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51.
采用硫酸铵分级沉淀和CytochromeC -Sepharose 4B亲和层析 ,从牛心线粒体中纯化了细胞色素C氧化酶 (CytochromeCOxidase ,简称CCO ) ,其比活性为 1 7 88s- 1 ·mg- 1 ,聚丙烯酰胺凝胶电泳为一条带 ,血红素A (HemeaA)含量达到 1 5 4nmol/mg。纯化后的CCO具有典型的CCO特征 ,还原态CCO峰值出现在 60 5nm和 443nm ,氧化态CCO峰值出现在 598nm和 42 4nm。CCO的稳态动力学参数Vm1、Km1、Vm2 、Km2 分别为 1 42s- 1 、 0 53μmol/L、 2 71s- 1 、 1 81 μmol/L。 相似文献
52.
AIM:To explore the inhibitory mechanism of isorhapontigenin (ISO) on the proliferation, migration and invasion of UMUC3 bladder cancer cells. METHODS:Human UMUC3 bladder cancer cells were pretreated with ISO, and the proliferation of the cells was observed under phase-contrast microscope and by ATPase assay. The expression of cyclin D1 was determined by RT-PCR and Western blotting. The cell cycle alteration was detected by flow cytometry, and the cell migration was examined by wound-healing assay. RESULTS:Over 20 μmol/L of ISO significantly inhibited the proliferation of UMUC3 cells with the IC50 of (22.5±2.8) μmol/L. The mRNA and protein levels of cyclin D1 in UMUC3 cells were markedly decreased after treatment with ISO. Exposure of UMUC3 cells to low dose (5 μmol/L) of ISO led to significant induction of G0/G1 growth arrest at both 12 h (58.82%) and 24 h (63.94%), compared with the negative control cells (47.33%) without inducing obvious apoptosis. ISO at dose of 5 μmol/L also markedly inhibited the cell migration. CONCLUSION:ISO significantly exhibits inhibitory effects on the proliferation and migration of human bladder cancer cells by down-regulation of cyclin D1 expression accompanying with G0/G1 cell cycle arrest. 相似文献
53.
Wang G Song T Yu Y Liu Y Shi W Wang S Rong F Dong J Liu H Cai X Zhou EM 《Veterinary immunology and immunopathology》2011,142(3-4):170-178
Porcine reproductive and respiratory syndrome virus (PRRSV) infection compromises the host's innate and adaptive immunity. The aim of this study was to investigate the immune responses of piglets infected with highly pathogenic (HP) PRRSV (HuN4 strain) with or without the immunization with CH-1R attenuated PRRSV vaccine. The response was evaluated for the clinical signs, pathological changes and virus load in immune organs, antibody responses and levels of serum IFN-γ, IL-4 and IL-10. The result showed that in comparison with the piglets received the immunization, the piglets infected with HP-PRRSV alone had the thymus atrophy, decreased serum levels of IL-4 and increased serum levels of IL-10 and INF-γ. These results suggest that elevated IL-10 levels at the early stage of the infection may enhance virus survival and delay the induction of protective immunity, while increased levels of IL-4 induce the effective immune responses and increase the animals' health status. 相似文献
54.
