRI)与16层螺旋CT(MSCT)对小肾癌诊断及术前评估中的价值.选取64例疑似小肾癌患者作为研究对象,均接受DCE-MRI与MSCT检查.以术后病理结果为参照,比较DCE-MRI和MSCT检查对小肾癌诊断及术前评估的灵敏度、特异度和准确度,并分析这两种检查的参数与Fuhrman分... 相似文献
984.
头盔显示器在视空间性能评价中的眼睛转动问题研究 总被引:1,自引:0,他引:1
以一款由Erfle目镜为目视系统的头盔显示器为例,给出了眼睛转动时其视空间的性能评价方法、计算公式和评价结果.评价内容包括MTF、调节、像散、横向色差和畸变.对眼睛转动和不转动情况下的结果进行了分析比较:由于转动,使得某些视场的MTF 、调节等性能指标严重变差,成清晰像的范围明显减小;系统的性能出现了明显的非对称性.结果表明:无法根据眼睛不转动情况下的系统性能来判断转动情况下的性能,而只能通过实际的光线追迹才能获得. 相似文献
985.
986.
Menglin Duan Dr. Edward O'Dwyer Prof. David C. Stuckey Dr. Miao Guo 《ChemistryOpen》2019,8(8):1109-1120
To enable a more sustainable wastewater treatment processes, a transition towards resource recovery methods that have minimal environmental impact while being financially viable is imperative. Phosphorus (P) is a finite resource that is being discharged into the aqueous environment in excessive quantities. As such, understanding the financial and environmental effectiveness of different approaches for removing and recovering P from wastewater streams is important to reduce the overall impact of wastewater treatment. In this study, a process-systems modelling framework for comprehensively evaluating these approaches in terms of both economic and environmental impacts is developed. Applying this framework, treatment pathways are designed, simulated and analysed to determine the most suitable approaches for P removal and recovery. The purpose of this methodology is not only to assist with plant design, but also to identify the principal economic and environmental factors acting as barriers to implementing a given technology, incorporating the impact of waste recovery. The results suggest that the chemical and ion-exchange approaches studied deliver sustainable advantages over biological pathways, both economically and environmentally, with each possessing different strengths. The assessment methodology developed enables a more rational and environmentally sound wastewater plant design approach to be taken. 相似文献
987.
988.
利用2000~2016年登陆华南地区的24个台风样本的灾情与致灾源数据,建立台风灾害风险评估模型。首先,运用层次分析法和熵权法构建一种新的组合权重;然后,利用组合权重构建灾情指数序列和致灾源指数序列,计算每个台风灾害风险值,并将风险值从小到大划分为五个区间;最后,采用模糊随机方法建立华南地区台风灾害模糊风险评估模型,计算得到五个风险等级区间的模糊可能性,以此来表示各等级台风灾害发生的可能性大小。结果表明,基于组合权重构造的灾情指数序列与致灾源指数序列相关性较强;华南地区发生第二风险等级台风灾害的可能性最大,发生第五风险等级台风灾害的可能性最小,与实际情况较为吻合。 相似文献
989.
Mohamed W. Attwa Hany W. Darwish Nasser S. Al-Shakliah Adnan A. Kadi 《Molecules (Basel, Switzerland)》2021,26(9)
The concurrent use of oral encorafenib (Braftovi, ENF) and binimetinib (Mektovi, BNB) is a combination anticancer therapy approved by the United States Food and Drug Administration (USFDA) for patients with BRAFV600E/V600K mutations suffering from metastatic or unresectable melanoma. Metabolism is considered one of the main pathways of drug elimination from the body (responsible for elimination of about 75% of known drugs), it is important to understand and study drug metabolic stability. Metabolically unstable compounds are not good as they required repetitive dosages during therapy, while very stable drugs may result in increasing the risk of adverse drug reactions. Metabolic stability of compounds could be examined using in vitro or in silico experiments. First, in silico metabolic vulnerability for ENF and BNB was investigated using the StarDrop WhichP450 module to confirm the lability of the drugs under study to liver metabolism. Second, we established an LC–MS/MS method for the simultaneous quantification of ENF and BNB applied to metabolic stability assessment. Third, in silico toxicity assessment of ENF and BNB was performed using the StarDrop DEREK module. Chromatographic separation of ENF, BNB, and avitinib (an internal standard) was achieved using an isocratic mobile phase on a Hypersil BDS C18 column. The linear range for ENF and BNB in the human liver microsome (HLM) matrix was 5–500 ng/mL (R2 ≥ 0.999). The metabolic stabilities were calculated using intrinsic clearance and in vitro half-life. Furthermore, ENF and BNB did not significantly influence each other’s metabolic stability or metabolic disposition when used concurrently. These results indicate that ENF and BNB will slowly bioaccumulate after multiple doses. 相似文献
990.