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1.
Objective To study on the role of thymus transplantation for heart allograft in rats. Methods Vascularized heart-thymus combined transplantation was performed with microsurgical technique. Graft survival, histopathology, level of IL-2, IL-4 and its mRNA expression in serum and cardiac grafts were investigated. Results Heart-thymus combined transplantation achieved effect in the prolongation of cardiac graft survival with short-term administration of cyclosporine. Conclusions Vascularized thymus transplantation induced immune tolerance in thymectomized rats.  相似文献   

2.
Objective To establish and improve the model of heart-thymus composite transplantation. Methods Vascularized both lobes of the thymus is transplanted heterotopically with the heart as a composite graft in rats. This technique was developed and assessed, and viability of the grafts was evaluated histologically. Results Donor operation costed 38.5 ± 3.52 min, vascular anastomosis costed 25.0 ± 3.28 min, operating successful rate was 90%, acute rejection was observed in SD-Wistar group, viable thymus with normal microarchitecture was maintained in Wistar-Wistar group. Conclusions The improved novel technique for combined heart-thymus transplantation is a valuable method for study of the role of thymus in transplantation immunity.  相似文献   

3.
Objective To observe the effect of FTY720 and ICAM-1 mAb mono and combination therapy in cardiac allo-transplantation in rats. Methods Rats were randomly assigned to 9 groups, heart allo-transplantation were performed in abdominal site with micro-surgical technique. Recipients with allografts were treated with different doses of FTY720 and (or) ICAM-1 mAb. Graft survival, histopathology and level of serum IL-2, IFN-γ, IL-4, IL-10 were investigated. Results Low doses of FTY720 (1mg/kg) combined with ICAM-1 mAb achieved synergistic effect in the prolongation of cardiac graft survival, combination index(CI)=0.67. Conclusion Concomitant therapy of FTY720 and ICAM-1 mAb achieved a synergistic effect in the prolongation of heart allograft survival in rats.  相似文献   

4.
Objective To establish and improve the model of heart-thymus composite transplantation. Methods Vascularized both lobes of the thymus is transplanted heterotopically with the heart as a composite graft in rats.This technique was developed and assessed, and viability of the grafts was evaluated histologically. Results Donor operation costed 38. 5 ± 3. 52 min, vascular anastomosis costed 25.0 ± 3. 28 min, operating successful rate was 90%, acute rejection was observed in SD-Wistar group, viable thymus with normal microarchitecture was maintained in Wistar-Wistar group. Conclusions The improved novel technique for combined heart-thymus transplantation is a valuable method for study of the role of thymus in transplantation immunity.  相似文献   

5.
Objective To observe the effect of FTY720 and ICAM-1 mAb mono and combination therapy in cardiac silo-transplantation in rats. Methods Rats were randomly assigned to 9 groups, heart allo-transplantation were performed in abdominal site with micro-surgical technique. Recipients with allografts were treated with different doses of FTY720 and(or) ICAM-1 mAb. Graft survival, histopathology andlevel of serum IL-2, IFN-γ, IL-4, IL-10were investigated. Results Low doses of FTY720 (lmg/kg) combined with ICAM-1 mAb achieved synergistic effect in the prolongation of cardiac graft survival, combination index(CD =0.67. Conclusion Concomitant therapy of FTY720 and ICAM-1 mAb achieved a synergistic effect in the prolongation of heart allograft survival in rats.  相似文献   

6.
Objective To observe IL-1B, IL-6 and TNF-a level change of the joint fluid in the experimental knee joint degeneration and the effect of the local loosening therapy. Methods Thirty rabbits were divided into 3 groups at random: ten in the normal contrast group, ten in the blank model group and ten in the loosening therapy group to observe the IL-1B, IL-6 and TNF-a change of the joint fluid before and after the treatment in each group. Result IL-1B, IL-6 and TNF-a level in the blank model group was obviously higher than that in the normal group. (P<0.05). IL-1B, IL-6 and TNF-a level in the treatment group was obviously lower than that in the normal group. (P<0.05). Conclusions 1) IL-1B, IL-6 and TNF-a level of the joint fluid in the blank model group was obviously higher than that in the normal group. 2) Loosening soft tissues of the knees can improve IL-1B, IL-6 and TNF-a level of the joint fluid. Foundation item: Project (99JJy2081) supported by the Natural Science Foundation of Hunan Province  相似文献   

7.
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   

8.
Two novel mixed-ligand complexes, [M(phen)2(ans)2]·H2O (M = Cd(II) 1, Zn(II) 2; phen is 1, 10-phenanthroline, and ans is 4-aminonaphthalene-1-sulfonate), were obtained from the reaction of 1, 10-phenanthroline, sodium 4-aminonaphthalene-1-sulfonate tetrahydrate and acetate in mixed solvents. Interaction of the complexes with calf thymus DNA (ctDNA) were investigated using UV-vis absorption spectra, luminescence titrations, steady-state emission quenching by [Fe(CN)6]4−, DNA competitive binding with ethidium bromide (EB) and viscosity measurements. The experimental results indicate that there exist two interaction modes between the complexes and DNA, namely the electrostatic interaction and intercalation, with the binding constants of 1.82 × 105 M−1 for 1 and 4.78 × 104 M−1 for 2 in buffer of 50 mM NaCl and 5 mM Tris-HCl (pH 7.0). Funded by Key Project of the National Natural Science Foundation of China (No. 60537050)  相似文献   

