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991.
GUO Zheng-hui HUANG Hai DU Tao XU Ke-wei CAO Yi CHEN Jie-qing DONG Wen YAO You-sheng LIN Tian-xin XIE Wen-lian JIANG Chun HAN Jin-li HUANG Jian 《园艺学报》2011,27(6):1090-1096
AIM: To study the expression of prostate-specific membrane antigen (PSMA) on the level of phospho-ERK, cell growth and migration of prostate cancer LNCaP cells.METHODS: The method of silencing PSMA was established by lentivirus-mediated RNAi in our early experiment. The cells were divided into 3 groups.In experimental group, the expression of PSMA in LNCaP cells was stably blocked by lentivirus-mediated RNAi. In negative control group, the cells were transfected with lentivirus-mediated control RNAi (without any interference to PSMA).The normal LNCaP cells served as blank control. The cells in these 3 groups were cultured in both 2 environments: normal medium and medium with PD98059 (an inhibitor of ERK phosphorylation). The phospho-ERK was detected by Western blotting and immunocytochemistry. Furthermore, the growth and migration of the cells were evaluated by MTT and transwell assays,respectively.RESULTS: In normal medium, the expression of phospho-ERK was attenuated in experimental group (P<0.05) and the quantity of "positive" cells was less than those in other 2 groups (P<0.05). Furthermore, the growth curves of the cells showed that the growth ability in experimental group was significantly decreased (P<0.05, after 48 h) and the migration ability in experimental group was reduced (P<0.05). In the inhibitory medium, the cells in all 3 groups expressed phospho-ERK at a lower level. Moreover, the abilities of growth and migration in these 3 groups were poorly displayed. These inhibitory effects on phosphorylation of ERK were similar to the cells in experimental group cultured in normal medium.CONCLUSION: PSMA may play a role in up-regulation of phospho-ERK and it may take an advantage in growth and migration of prostate cancer LNCaP cells. 相似文献
992.
HE Yan-jing CHEN Ya-hong QI Yong-fen YAO Wan-zhen BI Xiao-rui GUAN Yu-hong ZHU Rui-xia TANG Chao-shu 《园艺学报》2011,27(6):1169-1175
AIM: To investigate the role of hydrogen sulfide (H2S) in the protection against oxidative stress in rats with chronic obstructive pulmonary disease (COPD).METHODS: The rat model of COPD was established by cigarette smoking (CS) combined with lipopolysaccharide (LPS) instillation. Thirty-two healthy male Sprague-Dawley rats were randomly divided into 4 groups: control group, CS+LPS group, CS+LPS+NaHS (H2S donor) group and CS+LPS+PPG (DL-propargylglycine, an inhibitor of cystathionine-γ-lyase) group. After 30 days, the lung functions of the rats were measured, the histological changes of lungs were observed under light microscope and the pathological scores were calculated. The H2S level in plasma and the protein expression of cystathionine-γ-lyase (CSE) in the lung tissues were measured. The content of malondialdehyde (MDA), the activity of superoxide dismutase (SOD) and catalase (CAT) were detected to reflect oxidative stress.RESULTS: Compared with control group, the peak expiratory flow (PEF) decreased by 24% and intra-pressure (IP) increased by 66% in CS+LPS group. The pathological scores of the lung tissues also increased. Compared with CS+LPS group, no change in the lung function was observed after given NaHS or PPG, but the pathological scores decreased in CS+ LPS+ NaHS group. Compared with control group, the content of H2S in plasma was increased by 26% on day 16. Compared with CS+LPS group, the content of H2S in plasma of CS+LPS+PPG group was decreased by 22% after 30 days. Compared with control group, the protein expression of CSE increased, and no statistical difference among CS+LPS group, CS+ LPS+ NaHS group and CS+LPS+PPG group was observed. Compared with control group, MDA content in the lung tissues was increased by 24% in CS+LPS group, the activity of SOD was increased by 47% and the activity of CAT was increased by 52%. Compared with CS+LPS group, the MDA content in CS+LPS+NaHS group was decreased by 21%, and no statistical difference in the activity of SOD and CAT was observed. The activity of SOD decreased by 33% after given PPG.CONCLUSION: H2S plays a role as anti-oxidant in the rats with COPD. The CSE/ H2S pathway may be involved in the development of COPD. 相似文献
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分别在土路与公路两种路况下,对试验测试得到的车辆振动加速度响应分别从相关性、频域、时域进行信号分析,并对试验条件下的响应信号功率谱密度按照最大峰值进行归一化处理,进而提出路面识别算法。结果表明:路面识别算法可以在一定程度上对路面的频率结构作定性的判断;车辆振动加速度响应信号体现路面不平度特征的信息;分析结论能为路面识别的研究提供参考。 相似文献
996.
选择一种新型高效反应器系统对奶牛养殖场废水进行处理试验研究,这种反应器系统主要包括两级组合生物巢厌氧反应器和砂式沼液处理池。试验结果表明,该系统处理奶牛养殖废水速度快,两级组合生物巢厌氧反应器水力停留时间(HRT)仅为15h,处理效率高,砂式沼液处理池结构简单,对生物巢厌氧反应器出水处理效果好。该新型高效反应器组合系统对化学需氧量(COD)、生化需氧量(BOD)、氨氮(NH3-N)和总固体悬浮物(TSS)的平均去除率分别为97.6%、98.2%、81.3%和98.1%,出水体积质量平均值分别为89.0、27.1、15.7mg·L^-1和64.9mg·L^-1,满足国家二级排放标准。 相似文献
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998.
本文概述了林业碳汇的重要性以及国内外森林生态系统经营现状,分析了安徽省营林措施和存在的问题,并提出提高碳捕获、减少碳排放的相关措施和建议。 相似文献
999.
思茅松人工幼林“3414”施肥试验 总被引:1,自引:1,他引:0
2007年8月,在景谷县具有代表性、长势相当的思茅松人工幼林中,采用"3414"试验设计,对氮、磷、钾3种肥料的不同配比组合进行了施肥试验。结果表明:立地条件对思茅松人工幼林的生长影响较大,思茅松人工幼林施肥应区别不同立地条件采用不同的施肥配比组合,地位指数级为12的立地条件较佳组合为50 g氮肥+150 g磷肥+80 g钾肥,地位指数级为14的较佳组合为100 g氮肥+75 g磷肥+80 g钾肥,地位指数级18的较佳组合为100 g氮肥+150 g磷肥+80 g钾肥。 相似文献
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