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971.
972.
采用火焰原子吸收分光光度法测定了心宝丸中钠,钾,钙,镁,铁,铬,锰,镍,镉,铜,锌11种微,宏量元素的含量。结果表明,心宝丸中含有丰富的微量,宏量元素。为探讨中成药中微量,宏量元素与治疗冠心病的关系提供了有用的数据。 相似文献
973.
制备不同形貌羟基磷灰石纳米颗粒,检测其对骨肉瘤细胞生长的影响.采用化学沉淀的方法,可控制备球形和杆状纳米羟基磷灰石,并通过透射电子显微镜(TEM)、原子力学显微镜、傅立叶变换红外光谱仪(FT-IR)和X-射线衍射仪(XRD)对所制备的颗粒进行表征.通过光镜和投射电子显微镜分析不同形貌羟基磷灰石颗粒对骨肉瘤细胞增殖和形貌的影响.结果表明,球形纳米羟基磷灰石对骨肉瘤细胞的抑制作用更明显. 相似文献
974.
The large and growing number of patients undergoing nuclear medicine procedures and workers involved in this practice requires continued efforts to improve the quality of diagnosis and to reduce the radiological risk associated. In Brazil, external individual monitoring with a dosemeter located on the thorax is compulsory for all workers in controlled areas. Extremity dosemeters are recommended in activities where hand dose can be much higher than on the thorax. This is typically the case for nuclear medicine procedures, but extremity dosemeters are not regularly used in Brazil. With the aim to study the occupational dose distribution in the nuclear medicine staff during their tasks of preparation and injection of radionuclides, Harshaw TLD chips of LiF:Mg,Cu,P (TLD-100H) were used for individual monitoring on different parts of the worker body. As expected, all doses measured on the thorax were much lower than on the hands. For both Single Photon Emission Computed Tomography (SPECT) and Positron Emission Tomography (PET), the dose to the fingers during preparation is about two orders of magnitude higher than in the thorax, and in the injection procedure, one order higher. The doses received by the workers' fingers varied widely depending on how they hold the syringe, but fingertips always received higher doses. The dose values measured in the eye lens were 200% higher than the one measured on the thorax. 相似文献
975.
《应用有机金属化学》2017,31(11)
Various nitrogen‐doped titania particles were prepared and, for visible light sensitizing, the biological pigment hematoporphyrin was grafted onto their surfaces. The nanohybrid products were characterized using X‐ray diffraction, Fourier transform infrared and ultraviolet–visible spectroscopies and Brunauer–Emmett–Teller surface area analysis. A high‐performance visible light helical flow photoreactor was designed and used for the photocatalytic degradation of methyl orange (MO) over these photocatalyst products. Accordingly, response surface methodology was employed for design of experiments and optimization. The influencing parameters were initial N/Ti molar ratio, dosage of nanohybrids and solution pH. These parameters were statistically significant and a quadratic correlation was developed for degradation efficiency (DE) variations. A maximum DE of 89.2% was attainable, after 60 min treatment, under the optimum conditions of initial N/Ti molar ratio of 4.93 (ca 5), nanohybrid dosage of 0.73 g l−1 and pH of 4.8. The MO degradation kinetics over the catalyst surface followed the modified Langmuir–Hinshelwood model. The important role of hydroxyl radicals was confirmed using mannitol scavenger. Performing the photocatalytic reaction with the developed set‐up showed excellent efficiency and energy consumption in comparison with similar processes. 相似文献
976.
New series of (2S,3R,4S,6R)-3-methyl-4-alkyl-2,6-diarylpiperidin-4-ol were synthesised by the reduction of cis-3-alkyl-2,6-diarylpiperidin-4-one using Grignard reagent. The structural assignments and conformational studies of the synthesised compounds were established based on the IR, 1H NMR, 13C NMR, NOESY and mass spectral studies. Their stereochemical effect on antibacterial, antifungal and anthelmintic activities was studied. 相似文献
977.
