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201.
微量元素制剂辅助治疗复发性口疮疗效观察 总被引:1,自引:0,他引:1
报道了103例RAU患者使用微量元素制剂辅助治疗的临床疗效观察。将两个实验组分别与对照组比较。结果显示:应用锌、铁制剂辅助雷公藤、复方丹参等治疗的实验组I效果优于雷公藤、复方丹参对照组(P〈0.01),而仅用锌、铁制剂治疗的实验组Ⅱ临床效果比对照组差(P〈0.01),但锌、铁制剂有改善RAU临床症状作用,而不能较好地控制其复发。 相似文献
202.
病毒性心肌炎与微量元素关系的探讨 总被引:1,自引:0,他引:1
应用日本岛津ICPQ-1012型高频等离子体发射光谱仪测定了病毒性心肌炎组47例和正常儿童组60例全血中14种元素的水平,结果表明,心肌炎组血锌、铁、铜、钴、钛、铬、镍、铅、钛、镉的含量低于正常组,两者间有显著和非常显著性差异(P〈0.05,P〈0.01),血钼、锶则高于正常组,且有显著性差异(P〈0.05),血锰、镁、钙与正常组无差异(P〉0.05),提示病毒性心肌炎的患儿存在着血锌、铁、铜、钴 相似文献
203.
TheBeckInannrearrangement,theacid-mediatedisomerizationofoximestoamides,wasfirstdiscoveredinl886l.Asoneoftheoldestandmostfamiliartransformationsinorganicchemistry,ithasbeenwidelystudiedandagreatvarietyofmethodstoconductthistfansformationhavebeenreported'.However,mostofthesemethodswerecarriedoutbyusingalargeamountofsolventswithlongreactiontime.Whatismore,thepriorpreparationofthecorrespondingketoximesisusuallyrequired,whichmakestheseprocessesinconvenientandlessattractive.Bytakingadvantageofboth… 相似文献
204.
Biosorption of copper(II) and zinc(II) from aqueous solution by Pseudomonas putida CZ1 总被引:1,自引:0,他引:1
Chen XC Wang YP Lin Q Shi JY Wu WX Chen YX 《Colloids and surfaces. B, Biointerfaces》2005,46(2):101-107
To study Pseudomonas putida CZ1, having high tolerance to copper and zinc on the removal of toxic metals from aqueous solutions, the biosorption of Cu(II) and Zn(II) by living and nonliving P. putida CZ1 were studied as functions of reaction time, initial pH of the solution and metal concentration. It was found that the optimum pH for Zn(II) removal by living and nonliving cells was 5.0, while it was 5.0 and 4.5, respectively, for Cu(II) removal. At the optimal conditions, metal ion biosorption was increased as the initial metal concentration increased. The adsorption data with respect to both metals provide an excellent fit to the Langmuir isotherm. The binding capacity of living cells is significantly higher than that of nonliving cells at tested conditions. It demonstrated that about 40-50% of the metals were actively taken up by P. putida CZ1, with the remainder being passively bound to the bacterium. Moreover, desorption efficiency of Cu(II) and Zn(II) by living cells was 72.5 and 45.6% under 0.1M HCl and it was 95.3 and 83.8% by nonliving cells, respectively. It may be due to Cu(II) and Zn(II) uptake by the living cells enhanced by intracellular accumulation. 相似文献
205.
Sakamoto M Cai X Hara M Fujitsuka M Majima T 《The journal of physical chemistry. A》2005,109(11):2452-2458
The properties and reactivities of the xanthone (Xn) ketyl radical (XnH*) in the doublet excited state (XnH*(D1)) were examined by using two-color two-laser flash photolysis. The absorption and fluorescence of XnH*(D1) were observed for the first time. Several factors governing the deactivation processes of XnH*(D1) such as interaction and reaction with solvent molecules were discussed. The remarkable change of reactivity of XnH*(D1) compared with that in the ground state (XnH*(D0)) was indicated from the experimental results. The rapid halogen abstraction of XnH*(D1) from some halogen donors such as carbon tetrachloride (CCl4) was found to occur. The halogen abstraction occurred more efficiently in the polar solvents than in the nonpolar solvents. It is suggested that the polar solvents promote the spin distribution of XnH*(D1) of the phenyl ring favorable to the halogen abstraction. 相似文献
206.
Yan YG Li QX Huo SJ Ma M Cai WB Osawa M 《The journal of physical chemistry. B》2005,109(16):7900-7906
A versatile two-step wet process to fabricate Pt, Pd, Rh, and Ru nanoparticle films (simplified as nanofilms hereafter) for in situ attenuated total reflection Fourier transform infrared (ATR-FTIR) study of electrochemical interfaces is presented, which incorporates an initial chemical deposition of a gold nanofilm on the basal plane of a silicon prism with the subsequent electrodepostion of desired platinum group metal overlayers. Galvanostatic electrodeposition of Pt, Rh, and Pd from phosphate or perchloric acid electrolytes, or potentiostatic electrodeposition of Ru from a sulfuric acid electrolyte, yields sufficiently "pinhole-free" overlayers as evidenced by electrochemical and spectroscopic characterizations. The Pt group metal nanofilms thus obtained exhibit strongly enhanced IR absorption. In contrast to the corresponding metal films electrochemically deposited directly on glassy carbon and bulk metal electrodes, the observed enhanced absorption for the probe molecule CO exhibits normal unipolar band shapes. Scanning tunneling microscopic (STM) images reveal that fine nanoparticles of Pt group metals are deposited around wavy and stepped bunches of Au nanoparticles of relatively large sizes. This ubiquitous strategy is expected to open a wide avenue for extending ATR surface-enhanced IR absorption spectroscopy to explore molecular adsorption and reactions on technologically important transition metals, as exemplified by successful real-time spectroscopic and electrochemical monitoring of the oxidation of CO at Pd and that of methanol at Pt nanofilm electrodes. The spectral features of free water molecules coadsorbed with CO on Pt, Pd, Rh, and Ru are also discussed. 相似文献
207.
