A water soluble crude extract prepared from Ornithogalum caudatum Ait. (OCA) showing a high immunomodulating activitiy was isolated and characterized by virtue of gel filtration and column chromatography. The pre...A water soluble crude extract prepared from Ornithogalum caudatum Ait. (OCA) showing a high immunomodulating activitiy was isolated and characterized by virtue of gel filtration and column chromatography. The presence of the monosaccharides has been established by the chemical analysis. The quantitative analysis of the alditol acetate derivatives of them showed the ratios of the monosaccharides analyzed by means of GC respectively. The concentrations of protein(280 nm) and carbohydrate(496 nm) were detected respectively. The information of the molecular weight from the pure polysaccharide was obtained by several standard Dextrans from the Sephadex chromatography.展开更多
1 INTRODUCTION Wood-rotting fungi have been intensively studied in China (Dai & Niemel? 2002; Dai et al. 2003, 2004a, 2004b; Dai & Penttil? 2006), and some new species and new records were found
A novel 5-fluorouracil salt of 12-silicatungstic acid was synthesized and characterized by means of elemental analysis, IR, 1H NMR and 183W NMR spectra. The antitumor activity and toxicity of the complex have been eva...A novel 5-fluorouracil salt of 12-silicatungstic acid was synthesized and characterized by means of elemental analysis, IR, 1H NMR and 183W NMR spectra. The antitumor activity and toxicity of the complex have been evaluated both in vitro and in vivo.展开更多
ThefecC gene encoding a putative iron (III) dicitrate transporter was cloned from nitrogen-fixing cyanobacteriumAnabaena sp. PCC 7120, and inactivated. The mutant grows normally in medium with NO 3 ? , NH 4 + or witho...ThefecC gene encoding a putative iron (III) dicitrate transporter was cloned from nitrogen-fixing cyanobacteriumAnabaena sp. PCC 7120, and inactivated. The mutant grows normally in medium with NO 3 ? , NH 4 + or without combined nitrogen. But in iron-deficient medium, the mutant grows slowly. Photosynthetic properties were compared between the mutant and the wildtype strain, the content of photosynthetic pigments in the mutant is lower than that of the wild-type. The results of RT-PCR experiments show that thefecC gene is expressed under iron-deficient conditions, but is not expressed under iron-replete conditions. These results revealed thatfecC gene product is required for optimal growth under iron-deficient conditions inAnabaena sp. PCC 7120. Key words Anabaena sp. PCC 7120 - fecC - iron deficiency - photosynthetic properties - expression CLC number Q 933 Foundation item: Supported by the National Natural Sciences Foundation of China (30070154), the Frontier Science Projects Program of the Institute of Hydrobiology, the Chinese Academy of Sciences (220316), State Key Project on Cyanobacterial Bloom Control in Lake Dianchi (K99-05-35-01)Biography: XU Wen-liang (1974-), male, Ph. D, research direction: molecular genetics of cyanobacteria.展开更多
Polyoxometallates Co(en) 3PMo 12O 40·8H 2O(+,-)[abbreviated as PMo 12-Co(+,-)], nanoparticles were synthesized by the chemical precipitation reaction at room temperature for the first time. They were c...Polyoxometallates Co(en) 3PMo 12O 40·8H 2O(+,-)[abbreviated as PMo 12-Co(+,-)], nanoparticles were synthesized by the chemical precipitation reaction at room temperature for the first time. They were characterized by means of elemental analyses, IR spectrometry and X-ray diffraction. The images of scanning electron microscopy(SEM) and the results of calculation by using the Scherrer equation for the line widths of the XRD patterns were used to estimate the average particle size of the powder products, which was 40 nm. The results show that the nanoparticle size was affected by starting materials′ concentrations. The particles had a small size and a narrow distribution, when the concentrations of H 3PMo 12O 40·24H 2O and Co(en) 3I 3·H 2O were around 1.7×10 -4 and 1.0×10 -3 mol/L, respectively. When the concentration was increased, there was no significant increase in the particle size, but more polydisperse Co(en) 3(PMo 12O 40) (+, -) were obtained. In poly(ethylene glycol)(PEG) with an average molecular weight(M W) of 600 g/mol and containing LiClO 4[n(O)/n(Li)=100∶1] as the supporting electrolyte, the conductivity of the composite system increases upon the addition of PMo 12-Co(+ or -) nanoparticles, which was measured by the a.c. impedance technique. The interactions among PEG, LiClO 4, PMo 12, and Co can be used to explain that the PMo 12-Co(+ or -) nanoparticles could promote the conductivity of the PEG-LiClO4-PMo12-Co system.展开更多
