印度胶树茎、叶制片新尝试

对于印度胶榕这种特殊类的材料制片,在取材、抽气和染色等过程中,常出现抽气不净和染色不均匀及乳汁脱不掉等问题,影响观察效果。从操作程序上进行了改进,取得了明显的效果,对于特殊植物材料制片有一定的参考价值。     

高寒草甸植被退化过程中生物土壤结皮演变特征

对生物土壤结皮(BSCs)在青藏高原的分布和作用还知之甚少,为了解其在高寒草甸退化过程中的演变特征,以高寒草甸为对象,研究其退化和人工重建对BSCs生长和分布影响。结果表明:随草甸退化,植被盖度不断降低,苔藓类结皮在禾草嵩草草甸和6年人工草地出现频度最高,随植被退化出现频度降低,"黑土滩"阶段最低(43.6%);黑斑、菌斑和地衣都是在矮嵩草阶段形成,在小嵩草草甸裂缝期或者剥蚀期出现频度最高,在禾草嵩草群落、6年人工草地及黑土滩均未出现;相关分析表明,苔藓类结皮出现频率与植被盖度呈极显著相关(P0.01),而与黑斑和地衣出现频率呈负相关,菌斑与地衣出现频度呈显著相关(P0.05)。BSCs在高寒草甸广泛分布,不同演替阶段,其分布和物种组成存在较大差别。植被生长和表土稳定性状况导致了BSCs的异质性分布格局。     

刺激隐神经C类纤维诱发体感皮层电反应(平均诱发电位)

当猫的隐神经A类纤维单独兴奋时,可引起同侧脊髓背表面电位 A-SSP(潜伏期 2.6±0.4ms)和对侧体感皮层诱发电位 A-CEP。A-CEP由早成分(潜伏期 9.6±1 1ms)和晚成分(203.0±10.gms)组成。当 C类纤维选择性传入时,出现特异的 C-CEP(潜伏期 134.4±25.9ms)和C-SSP(115.8±15.6ms)。C-CEP的幅值较A-CEP 小,并随C类纤维传入的数量而改变。C-CEP的最大幅值位于后乙状回一定部位,多为负或正-负电位,在皮层深层其相位倒转。与A-CEP相比,C-CEP的中枢延搁时间较长,跟随频率较低,对镇痛药较敏感。表明C-CEP不同于A-CEP,它是由C类传入所引起的,是在体感皮层内产生的。当A类和C类纤维同时传入时,只有A-CEP和A-SSP出现,而不出现C-CEP和C-SSP。在阻断电流逐渐增强过程中,C-CEP较C-SSP后出现;而在撤销阻断过程中,则C-CEP较C-SSP先消失。提示C类传入在中枢可能被A类传入所抑制,这种抑制可以发生在脊髓和脊上水平,后者可能更强。     

多色荧光原位杂交检测小鼠精子非整倍体

比多色荧光原位杂交技术评价了２－（４－噻唑）苯丙咪唑（ＴＢ）在雄性小鼠生殖形成过程中的非整倍体诱发效应。根据小鼠精子发育周期,以口饲法处理动物１１天,间隔２２天后取小鼠精子涂片,聚合应用８号,Ｘ及Ｙ染色体特异性ＤＮＡ探针进行多色ＦＩＳＨ,检测精子中出现的二倍体、双体、和缺本频率。结果发现：在２００ｍｇ／ｋｇ剂量组,上述３类异常精子频率均显著高于溶剂对照,其他２个剂量组的非整倍体精子频率与对照无显著     

基因频率的计算问题例析

基因频率是指某群体中,某一等位基因在该位点上可能出现的基因总数中所占的比率。关于基因频率的计算问题是常见的一类题型,大体可以分为两类:常染色体上的基因频率计算和X染色体上的基因频率计算。由于X染色体上的基因在Y上没有等位基因,是成单存在的,因此其计算方法与常染色体基因不同,需要特别注意。     

几类异质小麦雄性不育系育性恢复性的细胞遗传学研究

系统调查了4类异质(粘果、易变、偏凸、二角山羊草细胞质)1BL/lRS、非1BL/1RS小麦雄性不育系与其恢复系杂种F减数分裂中期Ⅰ出现单价体细胞频率,以及后期Ⅰ出现落后染色体和染色体桥细胞频率,并对中、后期染色体变异率与杂种F自交结实率进行了相关分析.结果表明(1)1BL/1RS型杂种在中期Ⅰ、后期Ⅰ染色体变异率要明显高于非1BL/1RS杂种;(2)4类异源细胞质在非1BL/1RS杂种中有着明显提高单价体细胞频率的作用;(3)在1BL/1RS杂种中,1B@1BL/1RS杂合核型染色体联会松弛,对单价体频率的影响远大于异源细胞质的影响;(4)1BL/1RS型杂种自交结实率与中期出现单价体细胞频率不直接相关,而与后期出现落后染色体和染色体桥细胞的频率呈高度负相关;(5)非1BL/1RS型杂种在减数分裂中、后期染色体行为相对稳定,易恢复且恢复度高,很有实际利用价值.     