9.
To research juglone's immunology regulation, several perspectives including immunology regulation, lymphocyte proliferation, and cytokines were presented.The index of thymus and spleen, total supperoxide dismutase activity (T-SOD), serum malondialdehyde (MDA), content of nitrogen oxide (NO), the anti-superoxide anion ability, the suppressing hydroxy radical ability, contents of reduced glutathione (GSH) in thymus, total antioxidationability (T-AOC) and the level of mouse lysozyme (LZM) in plasma were measured. LPS-induced B thymocytes proliferation was measured by MTT assay.In the low-immunity model group, MDA and NO levels were decreased (p<0.001). Juglone improved lysozyme (LZM), GSH contents in thymus, T-AOC, T-SOD activity, the anti-superoxide anion ability (anti- O2-) (p<0.001).In the stimulation immunity model group, MDA and NO levels (p<0.05), anti- O2- and T-SOD activity (p<0.05) were up-regulated, whereas LZM, T-AOC contents were down-regulated.juglone has a significant effect, which promotes cell regeneration and function recovery, also may alleviate oxidative damage; juglone possesses a dual regulating effect on humoral immunity in mice.  相似文献   

10.
A new method of extracting chlorogenic acid from flos lonicerae, and treating the materials with enzyme before being extracted by ethanol is developed, and the optimum conditions are also investigated in detail. Three important factors, enzyme dosage, treatment time and treatment temperature are adapted to optimize the extraction process. The experimental results show that the extract yield of flos lonicerae and chlorogenic acid can be obviously increased by the cellulase treatment, 61.5 mg chlorogenic acid is obtained from 1.00 g flos lonicerae at most. The optimal temperature of enzymatic treatment is 40-50 ℃. Compared with the use of single cellulase, the combined treatment of cellulase and pectinase increase the extract yield obviously but fail to improve that of chlorogenic acid.  相似文献   

11.
The preparation technique and properties of Ag-type inorganic antibiotic material carried by Al2O3 were studied. The results show that the material has good antibiotic and safety properties, the acute toxicity taken by stomata is LD 50>8 000 mg/kg (little and big white rats), and the normal quantity in subacute toxicity test is 80 mg/(kg · d). The better mass fraction of doping Ag2O in antibiotic material carried by Al2O3 is 4%–8%, and the optimal sintering temperature is from 1 000 °C to 1 100 °C. Foundation item: Project (2002AA327090) supported by National High Technology Research and Development Program of China  相似文献   

12.
A new support vector machine (SVM) optimized by an improved particle swarm optimization (PSO) combined with simulated annealing algorithm (SA) was proposed. By incorporating with the simulated annealing method, the global searching capacity of the particle swarm optimization(SAPSO) was enchanced, and the searching capacity of the particle swarm optimization was studied. Then, the improyed particle swarm optimization algorithm was used to optimize the parameters of SVM (c,σ and ε). Based on the operational data provided by a regional power grid in north China, the method was used in the actual short term load forecasting. The results show that compared to the PSO-SVM and the traditional SVM, the average time of the proposed method in the experimental process reduces by 11.6 s and 31.1 s, and the precision of the proposed method increases by 1.24% and 3.18%, respectively. So, the improved method is better than the PSO-SVM and the traditional SVM.  相似文献   

13.
Magnetic nanoparticles (Fe304) were prepared by chemical precipitation method using Fe^2+ and Fe^3+ salts with sodium hydroxide in the nitrogen atmosphere. Fe3O4 nanoparticles were coated with human serum albumin(HSA) for magnetic resonance imaging as contrast agent. Characteristics of magnetic particles coated or uncoated were carried out using scanning electron microscopy and X-ray diffraction. Zeta potentials, package effects and distributions of colloid particles were measured to confirm the attachment of HSA on magnetic particles. Effects of Fe3O4 nanoparticles coated with HSA on magnetic resonance imaging were investigated with rats. The experimental results show that the adsorption of HSA on magnetic particles is very favorable to dispersing of magnetic Fe3O4 particles, while the sizes of Fe3O4 particles coated are related to the molar ratio of Fe3O4 to HSA. The diameters of the majority of particles coated are less than 100 nm. Fe3O4 nanoparticle coated with HSA has a good biocompatibility and low toxicity. This new contrast agent has some effects on the nuclear magnetic resonance imaging of liver and the lowest dosage is 20μmol/kg for the demands of diagnosis.  相似文献   

14.
Determinationoffracturetoughnesofbritlematerialsisofgreatimportanceinminingandgeologicalenginering.Avarietyofspecimengeomet...  相似文献   

