Neuropeptide Y inhibits corticosterone secretion by isolated rat adrenocortical cells

Summary Studies with isolated rat adrenocortical cells have shown that neuropeptide Y (NPY) inhibits both basal and ACTH-stimulated corticosterone secretion. These results suggest the regulatory role of NPY in corticosterone secretion from the adrenal gland, especially during stress.Supported in part by a grant CPBP 06.03.3.16.     

结肠腺癌中结肠癌干细胞的分离、鉴定

目的从人结肠腺癌组织中分离、鉴定结肠癌干细胞，并初步观察其生物学特性。方法利用新鲜结肠腺癌组织，无血清悬浮成球培养，流式细胞检测ESA、CD44表达情况，体外观察其诱导分化及CK20、Muc表达情况，Balb／C小鼠移植观察其成瘤情况。结果从人原代结肠腺癌中分离、纯化EpCAM^high CD44^＋结肠癌干细胞，结肠癌原代细胞中EpCAM^highCD44^＋细胞比例为1．7％～38％（平均5．4％）。单克隆形成实验证实结肠癌组织中存在肿瘤干细胞。其比例为（2．07±0．11）％，分离获得的EpCAM^highCD44^＋细胞能在无血清培养基中“成球”，在血清诱导下能贴壁分化；将EpCAM^highCD44^＋细胞移植在Balb／C裸鼠体内，表现出很强的致瘤性，移植瘤中EpCAM^highCD44^＋细胞比例为3．6％～43．2％（平均15．2％），所有的移植瘤经组织学测定，均形成腺管样结构，表达结肠特异性分化标志物CK-20、中性上皮粘蛋白（neutral epithelial mucins，Muc）。结论人结肠腺癌组织中存在EpCAM^highCD44^＋细胞群，具有和普通干细胞相类似的无限增殖、自我更新和分化能力。     

地方网络媒体对外传播研究——以“河南安阳发现曹操墓”专题为例

本文以大河网、人民网、新浪网新闻频道制作的"河南安阳发现曹操墓"专题为研究样本,通过报道内容全面性、深度、传播符号以及互动性四个方面的对比,认为大河网在对外传播塑造自身形象上,应进一步加强信息的全面性,增加深度报道,丰富信息传递手段以及加强对论坛的有效管理。     

化学沉淀-磁絮凝深度快速除磷的研究

采用化学沉淀法研究Al2(SO4)3、FeCl3、CaCl2的药剂用量和pH值对除磷效果的影响,探讨非磁性悬浮物磁性接种的机理,并分析了铝、铁、钙的磷酸盐沉淀物由于加入磁种而变得易于沉降,特别是在磁场力作用下沉降速度加快的原因.结果表明,Al2(SO4)3、FeCl3、CaCl2是磷酸根离子的有效沉淀剂,在适当的药剂投加量和pH值条件下,废水经过处理后,剩余磷的浓度小于0.5mg/L;生成的铝、铁、钙的磷酸盐沉淀物颗粒与Fe3O4颗粒在某一pH值下表面电性相反,易发生相互凝聚;磁性接种的铝、铁、钙的磷酸盐沉淀物不仅变得更重,而且在磁场中还受到与重力方向相同的磁场力作用.     

赏乐杂谈

赏乐如读书,如赏诗、赏画,懂得熟赏、精赏才能体会赏乐之乐.     

An adaptive routing protocol based on relative positions in VANETs

After presenting weaknesses of several classic routing protocols applied in vehicular ad hoc networks (VANETs) by a qualitative comparison,this paper proposes a novel self-adaptive routing protocol,nam...     

也谈《红楼梦》霍译本的读者关照

霍克斯在《红楼梦》的翻译中,需要关照西方读者的思维认知、社交语言、宗教信仰、文化生活等方面。这些关照既有积极又有消极的成分。当霍氏关照西方读者的思维认知和社交语言时,读者关照是积极地;对宗教信仰和文化生活的关照却因为文化负载词的失当处理,容易形成消极关照。     

生态技术创新是林业可持续发展的必然选择

通过分析林业生态技术创新的内涵及传统经济发展观的理论缺失,阐述林业生态技术创新的可持续发展功能,生态技术创新是林业可持续发展的必然选择。     

胡萝卜汁中胡萝卜素的快速测定

胡萝卜汁中由于含有较多的果胶，在进行胡萝卜素测定时，很难将胡萝卜素提取完全，造成较大的测定误差。本法采用了提取胡萝卜素时先加入无水Ｎａ２ＳＯ４洗涤净化，然后直接比色测定胡萝卜汁中的胡萝卜素，并进行了精密度，回收率试验和ＧＢ１２３８９－９０纸层析法进行了显性差异检验，得到了较满意结果。此方法可专用于胡萝卜汁中的胡萝卜素含量的快速测定。     

Progress of AFM single-cell and single-molecule morphology imaging

Atomic force microscopy (AFM) can probe single living cells and single native membrane proteins in natural fluid environments with label-free high spatial resolution. It has thus become an important tool for cellular and molecular biology that significantly complements traditional biochemical and biophysical techniques such as optical and electron microscopy and X-ray crystallog-raphy. Imaging surface topography is the primary application of AFM in the life sciences. Since the early 1990s, researchers have used AFM to investigate morphological features of living cells and native membrane proteins with impressive results. Steady improvements in AFM techniques for imaging soft biological samples have greatly expanded its applications. Based on the authors’ own research in AFM imaging of living cell morphologies, a review of sample preparation procedures for single-cell and single-molecule imaging experiments is presented, along with a summary of recent progress in AFM imaging of living cells and native membrane proteins. Finally, the challenges of AFM high-resolution imaging at the single-cell and single-molecule levels are discussed.