遗传改良"新吉富" (NEW GIFT)尼罗罗非鱼RAPD-SCAR标记开发及其在品系鉴别中的应用

“新吉富”(NEW GIFT)尼罗罗非鱼是以1994年引进的 “吉富”(GIFT)品系尼罗罗非鱼为基础群体,经过14年9代系统选育后获得的新品种,该品种已被国家审定为良种,已在全国推广,迫切需要有效的分子遗传标记来鉴别该新品种并实施科学管理。该研究对良种群体开展了RAPD分析,并进一步将特异性的RAPD标记转化成了稳定的SCAR标记。 通过对“新吉富”群体的RAPD分析,找到了两个品种特异性的RAPD条带（S₃₀₄^{624 bp}和S₃₆^{568 bp}）。对品种特异性的RAPD条带进行了胶回收、克隆和序列测定。根据测序结果设计了两对位点特异性引物来扩增这两个品种特异性条带（简称SCAR标记Ⅰ和Ⅱ）,检测这两个SCAR标记在“新吉富”、“吉富”以及国内外7个养殖品系中的出现频率。SCAR标记Ⅰ（553 bp）在“新吉富”群体中的出现频率为85.7%,而在其基础群体（“吉富”）中的出现频率仅为16.7%;SCAR标记Ⅱ（558 bp）在“新吉富”群体中的出现频率达到91.4%,但在其它7个养殖品系中的出现频率仅在0%～70%之间。为验证这两个标记的可靠性,检测了这两个标记在一个埃及罗非鱼野生群体中的出现频率,发现SCAR标记Ⅰ和SCAR标记Ⅱ的出现频率分别为10%和70%,远低于在“新吉富”群体中的出现频率。这两个SCAR标记在“新吉富”良种群体中的高出现频率,预示它们可能与生长性能相关QTL位点间存在连锁关系,显示SCAR标记技术对选育世代间的纵向追溯、以及选育良种群体与其它养殖品系间的横向鉴别有较好应用前景。     

一种构建高质量随机肽库的有效方法

为构建完全随机化的基因工程肽库 ,克服现有简并方案中终止密码子和序列组成偏歧的不足 ,提出了一种新的简并DNA文库合成方式。通过这种分组式合成方式构建的肽库可以避免终止密码子的出现和氨基酸组成偏歧的发生 ,还可以控制随机化过程中不同氨基酸的参入比例。以一个 13肽库的合成过程为例对分组式合成法进行了实验 ,测序结果和对 19种氨基酸出现频率的统计表明没有终止密码子和半胱氨酸密码子出现 ,各氨基酸的出现频率接近均值 ,表明这种分组 混合 分组 ,辅以简并合成的方法是行之有效的 ,能满足各类高容量基因工程随机肽库要求。     

人体抗血友病因子Ⅸ的分子克隆

因子Ⅸ的功能性缺陷能导致一种称为Chrstimas病或血友病B的出血失常症,这种因子Ⅸ是血液凝决中的凝集因子之一。血友病B和A(因子Ⅷ(C)缺陷)都是Ⅹ染色体连锁的,在男性中大约以一万分之一的频率而出现。血友病B中,因子Ⅸ的功能性改变的分子基础尚不太清楚。     

群体有效含量和留种方式对家畜保种的影响

如果一个群体的大小有限,即使是没有突变、选择和迁移的影响,群体的基因频率也会产生一种特殊的变化。一个含有N个个体的小群体,可以认为是由前一代的种群随机地抽取2N个配子的结果。它的基因频率将按照二项展开式的概率变化,即按[p(A)+q(a)]~(2N)的方式展开。在这种随机变化的条件下,基因频率抽样误差的方差为q(1-q)/2N。这项抽样误差的     

