AIM: To investigate the gastroprotective effect and mechanism of amtolmetin guacyl (AMG, MED15) in mice.METHODS: Male and female Kunming strain mice,weighing 18-22 g, were utilized in the experiment. Normal or ethanol...AIM: To investigate the gastroprotective effect and mechanism of amtolmetin guacyl (AMG, MED15) in mice.METHODS: Male and female Kunming strain mice,weighing 18-22 g, were utilized in the experiment. Normal or ethanol-induced gastric mucosal damage models in mice were successfully established to investigate the gastroprotective effect and mechanism of AMG. In the experiment of gastric mucosal damage after repeated treatment with AMG, the mice were randomly divided into 5 groups: normal group, 3 AMG groups receiving (75, 150 and 300 mg/kg), and tolmetin group receiving 90 mg/kg.The mice were randomly divided into 6 groups as follows:normal group, model group, AMG groups with doses of 75, 150 and 300 mg/kg, respectively, and tolmetin group with a dose of 90 mg/kg in ethanol-induced gastric mucosal damage experiment. The severity of gastric mucosal lesions was scored from 0 to 5. Gastric tissue sections were stained with hematoxylin and eosin (HE) and examined under light microscopy. Also gastric tissue sections were stained with uranyl acetate and lead citrate, and examined under electron microscopy. In addition, nitric oxide (NO) and malondialdehyde (MDA) contents, and nitric oxide synthase (NOS) and superoxide dismutase (SOD) activities in the stomach tissue homogenates were measured by biochemical methods.RESULTS: Repeated treatment with AMG (75, 150 and3 00 mg/kg) for 7 d did not induce any appreciable mucosal damage, and the average score was not significantly different from that of normal mice. In contrast, tolmetin (90 mg/kg) produced significant gastric mucosal lesions compared with the normal group (P<0.01). AMG (75, 150 and 300 mg/kg) significantly reduced the severity of gastric lesions induced by ethanol in a dose-dependent manner as compared with the model group (P<0.05, AMG 75 and 150 mg/kg vs model; P<0.01, AMG 300 mg/kg vs model).Light and electron microscopy revealed that AMG (150 and 300 mg/kg) induced minimal changes in the surface epithelium layer, without vascular congestion or leucocyte adhere展开更多
A novel fluorene-based conjugated copolymer containing cyclobutenedione unit was synthesized by Suzuki reaction. Its structure and properties were characterized by FTIR, 1HNMR, elemental analysis, PL spectroscopy, DSC...A novel fluorene-based conjugated copolymer containing cyclobutenedione unit was synthesized by Suzuki reaction. Its structure and properties were characterized by FTIR, 1HNMR, elemental analysis, PL spectroscopy, DSC, TGA and cyclic voltammetry. The resulting polymer shows strong yellow PL emission (561 nm) and good solubility in polar aprotic solvents, i.e. THF, DMF, DMAC, DMSO, etc. DSC and TGA studies reveal that the novel polymer possesses excellent thermal stability with high glass transition temperature of 127℃ and onset decomposition temperature of 411℃. Cyclic voltammetry measurement demonstrated that the polymer has both hole and electron-transporting property.展开更多
The dipole resonances of gold nanocages were investigated theoretically using finite difference time domain method.The results show that field enhancement is obtained at the walls of the gold nanocages.It is believed ...The dipole resonances of gold nanocages were investigated theoretically using finite difference time domain method.The results show that field enhancement is obtained at the walls of the gold nanocages.It is believed that the effect can cause a strong optical nonlinear property.To test the hypothesis,nonlinear absorption was investigated using a broadband 5 ns Z scan.It was found that at low intensities the sample shows saturable absorption(SA),while at higher intensities a switch from SA to reverse SA occurs.Moreover,the nonlinear absorption of the sample is sensitively wavelength-dependent,and,in the resonant region,saturation intensity is the largest.展开更多
In the framework of relativistic quantum hadron dynamical theory,under semiclassical approximation and taking the vacuum fluctuation into account,a relativistic Vlasov equation(RVE)has been derived.Using RVE and consi...In the framework of relativistic quantum hadron dynamical theory,under semiclassical approximation and taking the vacuum fluctuation into account,a relativistic Vlasov equation(RVE)has been derived.Using RVE and considering other relativistic effects,we have studied the isovector dipole giant resonances built on ground state in spherical nuclei.The main results shown that the resonance energies for each multipole are larger than those obtained from the non-relativistic classical Vlasov approach.But by means of choosing a reasonable symmetry potential as 100MeV,the relativistic results can fit the experimental results very well.展开更多
