紫外分光光度法快速测定消毒剂中三氯生含量

为建立紫外分光光度法测定消毒剂和抗菌剂中三氯生的方法,采用紫外分光光度计,在280 nm波长下,对用无水乙醇稀释后的三氯生样品直接测定,进行了工作曲线、精密度、回收率等实验。结果,当标准溶液在0.0～50.0 μg/ml浓度范围内,回收率90％～105％,相对标准偏差1.5％,与高效液相色谱法对比,结果无显著性差异,并与配方值相符。经过对54℃ 14 d和37℃ 90 d保存样检测,标准和样品含量均没有降低。结果显示,三氯生具有良好稳定性,紫外分光光度法测定三氯生含量,方法简便、快速、准确、灵敏度高,适宜大批样品测定。     

Color Aspect of Monolithic Zirconia Restorations: A Review of the Literature

Monolithic zirconia restoration is an acceptable treatment option in restorative dentistry and a developing trend in esthetic dentistry. Digital dentistry has simplified fabrication of monolithic zirconia restorations. Zirconia ceramic has introduced an opportunity to achieve both esthetic and mechanical requirements for restorations. This is rarely found for a ceramic in dentistry. Monolithic zirconia restorations represent an acceptable durability, comparable to metal‐ceramic restorations, while they are superior to metal‐ceramic restorations esthetically; however, difficulties to gain an optimal shade reproduction and a color match with monolithic zirconia restorations still remain. The color of these restorations may be influenced by manufacturing processes, laboratory procedures, and clinical factors. Manufacturing processes determine basic optical properties of zirconia ceramics. Different laboratory procedures may create optical changes in zirconia ceramics. Also clinical factors such as dental background, cement, and zirconia restoration features may affect the resulting color. This literature review aimed to discuss potent factors in the color of monolithic zirconia restorations. An electronic search of the PubMed/Google Scholar database was performed to find related English‐language articles published between January 1, 2000, and October 31, 2017. The key terms of background, cement, ceramic, color, esthetics, shade, spectrophotometry, thickness, translucency, and zirconia were used both individually and simultaneously. Also, a manual search was conducted, and five classic articles of color science were added. Thus 192 articles were included. In the last decade, shade reproduction of monolithic zirconia restorations has been highly regarded; however, further improvements are required in the manufacturing process to produce tooth‐like zirconia ceramics. An esthetic guideline named background‐cement‐ceramic color harmony was suggested in this study; however, more clinical practice guidelines should be established for monolithic zirconia restorations on esthetics, and therefore, more studies are required.     

《中国药典》2015年版中纯化水硝酸盐检查商榷

目的：对《中国药典》2015年版二部纯化水中硝酸盐的检查方法提出意见建议。方法：按照标准考察了试剂“硫酸”对硝酸盐检查结果的影响,并首次建立了紫外-可见分光光度法作为硝酸盐检查的方法。结果：试剂“硫酸”的质量对硝酸盐比色法的检查影响很大,可采用紫外-可见分光光度法进一步测定。结论：紫外-可见分光光度法可作为《中国药典》纯化水中硝酸盐检查方法的重要补充。     

流动注射仪法测定水中氰化物的效果评价

目的 对流动注射分析仪法(FIA)测定水中氰化物的方法进行评价。 方法 采用北京吉天FIA-6000+流动注射仪法与异烟酸-巴比妥酸分光光度法分别测定水中氰化物,并对比实验结果。 结果 实验表明,在0~200 μg/L浓度范围内,FIA法具有很好的线性关系,检出限低,准确度好,精密度高,回收率满意。 结论 FIA法符合实验分析要求,与异烟酸-巴比妥酸分光光度法比较具有简便快速、准确稳定、灵敏度高等优势,在生活饮用水以及水源水中氰化物的测定上具有可行性。     

Coloration of Silicone Prostheses: Technology versus Clinical Perception. Is There a Difference? Part 2, Clinical Evaluation of a Pilot Study

