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1.
Objective Tacrolimus is an immunosuppressive drug with narrow therapeutic range and wide interindividual variation in its pharmacokinetics. Tacrolimus is a substrate of cytochrome P450(CYP)3A5. The aim of this study was to evaluate whether the A6986G polymorphism is associated with tacrolimus concentration/dose ratio.Methods Fifty-two Chinese renal transplant patients were enrolled in this study. Their body weight, dosage and concentration of tacrolimus were observed. CYP3A5 genotype was determined by polymerase chain reaction followed by restriction fragment length polymorphism analysis. Results A significant association was found between tacrolimus levels per dose/kg/d and CYP3A5 gene A6986G polymorphism(P<0.001). The CYP3A5 * 3 * 3 patients have a significantly higher tacrolimus level/dose than CYP3A5 * 1 * 1 and CYP3A5 * 1 * 3. Conclusions CYP3A5 gene A6986G polymorphism is associated with tacrolimus pharmacokinetics and dose requirements. Pharmacogenetic methods could be employed prospectively to help the dose selection and to individualize immunosuppressive therapy according to the result.  相似文献   

2.
Co/Al2O3 Fischer-Tropsch synthesis catalysts with different cobalt loadings were prepared using incipient wetness impregnation method. The effects of cobalt loading on the properties of catalysts were studied by means of X-ray diffraction (XRD), temperature programmed reduction (TPR), hydrogen temperature programmed desorption (H2-TPD) and O2 titration. Co-support compound formation can be detected in catalyst system by XRD.For the Co/Al2O3 catalysts with low cobalt loading, CoAl2O3 phase appears visibly. Two different reduction regions can be presented for Co/Al2O3 catalysts, which belong to Co3 O4 crystallites (reduction at 320 ““C) and cobalt oxidealumina interaction species (reduction at above 400℃). Increasing Co loading results in the increase of Co3 O4 crystallite size. The reduced Co/Al2O3 catalysts have two adsorption sites, and cobalt loading greatly influences the adsorption behavior. With the increase of cobalt loading, the amount of low temperature adsorption is increased, the amount of high temperature adsorption is decreased, and the percentage reduction and cobalt crystallite size are increased.  相似文献   

3.
The energy transfer and upconversion of Er^3+/Yb^3+ co-doped TeO2-TiO2-K2O glasses upon excitation with 976 nm lasers diode were studied. The tellurite glasses were prepared by conventional melting methods. Their optical properties and sensitization upconversion spectra were performed. The dependence of green upconversion lu- minescence intensity on the mole ratio of Yb^3+ to Er^3+ and Er^3+ concentration were discussed in detail. When the mole ratio of Yb^3+ to Er^3+ is 25/1 and Er^3+ concentration is 0.1% (mole fraction), or when the mole ratio of Yb^3+ to Er^3+ is 10/1 and Er^3+ concentration is 0.15 %, the optimal upconversion luminescence intensity is obtained. The obtained glasses can be one of the potential candidates for lasers-diode pumping microchip solid-state lasers.  相似文献   

4.
Objective To observe the apoptosis of osteosarcoma MG-63 cells induced by As2O3 and to explore its possible mechanisms. Methods The flowcytometric analysis and transmission electronmicroscope were performed to investigate the inducing apoptosis and inhibitative of As2O3 on osteosarcoma MG-63 cells. In order to study mechanism of apoptosis in MG-63 cells treated with As2O3, microarray was performed. The down-regulated gene was confirmed by RT-PCR, Northern-blotting. Results After treated with As2O3, hypodiploid peak before G0/G1 phase was observed in MG-63 cells through FCM analysis. Loss of microvilli, condensation and fragmentation of nuclear chromatin, condensation of cytoplasmic organelles, dilatation of the endoplasmic reticulum shrinkage of cells and alterations in cell membranes and apoptosis bodies which were observed in MG-63 cells treated with As2O3 by transmission electronmicroscope. The results of microarray show that As2O3 induced MG-63 cell apoptosis involves down-regulation of IEX-1 and the down-regulated gene is confirmed by RT-PCR and Northern-blotting. Conclusion The results show that As2O3 selectively inhibits growth of the solid tumor MG-63 cells by triggering apoptosis and indicates MG-63 induced by As2O3 cell apoptosis may through the IEX-1 pathway. Foundation item: Project (02JTY1005) supported by the Foundation of Science & Technology Department of Hunan Province; project (Y02-033) supported by the Foundation of Health Department of Hunan Province  相似文献   

