四川乐山市发现较大群的家燕及一例斑头雁留此越冬

2008年1月17日下午4时左右,笔者在四川乐山市水口镇大渡河边发现1只家燕正在河面低空飞行捕食.2008年1月25日西华师范大学杨志松博士在该市岷江边天池村及金灯村一带先后发现5小群家燕,分别为4只、1只、10只、1只和3只;同日,胡杰博士在该市青衣江边(金水湾至乐山高新区江段)也发现2小群家燕,分别为4只和6只.     

莴苣授粉前后中央细胞中钙的分布(简报)

Ca2 作为植物生长发育过程中的必需元素之一,通过特定的时、空分布参与调控植物生长发育的诸多发育过程[1].中央细胞是胚囊中体积最大的细胞,与卵器共同构成雌性生殖单位.在被子植物双受精作用中,卵细胞与一个精细胞融合形成胚,中央细胞与另一个精细胞融合并发育成胚乳,为胚的发育提供营养.     

水果湖湾蓝藻水华的形成及其对东湖影响的评价

东湖是武汉市最重要的湖泊,位于湖北省武汉市武昌区,属中型浅水湖泊,它集饮用水源、旅游、疗养、气候调节、水产养殖和水上运动等多功能于一体[1].因此,东湖水质的好坏与武汉人民的生活密切相关.     

中国栅蛛属2新种记述(蜘蛛目:栅蛛科)

本文记了分别采自云南高黎贡山的栅蛛科栅蛛属Hahnia 2新种:垭口栅蛛,新种S.yakouensis sp.nov.和肾形栅蛛,新种S.reniformis sp.nov..垭口栅蛛后眼列前曲,交媾腔大,扁圆形,交媾孔1个,位于交媾腔下缘,交媾管粗,呈"人"字形下行分成2支再向两侧扭曲.纳精囊有一肓管斜向上伸出,鉴于上述特征而与Hahnia mridulae Tikader,1970不同.肾形栅蛛交媾孔2个,位于生殖厣腹面中央,纳精囊1对,大,肾形,插入器始于生殖球左下方,鉴于上述特征而与Hahnia xinjiangensis Wang et Liang,1989不同. Abstract： The present paper deals with two new species of the genus Hahnia collected from the Gaoligong Mountains Region of Yunnan Province, China: Hahnia yakouensis sp. nov., Hahnia reniformis sp. nov..     

注重发挥博士后科研生力军作用

中国医科大学博士后科研流动站始建1995年。目前学校设有基础医学、临床医学和生物学3个博士后科研流动站。但由于每年国家财力有限,资助名额很少,在有限条件下建立、健全博士后制度,加强对博士后人员的培养,调动博士后人员的积极性是一项重要的研究课题。     

Human Immunodeficiency Virus (HIV) infection model based on triangular neutrosophic cubic hesitant fuzzy number

In this paper,we define the basic concept of triangular neutrosophic cubic hesitant fuzzy number and their properties.We develop a triangular neutrosophic cubic hesitant fuzzy ordered weighted arithmetic averaging (TNCIIFOWAA) operator and a triangular neu-trosophic cubic hesitant fuzzy ordered weighted geometric averaging (TNCIIFOWGA) operator to aggregate triangular neutrosophic cubic hesitant fuzzy number (TNCHFN) information and investigate their properties.Furthermore,a multiple attribute decision-making method based on the TNCHFOWAA operator and triangular neutrosophic cubic hesitant fuzzy ordered weighted geometric (TNCHFOWG) operator and the score function of TNCHFN is established under a TNCHFN environment.Finally,an illustrative example of investment alternatives is given to demonstrate the application and effec-tiveness of the developed approach.     

遗传物质的发现者之一——麦卡锡

1944年,3位科学家艾弗里、麦卡锡和麦克劳德在DNA遗传本质方面的发现是20世纪最重要的发现之一,这个发现打开了生物学革命的大门,从而改变了人类对自然界的看法,这项研究还为1953年沃森和克里克DNA双螺旋结构的发现奠定了坚实的基础,但不幸的是3位科学家都未曾荣获诺贝尔奖.通过介绍麦克林·麦卡锡的科学研究,从而对这项发现的基本状况有一个基本的了解.     

椰子杂种优势及其利用研究进展(综述)

概述了国内外椰子杂交研究情况,并分析椰子杂交种在营养生长、产量、品质、抗性等方面的表现,认为椰子杂交种具有较强的杂种优势,利用前景广阔.     

