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991.
E. M. Molina-Trinidad C. Arteaga de Murphy H. Jung-Cook 《Journal of Radioanalytical and Nuclear Chemistry》2004,260(3):477-489
Good manufacturing practices specify that a well-type scintillation NaI(Tl) crystal detector has to be validated in order
to detect radioactivity from any radiopharmaceutical used to obtain radiopharmacokinetic parameters. A 5 cm well-type NaI(Tl)
scintillation detector was coupled to a multi-channel analyzer centered at the 140 keV 99mTc peak with a 20% window. The area represents counts per minute (cpm). All the net cpm were decay corrected. The activity
source was 99mTc-glucarate developed as an imaging agent for acute myocardial infarction. Wistar rats were injected in a tail vein with
0.1 ml (3.7 MBq) of 99mTc-glucarate solution and 13 blood samples were taken. The cpm were the input data for the WINNONLN program which calculates
radiopharmacokinetic parameters. The detector's efficiency for 99mTc was 15.03% and the sensitivity 1.12 kBq/ml in plasma. The response was linear between 0.31-14.3 kBq/ml of 99mTc-glucarate. The maximum assay variation coefficient was 2.79 and recovery of 99mTc-glucarate in plasma was 99.8%±0.2%. LOD was 0.31 kBq and LOQ = 1.12 kBq in plasma samples. 99mTc-glucarate follows a two-compartment model of distribution with Vd of 21.74 ml±2.71 ml; a Vdss of 74.36 ml±12.67 ml; t
1/2
a0.74 h±0.19 h; t
1/2
b 18.98 h±4.36 h; AUC = 32.75 mCi/min.ml ± 3.73 mCi/min.ml; MRT = 24.35 h±5.51 h and total clearance 3.05 ml/h±0.35 ml/h. The well-type detector fulfills the quality system requirements
and the radiopharmacokinetic parameters for 99mTc-glucarate in rats are reliable.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
992.
多嵌段聚醚氨酯脲为基质的新型高分子固态离子导体 总被引:2,自引:0,他引:2
本文合成了一系列聚乙二醇型多嵌段聚醚氨酯脲,而且用这类聚醚氨酯甩与高氯酸锂制得了一种新型的高分子固态离子导体复合物。在室温和50℃之间,其电导率比聚环氧乙烷为基质的固体电解质的高一到二个数量级,它还具有优良的综合性能。因此,对于室温薄膜蓄电池来说,这种新型的固体电解质是一类良好的候选材料。 相似文献
993.
The capillary electrochromatographic (CEC) analysis of basic compounds on octadecyl-silica stationary phases (Hypersil ODS and Spherisorb ODS I) was studied. A basic drug (fluvoxamine) and one of its possible impurities were used as test compounds. With an eluent of acetonitrile-phosphate buffer (pH 7.0), the compounds could be baseline-separated; however, broad and tailing peaks were obtained. To minimise detrimental interactions with residual silanol groups, the pH of the mobile phase was lowered to 2.5, but the plate numbers were still quite low (<2.6x10(4) plates/m). Addition of a masking agent (hexylamine or triethylamine) to the mobile phase resulted in much better peak efficiencies (ca. 1x10(5) plates/m). Therefore, the influence of the amine concentration and pH of the mobile phase on the CEC performance (peak width, peak tailing, electroosmotic flow, selectivity) was investigated in detail. Highest efficiencies (2.8x10(5) plates/m) could be obtained with the Spherisorb column, while the Hypersil column offered a better selectivity. Furthermore, the results show that the residual silanol groups are (at least partly) responsible for the separation of the basic compounds and that the amount of injected sample has an unusually large effect on the peak efficiency. The usefulness of the system for impurity profiling was demonstrated with a mixture containing fluvoxamine and its stereoisomer (a possible impurity) at the 0.1% level. The general effectiveness of amine additives in CEC was illustrated by the separation of a mixture of five structurally different basic drugs yielding plate numbers in the 1x10(5)-3x10(5) plates/m range. Comparison with capillary electrophoretic analysis revealed a unique selectivity of the CEC system which is based on both electrophoretic mobility and chromatographic partitioning. 相似文献
994.
The influence of monosubstitution at phonyl rings in a series of T(x-P) PMn (Ⅲ)Cl (x = o , m , p-CH3, CH3O, Cl, Br, I, NO , o-NH2, p-(CH3)3C) on the biomimetic catalytic hydroxylation and chlorizaiton of cyclohexane with PhIO was studied. The yields of cyclohexanol and chlorocyclohexane increased with the electron-withdrawing ability of the substituent in this manganese complex. The fair linear correlations between the yields of cyclohexanol and para or ortho substituent constant are presented as:logYx/YH = 0.310p+0.03, logyx/YCH3 = 0.61σ0.07Es+0.05, But there are no linear correlations between the yields of chloro-cyclohexane and either para, ortho or meta substituent constants. 相似文献
995.