Purpose: The aim of this investigation was to explore the relationship between an objective computer measurement of color difference (ΔE) and subjective clinical opinion of a “good” color match between silicone samples and skin. Materials and Methods: In Part 1 of this study, silicone samples were colored to match the skin of 19 African‐Canadian subjects based on spectrophotometric measurements and pigment formulae determined by computerized color formulation software. Four iterative samples were prepared for each subject; a ΔE value was recorded for each sample to represent the color difference between the silicone sample and skin. In this article, Part 2, five judges independently assessed the color match of the silicone samples to the skin of each of the subjects. Skin and silicone samples were rated on a five‐point scale as a measure of “color match.” A multivariate analysis was used to determine relationships between judges’ assessments and the following variables: color difference between silicone and skin (ΔE), pigment loading, and skin characteristics (L*, a*, b*). Results: There was a positive correlation between judges’ scores and low ΔE values for the first two samples. All judges rated the first sample a poorer color match than the fourth sample (p < 0.015). The third sample performed better overall according to judges. Increased pigment loading in the fourth sample resulted in poorer scores. A trend was observed in pigment selection based on skin values, though no significant relationships were determined. Conclusion: Spectrophotometry and computerized color formulation technology offer an enhanced understanding of color for its artistic application in facial prosthetic treatment. While some correlation between the objective and subjective assessments of color match exist, it is not a simple relationship. Further study is required to better understand the relationship between technology and clinical perception, specifically in objective and subjective assessments of a “good” color match of silicone to skin.     

砷铈催化分光光度法测定尿碘的实验室内质量控制

目的建立砷铈催化分光光度法测定尿中碘的实验室内质量控制体系。方法通过试验确定砷铈催化分光光度法测定尿中碘方法的精密度、准确度和检出限,绘制碘测定的均数质量控制图。结果该方法的标准曲线范围碘质量浓度为0～300μg/L,标准曲线的相关系数｜r｜=0．9998,检出限3μg／L,加标回收率为92．4％～106．2％,相对标准偏差0．65％～1．43％。结论实验室内质量控制体系的建立,保证了砷铈催化分光光度法测定尿中碘的结果准确可靠。     

催化褪色光度法测定中草药白花蛇舌草中的微量锗

目的：利用催化褪色光度法测定中草药白花蛇舌草中微量元素锗。方法用超声波清洗仪提取中草药白花蛇舌草中微量元素锗,并用催化褪色光度法测定锗元素的含量。研究痕量锗在稀硫酸介质中催化加速溴酸钾、过氧化氢与中性红之间的反应,建立催化光度法测定痕量锗的方法。结果本实验测得中草药白花蛇舌草中无机锗（Ⅳ）含量为0.0248μg/g。结论该法灵敏度、精密度均能满足检测工作的需要。     

野蔷薇不同部位总黄酮含量比较研究

目的:比较野蔷薇不同部位总黄酮含量,为今后开发利用野蔷薇提供依据。方法:采用超声提取法提取野蔷薇不同部位总黄酮,以芦丁为对照品,采用分光光度法测定的总黄酮含量为指标,对野蔷薇不同部位总黄酮含量进行比较。结果:通过比较野蔷薇叶、青果皮、青果籽、红果皮、红果籽、茎、根皮总黄酮含量得出:根皮(137.2 mg·g-1)叶(43.22 mg·g-1)茎(36.05 mg·g-1)青果皮29.94 mg·g-1)红果皮(15.25 mg·g-1)红果籽(4.761 mg·g-1)青果籽(4.396 mg·g-1)。结论:野蔷薇中总黄酮含量丰富,尤其根皮中含量最高,潜在应用价值大。     

Spectrophotometric determination of leukocytes in urine

A spectrophotometric method based on myeloperoxidase activity for the determination of leukocytes in urine is described. Red cells that may be found in urine samples were lysed by an ammonium chloride method. Leukocytes were then sedimented by centrifugation and lysed using Triton X-100 (Sigma Chemicals Co., St. Louis, MO). Myeloperoxidase-catalyzed oxidation of o-dianisidine was carried out at 37 degrees C, pH 7. The reaction was stopped with the addition of 2 M H2SO4, and a stable form of oxidized o-dianisidine in acidic solution was obtained. Solid particles that may be found in urine samples were removed by centrifugation to avoid turbidity, and absorbance values of the supernatants were recorded at 400 nm. An Average number of leukocytes were noted per number of fields by microscopic examination and were related with the absorbance values of the supernatants at 400 nm. Pearson correlation (r) between our presented spectrophotometric analysis results and visual microscopic analysis was 0.877. Roche Combur 10-test M strips (Roche, Mannheim, Germany) and Multistix 10 SG Bayer test strips (Bayer Diagnostics, UK) were 0.645 and 0.648, respectively (P < 0.0001).