Yu Xin Chi Shakeel Ahmad Ke Jun Yang Jian Fu Li Yang Xun Bo Zhou Hong De Zhu 《Journal of Agronomy and Crop Science》2023,209(1):161-175
Water scarcity is known to be a strong limiting factor affecting maize grown and yield in cold semi-arid regions. Numerous studies have shown that rehydration improves maize growth. Our study aimed to explore the effects of rehydration treatments on maize growth and yield under water and nitrogen stress during different growth stages. We selected the drought-tolerant maize variety Nendan 19 (ND19) and subjected it to water stress during the V6 (sixth-leaf), R2 (filling) and R6 (maturity) growth stages and a rehydration treatment after each stress stage. Our results indicated that N1 (N100 kg N ha−1) and N3 (N300 kg N ha−1) treatments significantly increased the leaf moisture status relative to water content (RWC), bound water content (BWC), free water content (FWC) and water potential (WP)) at different growth stages. Similar trends were observed in the accumulation of plant leaf and root hormones (zeatin+zeatin riboside, indole-3-acetic acid, abscisic acid and gibberellic acid), photosynthetic pigments and chlorophyll fluorescence. However, under the same water stress conditions, they decreased as the N rate increased and reached a minimum value in the S3 (water stress for N3) treatments. In addition, with growth stage advancement and extension of the rehydration time, both showed a gradual upward trend. The results showed that to save water resources in the cold semi-arid region, rehydration treatments (R2S1 and R2S3) significantly increased the photosynthetic pigments and chlorophyll fluorescence parameters, leaf moisture status, biomass, 100-grain weight, hormone content, ear characteristics and grain yield of maize. 相似文献
55.
L. V. Rimareva M. B. Overchenko N. I. Ignatova N. V. Shelekhova E. M. Serba A. Yu. Krivova 《Russian Agricultural Sciences》2017,43(2):186-189
The ionic composition of the of the intracellular content of the alcohol yeast Saccharomyces cerevisiae R. 1039 biomass was studied for confirmation of their use perspectiveness as a mediator to enable the management the mineral content of food in the manufacture of food and feed additives. The ionic composition of the obtained extracts were identified using the method of capillary electrophoresis. It is found that the quantitative ion content in the cell extracts depends on the concentration of the nutrient medium. When the yeast S. cerevisiae R. 1039 was cultivated on the medium with the soluble solids concentration of 30%, the intracellular ion content in the extracts was 1.3 times higher than when the yeast was cultivated on 12% wort by increasing the concentration of chlorides, sulfates, formates, potassium ions, and calcium. The yield of the yeast S. cerevisiae R. 1039 biomass increased 1.6 times per unit of volume of the medium with increase of the soluble solids concentrations from 12% to 30%. 相似文献
56.
57.
Xia Yun Yu Ermeng Li Zhifei Zhang Kai Tian Jingjing Wang Guangjun Xie Jun Gong Wangbao 《Fish physiology and biochemistry》2021,47(4):907-917
Fish Physiology and Biochemistry - Type I collagen is proven to make an important contribution to fish muscle quality. Our previous study has shown the Smad4-dependent regulation of type I collagen... 相似文献
58.
59.
枯草芽孢杆菌可湿性粉剂对玉米大斑病的田间防效 总被引:2,自引:0,他引:2
玉米大斑病发生期,在田间采用不同处理方式对玉米大斑病进行处理,并测定其对玉米大斑病的田间防治效果及其对玉米的安全性。结果表明,4种施药处理对玉米大斑病均有一定防效,枯草芽孢杆菌单次用量300g/hm2喷药2次、450g/hm2喷药1次、300g/hm2加高效助剂有机硅75g/hm2喷药2次、450g/hm2加高效助剂有机硅75g/hm2喷药1次的防治效果分别为81.25%,68.45%,82.63%,74.33%;试验剂量范围内,枯草芽孢杆菌对玉米生长安全;其中,枯草芽孢杆菌单次用量300g/hm2喷药2次对玉米大斑病有很好的防治作用,可在生产上大面积使用。 相似文献
60.
中国铁线莲属观赏种质资源研究进展 总被引:1,自引:0,他引:1
总结了目前国内铁线莲属观赏种质资源调查及评价、引种栽培及繁殖、细胞及分子生物学以及育种等方面的研究进展。提出今后应在铁线莲属观赏种质资源收集保护和评价、新品种选育及产业化关键技术等方面加强研究,尤其应重点加强新品种选育研究:一方面,充分挖掘现有种质资源中表现优良的野生种质直接进行产业化开发;另一方面,结合园林应用及市场需求,通过常规杂交、诱变及分子辅助育种等手段广泛开展新品种选育,培育适应性、抗逆性和观赏性俱佳的自主知识产权铁线莲新品种。 相似文献