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991.
992.
高效液相色谱法测定猪血浆及组织中喹赛多及其脱二氧代谢物 总被引:1,自引:0,他引:1
建立了测定猪血浆及肝脏、肾脏、肌肉等组织中的喹赛多及其代谢物脱二氧喹赛多的高效液相色谱(HPLC)法.血浆样用甲醇沉淀蛋白后离心取上清液进样测定.组织样先用乙腈匀浆,用正己烷脱脂后作HPLC检测.色谱柱为ODS C18柱;流动相血浆样测定为乙腈水(2080),组织样测定为甲醇水(4258),流速为1.0 mL/min;紫外检测波长305 nm.药物工作液质量浓度范围为0.005~0.500 mg/L时,血浆样品及组织样品测定条件下药物质量浓度与响应值均具良好线性关系,相关系数>0.999.血浆中药物质量浓度为0.02、0.10、0.50 mg/L时,喹赛多及脱二氧喹赛多的回收率均大于70%,组织中药物含量为0.05、0.20、1.00μg/g时,肌肉样品的回收率均大于70%,肝脏、肾脏样品则为50%~80%.本试验条件下,喹赛多及其脱二氧代谢物的最低检出质量浓度,血浆样品分别为0.01、0.02mg/L,组织样品2种检测物均为0.025μg/g.测定了工作液3种质量浓度0.01、0.05、0.25 mg/L的仪器精密度,日内相对偏差<8.0%,日间相对偏差<17.0%. 相似文献
993.
In order to clarify the mechanism of rockburst, using the specified loading equipment and the CT machine, the real-time computerized tomography testing of coal under the uniaxial compression was completed. Through CT scanning, the clear CT images which included the stage from the microcrack clousre to the microcrack growth, bifurcation, development, failure and the post-failure stage were obtained. According to the CT values, the meso-damage evolution of coal under uniaxial compression was analysed, which provided the basis for the meso-damage evolution. 相似文献
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文章叙述了在中密度纤维板产品工厂设计中尝试应用循环经济理论中的减量化原则,从提高原材料综合利用率,降低能源动力消耗量,清洁生产过程三方面入手,取得了较好的效果。 相似文献
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AIM:To study the effect of L-Arg on plasma content of endothelin (ET) and the expression of proto-oncogene c-fos mRNA in the left ventricle of rats with renovascular hypertensive hypertrophy. METHODS: The level of c-fos mRNA were measured by in situ hybridization. The ET in plasma were measured by radioimmunoassay. RESULTS:After eight weeks of treatment with L-Arg, the expression of c-fos decreased markedly (P<0.01). The ET content in plasma also decreased significantly by L-Arg(P<0.01).CONCLUSION: Plasma ET content and the expression of c-fos in the left ventricle of rats with renovascular hypertensive hypertrophy could be decreased by L-Arg administration. 相似文献
1000.
PEI Yaping ZHAO Jin SUN Na SUN Panpan SUN Yaogui FAN Kuohai YIN Wei LI Hongquan 《畜牧兽医学报》1956,51(12):3068-3075
Ovarian granulosa cells provide a special microenvironment for follicle formation and maturation through interaction with oocytes and their own secretion. A variety of harmful stimuli can cause granulosa cell apoptosis and metabolic disorders, reduce the quality of oocytes and have a negative impact on embryo formation. Zearalenone (ZEA) is a common cause of ovarian granulosa cells injury in the livestock industry, which is produced by mycotoxins, and lack of effective treatment drug. Therefore, in the current study zearalenone was used to induce ovarian granulosa cell injury and to explore the protective effect of caffeic acid on zearalenone-induced ovarian granulosa cell apoptosis in mice. Mouse ovarian granulosa cells were isolated by mechanical method, and indirect immunofluorescence was used to identify the isolated cells. MTT assay was used to determine the effect of caffeic acid on the activity of normal mouse ovarian granulosa cells.After granulosa cells were co-treated with caffeic acid (200, 100 and 50 μg·mL-1) and ZEA for 24 hours, and control and ZEA group were set up at the same time, cell morphology and adherence were observed under a microscope. MTT was also used to detect cell viability. Caspase-3 mRNA expression level was detected by qRT-PCR. Cleaved-caspase-3 and cleaved-PARP protein expre-ssion levels were determined by Western blot. The results showed that positive FSHR staining appeared in cell cytoplasm of the test group, which confirmed that the isolated cells were mouse ovarian granulosa cells. The cell viability was above 90% which showed that caffeic acid had no toxic effect on granulosa cells. Compared with control group, ZEA group had smaller cell size, poor adherence, increased cell gap, and significant reduction in cell viability (P<0.001). Furthermore, the relative expression of caspase-3 mRNA, and cleaved-caspase-3 and cleaved-PARP protein level were significantly increased (P<0.001) compared with the control group. After caffeic acid treatment, cell gap was reduced, adherence was tight, cell viability was significantly increased (P<0.001). Caffeic acid significantly reduced zearalenone-induced increase in caspase-3 mRNA, and cleaved-caspase-3 and cleaved-PARP protein expression level (P<0.001). This study indicated that caffeic acid can restore granulosa cell viability by inhibiting ZEA-induced apoptosis. 相似文献