5.
1 INTRODUCTION Conducting polymers, such as polyaniline (PANI), polypyrrole (PPY) and polythiophene, have attracted much attention as an enzyme-immobilizing matrix for biosensors [1?3]. Conducting polymers are known to be compatible with biological molecules in neutral aqueous solutions. Due to the reversibility doping-undoping processes and the rapid electron transfer, the conducting polymers are promising in the immobilization of biomolecules and fabrication of efficient biosensors[4]…  相似文献   

6.
SrBi2.2 Ta2O9 (SBT) thin film with thickness of 2 μm was successfully prepared by sol-gel method, using strontium acetate semihydrate [Sr(CH3 COO)2 · 1/2H2O] and bismth subnitrate [BiO(NO3)], and tantalum ethoxide [Ta(OCH2CH3)5] as source materials, glacial acetic and ethylene glycol as solvents. The X-ray diffraction (XRD) and transmission electron microscope(TEM) results indicate that SBT layer-perovskite phase obtained has to be single phase, SBT thin film is formed after being annealed at 800 °C for for 1 min. The typical hysteresis loop of SBT thin film on Pt/Ti/SiO2/Si is obtained, and the measured polarization value of the SBT thin film is 4. 2 μ/C/cm2. Foundation item: Project (HIT. 2001. 67) supported by the Scientific Research Foundation of Harbin Institute of Technology; project (50172012) supported by the National Natural Science Foundation of China  相似文献   

7.
Period of arnold transformation and its application in image scrambling   总被引:1,自引:0,他引:1  
With the security problem of image information as the background, some more properties of the period of Arnold transformation of two-dimension were studied by means of introducing a integer sequence. Some new results are obtained. Two interesting conjectures on the period of Arnold transformation are given. When making digital images scrambling by Arnold transformation, it is important to know the period of the transformation for the image. As the application of the theory, a new method for computing the periods at last are proposed. Foundation item: Project (10471020) supported by the National Natural Science Foundation; project (04JJ6028) supported by the Natural Science Foundation of Hunan Province; project (03A002) supported by the Ministry of Education of Hunan Province  相似文献   

8.
In this paper, we apply a cone theoretic fixed point theorem to obtain sufficient conditions for the existence of multiple positive periodic solutions to the higher-dimensional functional difference equations of the form:
. Foundation item: Project(10471153) supported by the National Natural Science Foundation of China; project supported by the Natural Science Foundation of Central South University  相似文献   

9.
The action between imidazolinyl-quaternary-ammonium-salt(IQAS) molecule and Fe atom was studied, and the influence of the alkyl group connected with N atom of imidazoline ring on corrosion inhibition efficiency was explored. Quantum chemical methods, HF/6 - 31 G and HF/Lan L2 dz, were applied successively to calculate the parameters such as front molecular orbit energy of IQAS Ⅰ-Ⅳ and chemical adsorption for IQAS Ⅰ-Ⅳ and Fe atom. The corrosion inhibition efficiency was measured with the weight loss method of carbon steel samples in acidic solution and oil field sewage. Based on the theoretical analyses and experimental results, it is concluded that N-Fe coordination bond is formed between IQAS molecule and Fe atom, corrosion inhibition efficiency is decreased in the following order(from large to small) : IQAS Ⅳ, IQAS Ⅲ, IQAS Ⅱ , IQAS Ⅰ.  相似文献   

10.
A comprehensive assessment index system was established. The mechanical recycling process of printed circuit board was evaluated according to the comrehensive evaluation index system using the fuzzy analytic hierarchy process. A process assessment software system of mechanical recycling was established to evaluate different recycling technologies. And the software system was developed in the environment of VB 6.0 and Access 2000. Foundation item: Project (50375044) supported by the National Natural Science Foundation of China; project (05021008) supported by Annual Emphasis Project of Anhui Province  相似文献   