15.
为了解决资料稀缺流域非点源污染研究中分布式物理模型无法直接应用的问题,基于SWAT(Soil and Water Assessment Tool)模型,采用参数移植法构建了无径流无泥沙资料的西充河流域(西充境内)非点源污染模拟方案。验证流域模拟结果良好(R2>0.8,NSE>0.5)表明SWAT模型径流泥沙参数可用于相似流域移植,研究区西阳寺断面TP(R2=0.52,NSE=0.69,Re=35%)水质模拟结果说明基于径流泥沙参数移植后的SWAT模型可用于进一步非点源污染模拟研究。  相似文献   

16.
A method to estimate the probabilistic density function (PDF) of shear strength parameters was proposed. The second Chebyshev orthogonal polynomial(SCOP) combined with sample moments (the origin moments) was used to approximate the PDF of parameters. X^2 test was adopted to verify the availability of the method. It is distribution-free because no classical theoretical distributions were assumed in advance and the inference result provides a universal form of probability density curves. Six most commonly-used theoretical distributions named normal, lognormal, extreme value Ⅰ , gama, beta and Weibull distributions were used to verify SCOP method. An example from the observed data of cohesion c of a kind of silt clay was presented for illustrative purpose. The results show that the acceptance levels in SCOP are all smaller than those in the classical finite comparative method and the SCOP function is more accurate and effective in the reliability analysis of geotechnical engineering.  相似文献   

17.
The anti-inflammatory effect and mechanism of Usnic acid (UA) were explored on lipopoly-saccharide (LPS)-stimulated RAW264.7 cell line.The effects of UA on pro-inflammatory cytokines including tumor necrosis factor-alfa (TNF-α),interleukin-6 (IL-6) and interleukin-1 beta (IL-1β),pro-inflammatory mediators such as nitric oxide (NO),inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) were studied by sandwich ELISA,real-time PCR and western blot analyses.Similarly,the effect of UA on anti-inflammatory cytokine interleukin-10 (IL-10) and anti-inflammatory mediator heme oxygenase-1 (HO-1) were also studied following the same methods.Furthermore,nuclear factor-κB (NF-κB) was assayed by immunocytochemistry.The results showed that UA has anti-inflammatory effect by down-regulatinng iNOS,COX-2,IL-1β,IL-6 and TNF-α,COX-2 gene expression through the suppression of NF-κB activation and increasing anti-inflammatory cytokine IL-10 and anti-inflammatory mediator HO-1 production.  相似文献   

18.
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   

19.
A practical catalytic method to oxidize α-ionone with molecular oxygen using N-hydroxyphthalimide(NHPI) combined with acetylacetone cobatt(II) (Co(acac)2) was developed, and the probable catalytic mechanism was proposed. The influences of the reaction conditions on conversion of α-ionone and the selectivity of the major product (5-keto-α-ionone) were investigated, and the technical parameters for 5-keto-α-ionone were optimized. The results show that the primary product is 5-keto-α-ionone, and by-products include epoxy-α-ionone, as well as rearrangement products 4-keto-β-ionone and epoxy-β-ionone, which are characterized by infrared spectra, proton nuclear magnetic resonance spectra, mass spectra and elemental analysis. The selectivity of 5-keto-α-ionone and the conversion of α-ionone are 55.0% and 97.0%, respectively, when 30%(molar fraction) NHPI, 1.0%(molar fraction) Co(acac)2 and no solvent are employed under O2 pressure of 1.0 MPa and the reaction temperature of 65 °C for 11 h. The procedure shows good reproducibility in the parallel experiments. Foundation item: Project(50573019) supported by the National Natural Science Foundation of China  相似文献   

20.
Objective Study on the effect of NF-κB in ox-LDL injured HUVEC-304 and the intervention with the serum of Tongmai Decoction. Methods Tongmai Decoction herbage-contained serum was made by the serum pharmacology methods, then the HUVEC-304 cells were divided into 5 groups and incubated for 24 h: 1) normal group; 2) fetal calf serum group; 3) ox-LDL group; 4) simvastatin group; 5) Tongmai Decoction group. RT-PCR was used to determine the mRNA of NF-κB in the cells, Western Blot Assay was used to determine the protein content of NF-κB in the cells. Results 1) Compared with the cells in normal group and serum control group, the endothelial cells in ox-LDL group are seriously injured, while those in Tongmai Decoction group grow better; 2) Compared with the cells in normal group and fetal calf serum group, the expressions of NF-κB gene and protein are up-regulated in ox-LDL group(P<0.05, P<0.01); 3) Compared with the cells in ox-LDL group, the expression of NF-κB gene and protein in Tongmai Decoction group are significantly down-regulated, there is no difference between Tongmai Decoction group and simvastatin group(PP>0.05). Conclusion Tongmai Decoction can protect the injured endothelial cells, up-regulate the expressions of NF-κB gene and protein content. Foundation item: Project (02jjy3034) supported by the Nature Science Foundation of Hunan Province  相似文献   

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