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991.
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.
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   
993.
石育秋宝是由两个自交不亲和系88-11-1和87-10-1配制而成的大白菜一代杂种。生长期88 d(天)左右,叶球直筒束心型(个别顶部尖),株高59~61 cm,开展度63 cm,叶球纵径52~54 cm,横径12~14 cm。丰产性好,每667 m2净菜产量6 000~7 000 kg。品质优,结球紧实,纤维少,口感好,耐贮藏,不易抽薹|高抗病毒病和黑腐病,抗霜霉病。适宜在北京、天津、河北、辽宁、黑龙江、山东等地作秋季中晚熟大白菜种植。  相似文献   
994.
茄子新品种哈农杂茄1号的选育   总被引:1,自引:0,他引:1  
哈农杂茄1号是以T142为母本,以T72为父本杂交配制而成的茄子一代杂种。早熟,植株长势强,叶绿色,茎紫色;果实长棒形,长25~28 cm,横径4.5~5.0 cm,果皮黑亮,绿萼,色泽好,果肉白色细嫩,单株结果10~12个,单果质量130~140 g,生育期110~115 d(天);高抗黄萎病;耐弱光,耐贮运;平均每667 m2产量5 000 kg以上,适合在各紫长茄产区种植。  相似文献   
995.
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   
997.
对于独立院校计算机人才的培养现状和社会对计算机人才的实际需求进行了研究,分析了独立院校培养计算机应用型人才的必要性,并对独立院校如何培养和提高计算机应用型人才的综合素质进行了深入探讨。  相似文献   
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   
1000.
试验通过对比舍外散放蛋鸡与舍内笼养蛋鸡在体重、胫长和胫围等方面的差异来研究饲养方式对鸡产蛋前期生产性能的影响.结果表明:散放鸡体重在8、10、12周龄显著低于同周龄笼养鸡;散放鸡胫长在10、12周龄显著低于同周龄笼养鸡;散放鸡胫围在10周龄显著低于同周龄笼养鸡.笼养鸡和散放鸡各周龄的胫长和胫围变异系数均小于10%,均匀...  相似文献   
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