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1.
To investigate the treatment effect of 2-selenium bridged β-cyclodextrin(2-SeCD), a GPX mimic, on the stroke of stroke-prone spontaneously hypertensive rats(SHRSP), fifty-two SHRSP of 8-week old were randomly divided into four groups A, B, C and control group D. The rats of groups A, B, C and D were given 1.0%-1.5% NaCl mass fraction as drinking fluid. After onset of stroke, groups A, B and C were given orally 16.05, 160.5 and 1605 mg*kg-1*day-1 of 2-SeCD, respectively, and group D was given water for 2 weeks. The clinical score of stroke, systolic blood pressure(SBP), survival time of rats were recorded and the histopathologic examinations of their brain and carotid artery were made after decapitation. The clinical scores of stroke after treatment with 160.5 mg*kg-1*day-1(Group B) and 1605 mg*kg-1*day-1(Group C) of 2-SeCD are 2.55±0.98 and 1.98±0.79, respectively, those are obviously lower than that of group D(3.41±0.83, p<0.01). The survival days in group B(10.0±8.6) and group C(14.4±7.9) are longer than that for group D(4.7±2.9, p<0.01). The electron microscope study showed that the endothelium of carotid artery was near to normal in group B and group C, while it was seriously injured in control group D and mildly injured in group A. 2-SeCD may effectively be used to treat the stroke for SHRSP.  相似文献   

2.
To study the effects of Siqi decoction on rats with Myocardial Ischemia, the model of Myocardium Ischemia was made for the Wistar rats cured with posterior pituitary injection through vein in tail. Siqi decoction, Diaoxinxuekang(DK) and Fufangdanshenpian(FD), the latter two drugs of which were effective TCM drugs of anti-Myocardial Ischemia at present, were administrated to the rats with Myocardium Ischemia for 5 days to compare the effect of anti-Myocardium Ischemia as reference drugs by measuring the changes of NO concentration and activity of NOS in the rat blood serum with Myocardial Ischemia. There was a remarkable increase in the NO concentration and activity of NOS in serum in Siqi decoction groups compared with those in control group(p〈0.05). The results of the prevention group in experiment of Siqi decoction are better than those of the cure group. Siqi decoction was really fit for Myocardium Ischemia via increasing NO concentration by stimulating the activity of NOS in serum. The effect of Siqi decoction against Myocardium Ischemia in preventive group is better than the curative that of Siqi decoction in the curative group.  相似文献   

3.
Leymus chinensis seedlings were treated with 0.05--10 mmol/L vitamin E under osmotic stress in the presence of polyethylene glycol(PEG) as the stress reagent. The effects of the different concentrations of exogenous vitamin E on the activities of SOD, POD and free proline, and the MDA contents under drought stress were examined so as to ascertain the mechanism of Leymus chinensis resistance to drought stress and explore the possible preventive measures. The results indicate that the activities of SOD and POD decreased but the free proline and MDA contents increased as drought stress was accentuated, showing an enhancement of oxidative stress that may cause a decline in membrane stabilization. However, the activities of SOD and POD and the free proline content increased, whereas the MDA content reduced in Leymus chinensis pretreated with vitamin E in comparison with that of the control. This indicates that exogenous vitamin E enhanced the antioxidation of Leymus chinensis seedlings. It suggests that cytomembrane can be protected from damage by increasing the free proline content and the activities of SOD and POD that result in enhancing the drought resistance of Leymus chinensis seedlings.  相似文献   

4.
To study the changes between SOD activity and LPO content in serum of the patients with cholecystolithiasis before and after operation, the methods of xanthine oxidase and thiobarbituric acid were applied to this study. The results Show that SOD activity in serum is lower than that in the control group obviously (P<0.01),while LPO content is higher than that in the control group significantly (P<0.01).The method can be used to comprehend the relation between free radical and cholecystolithiasis by determining the SOD activity and LPO content of serum in the patients with cholecystolithiasis.  相似文献   

