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  • Author or Editor: Q. Zhang x
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Abstract  

Two sufficient conditions for a finite group G to be p-supersolvable have been obtained. For example (Theorem 1.1), let N be a normal subgroup of G such that G/N is p-supersolvable for a fixed odd prime p and let N p be a Sylow p-subgroup of N. Suppose that N is p-solvable and Ω1(N p) is generated by the subgroups of order p of N p which are normal in N G(N p). Then G is p-supersolvable.

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Fingernails of pathologically diagnosed normal people, light esophageal epitheliosis patients, severe esophageal epitheliosis patients and esophageal cancer patients were irradiated and their elemental contents were determined by INAA. Multivariate statistical treatment of Ca, Cl, K. Mg, Se and Zn data shows that esophageal cancer patients are distinguishable from non-cancer patients. The accuracy computed by neural networks is greater than 80%.

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By using 188Re as a radiotracer, the extraction behavior of Re(VII) by a tertiary amine extractant N-235 from HCl and the back-extraction behavior of Re(VII) by HNO3 and ammonia were studied. A chemical separation procedure, which combined the acid alumina column and solvent extraction was established. The procedure was rapid and efficient for the separation of 186Re from 186W irradiated by 16 MeV deuterons. No-carrier-added 186ReO4 saline solution with high specific volume activity was obtained. The overall recovery yield of 186Re was about 85%.

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High-performance capillary electrophoresis with amperometric detection (CE-AD) has been used for analysis of eight bioactive components of the leaves, stems, and roots of Valeriana wallichii DC, after a relatively simple extraction procedure with ethanol. Under the optimum conditions, the eight components can be well separated or (apigenin and luteolin) separated nearly to baseline within 23 min by use of 50 mM borax (pH 9.2) as running buffer and a separation potential of 16 kV. Linearity was excellent over two orders of magnitude of concentration and detection limits (S/N = 3) ranged from 1.7 × 10−7 to 1.8 × 10−8 g mL−1. This method was used for comparison of the concentrations of the bioactive compounds in different parts of the plant on the basis of their electropherograms or ‘characteristic electrochemical profiles’. Assay results were satisfactory.

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Th17 cells, a class of CD4+ T cells, have been identified as novel effector cells, which play a pivotal role in several inflammatory and autoimmune diseases. 1,25-Dihydroxyvitamin D3 (1,25(OH)2D3), the active form of vitamin D, has emerged as a direct regulator of immune system function in humans. Accumulating reports demonstrated that 1,25(OH)2D3 possessed anti-inflammatory activity on Th17 cells to maintain immunologic homeostasis. This report will review the novel immune regulatory role of 1,25(OH)2D3 in its potential use for Th17 cell-related inflammatory and autoimmune conditions.

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Salt stress is one of the major abiotic stress which severely limits plant growth and reduces crop productivity across the world. In the present study, the effects of exogenous pyridoxal-5-phosphate (vitamin B6, VB6) on seedling growth and development of wheat under salt stress were investigated. The results showed that exogenous application of pyridoxal-5-phosphate (VB6) significantly increased the RWC, biomass, the concentration of photosynthetic pigments, proline, the activities of superoxide dismutase (SOD), catalase (CAT), peroxidase (POD), together with decreasing the content of Malondiadehyde (MDA) and hydrogen peroxide (H2O2) in wheat leaves under salt stress. Meanwhile, the transcript level of P5CR, P5CS, SOD, TaSOS1 and TaSOS4 were also up-regulated after treatment with pyridoxal-5-phosphate. VB6 acts as a signal in regulating the activities of plant antioxidant enzymes and SOS pathway to improve resistance to salt stress. The current study results may give an insight into the regulatory roles of VB6 in improving salt stress and VB6 could be an easily and effective method to improve salt-stress tolerance to wheat in the field condition. It is urgency to understand the molecular mechanism of VB6 to enhance the salt tolerance of wheat in the next work.

