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31.
32.
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
33.
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
34.
从油橄榄引种看我国木本食用油料产业的发展 总被引:2,自引:0,他引:2
为了科学制定木本油料产业发展规划,论述了我国发展木本食用油料产业的优势和特点,分析了橄榄油的营养价值和市场动力,简述了我国油橄榄引种栽培的历史,指出了我国目前木本食用油料产业发展中存在的主要问题,并提出了促进木本食用油料产业发展的对策与措施。 相似文献
35.
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
36.
以聚L-乳酸(PLLA)和麦草(WS)为原料,以N-甲基吗啉-N-氧化物(NMMO)为溶剂,采用溶液共混法制备了PLLA/WS共混物。首先将麦草溶解在NMMO后,再添加聚L-乳酸并溶解,制备聚L-乳酸与麦草的共混溶液。共混溶液采用浇膜法制备PLLA/WS共混物,采用差示扫描量热法、X射线衍射法、傅里叶变换红外光谱、热重分析和扫描电镜等方法对所得的共混物进行表征。结果表明,聚L-乳酸与麦草可以形成均匀的共混溶液。共混物中PLLA与麦草组分之间具有较强的相互作用,相容性较好。当共混物中PLLA的质量分数为50%时,共混物可以形成结晶结构,且随着PLLA含量的增加,其结晶更加完美,熔点与热稳定性提高。共混物薄膜断面结构较为致密,这说明PLLA与麦草相容性较好,混合均匀。通过调节聚L-乳酸和麦草的配比,可以制备不同性能的生物高分子材料。 相似文献
37.
普陀水仙花大球栽培技术试验初报 总被引:4,自引:0,他引:4
对普陀水仙花采用优质种球繁育技术、湿生栽培技术、种球阉割技术、病害综合防治技术和氮、磷、钾合理配方施肥技术5项技术措施后,其病害减轻,分生球减少,主球的大球率从原来的30%以下提高到60%以上. 相似文献
38.
原料表面碱液处理对稻草碎料板力学性能的影响 总被引:1,自引:0,他引:1
在实验室条件下探索了稻草原料表面碱液处理对稻草碎料板力学性能的影响.试验表明,处理后的稻草碎料板的内结合强度比处理前有大幅度提高,弯曲弹性模量和静曲强度比处理前则有所下降,但都达到了相关的国家标准;2h吸水厚度膨胀率升高,超过国家标准.因此稻草表面碱液处理提高了稻草原料表面润湿性和胶合强度,但对稻草碎料板的力学性能有影响. 相似文献
39.
利用我国滇产松茸9924菌株及日产松茸99606菌株,分别对云南松、华山松、马尾松、火炬松、湿地松及加勒比松6种松树幼苗实施人工菌根接种。研究结果表明,接种后90d的云南松和湿地松分别有75%和78.1%的幼苗受感染并形成菌根;接种后180d,6种松树幼苗分部都可形成菌根,菌根感染率分别达90.63%-100%,感染指数达50.00-84.68;菌根形态主要有棒状、二叉分枝状及多叉分枝状3种;随树种的不同,各类菌根形态所占比例也不同;不同树种根系上形成菌根的长度也有差异,以马尾松根系上的菌根最长,华山松的菌根最短;此外,各种组合之间在菌套厚度,哈蒂氏网结构上也略有差别。 相似文献
40.
AIM: To investigate the changes of peroxisome proliferator-activated receptors (PPAR)α/peroxisome proliferator activated receptor coactivator 1 alpha (PGC-1α) in doxorubicin (DOX) induced dilated cardiomyopathy (DCM) and its effect on the energy metabolism and myocardial function in mice. METHODS: Forty mice were randomly divided into 4 groups: control group, DOX group, PPARα inhibitor group and PPARα agonist group. The DCM model was established by injection of DOX. The protein levels of PPARα/PGC-1α were detected. The PPARα inhibitor and PPARα agonist were used 2 weeks beforeinjection of DOX. The contents of adenine acid and phosphocreatine (Pcr) in the mitochondria were measured by high-performance liquid chromatography (HPLC). The ANT activity was analyzed by the atractyloside-inhibitor stop technique. The changes of the echocardiography and hemodynamics were also observed. RESULTS: DOX induced DCM model was successfully established. The protein levels of PPARα and PGC-1α in control group were significantly higher than those in DOX group (P<0.05). Both of the high-energy phosphate contents and the transport activity of ANT were decreased in DOX group (P<0.05), and the hemodynamic parameters were disordered (P<0.01). Compared with DOX group, PPARα inhibitor pre-treatment significantly reduced the PPARα/PGC-1α expression. Meanwhile, high-energy phosphate contents in the mitochondria and the ANT transport activity of the mitochondria decreased, as well as the left ventricular function (P<0.05). On the other hand, PPARα agonist significantly increased the expression of PPARα and PGC-1α, and improved the transport activity of ANT. In addition, the hemodynamic parameters were ameliorated, but the high-energy phosphate contents of the mitochondria did not significantly change. CONCLUSION: PPARα/PGC-1α plays an important role in the regulation of ANT transport activity in dilated cardiomyopathy induced by DOX, and the activation of PPARα/PGC-1α has protective effects on the DCM induced by DOX. 相似文献