The white organic light emitting device (OLED) with single-structure using a polymer blend as the light emitting layer is fabricated.Heat treatment is used to control the ratio between the intensities of main electrol...The white organic light emitting device (OLED) with single-structure using a polymer blend as the light emitting layer is fabricated.Heat treatment is used to control the ratio between the intensities of main electroluminescent spectral peaks.The electroluminescent spectrum of our device is quite similar to that of white inorganic LED produced by Nichia Corporation after being annealed,and its turn-on voltage can be decreased by 1 V.展开更多
A novel adenine(Ade) salt of 12-phosphotungstic acid was synthesized and characterized by elemental analyses,IR, 1H NMR,CV and single crystal X-ray diffraction. The compound crystallized in a triclinic system with...A novel adenine(Ade) salt of 12-phosphotungstic acid was synthesized and characterized by elemental analyses,IR, 1H NMR,CV and single crystal X-ray diffraction. The compound crystallized in a triclinic system with a space group P 1 and a =1.3108(3) nm, b =1.3515(3) nm,c =1.3870(3) nm, V =2.0217(7) nm 3,Z =1,R _1=0.0391,wR _2=0.0959. The structure unit of the complex was constructed from [HPW_ 12 ·O_ 40 ] -,(C_5H_6N_5) + and C_3H_7NO,which further extends to form a novel three-dimensional host-guest network via hydrogen-bonding interactions. The anti-tumor activity of the compound was examined in two human tumor cell lines in vitro .展开更多
The present study was carried out on rat heart to in situ determine the myocardial toxicity of moniliformin, a synthesized compound, originally isolated from mouldy corn and soil samples in the Keshan disease prevalen...The present study was carried out on rat heart to in situ determine the myocardial toxicity of moniliformin, a synthesized compound, originally isolated from mouldy corn and soil samples in the Keshan disease prevalent area in China. Perfusion of moniliformin 10~(-7 mol/liter in isolated heart decreased myocardial contractile force by 52±17%. Intravenous injection of moniliformin at 1/6 and 1/4 LD50 markedly inhibited cardiac hemodynamic variables relative to myocardial contractile function. Particularly, it decreased ±LV dP/dt max by 52± 6%, and induced ventricular arrhythmia. These data indicate that moniliformin is toxic to mammalian heart and might be an important factor relative to Keshan disease.展开更多
The authors show the regularity of weak solutions for some typical quasi-linear elliptic systems governed by two p-Laplacian operators. The weak solutions of the following problem with lack of compactness are proved t...The authors show the regularity of weak solutions for some typical quasi-linear elliptic systems governed by two p-Laplacian operators. The weak solutions of the following problem with lack of compactness are proved to be regular when a(x) and α, β,p,q satisfy some conditions:-△qv + a(x)|u|α+1|v|β-1u = |v|q*-2u, x ∈Ω,u(x) = v(.x) = 0, x ∈ ()Ω,where Ω() RN (N ≥ 3) is a smooth bounded domain.展开更多
文摘A water soluble crude extract prepared from Ornithogalum caudatum Ait. (OCA) showing a high immunomodulating activitiy was isolated and characterized by virtue of gel filtration and column chromatography. The presence of the monosaccharides has been established by the chemical analysis. The quantitative analysis of the alditol acetate derivatives of them showed the ratios of the monosaccharides analyzed by means of GC respectively. The concentrations of protein(280 nm) and carbohydrate(496 nm) were detected respectively. The information of the molecular weight from the pure polysaccharide was obtained by several standard Dextrans from the Sephadex chromatography.
基金Supported by National Nature Science Foundation of China （No. 30670009）We thank Drs. YUAN Hai-Sheng and WANG Han-Chen （Shenyang, China） for companion in the field trip.
文摘1 INTRODUCTION Wood-rotting fungi have been intensively studied in China (Dai & Niemel? 2002; Dai et al. 2003, 2004a, 2004b; Dai & Penttil? 2006), and some new species and new records were found
文摘A novel 5-fluorouracil salt of 12-silicatungstic acid was synthesized and characterized by means of elemental analysis, IR, 1H NMR and 183W NMR spectra. The antitumor activity and toxicity of the complex have been evaluated both in vitro and in vivo.
