A azoreductase gene with 537 bp was obtained by PCR amplification from Rhodobacter sphaeroides AS1 1737 The enzyme, with a molecular weight of 18 7 kD, was efficiently expressed in Escherichia coli and its biodegr...A azoreductase gene with 537 bp was obtained by PCR amplification from Rhodobacter sphaeroides AS1 1737 The enzyme, with a molecular weight of 18 7 kD, was efficiently expressed in Escherichia coli and its biodegradation characteristics for azo dyes were investigated. Furthermore, the reaction kinetics and mechanism of azo dyes catalyzed by the genetically engineered azoreductase were studied in detail. The presence of a hydrazo-intermediate was identified, which provided a convincing evidence for the assumption that azo dyes were degraded via an incomplete reduction stage.展开更多
Since QuikSCAT is available in cloudy and rainy condition, its wind data are valuable in monitoring and real time forecasting the wind field, especially in sparse genesis regions of tropical cyclones. In order to unde...Since QuikSCAT is available in cloudy and rainy condition, its wind data are valuable in monitoring and real time forecasting the wind field, especially in sparse genesis regions of tropical cyclones. In order to understand and investigate the impact of QuikSCAT wind data, the three-dimensional variational data assimilation (3D-VAR) of scatterometric wind data has been employed for the tropical cyclone 'Vongfong' in the year 2002. The result shows that the QuikSCAT wind data have positive impact on the analysis and forecasting. But the positive impact is slight. The present results suggest that how to assimilate QuikSCAT wind data effectively is important and will be a challenge to meteorologists.展开更多
PAHs pollution in air of arterial roads was investigated from October 1998 to October 2001 in Hangzhou, China. The results showed that Σ10 PAHs was 13—36 μg/m3, among which, BaP, a strong carcinogenic kind ranged f...PAHs pollution in air of arterial roads was investigated from October 1998 to October 2001 in Hangzhou, China. The results showed that Σ10 PAHs was 13—36 μg/m3, among which, BaP, a strong carcinogenic kind ranged from 0.034 μg/m3 to 0.12 μg/m3. PAHs pollutions in four seasons were winter>autumn>spring-summer. The annual averages of ΣPAHs concentration were 25 μg/m3 for 1999, 28 μg/m3 for 2000, and 29 μg/m3 for 2001, respectively. Leaded gasoline was banned in December 1998 in Hangzhou, thus comparative measurements with PAHs in leaded and lead-free gasoline powered motor exhausts made it certain that the use of lead-free gasoline leaded to a heavier PAHs pollution in roadside air from December, 1998, in China, and ΣPAHs in air samples after the lead-banning were more than twice of that in samples before the action. For the large contribution of vehicle discharge to air pollution in roadside, further research was performed to suggest the factors influencing PAHs distribution in vehicle exhaust in order to control air pollution effectively. Compared to gasoline engines, emissions from diesel engines were less toxic, although they might produce more PAHs. Of the same vehicular and oil type, automobiles of longer mileages produced more toxic PAHs. PAHs distributions in the vehicular exhausts were related to the oil type. Large difference was found in the abundance of 3-, 5- and 6-ring PAHs between exhausts from gasoline and diesel oil engines. Diesel oil engines produced relative lighter PAHs such as NAPH, ACEN, FLUOR, while gasoline engines emitted heavier kinds such as BkF, IN and BP. The automobile produced more PAHs with the increase of mileage especially FLUR, PY, BaP, BP. Some significant ratios for traffic source in Hangzhou such as PHEN/AN, FLUR/PY, IN/BP were 0.50—4.3, 0.58—7.4, 0.51—1.5, respectively. A source fingerprint for vehicle exhausts of a mixture of vehicle and oil types in the city district for light-duty vehicle was the abundance of BaA, followed by NAPH, BP, IN. 4-ring PAHs such as FLUR, PY, BaA and CHRY were the most predominant kinds followed by 6-ring PAHs(BP, IN).展开更多