5.
SHAPE MEMORY EFFECT OF PU IONOMERS WITH IONIC GROUPS ON HARD-SEGMENTS   总被引:1,自引:0,他引:1  
SMPU (shape memory polyurethane) non-ionomers and ionomers, synthesized with poly(c-caprolactone) (PCL), 4, 4'-diphenylmethane diisocyanate (MDI), 1,4-butanediol (BDO), dimethylolpropionic acid (DMPA) were measured with cyclic tensile test and strain recovery test. The relations between the structure and shape memory effect of these two series were studied with respect to the ionic group content and the effect of neutralization. The resulting data indicate that, with the introduction of asymmetrical extender, the stress at 100% elongation is decreased for PU non-ionomer and ionomer series, especially lowered sharply for non-ionomer series; the fixation ratio of ionomer series is not affected obviously by the ionic group content; the total recovery ratio of ionomer series is decreased greatly. After sufficient relaxation time for samples stretched beforehand, the switching temperature is raised slightly, whereas the recovery ratio measured with strain recovery test method is lowered with increased DMPA content. The characterization with FT-IR, DSC, DMA elucidated that, the ordered hard domain of the two series is disrupted with the introduction of DMPA which causes more hard segments to dissolve in soft phase; ionic groups on hard segment enhance the cohesion between hard segments especially at high ionic group content and significantly facilitate the phase separation compared with the corresponding non-ionomer at moderate ionic group content.  相似文献   

6.
谭美军  汤建新  陈洪 《中国化学》2005,23(9):1247-1252
Poly(tetrafluoroethylene) (PTFE) was treated with plasma in a mixture of nitrogen and hydrogen (1 : 2 in volume). X-ray photoelectron spectroscopy (XPS) demonstrated the success of amino group grafting. The as-treated PTFE slices were successively applied to the in situ synthesis of oligonucleotides. With the detection of gold-label-silver-stain, the hybridization signals were recorded with a gel document and analysis system. A target DNA concentration as low as 10 pmol/L could be detected. The complementary and mismatched sequences were distinguished clearly, and the ratio of background-subtracted gray scale values for perfect match : 1 base mismatch : 2 base mismatch : 3 base mismatch was 72 : 44.4 : 22.5 : 11.4. The sensitivity of in situ synthesis system was 1 order of magnitude higher than that of spotting system, and the signal of the former was about 1.5 times stronger than that of the latter under the same target DNA concentration. These plasma modified PTFE slices might open novel prospects for the in situ synthesis of DNA micro-arrays.  相似文献   

7.
To observe the effects of the micronutrients on oxidative and autoimmune destruction of islets so as to prevent a person from the onset and development of type 1 Diabetes Mellitus(T1DM),the interleukin-4 and interleukin-10 expressions of lymphocytes in peripheral blood and spleen of T1DM rats were determined by flow cytometry.GSH-Px activity and MDA level in the rats' pancreas were measured using biochemical methods.The insulin contents in serum and β cell insulin secret storage were tested by RIA and IHC,respectively.There was an increase in the percentages of IL-4 and IL-10 positive lymphocytes in the peripheral blood and spleen of the groups of rats supplemented with various combinations of micronutrients(p<0.01 and p<0.05,respectively);the blood glucose concentration decreased(p<0.05);both the functional β cell in islets and the insulin content in pancreatic tissue increased(p<0.05 and p<0.01);the GSH-Px activity and MDA level of pancreas in the rats enhanced and decreased respectively(p<0.01 and p<0.05).The results suggest that micronutrients may alleviate the islet lesions by upregulating the expressions of IL-4 and IL-10 and lowering oxidative stress in diabetic rats.  相似文献   

8.
The glucocorticoid receptor (GCR) of the cytosol of liver and brain was studied by radioligand binding assay, using [~3H] dexamethasone (Dex) as the ligand in lethally and nonlethally scalded rats. As compared with controls, the binding capacity (R_0) was decreased and the apparent K_d of [~3H] Dex specific binding was increased in both scalded groups. In the lethal group, the R_u is much lower than that in the nonlethal group. In order to determine whether the decrease of R_0 was due to the translocation of [~3H] Dex-GCR complex into the cell nuclei, the [~3H] corticosterone (B) specific binding of the hepatic nuclei was measured by the exchange assay. There was no significant difference between the control and scalded groups. The possible mechanisms and the clinical significance of these changes were discussed.  相似文献   

9.
In the search of novel neuroprotective agents with higher potency than our previously identified antiischemic stroke drug candidate 1, a series of novel dicarbonyl piperazine derivatives were synthesized and evaluated on their neuroprotective activity via oxygen–glucose deprivation test in the neuron-like PC12 cells, hypoxia tolerance model in mice and focal cerebral ischemia model in rats. The result obtained indicated that compounds 7f, 7k and 7o, exhibited neuroprotective activity. Particularly,compound 7o containing 2,5-dimethylpiperazin moiety, showed prolonged life time of mice and reduced cerebral infarction of rats, which provided a potential candidate for the development of neuroprotective agents.  相似文献   