11.
By means of Malvern laser particle size analyzer and scanning electron microscopy, the influences of seed size and number on agglomeration in Bayer process were investigated. Agglomeration is almost finished in 8 h, seeds, below 5 μm, especially below 2 μm, gather together rapidly and almost disappear in 8 h. In the same supersaturation of aluminate solution and seed size, the smaller the number of seed is, the bigger the degree of agglomeration is. With the same primary number of seed, the agglomeration of larger seed is superior to that of small seed, and the agglomeration does not happen among the coarse seeds. The agglomeration mainly happens among fine particles, and the combinations among the fine particles are unconsolidated.  相似文献   

12.
Objective This pilot-study was designed to evaluate the feasibility of cell transplantation into guinea pig cochlea. Methods Marrow stromal cells were labeled with DAPI, and then implanted into the cochlea of guinea pig. The existence and differentiation trend were observed roughly two weeks later by histologic analysis. Results Transplant-derived marrow stem cells survived in cochlea two weeks later with a trend of attaching to cochlear architecture but not differentiate into neuron. Conclusions Transplant-derived marrow stem cells can survive in cochlea, and cell transplantation may be a useful strategy in inner ear diseases. Foundation item: Project (30000094) supported by the National Nature Science Foundation of China; project supported by the Postdoctoral Foundation of Central South University  相似文献   

13.
Experimental study on wear failure course of gas-valve/valve-seat in engine   总被引:2,自引:0,他引:2  
The wear failure course of gas-valve/valve-seat in engine was investigated with a simulating tester. The results show that the failure of the contact conical surface is mainly caused by the elastic and plastic deformation and the fatigue micro-crack and spalling. The creep-deformation and corrosion atmosphere accelerated wear failure course at the high temperature. The wear failure course of the gas-valve/valve-seat in engine follows general wear rules of mechanical elements, but the rate of wear in the sharp wear stage is faster. Foundation item: Project supported by Postdoctoral Foundation of Central South University; project (04B035) supported by the Youth Foundation of Hunan Province Education Bureau  相似文献   

14.
Fe-Al intermetallics with remarkable high-temperature intensity and excellent erosion, high-temperature oxidation and sulfuration resistance are potential low cost high-temperature structural materials. But the room temperature brittleness induces shape difficult and limits its industrial application. The Fe-Al intermetallic coatings were prepared by high velocity arc spraying technology with cored wire on 20G steel, which will not only obviate the problems faced in fabrication of these alloys into useful shapes, but also allow the effective use of their outstanding high-temperature performance. The Fe-Al/WC intermetallic composite coatings were prepared by high velocity arc spraying technology on 20G steel and the oxidation performance of Fe-Al/WC composite coatings was studied by means of thermogrativmetic analyzer at 450, 650 and 800°C. The results demonstrate that the kinetics curve of oxidation at three temperatures approximately follows the logarithmic law. The composition of the oxidized coating is mainly composed of Al2O3, Fe2O3, Fe3O4 and FeO. These phases distribute unevenly. The protective Al2O3 film firstly forms and preserves the coatings from further oxidation. Foundation item: Project(50235030) supported by the National Natural Science Foundation of China; Project(98BK014) supported by the Foundation of State Economy Trade Committee of China  相似文献   

15.
Through theoretical analysis and experiments, the viscoelastic mechanical model of optical fiber coupler in the process of fused biconical taper was established, and the numerical analysis in non-uniform temperature field was made. The results show that the rheological parameters, such as drawing speed and fused temperature, have a tremendous influence on stress distribution and performance of optical fiber coupler, especially the influence of fused temperature. The change of fused temperature by 5 ℃ can lead to the change of the maximum stress by 30% and stress difference by 20% in the same cross section. The change of temperature gradient by 3% can result in the change of stress difference by 90%. In the present condition of rheological technology, rheological defects such as crystallizations and microcracks are easy to generate in the optical fiber coupler.  相似文献   

