The use of synthetic anabolic steroid methyltestosterone (MT) as growth promoter is prohibited in China. Vali-dations of analytical methods for MT residue in food and the results obtained have become indispensable. Th...The use of synthetic anabolic steroid methyltestosterone (MT) as growth promoter is prohibited in China. Vali-dations of analytical methods for MT residue in food and the results obtained have become indispensable. The high perfor-mance liquid chromatography (HPLC) method for the detection of MT with liquid-liquid extraction by trichloromethane-methanol in carp muscle tissue was preliminarily validated with reference to the following parameters: recovery (accuracy)at the 1, 5 and 10mg kg-1 level, between-run and within-run CV values (repeatability, also called relative standard deviation(RSD)) and limit of detection. The recoveries were above 80% and the between-run and within-run CV values below 10%for muscle tissue. The limit of detection was 0.05 mg kg-1.展开更多
Under high-excitation irradiance conditions to induce fluorescence, the dependence of photobleaching of Coumarin 307 (C307) and acriflavine (ACF) laser dyes in liquid and solid phases have been studied. A cw LD la...Under high-excitation irradiance conditions to induce fluorescence, the dependence of photobleaching of Coumarin 307 (C307) and acriflavine (ACF) laser dyes in liquid and solid phases have been studied. A cw LD laser source of 1 mW and 407 nm wavelength was used as an exciting source. For one hour exposure time, it was found that the solid dye samples suffer photobleaching more than the liquid dye samples. This is because in liquid solutions the dye molecules can circulate during the irradiation, while the photobleaching is a serious problem when the dye is incorporated into solid matrix and cannot circulate.展开更多
Objective:To evaluate the impact of the diameter of SonoVue microbubbles on binding characteristics, including the adhesion rate and stability, of a new contrast agent targeted to choriocarcinoma cells(JARs) in vitro,...Objective:To evaluate the impact of the diameter of SonoVue microbubbles on binding characteristics, including the adhesion rate and stability, of a new contrast agent targeted to choriocarcinoma cells(JARs) in vitro, in order to establish a foundation to explore targeted ultrasound imaging for localization of tumor cell antigens and increase the early diagnostic rate for tumors.Methods:The objects were divided into three groups:the large microbubble group(n = 15), the middling microbubble group(n = 15) and the tiny microbubble group(n = 15).The rosette formation rate was counted.JARs were calculated by flow cytometry(FCM).The targeted contrast agent was prepared by mixing SonoVue microbubbles of different diam-eter with rabbit anti-human chorionic gonadotrophin(HCG) antibody.The binding rates of the targeted contrast agent to JARs before and after PBS rinse were analyzed.Results:The binding rate was significantly lower in the large microbubble group(61.7 ± 1.8)% than in the middling microbubble group(82.6 ± 4.5)% and the tiny microbubble group(91.3 ± 5.8)%(P < 0.05).The binding rates of different diameter microbubbles to JARs before and after PBS rinse were different.The middling microbubbles were the most stable ones, with the binding rate of(82.3 ± 4.5)% and(80.4 ± 3.9)% before and after PBS rinse(P > 0.05).The binding rates of the targeted microbubbles labeled with fluorescence to JARs were 68.6%, 81.3% and 89.3% in the large microbubble group, the middling microbubble group and the tiny microbubble group, respectively(P < 0.05).Conclu-sion:The binding capacity of the targeted SonoVue microbubbles to JARs is related to the diameter of the microbubble, which is determined by the shaking method before preparation.Modulating the diameter of SonoVue microbubbles may increase the binding rate and stability of targeted microbubbles to JARs, thus to improve the image of JARs.展开更多
文摘The use of synthetic anabolic steroid methyltestosterone (MT) as growth promoter is prohibited in China. Vali-dations of analytical methods for MT residue in food and the results obtained have become indispensable. The high perfor-mance liquid chromatography (HPLC) method for the detection of MT with liquid-liquid extraction by trichloromethane-methanol in carp muscle tissue was preliminarily validated with reference to the following parameters: recovery (accuracy)at the 1, 5 and 10mg kg-1 level, between-run and within-run CV values (repeatability, also called relative standard deviation(RSD)) and limit of detection. The recoveries were above 80% and the between-run and within-run CV values below 10%for muscle tissue. The limit of detection was 0.05 mg kg-1.
文摘Under high-excitation irradiance conditions to induce fluorescence, the dependence of photobleaching of Coumarin 307 (C307) and acriflavine (ACF) laser dyes in liquid and solid phases have been studied. A cw LD laser source of 1 mW and 407 nm wavelength was used as an exciting source. For one hour exposure time, it was found that the solid dye samples suffer photobleaching more than the liquid dye samples. This is because in liquid solutions the dye molecules can circulate during the irradiation, while the photobleaching is a serious problem when the dye is incorporated into solid matrix and cannot circulate.
基金Supported by a grant from Sci-Tech Program Foundation of GuangdongProvince (No. 2006B35901009).
文摘Objective:To evaluate the impact of the diameter of SonoVue microbubbles on binding characteristics, including the adhesion rate and stability, of a new contrast agent targeted to choriocarcinoma cells(JARs) in vitro, in order to establish a foundation to explore targeted ultrasound imaging for localization of tumor cell antigens and increase the early diagnostic rate for tumors.Methods:The objects were divided into three groups:the large microbubble group(n = 15), the middling microbubble group(n = 15) and the tiny microbubble group(n = 15).The rosette formation rate was counted.JARs were calculated by flow cytometry(FCM).The targeted contrast agent was prepared by mixing SonoVue microbubbles of different diam-eter with rabbit anti-human chorionic gonadotrophin(HCG) antibody.The binding rates of the targeted contrast agent to JARs before and after PBS rinse were analyzed.Results:The binding rate was significantly lower in the large microbubble group(61.7 ± 1.8)% than in the middling microbubble group(82.6 ± 4.5)% and the tiny microbubble group(91.3 ± 5.8)%(P < 0.05).The binding rates of different diameter microbubbles to JARs before and after PBS rinse were different.The middling microbubbles were the most stable ones, with the binding rate of(82.3 ± 4.5)% and(80.4 ± 3.9)% before and after PBS rinse(P > 0.05).The binding rates of the targeted microbubbles labeled with fluorescence to JARs were 68.6%, 81.3% and 89.3% in the large microbubble group, the middling microbubble group and the tiny microbubble group, respectively(P < 0.05).Conclu-sion:The binding capacity of the targeted SonoVue microbubbles to JARs is related to the diameter of the microbubble, which is determined by the shaking method before preparation.Modulating the diameter of SonoVue microbubbles may increase the binding rate and stability of targeted microbubbles to JARs, thus to improve the image of JARs.