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61.
A new type of low‐molecular‐weight polypyrimidine in a π‐conjugated main chain was prepared by a Grignard reaction between 2‐amino‐4,6‐dichloropyrimidine and 1,4‐dibromo‐2,5‐didodecyloxybenzene in the presence of [1,2‐Bis(diphenylphosphino) ethane]dichloronickel(II). The structure of the copolymer was fully elucidated by Fourier transform infrared spectroscopy, 1H‐NMR, and elemental analysis. The copolymer had good solubility in common organic solvents. The copolymer displayed a bathochromic shift when protonated with an organic or inorganic acid in chloroform or tetrahydrofuran. The copolymer depicted facile p‐doping and good electron‐transporting electrochemical properties in a 1M H2SO4 aqueous solution. The copolymer showed a narrow polydispersity of 1.04. Thermogravimetric analysis showed that the copolymer had a certain thermal stability with no decomposition at a temperature of 250°C under N2. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 41174.  相似文献   
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International Journal on Software Tools for Technology Transfer - A correction to this paper has been published: https://doi.org/10.1007/s10009-021-00629-9  相似文献   
64.
Autism spectrum disorder (ASD) is a multifaced neurodevelopmental disorder that becomes apparent during early childhood development. The complexity of ASD makes clinically diagnosing the condition difficult. Consequently, by identifying the biomarkers associated with ASD severity and combining them with clinical diagnosis, one may better factionalize within the spectrum and devise more targeted therapeutic strategies. Currently, there are no reliable biomarkers that can be used for precise ASD diagnosis. Consequently, our pilot experimental cohort was subdivided into three groups: healthy controls, individuals those that express severe symptoms of ASD, and individuals that exhibit mild symptoms of ASD. Using next-generation sequencing, we were able to identify several circulating non-coding RNAs (cir-ncRNAs) in plasma. To the best of our knowledge, this study is the first to show that miRNAs, piRNAs, snoRNAs, Y-RNAs, tRNAs, and lncRNAs are stably expressed in plasma. Our data identify cir-ncRNAs that are specific to ASD. Furthermore, several of the identified cir-ncRNAs were explicitly associated with either the severe or mild groups. Hence, our findings suggest that cir-ncRNAs have the potential to be utilized as objective diagnostic biomarkers and clinical targets.  相似文献   
65.
黄花软紫草多糖的提取及清除自由基的研究   总被引:2,自引:0,他引:2  
研究了黄花软紫草水溶性多糖的提取及对Fenton反应产生·OH自由基的清除效果。结果表明,以水为溶剂提取的紫草多糖的得率为2.53%,且此粗多糖清除自由基的能力与其浓度呈线性关系。  相似文献   
66.
The present study reports the use of nanomaterial, e.g. Ag nanoparticles (AgNPs), immobilized activated carbon as an effective solid adsorbent for removal of toxic chromium(VI) from water. Chromium(VI) uptake was found favorable in acidic media at pH ≤ 3. Based on Langmuir model, monolayer adsorption capacities of chromium(VI) found equal 93.5 mg/g. The results fitted well with pseudo second-order and Langmuir models. The mechanism of adsorption was explored using the intra-particle diffusion model and the liquid-film model. Chromatographic separation of chromium(VI) was achieved. The AC-AgNPs was successfully recycled for five successive adsorption–desorption cycles indicating its high reusability.  相似文献   
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Surmounting the inhomogeniety issue of gas sensors and realizing their reproducible ppb‐level gas sensing are highly desirable for widespread deployments of sensors to build networks in applications of industrial safety and indoor/outdoor air quality monitoring. Herein, a strategy is proposed to substantially improve the surface homogeneity of sensing materials and gas sensing performance via chip‐level pyrolysis of as‐grown ZIF‐L (ZIF stands for zeolitic imidazolate framework) films to porous and hierarchical zinc oxide (ZnO) nanosheets. A novel approach to generate adjustable oxygen vacancies is demonstrated, through which the electronic structure of sensing materials can be fine‐tuned. Their presence is thoroughly verified by various techniques. The sensing results demonstrate that the resultant oxygen vacancy‐abundant ZnO nanosheets exhibit significantly enhanced sensitivity and shortened response time toward ppb‐level carbon monoxide (CO) and volatile organic compounds encompassing 1,3‐butadiene, toluene, and tetrachloroethylene, which can be ascribed to several reasons including unpaired electrons, consequent bandgap narrowing, increased specific surface area, and hierarchical micro–mesoporous structures. This facile approach sheds light on the rational design of sensing materials via defect engineering, and can facilitate the mass production, commercialization, and large‐scale deployments of sensors with controllable morphology and superior sensing performance targeted for ultratrace gas detection.  相似文献   
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Heparin‐induced thrombocytopenia (HIT) is an uncommon problem in hemodialysis (HD) patients. There have been a few reports on the use of lepirudin, argatroban, or danaparoid in the management of extracorporeal thrombosis (ECT) during dialysis in these patients, because heparin is contraindicated. Here, we report the first long‐term use of bivalirudin to prevent ECT. Our study was conducted at Fahd Bin Jassim Kidney Center in Doha, Qatar. All patients diagnosed with HIT were included. A bivalirudin treatment protocol was developed with the initial dosage and dosage adjustments based on the value of activated partial thromboplastin time (aPTT), the risk of bleeding, and the recurrence of ECT. Eight patients were positive for HIT AB. Among them, three were excluded: two due to the use of warfarin for atrial fibrillation and one due to a negative repeat HIT AB test with no ECT. Five patients who were positive for HIT AB and experienced recurrent ECT events during dialysis were included. These patients were monitored while on bivalirudin protocol for a mean of 4.6 ± 2 months, during which they received a mean number of HD treatments of 66 ± 24. There were no bleeding events or adverse reactions related to bivalirudin during the study. Here, we report the first long‐term successful use of a bivalirudin protocol to prevent ECT in ambulatory HD patients with HIT. This protocol allowed for a simple dosing initiation with easy adjustment based on weight, aPTT, and recurrence of ECT events. The protocol provided excellent safety.  相似文献   
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