三氯生的应用和检测方法研究进展

三氯生(2,4,4-三氯-2-羟基-二苯醚)是一种广谱抗菌剂,具有高效杀菌作用,可杀死金黄色葡萄球菌、大肠杆菌和白色念球菌,对化脓性球菌、肠道致病菌和真菌具有消毒作用,同时对乙型肝炎病毒等病毒也有抑制作用,以往被认为对环境和人体是高度安全的[1],因此得到广泛应用[2,3],如用于高档日化用品的生产(添加到香皂、漱口水、化妆品、洗涤用品、头发定型水等个人护理品中充当杀菌消毒剂)、饮食行业器械     

几种受体阻断剂对新疆细毛羊回盲结肠综合肌电的调控作用

绵羊回肠后部、盲肠和结肠初袢平滑肌的Ｍ受体，对综合肌电的峰电发生和增强起着调控主导作用。α抑制型受体起着与Ｍ受体相反的效应，Ｈ１受体对这些部位综合肌电的峰电活动也有较明显的增强作用，而β受体在以上部位平滑肌中分布的密度较小。     

“中国营养学会第13届全国临床营养学术会议”征文

中国营养学会第13届全国临床营养学术会议将于2011年9月17—19日在杭州召开。征文范围:医院营养科性质和职责定位及临床营养工作管理模式探讨和经验;临床营养治疗规范化管理;临床营养学的基础研究;各类疾病的肠内及肠外营养支持研究和实践;饮食营养以及     

幼鼠小肠缺血-再灌注肠组织的形态学观察

目的:观察幼鼠小肠缺血-再灌注(ischemia/reperfusion,I/R)肠组织形态学变化。方法:将32只4周龄(Sprague Dawley,SD)大鼠随机分成2组即假手术组(Sham组)和缺血-再灌注组(I/R组),每组各16只。Sham组仅暴露腹腔脏器,不作任何干预;I/R组经阻断肠系膜上动脉60 min后恢复血供,于再灌注30、60、90、120 min每组动物各处死4只取小肠组织进行组织学Chiu’s评分,结果进行单因素方差分析和组间t检验。结果:Sham组肠组织形态正常;I/R组小肠组织发生了明显的缺血和炎症反应并随再灌注时间延长而加重,各观察时间点组织学评分在组间比较差异均有统计学意义,各值在I/R组高于Sham组(P<0.05)。结论:幼鼠肠I/R导致肠组织病理损伤并随再灌注时间延长而加重。     

石油烃降解菌培养基组分和条件优化

从新疆油田油井旁土样富集、筛选得到一株高效石油烃降解菌HL-6,经初步鉴定为红球菌属（Rhodococcus sp.）．研究表明,使用乙醇作为碳源制备液体种子液是可行的,之后采用单因素试验设计先后对菌株生长的培养基组分及生长条件进行了优化．结果表明,菌株HL-6的最适生长条件为：碳源（柴油）浓度为0．5％、氮源选择（NH4）2SO4浓度为8g／L、磷源为KH2PO4：Na2HPO4摩尔比为3：1、酵母粉浓度为0．03g／L、培养时间为3d、培养温度为20℃、pH=7．6、装液量为30mL、接种量为1．5％、摇床转速为150rpm．验证实验和预期一致,优化后降解率达到89．80％,比最初的78．50％提高了14．4％．     

为什么不能边吃饭边看书

有些人喜欢边吃饭边看书，或者边吃饭边说笑。这样的习惯都很不好。为什么呢？因为会分散大脑的注意力，使供应消化器官的血液相对减少，影响肠胃的消化功能。     

人类过度捕鱼 海豚饥肠辘辘

以色列海域的樽鼻海豚正在变得越来越瘦骨嶙峋，这很可能是因为它们长期吃不饱肚子的缘故。而它们之所以会挨饿，是由于人类过度捕捞它们赖以为生的鱼类，在过去的6年里，科学家一直在对生活在这一水域的74头樽鼻海豚进行跟踪拍照。     

Cloning and analysis of the antagonistic related genes of <Emphasis Type="Italic">Enterobacter cloacae</Emphasis> B8

To understand the antagonistic mechanism of the broad spectrum antagonistic Enterobacter cloacae B8,Tn5 transposon-mediated mutagenesis is performed using suicide plasmid pZJ25. Two mutant strains that lost antagonistic character are isolated. Tagging with kanr gene on Tn5,an antagonistic related DNA fragment, the F fragment, right of the Tn5 insertion site is cloned in a plasmid named pTLF,from one of the mutant strains B8F. The 733 bp F fragment is then sequenced after subcloning. Genomic DNA of the original B8 strain is isolated, digested with Pst I and ligated to Pst I cassette. DNA fragments left and right of the F fragment are amplified from the Pst I cassette library using cassette primer and specific primers designed according to known sequence. 1106 bp sequence left of the F fragment and 664bp sequence right of the F fragment are finally obtained. Bioinformatics analysis shows that the contig assembled from the sequences of the cloned antagonistic related DNA fragments of B8 encodes three ORFs and is homogeneous to admM,admN and admO genes of Pantoea agglomerans andrimid biosynthetic gene cluster (AY192157). The ORF, named anrF gene which encodes a polyketide synthase, knocked out by Tn5 insertion, is a homology of admM and the insertion site of Tn5 is at 214 bp upstream of the stop codon. It is concluded that the anrF gene is a gene related to the antagonistic activity of E. cloacae B8, and speculated that the antagonistic substance produced by B8 is an andrimid.     

Permeation of vanadium（Ⅲ, Ⅳ, Ⅴ）-dipicolinate complexes across MDCK cell monolayer and comparison with Caco-2 cells

The permeation and eytotoxicity of three insulin-mimetic vanadium（Ⅲ, Ⅳ, Ⅴ）-dipicolinate complexes were studied using the MDCK cell monolayer in comparison with the Caeo-2 cells. On MDCK cell monolayer, the apparent permeation coefficients （Papp） were estimated to be （7.5±1.0）×10^-6, （1.0±0.2）×10^-6, （1.7±0.4）× 10^-6cm/s for V（Ⅴ）, V（Ⅵ）, and V（Ⅲ）-dipie complexes, respectively. The permeability of V（Ⅴ）-dipie complexes is much better than the others, which is in agreement with its better hypoglycemie effect in animal tests. On Caeo-2 cell monolayer, Papp were found to be in the range of 1-3×10^-6 ends and not to be affected by excessive amounts of dipieolinate ligand. By contrast, the permeability in the AP→BL direction across the MDCK monolayer increased greatly in the presence of free ligands, suggesting existence of active transport mechanism of vanadium complex anions on the MDCK cells. The eytotoxieity of the three complexes was found similar and the IC50 were measured in the range of 0.6-0.9 mmol/L for MDCK cells and 1.6--2 mmol/L for Caco-2 cells. The cytotoxicity of three vanadium complexes was conceivably in consistence with their permeability, suggesting that the toxicity, permeation and cellular metabolism of vanadium complexes are closely related.