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751.
A simple and efficient method was developed for the chemical fingerprint analysis and simultaneous determination of four phenylnaphthalene‐type lignans in Vitex negundo seeds using high‐performance liquid chromatography with diode array detection. For fingerprint analysis, 13 V. negundo seed samples were collected from different regions in China, and the fingerprint chromatograms were matched by the computer‐aided Similarity Evaluation System for Chromatographic Fingerprint of TCM (Version 2004A). A total of 21 common peaks found in all the chromatograms were used for evaluating the similarity between these samples. Additionally, simultaneous quantification of four major bioactive ingredients was conducted to assess the quality of V. negundo seeds. Our results indicated that the contents of four lignans in V. negundo seeds varied remarkably in herbal samples collected from different regions. Moreover, the hierarchical clustering analysis grouped these 13 samples into three categories, which was consistent with the chemotypes of those chromatograms. The method developed in this study provides a substantial foundation for the establishment of reasonable quality control standards for V. negundo seeds.  相似文献   
752.
ABSTRACT

In this study, aluminum doped zinc oxide thin films were deposited on ordinary glass substrates at the temperature of 425°C by spray pyrolysis technique for various doping concentrations of aluminum ranging from 1 to 5 at.%. The effect of dopant concentration on structural, morphological and optical properties of ZnO:Al thin films was studied. Optical band gap of the films increased with doping percentage and started to decrease from 2 at.% of dopant. The average transmittance for 2at.% ZnO:Al film is significantly increased over 90% in the visible region at 450 nm which is crucial for optoelectronic applications.  相似文献   
753.
OBJECTIVES: This study was conducted to determine the frequency of CYP2C9 alleles in Omani patients receiving warfarin and to correlate genotyping data with warfarin dosage. The Omani population has Asian and African ethnicities. METHODS: CYP2C9 genotypes were determined by the polymerase chain reaction restriction fragment length polymorphism method. Non-parametric Kruskal-Wallis test was used to compare groups of continuous data for significance differences. RESULTS: Genotyping data showed that 12.7 and 5.8% of the samples were heterozygous for the CYP2C9*2 and CYP2C9*3 alleles, respectively. The CYP2C9*2 allele frequency was 0.074 in our population. It was 0.029 for CYP2C9*3. CONCLUSION: This is the first report on the presence of CYP2C9*2 allele homozygocity in any Asian or African population.  相似文献   
754.
Fructus Xanthii (Cang-Er-Zi) is a traditional Chinese medicine that is used in curing nasal diseases and headache according to the Chinese Pharmacopoeia. For the effective quality control of its medicinal values, reflected by chemical variation patterns, in addition to the relationship with genetic diversity, analyses based on UV spectrophotometry, HPLC fingerprinting and inter-simple sequence repeat (ISSR) molecular markers were carried out, involving 16 Xanthium populations from different locations in China. The HPLC data showed considerable variation of chemical constituents among the 16 Xanthium populations, and they were classified to three chemotypes by hierarchical clustering analysis. Abundant genetic diversity was detected among the Xanthium populations, which were also clustered into three groups based on their ISSR data and varied according to different species. Combining the genetic divergence and chemical differences showed an important result that, in the two chemotypes, the higher contents of total phenolic acids (TPA) in Fructus Xanthii showed greater genetic diversity (I). We suggest that genetic diversity affects the contents of TPA. Since variable phenolic acid contents may affect therapeutic efficacy, it is important to point out that combining the use of genetic base with chemotype will help control the favourable chemotypes and breed new cultivars with more desirable chemical constituents.  相似文献   
755.
A series of group 12 elements for Zn(II), Cd(II), Hg(II) complexes of glibenclamide were synthesized and characterized using various spectroscopic techniques and magnetic moments. The complexes exhibited significant activity against gram-negative and gram-positive bacteria species. Zn(II) complex showed remarkable hypoglycemic activity whereas Cd(II) and Hg(II) complexes exhibited antibacterial activity.  相似文献   
756.
Phenyl- and ethyl-magnesium bromides undergo regioselective asymmetric allylic substitution with high enantioselectivity under the catalysis of chiral amidophosphane-copper(I) complexes.  相似文献   
757.
The homo-bimetallic complexes of stoichiometry Fe2(L)ClO4(ClO4)2 where L are novel unsymmetrical [N10] (L1.2HClO4) and [N12] (L2.2HClO4) macrocyclic ligands, have been prepared. The ligands were obtained from an in situ capping reaction of the reactive substrate, N,N'-bis(N-ethylaniline)hydrazine-1,2-diimine with a mixture of aniline or 1,3-diaminopropane and HCHO in presence of HClO4. The compounds have been characterized by elemental analyses, conductometric, IR, FAB-mass and electronic spectral studies. IR data of complexes suggest coordination from unsymmetrical aza sites as a tridentate (N,N,N) or tetradentate (N,N,N,N) ligand. mu(eff) values of the complexes suggest presence of antiferromagnetically coupled (Fe3+-Fe3+=S5/2-S5/2) spin exchange. M?ssbauer parameters of the complexes support (+/-3/2)-->(+/-1/2) nuclear transition in high-spin configurations of Fe(III) nuclei of the homo-bimetallic complexes with the presence of Kramer's double degeneracy.  相似文献   
758.
This study aimed at assessing the effect of gum arabic (Acacia senegal) oral treatment on the metabolic profile of chronic renal failure (CRF) patients. A total of 36 CRF patients (under regular haemodialysis) and 10 normal subjects participated in this study. The patients were randomly allocated into three groups-group A: 12 CRF patients under low-protein diet (LPD) (<40 g day(-1)) and gum arabic (50 g day(-1)) treatment; group B: 14 CRF patients under LPD and gum arabic, iron (ferrous sulphate, 200 mg day(-1)) and folic acid (5 mg day(-1)) treatment; group C (control group): 10 CRF patients under LPD and iron and folic acid treatment and group D: 10 normal volunteers (on normal diet) under daily dose of 50 g gum arabic. Each of the above treatments was continued for three consecutive months. Blood samples were collected from each subject before treatment and twice per month "pre-dialysis" for 3 months. Biochemical parameters measured were: serum urea, serum creatinine, serum uric acid, serum calcium and serum phosphorus. By the end of the 3 months of treatment, serum urea levels significantly decreased by 31.2 and 44.18% for group A and B, respectively, compared with the baseline (0.01 < p < 0.001) and control group (p < 0.05). Serum creatinine levels significantly decreased in the groups of gum users (A, B and D) by 9.94, 12.65 and 11.7%, respectively, compared with the control group (p < 0.001). There was a significant decrease (p < 0.05) in serum uric acid levels by 14 and 19.9% for group A and B, respectively, compared with the baseline. Serum calcium levels increased by 12.64, 15.75 and 8.75% for group A, B and D, respectively, and these increases were significantly different (0.05 < p < 0.001) from baseline and control group for groups A and B. Serum phosphorus levels significantly decreased by 22.54% for group A, 17.69% for group B and 7.71% for group D, compared with the baseline (0.05 < p < 0.001). From this study, we conclude that oral administration of gum arabic could conceivably alleviate adverse effects of CRF.  相似文献   
759.
Journal of Fluorescence - Novel alkylated heterocyclic chalcone (E)-1-(2-(allyloxy)phenyl)-3-(9-ethyl-9H-carbazol-3-yl)prop-2-en-1-one (AECO) with extended π-bond was prepared by the...  相似文献   
760.
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