16.
Objective To investigate the change of protein expression of lung tissue of rabbit after ischemic preconditioning (IP) and try to elucidate the potential protective mechanism of IP. Methods 12 domestic rabbits were randomly divided into group IP and group control (6 rabbits in each group). All the left lungs were afflicted by ische mia-reperfusion injury except that those in group IP were subject to IP prior to ischemic phase. 2-DE was employed to separate the total protein of the lung tissue. PDQuest analysis software was used to distinguish the differently expressed protein spot. MALDI-TOF-MS and Mascot database searching were exploited to identify these proteins. Results 1) IP attenuated the ischemia-reperfusion lung injury. 2) The proteomic analysis showed 35 target proteins, of which 17 were characterized such as phosphatidylinositol 3-kinase(PI3k) delta catalytic subunit. Conclusions 1) Proteomic is a promising tool to investigate the IP and ischemia-reperfusion lung injury. 2) That IP inhibits inflammatory cascades through phosphatidylinositol 3-kinase signal transduction pathway may be one of its protective mechanism. Foundation item: Project(2004036433) supported by the Postdoctoral Science Foundation of China; project(B2004024) supported by the Science Foundation of Public Health Bureau of Hunan Province  相似文献   

17.
In order to amend the superficial performance of palygorskite and improve its application, the natural palygorskite(NP) was treated in the dipping and ionic exchanging experiments using 6 mol/L hydrochloric acid treatment. The performance and pore structure of the treated palygorskite(TP) were investigated by means of microscope analyses, FT-IR, XRF, BET-SSA and full hole distribution analytical techniques. The results show that the hydrochloric acid treatment can make the gracile and aggregating compact crystal bundles inside palygorskite clay broken and dispersed, the roughness of microcrystalline surface increases, which not only can dissolve or remove dolomite but vary the superficial performance of palygorskite to some degree. The specific surface area and pore volume increase a lot, while the mean pore size decreases. The pore structure of TP changes remarkably compared with that of NP after 6 mol/L hydrochloric acid treatment, and the relevant physicochemical performance can be improved.  相似文献   

18.
Coating of Fe, Ni on α-alumina microspheres by heterogeneous precipitation   总被引:1,自引:0,他引:1  
1INTRODUCTION Themagneticmetal coatedceramicoxides,core shellstructuralcompositematerials,inwhichthinmetallicfilmsarecoatedonaceramicoxide matrixwithmicrometerparticlesizes,areattrac tiveduetothecombinationofthefunctionalchar acteristicsofmetalsandmechanicalpropertiesoftheceramicmatrix.Theceramic basedtransition metal coated,core shellcompositessuchasNi coatedAl2O3[1],Fe coatedAl2O3[2],FeNi coated Al2O3[3]orCoFe coatedSiO2[4],havebeenfoundtoexhibitinterestingfunctionalperformancesdue…  相似文献   

19.
1 INTRODUCTIONThe use of inert or non-consumable anodes forreplacement of consumable carbon anodes in Hall-H啨roult electrolysis cells for the production of alu-minum has been a technical and commercial goalfor many decades .In the present process ,consumable carbon an-odes are used,andthe anode product is CO2. Withaninert anode ,the cell reaction will be :Al2O3=2Al +23O2(1)The basic requirements for aninert anode are :1) to exhibit a lowcorrosion rate in the high tem-perature melts an…  相似文献   

20.
An automatic brush-plating system was developed for component remanufacturing. With this system, Ni/nano-alumina composite coatings from an electrolyte containing 20 g/L nano-alumina particles were prepared. Microstructure, surface morphology, microhardness and wear resistance of automatically plated coating and manually plated coatings were investigated comparatively. The results show that the automatically plated coatings are relatively dense and uniform and have lower friction coefficient of 0.089 under lubricant condition, when compared with manually plated coatings with friction coefficient of 0.14. Foundation item: Project(50235030) supported by the National Natural Science Foundation of China; Project(G1999065009) supported by the National Basic Research Program of China  相似文献   

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