Fxperiments on the effect of soil amendment with rape (Brassica chinensis L.) seed cake, cotton (Gossypium hirsutum L.) seed or sesame (Sesamum indicum L.) seed cake on the growth of cucumber seedlings under a continu...Fxperiments on the effect of soil amendment with rape (Brassica chinensis L.) seed cake, cotton (Gossypium hirsutum L.) seed or sesame (Sesamum indicum L.) seed cake on the growth of cucumber seedlings under a continuous cropping system were conducted in a greenhouse environment. The results indicated that two applications of sesame seed cake (0.1 and 0.5 %, w/w) increased the growth of cucumber, but the rape oil cake showed a negative effect at a rate of 1.5% (w/w). The sesame seed cake was separated into four fractions (Ⅰ, Ⅱ, Ⅲ and Ⅳ) according to the polarity, and all four fractions had a positive effect on the growth of cucumbers under a continuous cropping system. Fraction number Ⅲ was isolated into 25 proportions by silicon column, and only oleic acid, palmitic acid and octadecanoic acid were identified in proportion 10 by GC-MS in which 93.3% was oleic acid and palmitic acid. The oleic acid had a significant and positive effect on cucumber growth under salt stress at the level 30 mmol and showed slight resistance to several pathogenic fungi.展开更多
目的 建立一种快速而特异的肺癌辅助诊断方法。方法 制备特异性识别肺癌细胞的鼠单克隆抗体，通过细胞免疫化学和ELISA方法检测抗体与痰液中脱落细胞的反应情况。结果 两种方法都显示，抗体2C25可选择性结合肺癌患者痰液中的脱落细胞，...目的 建立一种快速而特异的肺癌辅助诊断方法。方法 制备特异性识别肺癌细胞的鼠单克隆抗体，通过细胞免疫化学和ELISA方法检测抗体与痰液中脱落细胞的反应情况。结果 两种方法都显示，抗体2C25可选择性结合肺癌患者痰液中的脱落细胞，而不与肺炎患者和正常人痰液中的细胞发生反应。结论 抗体2C25在肺癌痰液免疫诊断中具有潜在的临床应用价值。Objective To develop a prompt and specific method for diagnosis of lung cancer.Methods A murine monoclonal antibody against lung cancer cells was developed and characterized with the techniques of ELISA,immunohistochemistry and immunocytochemical detection of sputum.Results The antibody selectively bound to lung cancer tissues and exfoliated cells in the sputum from the patients with lung canc-er, but did not bind to normal lung tissues and the cells in sputum either from the patients with pneumonia or from normal individu-als.Conclusion The antibody 2C25 has potential application for immunocytological detection of lung cancer cells in sputum.展开更多
文摘A azoreductase gene with 537 bp was obtained by PCR amplification from Rhodobacter sphaeroides AS1 1737 The enzyme, with a molecular weight of 18 7 kD, was efficiently expressed in Escherichia coli and its biodegradation characteristics for azo dyes were investigated. Furthermore, the reaction kinetics and mechanism of azo dyes catalyzed by the genetically engineered azoreductase were studied in detail. The presence of a hydrazo-intermediate was identified, which provided a convincing evidence for the assumption that azo dyes were degraded via an incomplete reduction stage.
文摘Since QuikSCAT is available in cloudy and rainy condition, its wind data are valuable in monitoring and real time forecasting the wind field, especially in sparse genesis regions of tropical cyclones. In order to understand and investigate the impact of QuikSCAT wind data, the three-dimensional variational data assimilation (3D-VAR) of scatterometric wind data has been employed for the tropical cyclone 'Vongfong' in the year 2002. The result shows that the QuikSCAT wind data have positive impact on the analysis and forecasting. But the positive impact is slight. The present results suggest that how to assimilate QuikSCAT wind data effectively is important and will be a challenge to meteorologists.