10.
We evaluated the biocompatibility of a dimethylpolysiloxane-coated micro-device which had been designed for monitoring real-time bladder volume in previous studies.The extract assay with dimethylpolysiloxane which had been used for coating the micro-device to measure the bladder volume was performed as an in vitro cytotoxicity test.For in vivo biocompatibility testing,the inflammatory responses around the implantation site of the micro-device in subcutaneous tissue of rat were assessed by light microscope with H&E stain and fluorescence microscope with ED1 stain and von Willebrand factor stain.The averages of cell viability in dimethylpolysiloxane group were 84.6%and 82.3%at 24 h and 72 h incubation, respectively.The qualitative evaluations with light and fluorescence microscope revealed that the inflammatory changes peaked during 2 weeks but almost disappeared at 4 weeks after implantation of devices.The quantitative evaluations for granulation layer formation and neovascularization showed that the thickness of the layer in dimethylpolysiloxane group peaked during 2 weeks but it came to be stabilized at 4 weeks as thin as at 2 weeks in control group,and the frequency of neovascularization was higher in dimethylpolysiloxane group than in control group but it was not increased with time.The dimethylpolysiloxane-coated micro-device is thought be a reliable bio-medical device.  相似文献   

11.
The effects of the ingestion of corn peptides with a low molecular weight(LMCP) prepared from zein on some plasma free amino acid concentrations in rats that had taken ethanol were investigated. LMCP(1.0g/kg body weight) in 15~ ethanol(10 mL/kg body weight) was given to Wister rats by intragastrical administration. The amino acid analysis showed that the concentrations of aianine, leucine, and proline in the plasma reached their maximum levels at 30 min for the LMCP-intake group. They are 582.39, 99.60 and 272.51 μg/L, respectively. But in the control group, the plasma free amino acid levels were not changed obviously.Therefore, LMCP could cause an increase in concentration of some free amino acids such as alanine, leucine and proline etc. in plasma of the rats that have taken ethanol.  相似文献   

12.
In order to create a functionalized biodegradable polymer for vascular tissue engineering application,poly(DL- lactide-co-RS-β-malic acid)(PDLLMAc)was synthesized.PDLLMAc was obtained after hydrogenolysis of poly(DL- lactide-co-RS-β-benzyl malolactonate)(PDLLMA),which was from the ring-opening polymerization of DL-lactide(DLLA) and RS-β-benzyl malolactonate(MA)using stannous octoate as catalyst.The copolymers were characterized by ~1H-NMR, FTIR,GPC and DSC.The tensile strength and water uptake of the copolymers were measured.In copolymerization,the proportion of MA in the derived copolymers was lower than that in the feeding dose,a consequence of its lower reactivity. The molecular weight of the copolymers decreased with increasing MA content.The protective benzyl groups were completely removed in hydrogenolysis.The glass transition temperature(T_g)of the protected copolymers decreased with increasing MA content.The mechanical strength test showed that the tensile strength of PDLLMA decreased while elongation increased with MA content increasing,and the tensile strength increased and elongation decreased with increasing malic acid content in PDLLMAc for the formation of hydrogen bonding.The water uptake showed that more hydrophilic malic acid adsorbed more water in PDLLMAc.In order to test the reactivity of functional pendant groups,bioactive RGD peptide was immobilized on the functionalized polymer film surface and smooth muscle cells(SMCs)were cultured on it. The results showed that the functionalized copolymer was biocompatible and could be potentially applied in vascular tissue engineering.  相似文献   

13.
A high sensitive method based on liquid chromatography tandem mass spectrometry(LC-MS/MS) was developed and validated for the study of permeability of danshensu(DS) and paeoniflorin(PF) in Caco-2 intestinal absorption model. The DS and PF were extracted from cell culture by vacuum-lyophilizing and then separated on a Zorbax Stable Bond C18 column with 0.1% acetic acid aqueous solution and methanol as mobile phase. Detection was carried out by negative electrospray ionization(ESI ) with selected reaction monitoring(SRM) mode. The apparent permeability coefficients(Papp) of DS and PF in Caco-2 cell medium were calculated and the effects of verapamil on the coefficients Papp of the two test compounds were also illustrated. The permeability of PF was much better than that of DS when the two compounds were administrated individually. Co-administration of DS and PF led to the decrease of the transport from apical side to basolateral side for both the compounds. However, the transport in the contrary direction were accelerated. It was also observed that verapamil could accelerate the transport of the test compounds from apical side to basolateral side. However, the absorption-enhanced effect of verapamil was attenuated when DS and PF were co-administrated. These observations suggest that both passive diffusion and active efflux involved in P-gp would effect the passage of DS and PF across Caco-2 cell monolayer. At the same time, the co-administration of DS and PF to an alteration of transport behavior, which suggests that the interaction must be taken into account when ‘n-in-one' samples were used in Caco-2 intestinal model.  相似文献   

