格氏栲自然保护区常绿阔叶林群落的数量分类

基于对群落22个样地的调查,以群落样地中乔木层树种的重要值为指标,采用纸条排队法、群落相似系数分类法、最近邻体法和组平均法对格氏栲自然保护区常绿阔叶林群落进行数量分类。结果表明:4种分类结果基本相似,格氏栲自然保护区常绿阔叶林群落样地可分为格氏栲群系、米槠群系、甜槠群系、刨花楠群系、沉水樟群系、观光木群系和闽楠群系等7个群系,并论述了各群系的群落学特征,各群系基本处于稳定的顶极阶段。     

Rhizobium qilianshanense sp. nov., a novel species isolated from root nodule of Oxytropis ochrocephala Bunge in China

During a study of the diversity and phylogeny of rhizobia isolated from root nodules of Oxytropis ochrocephala grown in the northwest of China, four strains were classified in the genus Rhizobium on the basis of their 16S rRNA gene sequences. These strains have identical 16S rRNA gene sequences, which showed a mean similarity of 94.4 % with the most closely related species, Rhizobium oryzae. Analysis of recA and glnA sequences showed that these strains have less than 88.1 and 88.7 % similarity with the defined species of Rhizobium, respectively. The genetic diversity revealed by ERIC-PCR fingerprinting indicated that the isolates correspond to different strains. Strain CCNWQLS01^T contains Q-10 as the predominant ubiquinone. The major fatty acids were identified as feature 8 (C18: 1ω7c and/or C18: 1ω6c; 67.2 %). Therefore, a novel species Rhizobium qilianshanense sp. nov. is proposed, and CCNWQLS01^T (= ACCC 05747^T = JCM 18337^T) is designated as the type strain.     

Root Pressure of Tropical Lianas and Their Relationships with Phylogeny and Environments

Lianas usually possess large vessels, which are vulnerable to cavitation. Root pressure may play an important role in embolism repair of vessels. However, little is known about the generality of root pressure in tropical lianas. To characterize root pressure of lianas in tropical rainforests, we used pressure transducers to measure root pressure in the rainy and dry seasons for a total of 32 lianas from 14 families common in Xishuangbanna. We further analyzed the associations of maximum root pressure with phylogeny and of transient root pressure with environmental factors. We found that all lianas we selected had root pressure, with maximum root pressure ranging from 2-138kPa. In the dry season, about 72% (23 species) of the lianas had relatively low root pressure (<15kPa) and maintained positive throughout the day. This may be important for water balance for roots and basal stems of lianas. There were three types of diurnal changes in liana root pressure. In Type I, root pressure had obvious diurnal variation in the dry and rainy seasons. In Type II, root pressure did not show obvious diurnal variation in the dry and rainy seasons. In Type III, either in the dry or in the rainy season, root pressure showed obvious diurnal variation. Root pressure varied substantially among lianas, with lianas from two families, Fabaceae and Vitaceae, usually having relatively higher root pressure, suggesting that phylogeny may influence root pressure. Transient root pressure closely responded to photosynthetically active radiation. In most cases, however, it was not related to rainfall and vapour pressure deficit. These results suggest that the associations of liana root pressure with environments need further investigation.     

phbA基因对拟南芥质体转化及花粉表型分析

采用来源于产碱杆菌(Alcaligenes eutrophus)的PHB合成酶基因phbA,经PCR扩增后,将验证正确的phbA插入到烟草质体表达载体pBio3-GFP中,取代载体中的gfp,形成prrn-phbA-aadA-TpsbA-ter表达盒,得到质体表达载体pCTHBA,通过基因枪介导,用包裹有质粒pCTHBA的金粉子弹轰击拟南芥无菌苗叶片,经壮观霉素筛选后获得拟南芥抗性植株12株;PCR验证初步表明,phbA已整合进拟南芥的质体基因组中;对转基因拟南芥植株的花器官表型和花粉显微观察表明,phbA基因在拟南芥中得到表达,显现出雄性不育的性状.     