Cai X Sakamoto M Fujitsuka M Majima T 《Chemistry (Weinheim an der Bergstrasse, Germany)》2005,11(22):6471-6477
The lifetimes of benzophenone in the higher triplet excited state (BP(T(n))) and several BP derivatives in the T(n) states were measured directly to be tau(T(n))=37+/-7 ps and 20-33 ps, respectively, by using the nanosecond-picosecond (ns-ps) two-color/two-laser flash photolysis method. Based on the direct measurements of tau(T(n)) of BP(T(n)), the triplet energy transfer (TET) from BP(T(n)) to quenchers (Q), such as carbon tetrachloride (CCl4), benzene (Bz), and p-dichlorbenzene (DCB), was investigated. The fast TET from BP(T(n)) to Q can be attributed to the lifetime-dependent quenching process, according to the Ware theoretical model of the bimolecular energy transfer reaction. The contribution of the lifetime-dependent term on k(TET) was 27, 60, and 86% for CCl4, Bz, and DCB as the Q of BP(T(n)), respectively, indicating that the TET from BP(T(n)) to Q is influenced not only by tau(T(n)), but also by the size of Q. 相似文献
208.
Determination of several sugars in serum by high-performance anion-exchange chromatography with pulsed amperometric detection 总被引:1,自引:0,他引:1
In this paper, a sensitive, simple and direct method for simultaneous determination of glucose, ribose, isomaltose and maltose in serum sample by high-performance anion-exchange chromatography coupled with integrated pulsed amperometric detection was developed. The four target analytes were easily and completely separated on an anion-exchange column at a flow-rate of 0.25 mL/min by binary step gradient elution in about 16 min and the two eluents were deionized water and 500 mM sodium hydroxide, respectively. The separated four analytes were detected directly by using a gold electrode and quadruple-potential waveform integrated pulsed amperometry without derivatization. Under the optimized conditions, when the injection volume was 25 microL, the detection limits (signal-to-noise ratio equal to 3) for glucose, ribose, isomaltose and maltose were 0.92, 7.50, 12.9 and 10.3 ng/mL, respectively. The calibration graphs of peak area for the four analytes were linear over two to three orders of magnitude with correlation coefficients greater than 0.998. R.S.D. of peak areas of the four analytes for five determinations were no more than 5.6%. The analytical method had been applied to the determination of glucose, ribose, isomaltose and maltose in real serum samples and good results with low relative standard deviation not more than 5.3% were obtained. The accuracy of the proposed method was tested by recovery measurements on spiked samples and good recovery results (98.1-107.9%) were obtained. 相似文献
209.
Shou‐Ri Sheng Xiao‐Ling Liu Yong‐Fen Tong Lie Chen Hong‐Li Wen Cai‐Sheng Song 《中国化学会会志》2005,52(5):943-946
Several new methyl substituted poly(aryl ether ketone)s containing sulfone linkage with inherent viscosities of 0.62–0.84 dL/g have been prepared from 4,4′‐bis(2‐methylphenoxy)diphenylsulfone and 4,4′‐bis(3‐methylphenoxy)diphenylsulfone with terephthaloyl chloride and isophthaloyl chloride by electrophilic Friedel‐Crafts acylation in the presence of DMF with anhydrous AlCl3 as a catalyst in 1,2‐dichloroethane, respectively. These polymers having weight‐average molecular weight in the range of 71,000–49,000 are all amorphous and show high glass transition temperatures ranging from 167 °C to 191 °C, excellent thermal stability at temperatures over 400 °C in air or nitrogen, high char yields of 51–58% in nitrogen and good solubility in CHCl3 and polar solvents such as DMF, DMSO and NMP at room temperature. 相似文献
210.
The pollution characteristics of ambient fine particulate matter(PM2.5) containing polycyclic aromatic hydrocarbons(PAHs) and nitrated PAHs(NPAHs) in samples collected during a typical winter time period in Taiyuan of China were investigated.The obtained results revealed that the mean mass concentrations of PM2.5,SPAHs(sum of 16 PAHs) and SNPAHs(sum of 3 NPAHs) on PM2.5were161.4 mg/m3,119.8 ng/m3and 0.446 ng/m3,respectively.Diagnostic ratios of PAHs and NPAHs implied that coal consumption might be the main source of the PM2.5pollution.The measured PM2.5mass concentrations,BaP equivalent toxicity(28.632 ng/m3) and individual carcinogenicity index(3.14 10 5) were much higher than those of the recommended safety standards. 相似文献