14.
Fumed silica/bisphenol A dicyanate ester(BADCy)nanocomposites were prepared by introducing different contents of nano-sized fumed SiO2 into the BADCy matrix.Two different average primary particle diameters of 12 and 40 nm were chosen.Dibutyltindilaurate(DBTDL)catalyst was chosen to catalyze the cyanate ester group into triazine group via cyclotrimerization reaction.The SEM micrographs indicated that the fumed SiO2 particles were homogeneously dispersed in the poly(bisphenol A dicyanate)matrix by means of ultrasonic treatment and the addition of a coupling agent. The FTIR spectroscopy shows that,not only DBTDL catalyzes the polymerization reaction but also-OH groups of the SiO2 particles surface help the catalyst for the complete polymerization of BADCy monomer.The thermal stability of the cured BADCy can be improved by adequate addition of fumed SiO2.A slight increase in the dielectric constant and dielectric loss values were identified by testing the dielectric properties of the prepared nanocomposite samples.By increasing the SiO2 content,there was a slight increasing in the thermal conductivity values of the tested samples.The obtained results proved that the fumed silica/BADCy nanocomposites had good thermal and dielectrical properties and can be used in many applications such as in the thermal insulation field.  相似文献   

15.
The authors chose specimens from nine normal prostate tissues(NP group), 15 benign prostate hyperplasia(BPH) prostates(BPH group), and 35 BPH prostates that had been treated'with ^90Sr/^90Y Prostatic Hyperplasia Applicator(exposure group). The expressions of bcl-2 and bax in stroma and epithelia of prostate tissues were demonstrated by means of immunohistochemical staining, and the staining positive rate was semiquantatively determined, so as to observe the expression of bcl-2 and bax genes in the prostate tissues of normal individuals and BPH patients, before and after fl radiation, and to evaluate the influence of fl radiation on bcl-2 and bax expressions. The expressions of gene bcl-2 in the prostate epithelia of NP and BPH are significantly higher than those in the prostate stroma(P〈0.01). However, the expressions of bcl-2 in the prostate epithelia and stroma of the BPH group are obviously higher than those in the NP group(P〈0.01). The expression of gene bax in the prostate epithelia of the NP group is higher than that in the BPH group(P〈0.05). However, bcl-2 expressions in the prostate epithelia and stroma of the BPH group are significantly higher than the bax expressions(P〈0.01). Compared with those of the NP group, the expressions of bcl-2 in the prostate epithelia and stroma of the exposure group decrease remarkably, even as the expressions of the bax notably increase(P〈0.01). Thus, the administration of β radiation can remarkably affect bcl-2 and bax gene expressions, to regulate cell apoptosis, in the prostate tissues of BPH.  相似文献   

16.
A selenium-modified hyaluronic acid(HA) compound(SeHA) was synthesized as a mimic of glutathione peroxidase(GPX). IR and NMR spectra of SeHA predict that the --CH2OH group of the N-acetyl-D-glucosamine in HA was modified by group --Sell. There are averagely 152 --Sell groups in one SeHA molecule. The GPX activities are 103.88, 32. 15 and 152. 71 U/μmol, respectively, when the substrates were H2O2, BuOOH and CuOOH. Ping-pong mechanism was observed in the steady-state kinetic studies of the reactive oxygen species(ROS) consuming reaction. Result of reactions of SeHA with free radical capturer 2,6-di-tert-butyl-4-methylphenol(BHT) shows that the catalysis is based on a non-free radical-mechanism and the SeHA can not be inhibited by iodoacetate, an enzyme inhibitor.  相似文献   