文摘AIM: To investigate the gastroprotective effect and mechanism of amtolmetin guacyl (AMG, MED15) in mice.METHODS: Male and female Kunming strain mice,weighing 18-22 g, were utilized in the experiment. Normal or ethanol-induced gastric mucosal damage models in mice were successfully established to investigate the gastroprotective effect and mechanism of AMG. In the experiment of gastric mucosal damage after repeated treatment with AMG, the mice were randomly divided into 5 groups: normal group, 3 AMG groups receiving (75, 150 and 300 mg/kg), and tolmetin group receiving 90 mg/kg.The mice were randomly divided into 6 groups as follows:normal group, model group, AMG groups with doses of 75, 150 and 300 mg/kg, respectively, and tolmetin group with a dose of 90 mg/kg in ethanol-induced gastric mucosal damage experiment. The severity of gastric mucosal lesions was scored from 0 to 5. Gastric tissue sections were stained with hematoxylin and eosin (HE) and examined under light microscopy. Also gastric tissue sections were stained with uranyl acetate and lead citrate, and examined under electron microscopy. In addition, nitric oxide (NO) and malondialdehyde (MDA) contents, and nitric oxide synthase (NOS) and superoxide dismutase (SOD) activities in the stomach tissue homogenates were measured by biochemical methods.RESULTS: Repeated treatment with AMG (75, 150 and3 00 mg/kg) for 7 d did not induce any appreciable mucosal damage, and the average score was not significantly different from that of normal mice. In contrast, tolmetin (90 mg/kg) produced significant gastric mucosal lesions compared with the normal group (P<0.01). AMG (75, 150 and 300 mg/kg) significantly reduced the severity of gastric lesions induced by ethanol in a dose-dependent manner as compared with the model group (P<0.05, AMG 75 and 150 mg/kg vs model; P<0.01, AMG 300 mg/kg vs model).Light and electron microscopy revealed that AMG (150 and 300 mg/kg) induced minimal changes in the surface epithelium layer, without vascular congestion or leucocyte adhere
文摘A novel fluorene-based conjugated copolymer containing cyclobutenedione unit was synthesized by Suzuki reaction. Its structure and properties were characterized by FTIR, 1HNMR, elemental analysis, PL spectroscopy, DSC, TGA and cyclic voltammetry. The resulting polymer shows strong yellow PL emission (561 nm) and good solubility in polar aprotic solvents, i.e. THF, DMF, DMAC, DMSO, etc. DSC and TGA studies reveal that the novel polymer possesses excellent thermal stability with high glass transition temperature of 127℃ and onset decomposition temperature of 411℃. Cyclic voltammetry measurement demonstrated that the polymer has both hole and electron-transporting property.
基金supported by the Science and Technology Project of Heilongjiang Education Department(No.11531283).
文摘The dipole resonances of gold nanocages were investigated theoretically using finite difference time domain method.The results show that field enhancement is obtained at the walls of the gold nanocages.It is believed that the effect can cause a strong optical nonlinear property.To test the hypothesis,nonlinear absorption was investigated using a broadband 5 ns Z scan.It was found that at low intensities the sample shows saturable absorption(SA),while at higher intensities a switch from SA to reverse SA occurs.Moreover,the nonlinear absorption of the sample is sensitively wavelength-dependent,and,in the resonant region,saturation intensity is the largest.
基金Supported in part by the National Nature Science Foundation of China under Contract No.19275058the Grant LWTZ-1298 of Chincsc Academy of Science.
文摘In the framework of relativistic quantum hadron dynamical theory,under semiclassical approximation and taking the vacuum fluctuation into account,a relativistic Vlasov equation(RVE)has been derived.Using RVE and considering other relativistic effects,we have studied the isovector dipole giant resonances built on ground state in spherical nuclei.The main results shown that the resonance energies for each multipole are larger than those obtained from the non-relativistic classical Vlasov approach.But by means of choosing a reasonable symmetry potential as 100MeV,the relativistic results can fit the experimental results very well.