生命之树与进化模式:导言

One and half centuries ago, Charles Darwin (1859) presented overwhelming evidence and argued that all life on the earth shared common descent, and "from so simple a beginning endless forms most beautiful and most wonderful have been, and are being evolved". Ernst Haeckel (1886) and several of his contemporaries attempted to trace the pattern of descent among all extant and extinct forms in what Darwin referred to as "the great Tree of Life". Ever since then, systematists and evolutionary biologists have been exploring morphological, cytogenetic, chemical, developmental and molecular characters, and actively developing theories and methods to infer phylogenetic relationships among organisms from these characters. This endeavor has been especially stimulated by the rise of molecular biology and the emergence of computer science over the past 50 years. At the beginning of the 21st century, we are presented with an unprecedented opportunity to reconstruct the entire Tree of Life, and further, to study evolutionary processes and mechanisms in the context of a robust phylogenetic framework.     

我国微生态学的奠基人——魏曦

魏曦,字东升,1903年12月25日出生于湖南岳阳一个小职员家庭,父亲任职于邮政局.1914～1921年他在家乡湖滨中学读书,毕业后考入长沙湘雅医学院,学习两年后曾参加北伐军,任第四集团军警卫团三等军医.后退出军队,在长沙广雅中学任教.1928年入设立在上海的中央大学医学院(1932年独立为上海医学院)学习,1933年毕业,获博士学位.     

异育银鲫体内盐酸双氟沙星血浆蛋白结合率的变化与其药代动力学研究

为了研究盐酸双氟沙星(difloxacin, DIF)在异育银鲫体内血浆蛋白结合率的变化及其与药代动力学之间的关系, 实验采用超滤法测定了DIF在异育银鲫体内血浆蛋白结合率, 运用HPLC测定其对应时间点药物浓度, 并分析了血浆蛋白结合率变化对DIF体内处置的影响。实验以感染嗜水气单胞菌的异育银鲫为感染组, 健康异育银鲫为对照组。结果显示: 感染组各时间点DIF血浆蛋白结合率均高于对照组, 感染组与对照组DIF血浆蛋白结合率与总药物浓度呈对数关系: y=-9.01ln x+74.34和y=-4.81ln x+65.15, DIF血浆蛋白结合率与游离药物浓度的对数关系式分别为: y=-6.36ln x+64.91和y=-4.36ln x+ 60.63; 感染组和对照组血浆药时曲线均可使用开放性二室模型描述; 感染组DIF的吸收和消除慢于对照组, 其表观分布容积和曲线下面积大于对照组。结果显示异育银鲫体内感染嗜水气单胞菌促使DIF血浆蛋白结合率升高; 血浆蛋白结合率升高导致药物以结合药物的形式储存于血液中可能是导致药物组织分布受限、消除缓慢、长时间滞留于血液原因之一。     

温度、盐度和pH对小球藻生长率的联合效应

采用中心复合设计（CCD）研究了温度（1634℃）、盐度（1545）和pH（6.09.0）对小球藻（Chlorella sp. CHX-1）生长的联合效应。结果表明,温度、盐度与pH的一次、二次效应都对小球藻比生长速率有极显著影响（P0.01）;温度与盐度间、温度与pH间的互作效应对小球藻比生长速率影响显著（P0.05）,而盐度与pH间的互作效应影响不显著（P0.05）;三因子影响度大小依次为:温度pH盐度。采用响应曲面法建立了温度、盐度和pH对小球藻比生长速率影响的模型方程,该模型的决定系数0.9759,矫正决定系数0.9542,说明模型的拟合度极高;模型的预测决定系数0.8367,表明可用于预测小球藻比生长速率的变化。通过模型优化和验证试验,得出在温度、盐度和pH组合为26.7℃/25.5/7.3时,小球藻比生长速率达到最大值0.69,满意度为0.999。本试验结果可为小球藻生产提供理论指导。       

