Plasma enteroglucagon,peptide YY and gastrin in rats deprived of luminal nutrition,and after urogastrone-EGF administration. A proliferative role for PYY in the intestinal epithelium?

Intestinal tissue mass was significantly reduced throughout the gastrointestinal tract (p<0.001) of=" intravenously=" fed=" (tpn)=" rats.=" urogastrone-epidermal=" growth=" factor,=" (uro-egf),=" reversed=" these=" changes.=" although=" plasma=" enteroglucagon=" and=" gastrin=" levels=" showed=" a=" small=" increase=" with=" uro-egf,=" this=" was=" far=" less=" than=" the=" gut=" tissue=" weight=" change,=" suggesting=" that=" it=" was=" unlikely=" that=" they=" were=" involved=" in=" modulating=" the=" proliferative=" response=" of=" the=" intestine=" to=" uro-egf.=" peptide=" tyrosine=" tyrosine=" (pyy)=" levels=" were=" however=" significantly=" increased=" by=" uro-egf,=" indicating=" that=" pyy=" may=" possibly=" have=" a=" role=" in=" the=" modulation=" of=" intestinal=" cell=">We thank the Cancer Research Campaign for their financial assistance and acknowledge the technical assistance of Mr W. Lenton.     

The use of 5-fluorocytosine and ketoconazole in the culture of the erythrocytic stages ofPlasmodium falciparum and some tumor cell lines

Summary In vitro culture systems are often contaminated by bacteria and fungi. It is therefore often necessary to supplement culture media with agents such as penicillin/streptomycin, gentamycin or amphotericin B. The latter cannot be used in the in vitro culture of erythrocytic stages ofP. falciparum, and thus anti-fungal agents have not been regularly used in this system. We describe the prophylactic use of 5-fluorocytosine (5-FC) and ketoconazole (KTZ) in tissue cultures at concentrations up to 300 and 10 g/ml respectively which have no effect on the growth ofP. falciparum (FCR-3 strain). A melanoma cell line (C32) and a line of uterine carcinoma (C41) were also unaffected by similar concentrations of 5-FC and KTZ. When dissolved in complete culture medium (RPMI 1640) with 10% human plasma, the minimum inhibitory concentration of 5-FC for a susceptible strain ofCandida remained below 2 g/ml. These experiments suggest that 5-FC (at 50 g/ml) alone or in combination with KTZ (at 1 g/ml) is a useful addition to the armamentarium of antimicrobials available to the tissue culture biologist for a variety of cell culture systems.     

Hela细胞中突变PSF蛋白对细胞增殖迁移及可变剪接的影响

PSF作为真核细胞中的抑癌蛋白,在Hela细胞发生基因突变导致其蛋白功能改变.为了阐明突变体PSF蛋白在肿瘤细胞的作用,本文分别采用siRNA干扰、细胞生长曲线、细胞划痕等实验检测muPSF对Hela细胞增殖及迁移的影响,半定量PCR实验分析PSF调控的下游靶基因的可变剪切情况.研究结果显示,当通过siRNA干扰muPSF的表达后Hela细胞的增殖迁移能力下降,高表达突变体PSF可增强Hela细胞的增殖与迁移,半定量PCR实验分析PSF下游调控基因显示muPSF可以改变增殖和迁移相关基因的可变剪接形式.因此,我们的实验证明,Hela细胞中muPSF通过调控下游靶基因的可变剪切影响Hela细胞的增殖和迁移能力.     

Central electron-enriched NO-FeN4 sites as superior acidic oxygen reduction reaction electrocatalysts for proton exchange membrane fuel cells

Developing nobel-metal-free catalysts, especially for iron-nitrogen on carbon (FeNC) materials, has been an urgent demand for wide applications of proton exchange membrane fuel cells (PEMFCs). However, the inferior oxygen reduction reaction (ORR) activity of traditional iron-nitrogen sites in acidic conditions seriously impedes the further improvement of their performance. Herein, we synthesized FeN₄ with NO (nitric oxide) group axial modification (denoted as NO-FeN₄) on a large scale through a confined small molecule synthesis strategy. Benefitting from the strong electron-withdrawing effect of the NO group, the central electron-rich FeN₄ site exhibits ultrahigh ORR activity with a three times higher mass activity (1.1 A·g?1 at 0.85 V) compared to the traditional FeN₄ sample, as well as full four-electron reaction selectivity. Moreover, the PEMFC assembled with the as-prepared electrocatalyst also exhibits a greatly enhanced peak power density (>725 mW·cm?2). This work provides a new approach to rationally design advanced M-N_x nonnoble electrocatalysts for the ORR.     

