树木枯落叶在河流水体中的分解及氮、磷释放动态

以郑州市东风渠为试验点,选择法国梧桐枯落叶为对象,利用分解袋法,在为期39d的分解试验中,研究了落叶分解及氮、磷的动态变化。结果表明:分解过程中,样品质量变化呈现持续减少的趋势,试验期间质量损失约11.6%,理论完全分解时间约8.21a。在生物和非生物因素共同作用下,落叶中的氮、磷含量变化波动较大。试验初期(0-9d),氮含量快速降低;然后又表现为逐渐升高,在分解后期(29-39d)又呈现下降趋势。落叶中磷含量在分解初期呈下降趋势,随后又逐渐升高,到分解中期,磷含量又表现为先下降后升高的趋势,至分解末期,再次出现下降。落叶中氮素的累积指数NAI和磷素累积指数PAI整体上表现出以释放为主。随分解时间,大体上呈现释放-积累-再释放的规律。     

解决种子重复鉴定问题探析

在现行体制下,受利益驱动,寻求对自己有利的种子鉴定结论成为种子案件当事人的核心追求,从而引发了种子重复鉴定。本文分析了导致种子重复鉴定的原因并论述了解决种子重复鉴定构想。     

填充型烤烟标准化生产技术规程

本规程规定了填充型烤烟生产的品种选择、育苗移栽、打顶抹权、施肥、病虫害防治、采收和烘烤等技术要求。     

千阳县新优品种桑园的建设之我见

好地栽好桑,好桑养好蚕,合理规划良桑品种布局,加强肥培管理,加快桑园流转,培育强村大户,发挥新优桑树品种在千阳县的丰产性能。     

ISSR Analysis on Genetic Diversity of the 34 Populations of Oryza meyeriana Distributing in Yunnan Province,China

The genetic diversity of the 34 populations of wild rice Oryza meyeriana Baill.distributed in Yunnan Province,China was analyzed using 13 inter-simple sequence repeat(ISSR)markers.A total of 168 bands were amplified,of which 135 polymorphic bands were discovered and the percentage of polymorphic bands(PPB)was 80.36%.A genetic diversity was revealed as Nei's gene diversity(H)=0.2666 and Shannon information index(η)=0.4028 at population level.The 34 populations were divided into different groups based on administrative regions,latitude and longitudes,river areas,altitudes of their origins,and their indexes such as Na(number of alleles),Ne(effective number of alleles),H,I and PPB were calculated.Richer genetic diversity was found in the wild rice populations distributed in Simao Prefecture than that in Lingcang Prefecture or Xishuangbanna Prefecture whereas the least genetic diversity was in Baoshan Prefecture or Dehong Prefecture.Rich genetic diversity was also discovered in the wild rice populations originated from higher than 710 m altitude around the middle and lower reaches of the Lancang River belonging to the Pacific Ocean drainage system.The 34 populations could be classified into two groups,one group covered the wild rice distributing in Simao Prefecture only while the other group covered ones in Lingcang,Xishuangbanna and Oehong Prefectures.The issue on how to effectively conserve the wild rice germplasm was discussed.     

鸡大肠杆菌性腹膜炎的防治

鸡大肠杆菌病是一种条件性疾病,表现有很多形式,其中大肠杆菌性腹膜炎是其中比较常见的形式,其危害也比较严重.     

GABAergic神经元在BARREL和VPM区组织结构及形态特点的研究

啮齿类以胡须为感觉器官,通过其摆动获取物体质地和空间位置信息。在老鼠的每一侧嘴部,有5列水平排布的机械感受器,位于胡须下面的囊泡中。胡须摆动可打开机械型离子通道,产生动作电位,经传出纤维传入位于脑干的三叉神经节中,从而使三叉核团的谷氨酸型突触产生兴奋。三叉丘脑核团在三叉核团处形成躯体代表区,称为“barrelettes”。接着脑干中的这些神经元又将信息传入丘脑的Ventral poslerior medial（VPM）核团,     

Effects of up-regulation of c-myc expression on U937 cell line

AIM:To establish a human monocytic　leukemia cell line U937 stably expressing c-myc gene and to investigate the biological characteristics of this cell line. METHODS:The recombinant plasmid MSCV-c-myc-IRES-GFP (MMIG) was constructed. MMIG and MSCV-IRES-GFP (MIG) were used to package the viruses for infecting U937 cells. Fluorescence-activated cell sorter (FACS) was used for sorting U937/GFP and U937/MYC cells. The GFP-positive cells were detected by fluorescence microscopy and FACS. The protein expression of c-Myc, survivin, X-linked inhibitor of apoptosis protein (XIAP) and Bcl-2 was detected by Western blotting. Cell proliferation was evaluated by MTT assay. Propidium iodide (PI) staining was used to determine the cell cycle distribution. Self-renewal ability was observed by colony- forming assay. RESULTS:The GFP expression in the cells infected with MIG or MMIG virus was observed under fluorescence microscope. The green fluorescent rate of the cells infected with MIG was 26.0%, while that of the cells infected with MMIG was 27.7%. The protein expression of c-Myc in MMIG-infected U937 cells was higher than that in MIG-infected cells. After sorting, the green fluorescent rates of U937/GFP and U937/MYC cells reached 98.7% and 93.7%, respectively. The protein expression of c-Myc in U937/MYC cells was higher than that in U937/GFP cells. In addition, survivin, a downstream protein of c-Myc, was up-regulated, while the protein expression of XIAP and Bcl-2 remained unchanged. Cell cycle analysis showed that the percentage of the cells in S phase increased in U937/MYC cells. Moreover, the proliferation and colony-forming ability of U937/MYC cells were also enhanced. CONCLUSION: U937/MYC cell line stably expressing c-myc gene was successfully established. c-Myc may increase cell viability via enhancing the expression of anti-apoptotic protein survivin, the cell cycle transition and the self-renewal ability.     

沙木蓼硬枝扦插育苗试验

本文简述了沙木蓼硬枝扦插时，采用不同基质、不同穗长和不同生长素的对比试验效果。结果表明，基质以耕作土和沙子混合，比例8：2的效果良好；三种生长素NAA（吲哚乙酸）、IAA（萘乙酸）和GGR（生根粉）对苗木生长都有促进作用，浓度以100～200mg／L为宜；插穗适宜长度为8～12cm。