黄颡鱼重组生长激素的制备及对其鱼苗生长的影响

生长激素在渔业生产中具有重要的应用价值, 通过制备黄颡鱼(Pelteobagrus fulvidraco)同源重组生长激素并用于促生长实验, 从而为建立鱼苗快速培育方法提供理论依据。根据已知黄颡鱼生长激素(PfGH)基因cDNA序列, 利用IPTG诱导和SDS-PAGE分析方法, Western印迹表明在IPTG终浓度1.0 mmol/L、温度17℃和培养时间14h的条件下, 黄颡鱼生长激素基因在大肠杆菌中大量表达, 获得重组生长激素蛋白。然后, 随机选取黄颡鱼分为4组放入室内水族箱中进行养殖, 每箱35尾, 体质量为(0.850.01) g, 每组设3个平行, 水体循环净化。用制备的重组生长激素浓度分别为0、1、5和10 mg/L对黄颡鱼进行浸泡处理, 每周一次, 0为对照组。在养殖4周后, 对各组增重率和特定生长率进行比较, 结果表明1 mg/L组增重率和特定生长率分别比对照组提高了29.67% (P0.05)和11.90% (P0.05), 5 mg/L组增重率和特定生长率分别比对照组提高了21.32% (P0.05)和8.83% (P0.05), 各组间体成分等均无明显差异。停用生长激素4周后, 各组黄颡鱼的生长性能、体成分等均无显著差异。研究表明通过原核表达可以获得黄颡鱼重组生长激素, 用于促进鱼苗生长培育的最佳浸泡浓度为1 mg/L。       

Effects of food concentration on clearance rate and energy budget of the Arctic bivalve Hiatella arctica (L) at subzero temperature

The influence of food concentration on clearance rate, respiration, assimilation, and excretion at −1.3 °C was studied on individuals of the bivalve Hiatella arctica (L.) from Young Sound, NE Greenland. Clearance rate, assimilation efficiency, respiration, and excretion rates were determined over a range of food concentrations using the microalga Rhodomonas baltica as food source. Physiological rates were generally low but responded significantly to increased food levels. Clearance rates and assimilation efficiency were reduced at increased food levels, whereas respiration and excretion increased. Assimilation efficiency was generally high, which may be an adaptation to the low food concentration during most of the year in NE Greenland. Low filtration rates limited ingestion rates and resulted in a low maximum assimilation of 3 J h⁻¹. Despite the low food intake, very low food concentrations were required for individual specimens to obtain a positive energy budget. Predicted growth based on rates of assimilation and respiration were compared to published estimates of annual growth in Young Sound. We estimate that 3 weeks of growth in the laboratory under optimal food conditions could match annual growth in situ. We interpret this as evidence that food limitation is the primary impediment to growth in this Arctic population.     

黄连须和小檗碱对草鱼非特异性免疫系统的影响及对嗜水气单胞菌感染的抵抗作用

为了评估黄连须(FRC)和小檗碱(BBR)对草鱼(Ctenopharyngodon idella)的非特异性免疫及对抵抗嗜水气单胞菌感染的影响, 鱼喂食含1.00%、0.50%、0.25%, 0.10%, 0.00%的FRC和0.05%BBR的饲料28d。喂养28d后, 鱼注射嗜水气单胞菌, 记录感染14d后的存活率。检测NBT活性、血清溶菌酶活性、吞噬活性和补体C3水平来评价药物对草鱼的免疫反应。结果表明, 与模型组相比, 喂养饲料含有FRC和BBR的各组提高NBT活性、血清溶菌酶活性、吞噬活性和草鱼补体C3水平。喂食0.50%FRC组感染细菌后的存活率最高, 与模型组比较增加44%。FRC和BBR的体外抗菌活性采用最小抑菌浓度的方法进行了研究, 并显示出较强的抑制作用。结果表明, FRC和BBR可以用作免疫刺激剂以提高草鱼非特异性免疫和对嗜水气单胞菌引起疾病的抵抗。       

兰州鲇与鲇、黄河鲤肌肉品质比较研究

为深入探究兰州鲇(Silurus lanzhouensis)肌肉品质特性, 对黄河中兰州鲇、鲇(Silurus asotus)和黄河鲤(Cyrinus carpio)肌肉品质指标进行了测定。结果表明: 兰州鲇肌肉的pH、滴水损失、熟肉率、胶原蛋白、肌原纤维耐折力、黏附性、内聚性、胶黏性、咀嚼性、弹性和回复性等指标与鲇差异不显著(P>0.05), 失水率、肌纤维直径和硬度在二者间差异显著(P<0.05); 兰州鲇肌肉的pH、肌纤维直径、硬度、黏附性、回复性、胶黏性和咀嚼性与黄河鲤差异不显著(P>0.05), 肌肉滴水损失、熟肉率、失水率、胶原蛋白、肌原纤维耐折力、内聚性和弹性在二者间差异显著(P<0.05)。相关性分析表明, 兰州鲇肌肉咀嚼性与硬度呈极正相关, 其关系式为: y=0.3651x+25.339(R=0.97); 回复性与内聚性呈极正相关, 其关系式为: y=0.6279x-0.0929(R=0.91); 胶黏性与硬度呈极正相关, 其关系式为: y=2.4104x-41.155(R=0.97)。对兰州鲇7个质构指标进行了主成分分析, 提取出3个主成分, 累计方差贡献率为96.08%, 其中硬度是影响兰州鲇质构特性的主要因素。黄河中兰州鲇和鲇作为鲇属鱼类中形态十分相似的两个物种, 在肌肉品质特性上既有很大的相似性, 又有一定的不同, 这可能与这两种鱼种质特性的异同有关。     

