He—Ne激光对君子兰幼果和胡萝卜根的愈伤组织形成及生长的影响

利用6mv的He—Ne激光器,每天对君子兰幼果、胡萝卜根的外植体辐照5分钟,连续辐照20天,对愈伤组织的形成和生长有一定的促进作用。但同样条件下,辐照10分钟,对君子兰幼果,胡萝卜根的愈伤组织形成和生长都有明显的抑制作用。     

对高中生物实验操作能力的考查

生物学是一门实验科学,实验和观察是生物科学研究的重要方法。在生物教学中有十分重要的地位。高中生物学是初中生物学知识的综合、概括和提高,它侧重于生命活动的共同规律的研究。因此教师要组织学生做好实验,以培养学生实事求是的科学态度,增进学生学习生物学的兴趣,更好地理解生物学知识,掌握实验基本技能,发展他们的智力和动手能力。那么如何加强高中生物实验操作等能力的考查呢?     

EFFECTS OF VASOACTIVE INTESTINAL PEPTIDE ON ACTIVITIES OF SUCCINIC DEHYDROGENASE AND ALKALINE PHOSPHATASE IN RAT HEPATOMA CELLS

Using cytochemical method,microspectrophotometry and image analysis,effects of va-soactive intestinal peptide(VIP)on activities of succinic dehydrogenase(SDH)and alkalinephosphatase(ALP)in rat hepatoma cells were studied in vitro.The results showed that thehepatoma cell expressed potent positive reactions of SDH and ALP,the positive positionswere located at the cell membranes and/or cytoplasm.Having been treated with VIP,ALPdecreased obviously in activity(P<0. 01,compared with hepatoma cells untreated by VIP).The sites of ALP activty were chiefly located at the cell membranes,particularly at the cell-cell contacts.Cultured rat hepatoma cells had intensive SDH activity in their cytoplasm.Compared with untreated eclls,there was no marked difference in the intensity of SDH activ-ity in VIP-treated hepatoma cells(P>0.05).     

23个实验小鼠和大鼠近交系的保种研究

从1985年开始,陆续从国外实验动物著名机构引进常用近交系小鼠共23个品系(亚系和亚群)。在多年来保种繁殖过程中,根据修饰平行线系统选择留种动物,同时对动物进行全兄妹近亲交配繁殖,保持完整的谱系记录,控制饲养环境条件,成功地保持了绝大多数品系。同时对多数品系的繁殖性能和体重增长进行了观察,为这些品系的实验应用提供基本参数。     

基于转录组测序的宁夏枸杞不同品种果实活性成分合成差异表达基因分析

为探究不同品种宁夏枸杞果实活性成分生物合成相关基因的表达水平,筛选关键差异表达基因(differentially expressed genes,DEGs),揭示宁夏枸杞品种间活性成分含量差异的分子机制,本研究采用Illumina NovaSeq 6000高通量测序技术,对宁夏枸杞‘宁杞1号’和‘宁杞7号’青果期、转色期及成熟期果实进行转录组测序,比较2个品种果实不同发育期相关基因表达谱的变化。结果显示:转录组测序共获得811818178条clean reads,有121.76 Gb有效数据。‘宁杞1号’和‘宁杞7号’在青果期、转色期和成熟期差异表达基因分别有2827、2552和2311个;分别有2153、2050和1825个差异基因在基因本体论(gene ontology,GO)、京都基因与基因组百科全书(Kyoto encyclopedia of genes and genomes,KEGG)富集分析和同源蛋白簇(clusters of orthologous groups of proteins,KOG)分析等6个数据库中被成功注释。青果期、转色期和成熟期果实的差异表达基因,在GO数据库分别有1307、865和624个被富集到生物学过程、细胞组分及分子功能3个部分中;KEGG通路富集结果均集中在代谢途径、次生代谢物生物合成和植物-病原互作过程;在KOG数据库,3个发育期分别注释了1775、1751和1541个差异表达基因。对注释的基因进行PubMed数据库检索,在青果期、转色期和成熟期分别筛选到与枸杞活性成分合成相关的差异表达基因18、26和24个,这些基因主要参与类胡萝卜素、类黄酮、萜类、生物碱和维生素等代谢途径。选取7个差异表达基因进行RT-qPCR验证,结果与转录组测序数据表达趋势一致。本研究从转录水平为不同品种宁夏枸杞活性成分含量差异提供了初步证据,为进一步挖掘枸杞活性成分生物合成的关键基因及解析其表达调控机制提供了研究基础。     