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Abstract  

Twenty-seven pairs of head hair from mothers and their new-born infants were collected at the time of delivery in a hospital in Beijing. The total mercury content in the hair samples was determined by INAA. The correlation between mercury content in hair of mothers and their new-born infants has been investigated. In addition, the change of Hg content in pregnant women's hair during their pregnancy was also studied by INAA and SRXRF. The results indicate a significant positive correlation between the mercury content in maternal and infant head hairs (r=+0.862, p<0.001). The average content of Hg in infant and maternal hairs was 0.66±0.31 g/g and 0.59±0.25 g/g, respectively. The infant level exceeded the maternal by 12%. The Hg content in maternal head hair gradually reduced during pregnancy. Further, the methylmercury (Me–Hg) content in 3 maternal hair samples was analyzed by GC(EC). The Me–Hg was in accordance with the total mercury content. Thus a conclusion can be drawn that damage to the infant from Hg occurred in the early stages of pregnancy.

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Summary

A simple hydrolysis method has been developed for determination of phenylethanoid glycosides in Lamiophlomis rotata (L.R.). Different kinds of phenylethanoid glycosides were hydrolyzed in hydrochloric acid solution to produce corresponding phenethyl alcohols and cinnamic acids, mainly containing hydroxytyrosol, homovanillyl alcohol, 3,4-dimethoxyphenethyl alcohol, caffeic acid, fumalic acid and 3,4-dimethoxycinnamic acid. The six analytes could be determined simultaneously by high-performance liquid chromatography (HPLC). The effects of mobile phase, pH and concentration of running buffer, detection wavelength, flow rate and injection volume were also investigated. Under the optimum conditions, the six hydrolyzates could be perfectly separated within 45 min. The response was linear over four orders of magnitude with detection limits (S/N = 3) ranging from 1 × 10−8 to 1.5 × 10−4 mol L−1 for the analytes. The method has been successfully applied to the analysis of real sample Du-Yi-Wei capsule and Qi-Zheng-Yan-Tong patch, with satisfactory results.

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Abstract  

A fully automated adiabatic calorimeter controlled on line by a computer used for heat capacity measurements in the temperature range from 80 to 400 K was constructed. The hardware of the calorimetric system consisted of a Data Acquisition/Switch Unit, 34970A Agilent, a 7 1/2 Digit Nano Volt /Micro Ohm Meter, 34420A Agilent, and a P4 computer. The software was developed according to modern controlling theory. The adiabatic calorimeter consisted mainly of a sample cell equipped with a miniature platinum resistance thermometer and an electric heater, two (inner and outer) adiabatic shields, two sets of six junction differential thermocouple piles and a high vacuum can. A Lake Shore 340 Temperature Controller and the two sets of differential thermocouples were used to control the adiabatic conditions between the cell and its surroundings. The reliability of the calorimeter was verified by measuring the heat capacities of synthetic sapphire (α-Al2O3), Standard Reference Material 720. The deviation of the data obtained by this calorimeter from those published by NIST was within ±0.1% in the temperature range from 80 to 400 K.

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A new high-performance liquid chromatography (HPLC) method has been developed and validated for determination of enantiomeric purity of thiazolidine-2-carboxylic acid within a short run time of less than 10 min. The method was based on pre-column derivatization of thiazolidine-2-carboxylic acid with aniline, and complete separation of enantiomers has been achieved on a Chiralcel OD-H analytical column (250 × 4.6 mm) using n-hexane-isopropanol (85:15 v/v) as mobile phase at a flow rate of 1.0 mL min−1 under UV and optical rotation (OR) detection. Detection wavelength was set at 254 nm. Then the effects of mobile phase and temperature on enantioselectivity were further evaluated. The method was validated with respect to precision, accuracy, linearity, limit of detection (LOD), limit of quantification (LOQ), and robustness. The recoveries were between 98.5 and 101.3% with percentage relative standard deviation less than 1.16%. The LOD and LOQ for the aniline derivatives of (+)-thiazolidine-2-carboxylic acid were 4.9 and 16.4 μg mL−1 and for the aniline derivatives (−)-thiazolidine-2-carboxylic acid were 5.1 and 17.2 μg mL−1, respectively.

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