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31.
尿中甲酸与乙酸经浓硫酸催化生成甲酸乙酯,经FFAP/101白色担体分离,当甲酸含量在(1.0-500)mg/L范围内有良好的线性关系。得到回归方程y=0.8077.6x 480.6,相关系数为0.9997。结果表明,该方法简便、准确、灵敏度高。  相似文献   
32.
冷冻浓缩-RO工艺处理空间站尿液试验研究   总被引:4,自引:0,他引:4  
尿液废水的处理是空间站再生式环境控制与生命保障系统的重要环节.以尿液为分析目标,考察了单/多级冷冻浓缩对尿液的预处理效果,以及反渗透膜对融冰的深度处理效果,并进行了能耗分析.结果表明,冷冻浓缩能高效地去除尿液中各种杂质,仅经单级处理,即可去除原尿液97%以上的氨氮、有机物和91%以上的盐;反渗透装置对进水中的盐和氨氮有良好的去除效果,各级融冰经反渗透膜过滤后,出水水质均可满足杂用水的水质标准;综合考虑能耗和出水水质,认为两级冷冻浓缩与反渗透的组合工艺更能体现该工艺高效低耗的特征.  相似文献   
33.
尿检仪是非常重要的医学诊断设备,然而传统的尿检仪从原理设计上具有很大的局限性.针对常规尿检仪具有体积大、成本高等缺点,研究了基于电容式传感器的尿检原理,设计了一种便携式无线尿检仪.系统以电容式生物传感器TouchSensor为检测元件并通过ACAM公司的Pcap01检测其各单元电容变化,采用意法半导体公司的32位低功耗微控制器STM32L152,通过Dialog公司的低功耗蓝牙芯片DA14580进行无线通信.为了获得精准的电容值,提出了一种基于拉依达准则的数据处理算法.实验结果表明该尿检仪具有精度高、灵活性强等特点.  相似文献   
34.
传统城市排水模式存在混合稀释、末端处理、高耗水、高污染、资源流失等特征及缺陷.分质负压排水技术将污染程度不同的生活废水分开收集并单独处理,实现生活污水的源头控制与资源回收,符合可持续发展理念.文章对某研发基地A车间进行了分质负压排水方案设计,粪便水和尿液分别经过处理后可作为农田绿色肥料,而经处理后的杂排水亦可用于人工湿地景观水.另外,该方案中采用的负压粪尿分离便器比节水便器节省约90%冲厕水,能最大程度地实现节水;同时回收利用尿液中的N、P等营养元素与粪便中的有机物等营养物质,有效避免富营养化问题.经估算,该分质负压排水系统每天可节约用水约11 m3,每年节约水资源费用约1.6万元.  相似文献   
35.
Renal cell carcinoma (RCC) is the third most frequent urinary malignancy and one of the most lethal. Current diagnostic and follow-up techniques are harmful and unspecific in low-grade tumors. Novel minimally invasive markers such as urine microRNAs (miRNAs) are under study. However, discrepancies arise among studies in part due to lack of consent regarding normalization. We aimed to identify the best miRNA normalizer for RCC studies performed in urine samples together with a miRNA profile with diagnostic value and another for follow-up. We evaluated the performance of 120 candidate miRNAs in the urine of 16 RCC patients and 16 healthy controls by RT-qPCR followed by a stability analysis with RefFinder. In this screening stage, miR-20a-5p arose as the most stably expressed miRNA in RCC and controls, with a good expression level. Its stability was validated in an independent cohort of 51 RCC patients and 32 controls. Using miR-20a-5p as normalizer, we adjusted and validated a diagnostic model for RCC with three miRNAs (miR-200a-3p, miR-34a-5p and miR-365a-3p) (AUC = 0.65; Confidence Interval 95% [0.51, 0.79], p = 0.043). let-7d-5p and miR-205-5p were also upregulated in patients compared to controls. Comparing RCC samples before surgery and fourteen weeks after, we identified let-7d-5p, miR-152-3p, miR-30c-5p, miR-362-3p and miR-30e-3p as potential follow-up profile for RCC. We identified validated targets of most miRNAs in the renal cell carcinoma pathway. This is the first study that identifies a robust normalizer for urine RCC miRNA studies, miR-20a-5p, which may allow the comparison of future studies among laboratories. Once confirmed in a larger independent cohort, the miRNAs profiles identified may improve the non-invasive diagnosis and follow-up of RCC.  相似文献   
36.
The Giant panda communicates with conspecifics by depositing a mixture of volatile compounds (called scent marks) on trees and rocks. Using mass spectrometry, we identified 951 chemical components from scent glands, urine, vaginal secretions, and scent marks made by pandas. The scent marks of the two genders contained a similar array of chemicals but varied in concentration; specifically, males possessed a significantly greater amount of short chain fatty acids (F(1, 29) = 18.4, P = 0.002). Using stepwise discriminate analysis on the relative proportions of a subset of these chemicals, it was possible to classify gender (94% for males and females) and individuality (81% for males and 91% for females) from scent marks. The power to identify individual males was reduced due to the relatedness of two subjects. By cracking the identity code of Giant panda communication, we show insights into how these animals can match individuals with unique chemical profiles. Since radiocollaring is currently banned in China, the techniques described in this paper give field biologists a new means to identify and track pandas in the wild.  相似文献   
37.
In this study, we report the development of adsorptive extraction materials by surface protein-imprinted polymers (MIPs) over silica gel for selective recognition/separation of human serum albumin (HSA) from urine. The HSA-imprinted polymers prepared on silica particle had at interface between the silica gel and different MIPs greatly produced enrichment for the binding of protein from the urine. The solid-phase extraction of the optimized polymer layer was prepared by copolymerization of methacrylic acid (MAA), acrylamide (AAm), and dimethylaminoethylmethacrylate (DMAEMA) and a crosslinker methylenebisacrylamide (MBA) at the mole ratio of 1:158:88 (T:M:C) and showed moderate affinity (<104 order M−1) toward target protein HSA and selectivity. Four analogues, egg white albumin (EWA), bovine serum albumin (BSA), lysozyme (Lyz), and creatinine (Cre) were selected to study the binding efficiency of MIPs in single and binary protein solutions. We studied the influence on recognition ability for HSA and found that prepolymer mixture and matrix flexibility of the optimized thin polymer layer (35 ± 10 nm) on the submicrosilica particles. The high-binding affinity (QMIP, 86.7 mg g−1) and fast kinetics (180 min) were observed for this synthesized HSA-MIP when compared with other reported HSA-MIPs in surface imprinting (5.9 and 11.3 mg g−1) and epitope surface imprinting (46.6 mg g−1) methods. We demonstrated the application in real and synthetic urine samples that the approach allowed the efficient adsorption of HSA in real urine (129.48 mg g−1) is almost double to the binding of HSA in synthetic urine (67.84 mg g−1). Apart from this, only minor interference of Cre (2.74 mg g−1) was observed, eventhough Cre is the final metabolite in urine. These adsorptive submicrosilica materials have potential in the pharmaceutical industry and clinical analysis applications. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 46894.  相似文献   
38.

