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21.
Study of urinary nucleosides as biological marker in cancer patients analyzed by micellar electrokinetic capillary chromatography 总被引:10,自引:0,他引:10
Thirteen normal and modified nucleosides, primarily degradation products of transfer ribonucleic acid (tRNA), were evaluated as potential tumor markers for cancer patients. Their urinary concentrations were determined by means of micellar electrokinetic capillary chromatography (MEKC) in the urine from 54 healthy adults and 70 cancer patients, then quantitatively expressed as a function of creatinine excretion. It was found that urinary nucleosides for cancer patients were on the average significantly higher than those for healthy controls, however, no significant differences were found between male and female or between different ages. Based on 13 urinary nucleoside concentrations, principal component analysis (PCA) could be used to classify 72% of cancer patients from the healthy controls. The present study shows that the precise measurement of urinary nucleosides by MEKC in combining with PCA technique may provide a clinically useful approach for diagnosis of cancer. 相似文献
22.
BODIPY dyes are privileged fluorophores that are now widely used in highly diverse research fields. An overview of BODIPY dyes and a summarization of the different synthetic methodologies reported for direct C-H functionalization of the BODIPY framework have been provided. 相似文献
23.
Ma B Chen Y Hao H Wu M Wang B Lv H Zhang G 《Colloids and surfaces. B, Biointerfaces》2005,41(2-3):197-201
Under the background of algae removal and growth inhibition by ultrasonic irradiation, the effects of ultrasonic irradiation on removal of Microcystis, the concentration variation of microcystins (MC) produced by Microcystis in Microcystis suspension, and sonochemical degradation of microcystins in water, were studied in the paper. The results showed that ultrasonic irradiation could efficiently inhibit the growth of Microcystis, and ultrasonic irradiation shorter than 5 min would not introduce the increase of microcystins dissolved in Microcystis suspension simultaneity. Also, microcystins dissolved in Microcystis suspension would not increase as ultrasonic power increasing. Further research showed that microcystins were effectively degraded in ultrasonic fields. After 20 min ultrasonic irradiation at 150 kHz and 30 W, the removal rate of microcystins reached 70%. 相似文献
24.
Separation and determination of ephedrine alkaloids and tetramethylpyrazine in Ephedra sinica Stapf by gas chromatography-mass spectrometry 总被引:1,自引:0,他引:1
A simple, sensitive, and reliable method using gas chromatography (GC)-mass spectrometry (MS) is developed for the simultaneous determination of ephedrine alkaloids and 2,3,5,6-tetramethylpyrazine (TMP) in Ephedra sinica Stapf. The sample is extracted with ethyl ether and submitted to GC-MS for identification and quantitation without derivatization. The column used for GC is an HP-5 (30.0 m x 250 microm x 0.25 microm, 5% phenyl methyl siloxane), and the carrier gas is helium. The detection limits for ephedrine, pseudoephedrine, and TMP are 0.4 ng 0.7 ng, and 0.02 ng (signal-to-noise ratio of 3), respectively. The reproducibility of the total procedure is proved to be acceptable (RSD < 2%), and the recoveries are above 93%. 相似文献
25.
Mathematical Notes - The Boros–Moll polynomials $$P_m(a)$$ arise in the evaluation of a quartic integral. In the past few years, there has been some remarkable research on the properties of... 相似文献
26.
We study sums and products in a field. Let F be a field with ch(F) ≠ 2, where ch(F) is the characteristic of F. For any integer k ? 4, we show that any x ∈ F can be written as a1 + … + ak with a1, …, ak ∈ F and a1… ak = 1, and that for any α ∈ F {0} we can write every x ∈ F as a1 … ak with a1, …, ak ∈ F and a1 + … + ak = α. We also prove that for any x ∈ F and k ∈ {2, 3, …} there are a1, …, a2k ∈ F such that a1 + … + a2k = x = a1 … a2k.
相似文献27.
Transition metal-catalyzed carbene transfer reaction is one of the most notable advances for C-C bond formation reactionsduring the past decade,which has been widely employed in the preparation of C3-substituted indoles,Here,we described an efficient exa mple of catalyst-and metal-free aminobo ration of alkynes and C—C bond formation with diazo compounds to produce C3-substituted indoles,Diverse alkynyla nilines and diazo compounds ca n be utilized for this tandem transfo rmation under mild reaction conditions,re sulting in broad functional group co mpatibility.Additionally,this metal-free strategy can be extended to construct substituted benzofurans. 相似文献
28.
29.
Bixing Fang Lina Dong Xingwei Ding YingZi Ren Zhongsheng Lv Kuan Liu Feng Zhang Wei Zhang Jianjian Deng Hongbo Xin Xiaolei Wang 《中国化学快报》2019,30(6):1178-1181
Black fungus aerogel (BFA) exhibited interesting double-faced properties. Weexplored the diverse properties of each side of the black fungus in three aspects:water contact angle measurements, liquid selective absorption capacity and air pollutant adsorption abilities. 相似文献
30.
Xue-Chuan Lv Zhi-Cheng Tan Xiao-Han Gao Zhi-Heng Zhang Li-Ni Yang Jun-Ning Zhao Li-Xian Sun Tao Zhang 《Thermochimica Acta》2006,450(1-2):102-104
A metal-organic complex, which has the potential property of absorbing gases, [LaCu6(μ-OH)3(Gly)6im6](ClO4)6 was synthesized through the self-assembly of La3+, Cu2+, glycine (Gly) and imidazole (Im) in aqueous solution and characterized by IR, element analysis and powder XRD. The molar heat capacity, Cp,m, was measured from T = 80 to 390 K with an automated adiabatic calorimeter. The thermodynamic functions [HT − H298.15] and [ST − S298.15] were derived from the heat capacity data with temperature interval of 5 K. The thermal stability of the complex was investigated by differential scanning calorimetry (DSC). 相似文献