社会隔离对小鼠焦虑水平及神经活动的影响

目的 探究不同饲养条件下小鼠Mus musculus的焦虑行为特征及神经活动特征.方法 对21日龄的雄性CD-1小鼠进行社会隔离(SI)或社会群居(SG)饲养处理2周后,采用经典的焦虑行为范式(高架十字迷宫)进行测试,并同步采集内侧前额叶(mPFC)、内侧杏仁核(MeA)、腹内侧下丘脑(VMH)等脑区的局部场电位(LF...     

Isolation and Structural Analysis of an Acidic Polysaccharide from Astragalus membranaceus （Fisch.） Bunge

A new water-soluble hetero-polysaccharlde, APSID3, was obtained from a hot-water extract of the roots of Astragalus membranaceus （Flsch.） Bunge by DEAE-Sepharose Fast Flow and Sephacryl S-300 chromatography. The molecular weight of APSID3 was estimated to be 5.79 × 10^5 Da. Based on a sugar composlUon analysis, methylatlon analysis, partial hydrolysis and 13C nuclear magnetic resonance experimentation, It was concluded that the minimal repeat unit of APSID3 was composed of one terminal arablnose, one 1,5-1Inked arabinose, one 1,3-1Inked rhamnose, one 1,3,4-1Inked rhamnose, five 1,4-1Inked methyl galacturonates and six 1,4-1inked methyl glucuronates.     

Pre- and post-zygotic reproductive isolation between co-occurring Mussaenda pubescens var. alba and A/I. shikokiana （Rubiaceae）

Reproductive isolation is a fundamental require- ment for speciation and includes several sequential stages. Few studies have determined the relative contributions of pre- and post-zygotic reproductive isolation in plants, especially between relative species with clear differentiation in flower form. To investigate the mechanisms responsible for repro- ductive isolation in sympatric A4ussaenda pubescens var. alba and Mussaenda shikokiana （Rubiaceae） in Guangxi Province, China, we made observations of flowering phenology, patterns of insect visitation, and conducted pollination experiments, including artificial hybridization. The two species had over- lapping flowering times and were pollinated by overlapping pollinators; however, their relative importance differed significantly with M. pubescens visited more commonly by bees and M. shikokiana more frequently by butterflies. Using vegetative and floral characters and molecular evidence based on nuclear ribosomal internal and external transcribed spacer regions we detected seven naturally occurring hybrids among a sample of approximately 125 individuals. Hybrids were characterized by morphologies that most closely resembled their maternal parents based on chloroplast evidence. Studies of artificially synthesized and natural hybrids demonstrated that hybrid seed had very low germination rates and naturally occurring hybrids exhibited pollen sterility. Post-zygotic reproductive isolating mechanisms play a primary role in limiting gene exchange between co-occurring species and maintaining species integrity in areas of sympatry.     

关于种群空间格局分析方法的研究

本文导出了一组基于两个最近个体距离Xs和Xt的空间格局非随机性检验量Cs,t,并通过模拟研究，将它们与Holgate的指标H以及Pielou的指标a进行比较，最后将其应用于两个天然林分的格局分析。结果表明，统计量 C1，t(t=2,3,4)的检测功效高于H而低于a，但Cs,t与总体密度参数无关，比a更具有实有性。     

个体化医疗距离我们有多远？

2011年4月22日，由中国工程院医药卫生学部、中国中医科学院将联合举办“2011年健康医学与个体化诊疗研讨会”在京召开。会议围绕健康医学和个体化诊疗这一重大历史性课题进行了热烈的探讨。     

Isolation of a Tomato Protease that May Be Involved in Proteolysis of 1-Aminocyclopropane-l-Carboxylate Synthase

1-aminocyclopropane- 1-carboxylate （ACC） synthase is a principal enzyme that catalyses the committed step in phytohormone ethylene biosynthesis. Previous evidence indicates that the hypervariable C-terminus of ACC synthase is most likely to be processed proteolytically in vivo. However, the protease responsible has not been identified thus far. In the present study, we detected proteolytic activity against ACC synthase （LeACS2） in tomato （Lycopersicon esculentum Mill.） fruit extract based on a newly established in vitro assay system. Purification of the protease through DEAE, gel filtration and MonoQ chromatography resulted in considerable enrichment of a 64-kDa protein species. Subsequent biochemical analysis of the purified tomato protease revealed that the optimal conditions for its proteolytic activity were at pH 8.0 and at 37 ~C. In addition, the protease activity was blocked completely by the metalloprotease inhibitor 1,10-phenanthroline. The present study represents the first report on the isolation of an ACC synthase- processing protease from plant tissues.     

入侵植物藿香蓟表型可塑性对种间竞争的响应

本文以恶性入侵植物藿香蓟（Ageratum conyzoides L.）与其伴生种紫苏（Perilla frutescens (L.) Britt.）为研究对象,分析不同种间竞争距离下藿香蓟功能性状的表型可塑性。结果显示：（1）较高的藿香蓟初始高度可显著减小其后续的相对株高生长（回归系数β=-0.137）,相对株高生长与其初始高度呈显著负相关,藿香蓟的株高生长速度显著高于紫苏;（2）竞争等级对藿香蓟收获时的地上生物量、比茎长和花蕾强度有显著影响（P <0.05）,在竞争距离为5 cm时,藿香蓟比茎长和花蕾强度显著高于其他组别;（3）竞争的不对称性仅影响藿香蓟的比茎长,初始高度高于藿香蓟的紫苏株数越多,藿香蓟的比茎长就越长（β=3.374）;(4)除高生长,藿香蓟其余7个性状均表现出较高的表型可塑性,变异系数CV值在0.17～0.55。藿香蓟综合表型可塑性在不同竞争距离下存在显著差异,在紫苏-藿香蓟距离为2.5 cm时,藿香蓟表型可塑性指数低,竞争距离为10或20 cm时,可塑性指数显著提高。综合来看,面对紫苏的近距离竞争（2.5 cm）,藿香蓟的生长和繁殖普遍受到抑制,表现为较低...     

山西瘦肉型猪(SD-Ⅲ系)基因组DNA的AFLP检测研究

用分子标记AFLP对山西瘦肉型猪(SDⅢ-系)进行纯度检测,旨在为评价该猪种的遗传特性提供相关参数。实验共用8条引物,对25头猪进行了基因组DNA的分析,共获得171个AFLP标记,单引物获得的标记数在3个~15个之间,群体相似系数为0.928(0.892~0.978);遗传距离为0.072(0.022~0.108)。结果表明:AFLP适宜于基因组DNA遗传结构检测;SDⅢ-系猪纯度较高。