QUALITATIVE ANALYSIS OF BIOECOLOGY DIFFERENTIAL SYSTEM

In this paper, the author studies the quartic bioecology differential system:Here n and q are positive constants, l、m and p are constants. The author also proves some theorems of existence and uniqueness of limit cycles of this differential system.     

DISCOVERY OF VERTEBRATE FOSSILS AND PALEOLITHIC ARTIFACTS IN DANJIANG SUBMERGING AREA AND ITS IMPLICATIONS

IntheareatobefloodedinthesecondengineeringstagefortheDanjiangreservoir,wediscovered16vertebratefossillocalitiesand52Paleolithicsitesin1994,andcollected603artifactsandmanyfossils.Ofthel6new1yfoundvertebratefossillocalities,threearereptilesitesrepresentedbydinosaureggsandlimbbones,andl3producemamma1s,including4Pale0gene,2Ne0geneand7Quaternarysites'ThemammalianlocalitiesareofPale0cene,Eocene,EarlyMiocene,andPli0ceneorEarlyPleistocene,MiddleandIntePleistocene,respectively.Theyfillinsomestrat…     

中国北方黄土地层中的哺乳动物群及在磁性地层中的位置

本文研究了中国黄土地层中有确切层位的哺乳动物化石记录,并进行了生物地层学与磁性地层学对比,将黄土地层中的动物化石归纳成如下哺乳动物群：早更新世（2．50─0．73Ma）：午城动物群（2．50─1．20Ma）、公王岭动物群（1．20─1．10Ma）和阳郭动物群（1．10─0．90Ma）、中更新世（0．73─0．13Ma）：陈家窝子动物群（0．73─0．40Ma）;晚更新世（0．13─0．01Ma）：柔远─靖远动物群（0．13─0．01Ma）;全新世（0．01Ma─Rec）:半坡动物群。结果表明：早更新世许多森林习性的化石动物虽然反映出气候较第三纪的寒冷,但比后期温暖湿润。中更新世出现了较多的草原、干旱草原习性的动物,气候更为寒冷干旱,森林逐渐减少或消失,草原或干旱草原得到发展;晚更新世出现的沙鼠、跳鼠等动物,表明气候更加寒冷、干旱,部分地区甚至沙化。     

THE STABILITY OF INTERVAL MATRICES

I．IntrodutionInthepaper厂1］al。d［2】．themeasureofmatrixAandsystemofma－trlcesA（t）（t＞t。）wasInvestlgat叨respective！y．Inthispaper,weIntroducethecone叩tofthemeasureforIntervalmatrlcesalldstudythestabilityofIntervalmatrlcesbyuslllgthisconcept．I。etthesystemofmatrixA（l）一（a;,（t》beaplecewlsecolltllltjotlsfunctionmatrix．Inthepaper［2］thefollowingrelatlol。sh,pIssaidtobethemeasureoftilesystemofnlatrlcesA（t）,a：idweof＞talllthatFOfbfOVlty,W6diSCU88Oillyl,1（A（t））1…     

The Conservation Status of Hong Kong's Tree Flora

1IntroductionHongKongliesonthesouthcoastofChinabetweenlatitudes22?9'-22?TNandlon-gitudesl13?2'Nl14?0'E.ItconsistsofasectionoftheChinesemainland(KowloonandtheNewTerritories,782km2)andnumerousislands,ofwhichthelargestareLantauIsland(142km2)andHongKongIsland(78km2).Thetotalareais1076km2.Thetopographyisextremelyrugged,reaching957matthehighestpoint,TaiMoShah,intheNewTerrito-ries.HongKong'spopulationof6millionpeopleisconcentratedonthelimitednaturalflatland,whichhasbeenextendedbycoastalrecla…