贵州罗甸纳水上石炭统(宾夕法尼亚亚系)地层的再研究

本文详细描述了贵州罗甸纳水上石炭统(宾夕法尼亚亚系)剖面的生物地层和年代地层,其牙形刺序列自上而下可详细划分为：Streptognathodus isolatus, S. wabaunsensis, S. tenuialveus, S. firmus, Idiognathodus nashuiensis , Streptognathodus simulator, S. guizhouensis , S. gracilis-S, excelsus , S. cancellosus , S. clavatulus , S. nodocarinatus , Idiognathodus podolskensis , Mesogondolella clarki -Idiognathodus robustus , Diplognathodus ophanus-D, ellesmerensis, Idiognathoides ouachitensis, Streptognathodus expansus, Idiognathoides sulcatus parva, Idiognathodus primulus-Neognathodus bassleri, Idiognathodus primulus-Neognathodus symmetricus, Neognathodus symmetricus, Idiognathoides corrugatus-I, pacificus, I. sinuatus, I. sulcatus sulcatus, Declinognathodus noduli ferus 和 Gnathodus bilineatus bollandensis 等带。 Declinognathodus noduliferus 和 Streptognathodus isolatus 的首次出现分别代表上石炭统(宾夕法尼亚亚系)和二叠系的开始。根据牙形刺和有孔虫的序列,罗甸纳水剖面的上石炭统(宾夕法尼亚亚系)地层自下而上可划分为罗苏阶(Luosuan)、滑石板阶(Huashibanian)、达拉阶(Dalaan)和马平阶(Mapingian),并可与俄罗斯的巴什基尔阶(Bashkirian)、莫斯科阶(Moscovian)、卡西莫夫阶(Kasimovian)和格舍尔阶(Gzhelian),北美的莫罗阶(Morrowan)、阿托克阶(Atokan)、得梅因阶(Desmoinesian)、密苏里阶(Missourian)和弗吉尔阶(Virgilian)进行对比。另外,本文也详细讨论了剖面中的石炭系中间界线及石炭-二叠系界线。     

Taxonomic notes on water bloom forming Microcystis species (Cyanophyta) from China—An example from samples of the Dianchi Lake

Ten common species of Microcystis, based on the examination of water samples from the Dianchi Lake, Yunnan, China, were morphologically described, and their taxonomy was also discussed. They are Microcystis aeruginosa, M. botrys, M. firma, M. flos-aquae, M. ichthyoblabe, M. novacekii, M. pseudofilamentosa, M. smithii, M. viridis and M. wesenbergii. Taxonomic status of other Microcystis species reported in China was also evaluated. Key words Cyanophyta, Microcystis, morphology, taxonomy, China.     

中国靴耳属分类研究概况

对已报道的我国Crepidotus属种类进行了全面汇总,并概述了其分类研究现状。文献调查结果表明:国内已报道的该属种类名称共31个,包括30个种和1个变种,分布于全国26个省区。已报道的全部记录中,28个分类单元引证了标本,其余3个记录缺乏标本引证;7个记录的描述与国外权威描述存在差异,另有4个记录的报道未提供形态描述。淡紫靴耳不是Crepidotus属的成员,已被组合到其他属中。笔者接受"靴耳属"为Crepidotus属的汉语学名,并以此为属主名对属下的分类单元进行了全面修订。     

Notulae de Ranunculaceis sinensibus (ⅩⅩⅢ)