《Biomedical chromatography : BMC》2017,31(5)
In the present study, we aimed to develop a method for thymol sulfate and thymol glucuronide determination in plasma, liver and duodenal wall of broiler chickens after feeding with a Thymus vulgaris essential oil at the different concentrations (0.01, 0.05 and 0.1% w /w). UHPLC coupled with accurate‐mass QTOF‐MS was used for identification and quantification of thymol metabolites. Novel Waters Oasis Prime HLB solid‐phase extraction cartridges were applied to sample clean‐up with extraction recoveries ranged from 85 to 92%. The presence of thymol glucuronide was confirmed by MS software according to molecular formula, score, mass error and double bond equivalent. In terms of validation, calibration curves of thymol sulfate were constructed in matrix samples with linearity from 3.91 to 250.0 ng/mL and correlation coefficients were within the range of 0.9979–0.9995. Limits of detection were 0.97, 0.29 and 0.63 ng/mL and limits of quantification were 3.23, 0.97 and 2.09 ng/mL for plasma, liver and duodenal wall, respectively. Intra‐day and inter‐day precision expressed as relative standard deviation were <4.35%. To highlight, thymol metabolites were directly detected for the first time in liver and duodenal wall and this method was shown to be successfully applicable for investigation of thymol metabolism in chickens after thyme essential oil ingestion. 相似文献
978.
Mingfeng Yu Ngee H Lim Samantha Ellis Hideaki Nagase James A Triccas Peter J Rutledge Matthew H Todd 《ChemistryOpen》2013,2(3):99-105
The synthesis and matrix metalloproteinase (MMP) inhibitory activity of a cyclam–marimastat conjugate and its metal complexes are described. The conjugate, synthesized with a copper(I)-catalyzed Huisgen 1,3-dipolar cycloaddition (“click” reaction), contains two zinc-binding groups (ZBGs). The metal complexation behavior with copper(II) and zinc(II) was investigated using UV/Vis spectrophotometry and 1H NMR spectroscopy, respectively, demonstrating that the first equivalent of the metal ion was chelated by the cyclam-triazole moiety rather than the hydroxamic acid site. Thus, the corresponding mononuclear metal–cyclam complexes were successfully prepared with one equivalent of the metal salt. Both the cyclam–marimastat conjugate and its metal complexes exhibited slightly reduced potency against MMP-1, but essentially identical inhibitory activity against MMP-3. The conjugate and its metal complexes displayed little or no cytotoxicity, further supporting their potential suitability for imaging MMP localization and activity. To the best of our knowledge, this is the first report that describes the incorporation of metal complexes into an MMP inhibitor without influencing the preexisting ZBG, and the first report of the evaluation of structures containing more than one ZBG as MMP inhibitors. 相似文献
979.
Maryam Ezoddin Laleh Adlnasab Akram Afshari Kaveh Mohammad Ali Karimi Behnaz Mahjoob 《Biomedical chromatography : BMC》2019,33(9)
A simple method, air‐assisted dispersive micro‐solid‐phase extraction‐based supramolecular solvent was developed for the preconcentration of tramadol in biological samples prior to gas chromatography–flame ionization detection. A new type of carrier liquid, supramolecular solvent based on a mixture of 1‐dodecanol and tetrahydrofuran was combined with layered double hydroxide coated on a magnetic nanoparticle (Fe3O4@SiO2@Cu–Fe–LDH). The supramolecular solvent was injected into the solution containing Fe3O4@SiO2@Cu–Fe–LDH in order to provide high stability and dispersion of the sorbent without any stabilizer agent. Air assisted was applied to enhance the dispersion of the sorbent and solvent. A number of analytical techniques such as Fourier transform‐infrared spectrometry, field emission scanning electron microscope, energy‐dispersive X‐ray spectroscopy and X‐ray diffraction measurements were applied to assess the surface chemical characteristics of Fe3O4@SiO2@Cu–Fe–LDH nanoparticles. The effects of important parameters on the extraction recovery were also investigated. Under optimized conditions, the limits of detection and quantification were obtained in the range of 0.9–2.4 and 2.7–7.5 μg L?1 with preconcentration factors in the range of 450–472 in biological samples. This method was used for the determination of tramadol in biological samples (plasma, urine and saliva samples) with good recoveries. 相似文献
980.
《Angewandte Chemie (International ed. in English)》2017,56(12):3142-3160
The important role of vesicles in many aspects of cell function is well‐recognized, but only recently have sophisticated imaging techniques begun to reveal their ubiquity in nature. While we further our understanding of the biological properties of vesicles and their physiological functions, increasingly elegant artificial vesicles are being developed for a wide range of technological applications and basic research. Herein, we examine the state of the art of biological and synthetic vesicles and place their biological features in the context of recent synthetic developments, thus providing a unique overview of these complex and rapidly developing fields. The challenges and opportunities associated with future biological and synthetic studies of vesicles are also presented. 相似文献