螺旋CT三维重建技术在胫骨平台骨折的诊疗应用分析

目的探讨螺旋CT三维重建在胫骨平台骨折中的临床应用。方法回顾性分析2007-2008年55例胫骨平台骨折病例．手术前均常规行X线摄片,行螺旋CT三维重建并与术中所见对照。结果所有病例螺旋CT三维重建明确地显示了骨折,并在骨折的分型和关节面碎裂情况的描述上较平片优越,与手术中所见一致。结论CT多种成像后处理技术可清晰显示骨折的部位、骨折线的走行方向、骨质碎裂程度和移位的距离以及关节面塌陷情况等,对术前分型、制订手术治疗方案具有重要的参考价值。     

可持续的污水处理过程与展望

传统上,污水在处理过程中其所含有的能源和营养物质等也被消耗了。可持续的水处理不仅包括污水无害化处理,还包括能源和营养物的综合回收利用。综合论述了可持续的污水处理概念、理论、方法和污水处理过程中物质回收技术的发展。     

鸡生长激素基因5′端部分调控区的克隆分析

利用PCR技术扩增、克隆、测序了7个跨越不同生长速度的鸡品种(系)的生长激素(GH)基因的5′端部分调控区。这7个品种(系)分别为:高生长速度的宝罗肉鸡父本;较高生长速度和一定的产蛋性能的宝罗肉鸡母本;肉蛋兼用型的芦花鸡;中等生长速度和中等体重的蛋鸡品种洛岛红和农大褐;生长速度较慢体重较轻的蛋鸡品种北京白鸡和生长速度很慢但又不是矮小型的地方品种丝毛乌骨鸡。所扩增的片段长度为760bp,包括了转录起始位点5′端侧翼区的473bp、两个可能的TATA框、组织特异性转录因子结合位点、第一个外显子和部分第一内含子。所有克隆的鸡GH基因5′端调控区与Tanaka发表的序列相比,均在-34碱基的位置上缺失一个胞嘧啶C,在 160与 161碱基之间多1个胸腺嘧啶丁,在 175碱基的位置上出现了以腺嘌呤A替换了鸟嘌呤G的情况。7个品种(系)之间的比较显示,鸡GH基因启动区具有极高的保守性,在具有不同生长速度的鸡品种间不存在任何差异。说明鸡的不同生长速度和成年体重,不是由于生长激素5′调控区变异造成的。鸡生长激素基因表达的差异可能受到内含子或3′端侧翼序列的影响。     

东北斑蚜科及蚜科新种及新纪录(同翅目:蚜总科)

本文记述我国东北地区斑蚜科一新种和蚜科一新种及一新纪录种。模式标本存中国科学院动物研究所。 椴绵叶蚜Sinishivaphis tilisucta Zhang新种(图1) 有翅孤雌蚜 活体灰绿,被白粉。体背及足股节、胫节有明显蜡片。腹部背片Ⅷ有一中瘤。喙不达中足基节。翊脉镶黑边如图所示。毛数:头背10,前胸背10,腹部背片Ⅰ—Ⅶ各4,Ⅷ6或7,触角节Ⅰ3,Ⅱ3或4,Ⅲ25—29,Ⅳ14—18,Ⅴ4或5,Ⅵ3+0,顶端3或4,喙节Ⅳ+Ⅴ10,附节Ⅰ7,尾片7,尾板15或16。触角次生感觉圈有睫:     

超低频脉冲磁场抑制癌瘤和提高细胞免疫功能的实验研究

在报道用电子显微镜观测超低频脉冲磁场(峰值磁场0.6～2.0T,磁场梯度10～100T·m^-1,脉冲宽度20～200ms,重复频率0.16～1.34Hz)抑制鼠S-180肉瘤和加强免疫细胞溶癌作用以后,报道了用Faulgen染色法测定肉瘤细胞核的DNA倍性,和用电镜技术和细胞结构的体视学分析磁场对癌细胞形态的影响,观测到磁场影响癌细胞的代谢:磁场使癌细胞的恶性程度降低,抑制其高速和异形生长;磁场抑制癌细胞的分裂和DNA的复制;磁场提高细胞免疫功能,加强淋巴细胞、浆细胞反应.     

两阶段搅拌转速控制策略发酵生产聚唾液酸

目的:优化聚唾液酸发酵过程的搅拌转速.方法:比较不同搅拌转速对大肠杆菌Escherichia coli K235分批发酵生产聚唾液酸过程的影响.结果:根据发酵前、后期菌体细胞比生长速率和聚唾液酸比合成速率达到最大值所需搅拌转速的不同,提出了两阶段搅拌转速控制策略:发酵前期(0～15h)控制搅拌转速500r/min,发酵中后期控制搅拌转速700r/min.结论:两阶段搅拌转速控制策略使聚唾液酸产量达到3 966mg/L,比恒定搅拌转速500r/min和700r/min分别提高了31.8%和49.3%.将两阶段搅拌转速控制策略与分批补料发酵技术结合,聚唾液酸产量提高到5 108mg/L,山梨醇的转化率达到0.12g/g.