兰州鲇线粒体Cytb基因的克隆与序列分析

为克隆兰州鲇（Silurus lanzhouensis）线粒体Cytb基因全序列,根据欧洲鲇（Silurus glanis）线粒体基因全序列设计特异引物进行兰州鲇线粒体Cytb基因的PCR扩增,得到1138 bp兰州鲇线粒体Cytb基因序列。对兰州鲇和其他13种鱼的线粒体Cytb基因核苷酸和氨基酸序列之间进行同源性比较,结果显示具有较高的同源性,核苷酸同源性介于61.38%-91.12%,氨基酸同源性介于76.62%-95.52%。对兰州鲇、欧洲鲇、大口鲇（Silurus meridionalis）、鲇（Silurus asotus）、越南鲇（Silurus cochinchinensis）的Cytb基因之间进行碱基替代分析,结果显示兰州鲇Cytb基因与鲇之间替换率最低,值为8.87%,转换/颠换值为3.21;与越南鲇之间替换率最高,值为14.41%,转换/颠换值为1.83。对本文克隆的兰州鲇Cytb基因与王庆容等测定的兰州鲇线粒体Cytb序列进行序列差异分析,结果显示两者之间替换率为11.16%,存在127个变异位点,转换/颠换比为4.08,遗传距离为0.1230。由NJ法基于兰州鲇和其他13种鱼的Cytb基因序列构建的系统进化树,结果显示与传统的分类地位基本吻合。       

贝氏高原鳅脑组织学观察

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Similar relative mutation rates in the three genetic compartments of Mesostigma and Chlamydomonas

Levels of nucleotide substitution at silent sites in organelle versus nuclear DNAs have been used to estimate relative mutation rates among these compartments and explain lineage-specific features of genome evolution. Synonymous substitution divergence values in animals suggest that the rate of mutation in the mitochondrial DNA is 10-50 times higher than that of the nuclear DNA, whereas overall data for most seed plants support relative mutation rates in mitochondrial, plastid, and nuclear DNAs of 1:3:10. Little is known about relative mutation rates in green algae, as substitution rate data is limited to only the mitochondrial and nuclear genomes of the chlorophyte Chlamydomonas. Here, we measure silent-site substitution rates in the plastid DNA of Chlamydomonas and the three genetic compartments of the streptophyte green alga Mesostigma. In contrast to the situation in animals and land plants, our results support similar relative mutation rates among the three genetic compartments of both Chlamydomonas and Mesostigma. These data are discussed in relation to published intra-species genetic diversity data for the three genetic compartments of Chlamydomonas and are ultimately used to address contemporary hypotheses on the organelle genome evolution. To guide future work, we describe evolutionary divergence data of all publically available Mesostigma viride strains and identify, for the first time, three distinct lineages of Mesostigma.     

异味物质β-环柠檬醛降解菌的分离和鉴定

β-环柠檬醛(β-cyclocitral)是由微囊藻产生的主要藻源性异味污染物之一。利用稀释涂平板法,从采集到的微囊藻水华水样中分离得到两株降解β-环柠檬醛的菌株DH16和DH18,16S rRNA序列比对和系统进化树分析表明它们分别属于食酸菌属(Acidovorax)和不动杆菌属(Acinetobacter)。实验室保藏的微囊藻毒素降解菌Novosphingobium sp.THN1对β-环柠檬醛也有降解效果,该菌属于新鞘氨醇杆菌属(Novosphingobium)。对三株菌进行以β-环柠檬醛为唯一碳源的培养实验,气相色谱检测分析表明DH18和THN1两株菌具有高效降解β-环柠檬醛的能力,可以作为研究β-环柠檬醛生物降解机理的理想材料。