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31.
分析了心理阅览室对提高大学生心理素质的作用,并就其场地建设、活动安排、书籍选择等方面提出了具体的指导意见,对心理阅览室建设进行了效果评价。  相似文献   
32.
AIM: To study the inhibitory effect of the extract of Oratosquilla(EOS) on the expression of P53, cyclooxygenase-2(COX-2) and vascular endothelial growth factor(VEGF) in nasopharyngeal carcinoma cell line CNE-2Z.METHODS: CNE-2Z cells were treated with different concentrations of EOS for 24 h. The methods of RT-PCR and immunocytochemistry were used to detect the expression of COX-2 and VEGF at mRNA and protein levels, respectively. The protein expression of P53 was determined by Western blotting.RESULTS: After treated with EOS, the protein expression of P53 in CNE-2Z cells was decreased(P<0.01), and the expression of COX-2 and VEGF at mRNA and protein levels was also significantly decreased in a dose-dependent manner(P<0.01). The expression of COX-2 was positively correlated with that of VEGF(P<0.05), and a positive correlation between the expression of COX-2 and P53 protein(P<0.05) was also observed.CONCLUSION: EOS may play its antitumor effect by inhibiting the expression of P53, COX-2 and VEGF in nasopharyngeal carcinoma cell line CNE-2Z.  相似文献   
33.
刘小年 《安徽农业科学》2007,35(12):3682-3683,3756
当前,新农村建设百业待举,其中村风问题、村治问题与村债问题尤为突出,需要认真面对.村风关系到村民能否全力投入到新农村建设中去,是新农村建设的基础;村治关系到如何组织村民建设新农村,是新农村建设的保证;村债关系到新农村建设的资源配置,是新农村建设的关键.对于如何解决这些问题,提出了对策.  相似文献   
34.
AIM:To investigate the type of chloride channel activated by cisplatin in poorly differentiated nasopharyngeal carcinoma cells (CNE-2Z cells). METHODS:The technique of whole-cell patch-clamp was used to investigate the role of Ca2+ in the activation of cisplatin-activated chloride currents and to analyze the effect of hypertonic stress on these currents in CNE-2Z cells. RESULTS:Chloride currents were induced when the cells were exposed to the calcium-free cisplatin solution, showing the similar density to the currents induced by cisplatin with the presence of extracellular calcium. However, the latency and the peak time of cisplatin-activated currents in the absence of extracellular calcium were prolonged. The activation of cisplatin-activated chloride currents was insensitive to the depletion of intra- and extracellular calcium. Calcium channel antagonist nifedipine had no effect on the cisplatin-activated chloride currents, while hypertonic solution completely inhibited those currents. CONCLUSION:The cisplatin-activated chloride currents are independent on intra/extracellular calcium. The chloride channels activated by cisplatin are not calcium-activated chloride channels, but are probably volume-sensitive chloride channels.  相似文献   
35.
目的探讨低氘水(deuterium-depleted water,DDW)对肝癌HepG2细胞增殖、侵袭能力的抑制作用。方法 HepG2细胞及正常肝细胞LO2用50、75、100、150ppm DDW(纯净水对照组)处理,用MTT法、平皿克隆实验检测细胞增殖、侵袭转移能力,Western blot检测增殖细胞核抗原(PCNA)表达。结果 100ppm DDW处理24h对LO2细胞、72h对HepG2增殖抑制无影响(P>0.05)。HepG2在50、75ppm DDW中细胞克隆数均低于对照组,而LO2细胞克隆数高于对照组(P<0.01)。50、75、100ppm DDW处理后HepG2细胞PCNA表达明显低于对照组(P<0.01)。结论 DDW可抑制HepG2细胞增殖和侵袭能力,但促进正常细胞LO2生长,这可能与PCNA表达下调有关。  相似文献   
36.
目的 研究hsa-miR-196a2基因多态性位点rs11614913与鼻咽癌发病风险及临床病理因素的关系.方法 采用病例对照分析方法,对湖南地区162例汉族人鼻咽癌患者(病例组)及性别、年龄相匹配的135例正常人(对照组)的hsamiR-196a2基因多态性位点rs11614913的基因型进行PCR-RFLP检测,观察该位点多态性分布与鼻咽癌发病风险及临床病理特点的关系.结果 病例组和对照组hsa-miR-196a2基因多态性位点rs11614913基因型频率分布差异无统计学意义(P>0.05),且该位点基因型分布与鼻咽癌患者的临床病理因素无关(P>0.05).结论 hsa-miR-196a2基因多态性位点rs11614913与湖南地区汉族人鼻咽癌发病风险及临床病理因素无关.  相似文献   
37.
