Roles of atypical chemokine receptors in progression and metastasis of tumor

Chemokines and their receptors have been implicated mostly in tumor progression and metastasis. Atypical chemokine receptors (ACKRs) comprise a group of 7-transmembrane domain proteins structurally similar to G protein-coupled receptors. However, ACKRs do not induce classical signaling via the typical G protein-mediated pathways. ACKRs efficiently internalize the cognate chemokine ligands and act as scavengers instead. ACJRs are composed of at least 3 members of chemokine receptors:Duffy antigen receptor for chemokines (DARC, also known as ACKR1), D6 (also known as ACKR2) and ChemoCentryx chemokine receptor (CCX-CKR, also known as ACKR4). These receptors bind to and/or internalize their chemoattractant ligands without activating signal transduction cascades leading to cell migration. In this review, we summarize the recent progress regarding the roles of ACKRs in the progression and metastasis of tumor.     

Effect of incorporation of Brassica napus L. residues in soils on mycorrhizal fungus colonisation of roots and phosphorus uptake by maize (Zea mays L.)

Plants in the Brassicaceae family are known to contain thioglucoside compounds that produce isothiocyanates when tissues are disrupted. These chemicals have a negative effect on soil-borne fungal pathogens, and possibly on vesicular–arbuscular mycorrhizal (AM) fungi. We investigated the effect of incorporation of Brassica napus L. residues in a soil on mycorrhizal colonisation of roots, P uptake and growth of following maize (Zea mays L.) crop. A pot experiment was carried out in a glasshouse with pre-inoculation with Glomus intraradices (+I and −I), incorporation of B. napus L. residues (+R and −R) and mineral P fertilization (+P and −P) as studied factors. The soil used was a neutral loamy soil with low P availability. The pots were planted with maize (Z. mays L.). Phosphorus uptake, plant biomass, total leaf area per plant and area of individual leaves (rank 4–7) were significantly larger in +P treatments than without P addition, thus confirming that the soil used for the experiment was P deficient. Incorporation of B. napus L. residues had also a positive effect on P uptake, plant biomass, total leaf area per plant and area of individual leaves (rank 5–7). These effects were more pronounced in −P treatments than in +P treatments. There was no effect of pre-inoculation with G. intraradices on P uptake and P dependant variables. The percentage of the root length that was colonised by mycorrhizae was lower in +P treatments but it was not significantly affected by other studied factors. Altogether the results showed that B. napus L. residues have mainly acted as a source of P. There was no evidence of a negative effect of the incorporation of B. napus L. residues on the colonisation of maize roots by mycorrhizae.     

大批量注射花鲈疫苗方法的研究

研究了大批量注射疫苗中不同麻醉剂FA100的浓度、不同注射深度、不同注射部位和不同注射流程对体长(20.0±1.2)cm花鲈成活率的影响。试验结果表明,用麻醉剂与海水体积比为1∶2000的麻醉剂麻醉后,将鱼轻轻滑至容器壁腹腔注射,注射深度4 mm,成活率最高,可以避免鱼体表机械损伤,提高注射效率和成活率。利用此方法9 d共注射花鲈21万尾,成活率高达99.76%。     

手性流动相添加剂在纤维素-三(3,5-二甲基苯基氨基甲酸酯)柱上的应用

以微晶纤维素和3,5-二甲基苯基异氰酸酯为原料合成了纤维素-三(3,5-二甲基苯基氨基甲酸酯),涂敷于氨丙基硅烷化硅胶上制成手性固定相.并以β-环糊精衍生物为手性流动相添加剂在手性柱上进行对映体的拆分.结果表明:当使用手性固定相和含有手性添加剂的流动相分离手性化合物时存在手性两相协同作用,其中以2,3,6-三甲基-β-环糊精(TM--βCD)为流动相添加剂时的效果最好.     

利用野生乡土植物建设生态园林城市

建设具有特点的生态园林城市是现代城市环境建设的目标。利用野生乡土植物充实城市园林植物种类,可以增强园林的观赏性和乡土气息,改善环境的生态效应,是一些城市尤其是林区城镇绿化、美化建设的不错选择。     

循环水养殖系统生物滤器负荷挂膜技术

循环水养殖系统启动运行前往往需要经过一段时间的生物膜预培养,使生物膜达到成熟稳定,从而保证系统的水质净化功能。本研究通过养殖试验,研究了生物滤器负荷挂膜的技术方法,以期实现生物膜的快速成熟和系统的快速启动。为此,构建了6组循环水系统组成的养殖车间,建成后立即投入试验生产。试验为期120 d,养殖种类为红鳍东方鲀,初始放养平均体重(632.5±2.26)g。期间,红鳍东方鲀平均增重29.91%,养殖成活率98.7%,养殖密度由(19.34±1.89)kg/m3增加到(32.17±3.40)kg/m3,投饵率由0.2%增加到0.5%–0.7%,每日换水量由50%逐渐减至10%。结果表明,在生物膜的生长期,通过对投饵量及新水补充量的有效调节,可以把养殖水体中的氨氮和亚硝氮浓度控制在安全范围以内,以保证养殖鱼类的生长。生物膜在50天左右达到完全成熟,此后便可依靠生物膜的净化作用将氨氮浓度控制在0.5?1.2 mg/L、亚硝氮浓度控制在0.2?0.5 mg/L、pH值控制在6.5–7.5、COD值低于4 mg/L、细菌总数控制在800–2100 cell/ml的安全范围内。利用生物滤器负荷挂膜技术,在合理调控水质指标的条件下,循环水养殖系统建成后可以立即投入生产,实现生物滤器挂膜与养殖生产的同步进行。     

少儿图书馆建立未成年人信息素养教育平台的探讨

本研究对国内外未成年人信息素养现状的研究,提出少儿图书馆建立信息素养教育平台的可行性,并提出建立少儿图书馆信息素养平台的构想,为完善我国少儿信息素养教育提供参考作用。     

脊髓型颈椎病手术入路选择的Meta分析

目的：系统评价脊髓型颈椎病（cervical spondylotic myelopathy,CSM）的前路手术与后路手术方式的临床效果。 方法：计算机检索Cochrane图书馆临床对照试验数据库(CENTRAL)、PubMed、Embase、中国生物医学文献数据库（CBM）、中国期刊全文数据库(CNKI)、万方科技期刊全文数据库与重庆维普信息数据库(VIP)等,检索时间范围为1991年1月至2010年8月。按纳入、排除标准选择纳入脊髓型颈椎病的前路手术与后路手术方式的对照研究,评价纳入研究质量,并采用RevMan4.2进行定量分析。结果：共纳入10个对照研究。Meta分析结果表明,平均脊髓术后改善率指标的合并效应量标准化均差(SMD)为0.63（0.19,1.06）,术后并发症发生率指标的合并相对危险度（OR值）为2.40(1.15,4.37)。结论：前路手术入路途径治疗脊髓型颈椎病与后路手术入路途径相比,可提高病人平均脊髓术后功能改善率,但前路手术的术后并发症发生率要远远高于后路手术。     

大连市休闲农业发展问题与对策建议

近年来,休闲农业呈现出如火如荼的发展态势,并出现多种发展模式。大连市休闲农业的发展不仅满足了消费者对静谧甜美生活的需求,并为当地的经济和社会的发展做出了重大贡献。在界定休闲农业内涵的基础上,阐述并评价了国内现有的休闲农业发展模式,采用问卷调查和访谈法等分析研究大连市休闲农业的发展现状与存在问题,提出了相应的发展对策与建议。