(1) In this paper, differences among the five genera constituting the tribe Cimi cifugeae of the family Ranunculaceae are discussed. Beesia, the first genus, with compound cymes and flowers bearing neither petals nor staminodes, is different from the other four genera with simple or compound racemes and flowers bearing either petals or staminodes, and may occupy a primitive position within the tribe. As to the other four genera, Souliea is characterized by the stem without basal leaf but with 2～5 sheath-like cataphylls, the sepals being deciduous but not caducous, moderate in size and petaloid, the petals being much smaller than sepals, but pink in color and more or less petaloid, the pollen grains being pan tocolpate or pantoporate, the carpels being 1～3 per flower, when mature forming dry linear follicles conspicuously reticulate on the surface and dehiscent along the ventral suture, and the seeds being reticulate-foveolate on the surface. These diagnostic characters indicate clear ly that Souliea might have deviated from the lineage formed by the next three genera, i. e. Anemopsis, Cimicifuga, and Actaea, which have their own well-recognizable diagnostic characters. Anemopsis is characterized by the normally developed basal leaf, the racemose inflorescence with sparse and few long pedicellate flowers, the sepals 7～10 in number, mod erate in size, and petaloid, the petals slightly smaller than sepals, the tricolpate pollen grains, the carpels 2～4 per flower, stalked, when mature forming dry oblong follicles with transverse veins on the surface, and the seeds with scaly membranous wings. Cimicifuga is distinguished by the normally developed basal leaf, the caducous, small, often sepaloid sepa ls, the organs of the second floral whorl sometimes with empty sterile anthers being stamin odes not petals, the tricolpate pollen grains, the carpels 1～8 per flower, when mature form ing dry oblong or ovoid follicles with transverse veins on the surface, and the seeds usually with scaly membranous wings. The last genus Actaea is different by the basal leaf trans formed into a small scale, the caducous, small, often sepaloid sepals, the organs of the sec ond floral whorl being clawed petals, the pollen grains with 3(4～6) colpi, carpel 1 per flow er, when mature forming a fleshy indehiscent berry smooth on the surface and without any veins, the seeds roughish or slightly rugose, neither foveolate nor winged on the surface, and the advanced most asymmetric karyotype. According to the diagnostic characters given above, we believe that Beesia, Souliea, Anemopsis, Cimicifuga, and Actaea do represent five independent genera, and the treatment of the tribe Cimicifugeae including these five genera in it by Hutchinson (1923), Janchen (1949) and some other authors, has precisely shown the taxonomic diversity within the tribe. We are therefore unable to accept the treatment published by Compton et al. (1998) to lump the two genera, Souliea and Cimicifuga, into the genus Actaea. (2) Compton et al. (1998, 1997) found out that the Chinese plants previously identified by various authors as Cimicifuga foetida L., in which the terminal and lateral racemes of the compound raceme flower more or less simultaneously, differ from the true C. foetida L. in northern Asia, in which the terminal raceme of the compound raceme flowers before the lateral ones, and thus restored the species name Cimicifuga mairei Lévl. , which was formerly reduced to the synonymy of C. foetida L. , for the Chinese plants. After examining the specimens collected from Siberia and from Southwest China we failed to find out any other differences in both vegetative and reproductive organs between the plants of the two regions, and we consider that it is better to treat the populations in Southwest and Central China as a geographical variety of Cimicifuga foetida L. A new combination, Cimicifuga foetida L. var. mairei (Lévl.) W. T. Wang & Zh. Wang, is thus made. (3) 3 species of Delphinium, 1 species and 1 variety of Clematis are described as new.     

下毛目纤毛虫的系统修订Ⅱ. 尾柱亚目(纤毛动物门)

对尾柱亚目 Urostylina Jankowski, 1979 中的各科、属进行了重新修订.该亚目的特征为:腹面具典型的中腹棘毛或在个体发生时出现中腹棘毛.修订后的尾柱亚目共4科19属:尾柱虫科 Urostylidae 左、右缘棘毛多列或至少有一侧缘棘毛为多列;全列虫科 Holostichidae 左、右缘棘毛各一列,具典型中腹棘列毛或复合中腹棘毛列;伪小双虫科 Pseudoamphisiellidae 仅具两列发生学意义上的中腹棘毛列,两者相互间宽位分离;帕森虫科 Patteroniellidae 中腹棘毛列不甚明确,数目少,且近于散布.此外, 给出了各科及属的检索表, 并附各属纤毛图式, 对部分属进行了讨论.     

Solid-phase Chemistry: A Useful Tool to Discover Modulators of Protein Interactions

The Solid phase synthesis (SPS) concept, first developed for biopolymers, has spread in every field where organic synthesis is involved. While the potential of the solid-phase method was obvious in 1959 to its discoverer, Prof. R. B. Merrifield, it was unpredictable its dominance in peptide synthesis and especially in combinatorial chemistry, an area not yet conceived. SPS paved the way for solid-phase combinatorial approaches (extensively reviewed in (Choong, I. C. and Ellman, J. A.: 1996, Annu. Rep. Med. Chem. 31, 309–318; Obrecht, D. and Villalgordo, J. M.: 1998, Solid-supported Combinatorial and Parallel Synthesis of Small-Molecular-Weight Compound Libraries. Pergamon Press Ltd., Oxford, UK; Chabala, J. C.: 1995, Curr. Opin. Biotechnol. 6, 632–639; Kamal, A., Reddy, K. L., Devaiah, V., Shankaraiah, N., Reddy, D. R.: 2006, Mini Rev. Med. Chem. 6, 53–69; Whitehead, D. M., McKeown, S. C., Routledge, A.: 2005, Comb. Chem. HTS 8, 361–371; Nefzi, A., Ostresh, J. M., Houghten, R. A.: 1997, Chem. Rev. 97, 449–472; Gordon, E. M., Gallop, M. A., Patel, D. V.: 1996, Acc. Chem. Res. 29, 144–154)) as many laboratories and companies focused on the development of technologies and chemistry suitable to this new methodology. This resulted in the spectacular outburst of combinatorial chemistry, which profoundly changed the approach for new drug discovery. Combinatorial chemistry is currently considered a valid approach for a wide range of biomedical applications, such as, target validation and drug discovery.     