Scope

The phytosteroid ecdysterone is present in spinach. In this study, the urinary elimination of ecdysterone and its metabolites in humans is investigated following spinach consumption of two different culinary preparations.

Methods and results

Eight participants (four males, four females) ingested 950 (27.1) g sautéed spinach (average [±standard deviation (SD)]) and 912 (70.6) g spinach smoothie as second intervention after washout. Post-administration urines are analyzed by liquid chromatography tandem mass spectrometry (LC-MS/MS). After intake of both preparations, ecdysterone and two metabolites, 14-deoxy-ecdysterone, and 14-deoxy-poststerone, are excreted in urine. The maximum concentration of ecdysterone is ranging from 0.09 to 0.41 µg mL−1 after sautéed spinach and 0.08–0.74 µg mL−1 after smoothie ingestion. The total excreted amount (mean% [±SD]) in the urine as a parent drug plus the metabolites is only 1.4 (1.0) for both sautéed spinach and smoothie. The apparent sex related differences in 14-deoxy-poststerone excretion will need further investigations.

Conclusion

Only a small proportion of ecdysterone from spinach is excreted into urine. No significant differences are found in concentration and recovered amount (%) of ecdysterone, 14-deoxy-ecdysterone, and 14-deoxy-poststerone in urine between sautéed spinach and smoothie ingestion. A discrimination between ecdysterone from food or preparations will be challenging based on urinary concentrations only, at least for later post-administration samples.  相似文献   
39.
NOVAQUATIS是瑞士联邦供水、废水处理及水体保护研究所(EAWAG)的一项综合研究项目,针对目前水污染控制中存在的营养物质及微污染物质处理问题,旨在从多方面探讨将尿液从源头进行分离处理的可能性,以改善目前的废水管理体系。结合目前城市排水工程体系存在的问题及尿液分离技术的优点,介绍了该项目的研究目的,以及7个子项目和1个试点工程的研究内容;最后探讨了该项目的管理模式,并对其存在的主要问题进行了思考。  相似文献   
40.
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