Genetic aspects of variation of protein amounts in maize and pea 总被引:2,自引:0,他引:2
Using high-resolution two-dimensional polyacrylamide gel electrophoresis we studied the polymorphism of protein amounts in some genotypes of maize and pea. This type of variability seems to be rather common and insensitive to environmental conditions, as attested by the comparison of the patterns of two maize lines harvested in two different years. A large-scale experiment involving 5 lines, 7 of their hybrids, and 6 organs (or physiological stages) of maize allowed us to examine numerous polypeptides regarding their genetic variability, their amount differences between organs and the inheritance of their abundance. Genetic and organ variations are not independent: polypeptides whose amount varies from one organ to another are, for the most part, genetically variable (59%), while the stable polypeptides are not often genetically variable (18%). We found a striking organ specificity for (i) the extent of quantitative variability (from 2.3-15.4% of the polypeptides), (ii) the occurrence and the type of variation for a given polypeptide (an intensity difference seen in an organ can disappear or even be reversed in another one), (iii) the kind of inheritance (additive/non-additive): combining the 6 organs and the 7 hybrids we found 101 cases of non-additivity (4% of the total) which concern as many as 72 different spots, that is to say that in most cases a polypeptide displaying nonadditivity in an organ seems to display additivity in the other ones. Moreover, for most of the polypeptides with nonadditive inheritance the hybrid spot presents an intensity similar to that of the most intense parental spot.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
996.
The synthesis and properties of di-2-pyridyl ketone 2-furoylhydrazone as an analytical reagent are described. A rapid procedure for the fluorimetric determination of aluminium at the 10-100 ng ml level, at pH 6.1-6.5 (lambda(exc) 395 nm, lambda(em) 465 nm) has been established. Interferences have been evaluated, and the procedure has been applied satisfactorily to determination of aluminium in sea-water. 相似文献
997.
The first examples of intramolecular Zr-catalyzed electrophilic alkylation of aryl olefins are disclosed. Substituted carbo- and heterocycles are prepared efficiently and diastereoselectively. 相似文献
998.
Zuev V. V. de Vekki D. A. Kuchaev A. E. Vorob’ev M. V. Skvortsov N. K. 《Russian Journal of General Chemistry》2004,74(11):1679-1685
Hydrosilylation of p-substituted acetophenones XC6H4COCH3 (X = H, Me, MeO, HO, F, Cl, NO2) with 1,1,3,3-tetramethyldisiloxane in the presence of rhodium and platinum complexes was studied. The Pt(II) complexes are less active but more selective catalysts of hydrosilylation of acetophenones. Six new 1-(1-arylethoxy)-1,1,3,3-tetramethyldisiloxanes were prepared.Translated from Zhurnal Obshchei Khimii, Vol. 74, No. 11, 2004, pp. 1804–1811.Original Russian Text Copyright © 2004 by Zuev, de Vekki, Kuchaev, Vorobev, Skvortsov.This revised version was published online in April 2005 with a corrected cover date. 相似文献
999.
表面修饰二氧化锡纳米微晶的制备与表征 总被引:10,自引:0,他引:10
制备了硅烷偶联剂KH-570表面修饰的SnO2纳米微晶,通过FT-IR、XPS、TEM和TG-DTA对其结构和表面特性进行表征和研究. FT-IR和XPS分析结果确证了KH-570与SnO2表面是以化学键合或物理吸附方式相结合,粒子表面存在酯基等有机官能团的红外吸收特征;观测到KH-570中Si原子的Si2s和Si2p谱线. TEM分析表明,表面修饰反应增强了SnO2纳米微晶的疏水性和分散性.由XPS和TG的实测数据探讨了纳米粒子具有较低包覆量的可能原因. 相似文献
1000.
Christophe Hoarau Alexis Du Fou de Kerdaniel Pierre Grandclaudon Francis Marsais 《Tetrahedron letters》2005,46(49):8573-8577
The efficient and regioselective palladium-catalyzed C-2 arylation of ethyl 4-oxazolecarboxylate 1 with phenyliodide is described. The different parameters (solvent, base, ligand and catalyst) for the optimal conditions of this arylation process have been screened. 相似文献