A new antibacterial chlorinated benzophenone derivative, (±)-pestalachloride D (1), along with a related analog, (±)-pestalachloride C (2), was recently isolated from the marine-derived fungus Pestalotiopsis sp. isolated from a soft coral Sarcophyton sp. collected from Yongxing Island in the South China Sea. Both chiral HPLC analysis and single-crystal X-ray data indicated that 1 is a racemic mixture. Interestingly, 1 did not exhibit any effect in the zebrafish embryo teratogenicity assay, while 2 led to abnormal growth. The potential impact on zebrafish embryo growth is discussed based on their crystal structures. The main difference of crystal structures between 1 and 2 is that the six-member non-aromatic ring (O4, C10, C9, C8, C2′, and C3′) in 1 exhibits a distorted chair conformation, while 2 shows a distorted boat conformation. Moreover, compounds 1 and 2 both exhibited moderate antibacterial activity.  相似文献   
38.
神经网络在精准农业中的应用研究进展   总被引:2,自引:0,他引:2  
简单论述了人工神经网络的基本结构和原理,总结了人工神经网络在精准农业的应用,重点介绍了人工神经网络在农作物产量预测和虫害预测方面的应用,简略介绍了人工神经网络在农业智能专家系统、农作物生长方面的应用,并对人工神经网络在精准农业的应用前景进行了展望。  相似文献   
39.
在陇中黄土高原干旱半干旱区,采用小区定位试验与室内盆栽模拟试验相结合的方法,对不同生物质炭输入水平下旱作黄绵土N_2O的日排放通量及其影响因子进行连续观测,并确定1天中不同生物质炭处理水平下的最佳观测时间。结果表明:6个生物质炭输入水平处理下(0、10、20、30、40、50 t·hm~(-2)),旱作黄绵土全天表现为N_2O的排放源;无生物质炭添加处理的N_2O排放通量均显著高于其他各处理,随输入水平增加呈U型变化规律,当生物质炭输入水平为30 t·hm~(-2)时,更有利于N_2O气体的增汇减排;各处理N_2O日总排放通量均在白天所占比例最高;温度是环境因子相对稳定条件下N_2O气体排放的主要影响因子,N_2O的排放与地表温度及10 cm土层地温呈不同程度的正相关关系;10 cm土层地温与生物质炭输入量呈显著正相关关系;N_2O气体的最佳同期观测时间为8∶00—9∶00。  相似文献   
40.
Agricultural runoff contributes to water quality problems in the Hawkesbury–Nepean River near Sydney, Australia. This paper presents a case study of sediment, nitrogen (N) and phosphorus (P) losses from a market garden in the Hawkesbury–Nepean catchment. Event-based runoff sampling and flow and rainfall monitoring were carried out at the boundary of an 8-ha commercial market garden near Richmond, NSW, over two years (1995–1997). A record of fertiliser use and soil management was compiled during the runoff monitoring period. Soil management practices were similar to other market gardens on duplex soils in the area. Farm practices were consistent with ‘traditional’ industry practices.Over the 2-year period, stormwater runoff losses from the farm were equivalent to 19 t ha−1 per year of suspended sediment, 11 kg of P ha−1 per year, and 127 kg of N ha−1 per year. Sixty percent of soil loss occurred in summer (December, January and February), reflecting both seasonal climatic changes and soil management practices. Soil erosion was the major mechanism for P mobilisation and transport; however, a significant increase in the event mean concentration (EMC) of soluble P was observed over the 2 years. During this period, we measured an increase in extractable soil P (Bray) in surface soil from 174 to 304 mg kg−1 and a concomitant decrease in P sorption. The highest concentrations of N in runoff occurred after applications of poultry manure and during an extensive fallow period (late spring through to the end of summer). The results show that, in the Sydney region, market gardening on duplex soils using traditional practices is environmentally unsustainable, and may provide economic incentive to bring about change.  相似文献   
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