17.
Ginsenosides Rgl, Re, Rb1, Rc, Rb2, Rb3, and Rd in different parts of the American ginseng plant were investigated. The extraction process was a pressurized microwave-assisted extraction(PMAE). The seven ginsenosides were separated and determined by high-performance liquid chromatography(HPLC) with a ultraviolet(UV) detector, at 203 nm. The experiment results showed significant variations in the individual ginsenoside contents of the American ginseng in different parts and ages of the plant. The results demonstrated that the leaves, root hairs, and rhizomes of Panax quinquefolius L. contained higher ginsenoside contents, followed by the main roots and stems. The leaves contained dramatically higher levels of ginsenoside Rg1 Rb3, and Rd than the other four parts. Higher contents of Rb1 and Re were present in the main roots, root hairs, and rhizomes. The amount of ginsenoside content in the stems was the lowest. The total content of the seven ginsenosides in main roots, root hairs and rhizomes increased with the age of the plant. In contrast, the ginsenoside contents in the leaves and stems decreased with a year of growth.  相似文献   

18.
吴飞鹏 《高分子科学》2011,29(3):352-359
A series of cationic surfmers with benzyl groups(QARBCs)with different R groups on the benzene ring were synthesized and characterized by IR,1H-NMR,13C-NMR.The aggregation of QARBCs was studied by the steady-state fluorescence technique.It turned out that QARBCs had surface activity and their critical micelle concentration(CMC)values varied in the range of 10-2—10-3mol/L with slight increase with temperature.The copolymerization of acrylamide(M1)and QARBCs(M2)was studied below and above CMC,their reactivity ratios were determined by the Finemann-Ross method.It was found that below CMC,copolymerization took place in a homogeneous system and reactivity ratios of acrylamide and QARBCs were less than 1;while above CMC,reactivity ratios of QARBCs were greater than 1.The copolymerization mechanism of QARBC was observed to be similar to that of micellar polymerization.QARBCs tended to homopolymerization,which gave rise to micro-blocky sequences in the polymer backbone.The Q and e values of QARBCs were calculated according to the Alfrey-Price equation by using r1(AM)and r2(qarBC).Samples of poly(AM-co-QARBC) were prepared above and below CMC and their hydrophobic associations were studied by the steady-state fluorescence spectra and 2D NOESY spectra,and their critical associating concentrations(CAC)were estimated.The results showed that samples of poly(AM-co-QARBC)prepared above CMC had stronger hydrophobic association in aqueous solution than those prepared below CMC.  相似文献   

19.
孙玉敬  叶兴乾  庞杰  李俊  吕元 《结构化学》2009,28(4):439-444
The interactions between konjac glucomannan and carrageenan were studied with the method of molecular dynamics simulation. Part representative structure segments of KGM and two unit structures of κ-carrageenan (Fig. 2) were used as mode, and the force-field was AMBER2. The stability and sites of konjac glucomannan/carrageenan interactions in water were researched at 373 K with the following results: the potential energy (EPOT) of the mixed gel was dropped, while those of single-konjac glucomannan gel and single carrageenan were increased. The surface area (SA) of KGM in the mixed system was decreased to 1002.2A^°^2, and that of carrageenan to 800.9 A^°^2. The variations of two parameters showed that the stability of compound gel konjac glucomannan/carrageenan was improved, which is consistent with the previous studies. The sites of interactions in the mixed gel were the -OH groups on C(2), C(4) and C(6), the acetyl group in KGM mannose, and the -OH group on C(6) in carrageenan. The hydrogen bond was formed directly or indirectly by the bridge of waters.  相似文献   

20.
Macromolecular ligands with liver-targeting group (pyridoxamine, PM) PHEA-DTPA-PM and PAEA-DTPA-PM were prepared by the incorporation of different amount of diethylenetria-minepentaacetic acid monopyridoxamine group (DTPA-PM) into poly-cc, p-[N-(2-hydroxyethyl)-L-aspartamide] (PHEA) and poly-α, β-[N-(2-aminoethyl)-L-aspartamide] (PAEA). The macromolecular ligands thus obtained were further complexed with gadolinium chloride to give macromolecular MRI contrast agents with different Gd(Ⅲ) contents. These macromolecular ligands and their gadolinium complexes were characterized by 1H NMR, 1R, UV and elementary analysis. Relaxivity studies showed that these polyaspartamide gadolinium complexes possess higher relaxation effectiveness than that of the clinically used Gd-DTPA. Magnetic resonance imaging of the liver in rats and experimental data of biodistribution in mice indicate that these macromolecular MRI contrast agents containing pyridoxamine exhibit liver-targeting property.  相似文献   

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