miR-194-5p通过Wnt5a抑制肝星状细胞活化

为研究miR-194-5p对肝星状细胞(HSCs)活化的影响及作用机制,采用CCK-8、β-半乳糖苷酶染色、Transwell、划痕、集落形成实验和RT-qPCR、Western blot分别检测miR-194-5p对LX-2细胞生物学特性、细胞活化标志物和靶基因表达的影响,并用生物信息学和双荧光素酶报告实验确定miR-194-5p靶基因.结果显示：miR-194-5p抑制LX-2细胞增殖、细胞集落形成、迁移能力以及LX-2细胞中活化标志物的表达,促进LX-2细胞衰老;Wnt5a为miR-194-5p的直接靶基因.研究表明miR-194-5p通过靶定Wnt5a抑制LX-2细胞活化,miR-194-5p和Wnt5a可能是治疗肝纤维化新的靶点.     

扩散层孔隙率对平行流场 PEMFC 性能影响研究

为了研究扩散层孔隙率对质子交换膜燃料电池的性能影响,采用计算流体动力学商业软件 ANSYS Fluent在不同扩散层孔隙率(0. 3、0. 5、0. 7)的条件下,对传统平行流场和斜坡平行流场的性能曲线、气体浓度分布、液态 水分布进行数值模拟分析;结果表明:在高电位下各案例对应的性能差异较小,在中低电位性能差异较大,随着扩散层孔隙率越大,质子交换膜燃料电池性能越好,且孔隙率在 0. 3~ 0. 5 时电流密度增长率最大,最大可达 9. 03%;当扩散层孔隙率较高时,有利于反应气体穿过扩散层,使得催化层氧气浓度增大,促进了燃料电池内部的电化学反应;随着扩散层孔隙的增大,能够更有效地促进反应气体的传输,流道内水含量越高,越有利于液态水的排出;相比传统平行流场,斜坡平行流场电池性能更好,氧气分布更均匀,流道中气体流速更大,排水效果更好,且孔隙率为0. 7 时电流密度增长率最大,最大可达 28. 79%。     

胞映射及其绘图方法

简要地说明了胞映射法分析了非线性系统全局性态的理论和方法；提出了一种绘图数据的压缩存储算法。这种算法可以节省大量存储空间和传送数据所需的时间，为胞映射法解决工程实际问题提供了条件，根据图形情况可节省存空间１０－１０００倍，文中附有两个数值实例。     

Classification of Cancer Cells Using Neural Networks in Combination with Expert Experience

ＣｌａｓｓｉｆｉｃａｔｉｏｎｏｆＣａｎｃｅｒＣｅｌｓＵｓｉｎｇＮｅｕｒａｌＮｅｔｗｏｒｋｓｉｎＣｏｍｂｉｎａｔｉｏｎｗｉｔｈＥｘｐｅｒｔＥｘｐｅｒｉｅｎｃｅＳｈｉＫｕｉｆａｎ（史奎凡），ＣｈｅｎＹｕｅｈｕｉ（陈月辉），ＤｏｎｇＪｉｗｅｎ（董吉文）Ｄｅ...     

铝电解槽槽膛内形在线显示仿真软件的研究与开发

利用Ｗｉｎｄｏｗｓ操作系统的优势，结合数学模型的研究与结果，对铝电解槽槽膛内形在线显示的可视化仿真软件进行了设计研究；并用ＢｏｒｌａｎｄＣ＋＋成功地开发出了一套具有良好的Ｗｉｎｄｏｗｓ用户界面风格的软件．该软件能根据用户要求同时在线解析和显示多个不同槽的槽膛内形及其特征值等；并附有在线帮助功能．经实验室初步模拟实验研究和现场实测数据对比表明，模型和软件均能较好地反映实际槽况，运行稳定可靠．是铝电解槽智能模糊控制系统的一个重要组成部分