Importance of biological and abiotic factors for geochemical cycling in a freshwater eutrophic lake

Here we report the results of a comprehensive biogeochemical monitoring of Rostherne Mere in 1998, including changes in dissolved oxygen, organic carbon and nitrogen, nitrate/nitrite, ammonia, Al, Na, S, K, Mg, Ca, Si, Fe, Mn, orthophosphate, particulate N & P, suspended solids, temperature, pH, chlorophyll-a and zooplankton. The results demonstrated the major influence of primary producers on the overall geochemical cycling of N, P and Si, and suggested that the significance of zooplankton might have been previously underestimated. For major anions and cations, however, the influence of biota on lake water concentrations appeared to be negligible, reflecting the fact that these chemicals were present far in excess of plankton requirements. Thus changes in concentrations of Ca, K, Na, Mg and S were rather limited and must have reflected changes in hydrological and meteorological parameters. K, however, demonstrated a transitional pattern, reflecting some influence of biological uptake. During the stratification period, the slow processes of bacterial decomposition in the hypolimnion gradually released chemicals contained in the materials accumulated in the bottom layer, remarkably increasing the concentrations of dissolved compounds of those elements present in amounts comparable with the pool stored in the sedimenting detritus (e.g. orthophosphate P, ammonia N, Si and DOC). The decomposition also resulted in a drop in the redox potential, followed by partial denitrification and chemical release from the sediments. The hypolimnion of the Mere was confirmed to remain at the stage of Mn release, characterised by accumulation of DOC, orthophosphates, ammonia and initial stages of denitrification. High levels of P released from the sediments during the stratification period suggest that the lake’s recovery after sewage diversion might be further delayed.     

西藏合腹茧蜂属一新种记述（膜翅目：茧蜂科：甲腹茧蜂亚科）

合腹茧蜂属Phanerotomella Szepligeti中国已知7种,本文报道1新种,西藏合腹茧蜂P.xizangensis,sp.nov.,并附中国已知种检索表,模式标本保存于浙江大学应用昆虫研究所。     

Seed-coat anatomy in Fumariaceae-Fumarioideae

Seed-coat anatomy is described in 122 species of Fumarioideae, which represent all the genera, subgenera, and most sections. Nine seed-coat types were recognized: (I) Dicentra subg. Hedycapnos , (II) Dicentra subg. Chrysocapnos , (III) Dicentra subg. Macranthos , (IV) Dicentra subg. Dicentra , (V) Corydalis p.p. , (VI) rest of Corydaleae, Cysticapnos, Pseudofumaria and Ceratocapnos , (VII) Discocapnos and Sarcocapnos p. p. , (VIII) Sarcocapnos p. p., Platycapnos and Trigonocapnos , and (IX) Fumariinae. Variable characters are polarized based on the comparison with Fumariaceae Hypecooideae, Papaveraceae and Pteridophyllaceae. It is assumed that endotestal seed-coat type (I) is most primitive, that exotestal seed coat types (II—VIII) are derived therefrom, and that the reduction of the mechanical layer, including the origin of thin seed-coat type (IX) occurred repeatedly in combination with indehiscent, hard-walled fruits. Dicentra subg. Hedycapnos (with type I) possesses a combination of primitive testal characters unique within the subfamily, suggesting it represents a sister group to the rest of the subfamily. Each of the other subgenera (with II, III or IV) is also characterized by a unique combination of seed-coat characters, which are found in the outgroups but not in the other genera. Seed-coat characters support the monophyly of Fumarioideae exclusive of Dicentra subg. Hedycapnos , Fumarioideae exclusive of Dicentra , of Dicentra subg. Dicentra , of Corydalis p.p. , and of Fumariinae.