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91.
HPLC法检测发酵玉米粉中的黄曲霉毒素B1、B2、G1、G2 总被引:2,自引:0,他引:2
发酵玉米粉用甲醇∶水(80∶20,V∶V)提取黄曲霉毒素(AFT),经免疫亲合柱(IAC)分离纯化、在线光化学衍生器柱后衍生化后,反相高效液相色谱(HPLC)荧光检测器测定AFT(B1、B2、G1、G2)含量。4种毒素在0.5ng/g和2ng/g2个水平下,样品加标回收率平均值分别为B188.0%和93.6%、B285.2%和85.3%、G192.4%和91.5%、G289.6%和85.6%;5次测定的标准差分别为:B12.5和6.3、B23.5和6.0、G12.8和9.0、G22.3和6.9;4种毒素的方法检出限均达到0.05ng/g。 相似文献
92.
奶牛胚胎性别控制技术的试验研究进展 总被引:13,自引:2,他引:13
应用LAMP法进行了613枚胚胎的性别鉴定结果,雌性胚胎302枚(49.3%),雄性胚胎311枚(50.7%),移植成功率平均为40.9%(122/298),出生后代中与性别鉴定结果一致的121头,性别鉴定准确率为96.0%(121/126)。应用奶牛性腔胶囊后输精的14头供体母牛,共采集69枚可用胚胎,对其中64枚胚胎进行性别鉴定,确定雌性胚胎的比例为71.9%(46/64),头均获4.9枚可用胚胎。应用奶牛性控液对3头供体母牛宫注后输精,共采集26枚可用胚胎,经性别鉴定后确定雌性胚胎比例为73.1%(19/26),头均获可用胚胎8.7枚。应用分离X精子冷冻精液对12头供体母牛进行输精,对采集到的61枚胚胎进行性别鉴定后,确定雌性胚胎比例为100%(61/61),头均获得可用胚胎5.5枚。11枚性控冷冻胚胎移植后,40d以上未返情率为63.6%(7/11)。用分离的X精子冷冻精液对供体母牛输精后,可获得与未分离冷冻精液输精后相接近的超排供体母牛采集胚胎的数量和质量。 相似文献
93.
94.
阐释了园林构成要素中的必然性要素和偶然性要素及其相互关系与运用意义;以昆明世博园中“齐鲁园”为例,辩识了“齐鲁园”中必然性与偶然性园林要素,分析了诸要素在特定园林环境布局中的运用。 相似文献
95.
AIM:To investigate the effect of LY980503(a benflumetol derivative)on multidrug resistance of tumor cell line using DNA microarray.METHODS:Total RNA was extracted from multidrug resistant MCF/DOX cell line. cDNA microarray containing 320 cDNAs was used to detect the gene expression profile.RESULTS:9 down-regulated genes and 1 up-regulated gene were identified after multidrug resistant MCF/DOX cells were treated with LY980503.CONCLUSION:LY980503 can effectively reverse the resistance of MCF/DOX to DOX in vitro by adjusting the expression of multi-genes. 相似文献
96.
AIM:To establish cell line FL-POLκ- and to study the role ofPOLκ(polymerase kappa) on genetic stability.METHODS:A mammalian expression vector expressing antisense POLκ gene fragment pMAMneo -amp--POLκ was constructed by cloning the 1 690-1 918 fragment of POLκ gene into the mammalian expression vector pMAMneo-amp- in antisense orientation. FL cells were fransfected with this antisense RNA expressing vector and selected by G418. Based on the shuttle-plasmid pZ189, the mutation assay was made.RESULTS:The spontaneous mutation frequency of supF tRNA gene in the plasmid replicated in the FL- POLκ- was 11.2×10-4, while it was 4.9×10-4 and 3.7×10-4 in the control cells FL and FL-M, respectively.CONCLUSION: POLκ playes an important role in maintenance of genetic stability. 相似文献
97.
98.
JIANG An-li KANG Lu-dong ZHAO Chun-hua BI Wen-xiang HU Xiao-yan KONG Feng XU Song-de 《园艺学报》2003,19(1):55-58
AIM: In order to evaluate the applicable value of LDL as a targeted vehicle for chemotherapeutic agents, we investigated and compared the inhibitory effects of LDL-ACM complex and free ACM on nude mice's subcutaneous implanted tumors derived from gastric cancer cell lines, SGC-7901 and NKM-45. METHODS: LDL-ACM complex was prepared and the tumor model of nude mice was established by subcutaneous implantation of SGC-7901 and NKM-45. Then, the groups of nude mice developed subcutaneous implanted tumors were received either LDL-ACM complex or free ACM. Subsequently, the tumor size, weight and leukemia cell counts were measured and the rates of tumor-inhibition and the survival were compared among the groups. RESULTS: The inhibitory effects of LDL-ACM complex on the tumors, especially on SGC-7901 implanted tumors were much more obvious than that of free ACM. It was also indicated that the action of LDL-ACM complex was mediated by LDL receptor. CONCLUSION: These results showed that LDL-ACM complex had significant inhibitory effects on the implanted tumors and the effect might be mediated by LDL receptor. 相似文献
99.
100.
HEI Zi-qing WU Wei-kang SUN Hui-lan HUANG He-qing TAN Hong-mei LUO Han-chuan 《园艺学报》2003,19(3):345-347
AIM:To observe the effects of Sini decoction on atherosclerosis(AS) and ceramide content of aorta in rabbits. METHODS:28 rabbits were randomly divided into three groups. Control group was fed with a normal diet; High cholesterol group was fed 1% cholesterol and 5% fat diet; Sini decotion+ high cholesterol group was fed 1% cholesterol and 5% fat diet plus Sini decotion (4.2 g·kg-1·d-1). At the end of study, the plaque area were measured, the atorta ceramide and cell apoptosis were also detected. RESULTS:Sini decotion diminished lipid plaque area on the aortic endothelium, reduced the levels of aorta ceramide and the apoptosis index. CONCLUSION:Sini decoction has an inhibitory effect on AS, the mechanism may be that Sini decotion reduces concentration of ceramide in aorta. 相似文献