文摘ThefecC gene encoding a putative iron (III) dicitrate transporter was cloned from nitrogen-fixing cyanobacteriumAnabaena sp. PCC 7120, and inactivated. The mutant grows normally in medium with NO 3 ? , NH 4 + or without combined nitrogen. But in iron-deficient medium, the mutant grows slowly. Photosynthetic properties were compared between the mutant and the wildtype strain, the content of photosynthetic pigments in the mutant is lower than that of the wild-type. The results of RT-PCR experiments show that thefecC gene is expressed under iron-deficient conditions, but is not expressed under iron-replete conditions. These results revealed thatfecC gene product is required for optimal growth under iron-deficient conditions inAnabaena sp. PCC 7120. Key words Anabaena sp. PCC 7120 - fecC - iron deficiency - photosynthetic properties - expression CLC number Q 933 Foundation item: Supported by the National Natural Sciences Foundation of China (30070154), the Frontier Science Projects Program of the Institute of Hydrobiology, the Chinese Academy of Sciences (220316), State Key Project on Cyanobacterial Bloom Control in Lake Dianchi (K99-05-35-01)Biography: XU Wen-liang (1974-), male, Ph. D, research direction: molecular genetics of cyanobacteria.
基金Supported by the National Natural Science Foundation of China(No.2 0 3710 0 7)
文摘Polyoxometallates Co(en) 3PMo 12O 40·8H 2O(+,-)[abbreviated as PMo 12-Co(+,-)], nanoparticles were synthesized by the chemical precipitation reaction at room temperature for the first time. They were characterized by means of elemental analyses, IR spectrometry and X-ray diffraction. The images of scanning electron microscopy(SEM) and the results of calculation by using the Scherrer equation for the line widths of the XRD patterns were used to estimate the average particle size of the powder products, which was 40 nm. The results show that the nanoparticle size was affected by starting materials′ concentrations. The particles had a small size and a narrow distribution, when the concentrations of H 3PMo 12O 40·24H 2O and Co(en) 3I 3·H 2O were around 1.7×10 -4 and 1.0×10 -3 mol/L, respectively. When the concentration was increased, there was no significant increase in the particle size, but more polydisperse Co(en) 3(PMo 12O 40) (+, -) were obtained. In poly(ethylene glycol)(PEG) with an average molecular weight(M W) of 600 g/mol and containing LiClO 4[n(O)/n(Li)=100∶1] as the supporting electrolyte, the conductivity of the composite system increases upon the addition of PMo 12-Co(+ or -) nanoparticles, which was measured by the a.c. impedance technique. The interactions among PEG, LiClO 4, PMo 12, and Co can be used to explain that the PMo 12-Co(+ or -) nanoparticles could promote the conductivity of the PEG-LiClO4-PMo12-Co system.
文摘The white organic light emitting device (OLED) with single-structure using a polymer blend as the light emitting layer is fabricated.Heat treatment is used to control the ratio between the intensities of main electroluminescent spectral peaks.The electroluminescent spectrum of our device is quite similar to that of white inorganic LED produced by Nichia Corporation after being annealed,and its turn-on voltage can be decreased by 1 V.
文摘A novel adenine(Ade) salt of 12-phosphotungstic acid was synthesized and characterized by elemental analyses,IR, 1H NMR,CV and single crystal X-ray diffraction. The compound crystallized in a triclinic system with a space group P 1 and a =1.3108(3) nm, b =1.3515(3) nm,c =1.3870(3) nm, V =2.0217(7) nm 3,Z =1,R _1=0.0391,wR _2=0.0959. The structure unit of the complex was constructed from [HPW_ 12 ·O_ 40 ] -,(C_5H_6N_5) + and C_3H_7NO,which further extends to form a novel three-dimensional host-guest network via hydrogen-bonding interactions. The anti-tumor activity of the compound was examined in two human tumor cell lines in vitro .
文摘The present study was carried out on rat heart to in situ determine the myocardial toxicity of moniliformin, a synthesized compound, originally isolated from mouldy corn and soil samples in the Keshan disease prevalent area in China. Perfusion of moniliformin 10~(-7 mol/liter in isolated heart decreased myocardial contractile force by 52±17%. Intravenous injection of moniliformin at 1/6 and 1/4 LD50 markedly inhibited cardiac hemodynamic variables relative to myocardial contractile function. Particularly, it decreased ±LV dP/dt max by 52± 6%, and induced ventricular arrhythmia. These data indicate that moniliformin is toxic to mammalian heart and might be an important factor relative to Keshan disease.
基金Project supported by the National Natural Science Foundation of China (No.10271077).
文摘The authors show the regularity of weak solutions for some typical quasi-linear elliptic systems governed by two p-Laplacian operators. The weak solutions of the following problem with lack of compactness are proved to be regular when a(x) and α, β,p,q satisfy some conditions:-△qv + a(x)|u|α+1|v|β-1u = |v|q*-2u, x ∈Ω,u(x) = v(.x) = 0, x ∈ ()Ω,where Ω() RN (N ≥ 3) is a smooth bounded domain.