文摘PAHs pollution in air of arterial roads was investigated from October 1998 to October 2001 in Hangzhou, China. The results showed that Σ10 PAHs was 13—36 μg/m3, among which, BaP, a strong carcinogenic kind ranged from 0.034 μg/m3 to 0.12 μg/m3. PAHs pollutions in four seasons were winter>autumn>spring-summer. The annual averages of ΣPAHs concentration were 25 μg/m3 for 1999, 28 μg/m3 for 2000, and 29 μg/m3 for 2001, respectively. Leaded gasoline was banned in December 1998 in Hangzhou, thus comparative measurements with PAHs in leaded and lead-free gasoline powered motor exhausts made it certain that the use of lead-free gasoline leaded to a heavier PAHs pollution in roadside air from December, 1998, in China, and ΣPAHs in air samples after the lead-banning were more than twice of that in samples before the action. For the large contribution of vehicle discharge to air pollution in roadside, further research was performed to suggest the factors influencing PAHs distribution in vehicle exhaust in order to control air pollution effectively. Compared to gasoline engines, emissions from diesel engines were less toxic, although they might produce more PAHs. Of the same vehicular and oil type, automobiles of longer mileages produced more toxic PAHs. PAHs distributions in the vehicular exhausts were related to the oil type. Large difference was found in the abundance of 3-, 5- and 6-ring PAHs between exhausts from gasoline and diesel oil engines. Diesel oil engines produced relative lighter PAHs such as NAPH, ACEN, FLUOR, while gasoline engines emitted heavier kinds such as BkF, IN and BP. The automobile produced more PAHs with the increase of mileage especially FLUR, PY, BaP, BP. Some significant ratios for traffic source in Hangzhou such as PHEN/AN, FLUR/PY, IN/BP were 0.50—4.3, 0.58—7.4, 0.51—1.5, respectively. A source fingerprint for vehicle exhausts of a mixture of vehicle and oil types in the city district for light-duty vehicle was the abundance of BaA, followed by NAPH, BP, IN. 4-ring PAHs such as FLUR, PY, BaA and CHRY were the most predominant kinds followed by 6-ring PAHs(BP, IN).
文摘Fxperiments on the effect of soil amendment with rape (Brassica chinensis L.) seed cake, cotton (Gossypium hirsutum L.) seed or sesame (Sesamum indicum L.) seed cake on the growth of cucumber seedlings under a continuous cropping system were conducted in a greenhouse environment. The results indicated that two applications of sesame seed cake (0.1 and 0.5 %, w/w) increased the growth of cucumber, but the rape oil cake showed a negative effect at a rate of 1.5% (w/w). The sesame seed cake was separated into four fractions (Ⅰ, Ⅱ, Ⅲ and Ⅳ) according to the polarity, and all four fractions had a positive effect on the growth of cucumbers under a continuous cropping system. Fraction number Ⅲ was isolated into 25 proportions by silicon column, and only oleic acid, palmitic acid and octadecanoic acid were identified in proportion 10 by GC-MS in which 93.3% was oleic acid and palmitic acid. The oleic acid had a significant and positive effect on cucumber growth under salt stress at the level 30 mmol and showed slight resistance to several pathogenic fungi.
文摘目的 建立一种快速而特异的肺癌辅助诊断方法。方法 制备特异性识别肺癌细胞的鼠单克隆抗体，通过细胞免疫化学和ELISA方法检测抗体与痰液中脱落细胞的反应情况。结果 两种方法都显示，抗体2C25可选择性结合肺癌患者痰液中的脱落细胞，而不与肺炎患者和正常人痰液中的细胞发生反应。结论 抗体2C25在肺癌痰液免疫诊断中具有潜在的临床应用价值。Objective To develop a prompt and specific method for diagnosis of lung cancer.Methods A murine monoclonal antibody against lung cancer cells was developed and characterized with the techniques of ELISA,immunohistochemistry and immunocytochemical detection of sputum.Results The antibody selectively bound to lung cancer tissues and exfoliated cells in the sputum from the patients with lung canc-er, but did not bind to normal lung tissues and the cells in sputum either from the patients with pneumonia or from normal individu-als.Conclusion The antibody 2C25 has potential application for immunocytological detection of lung cancer cells in sputum.
