五种齿突蟾在横断山南潜在地理分布预测

由于栖息地质量下降,近年来齿突蟾属物种种群数量急剧减少,明确齿突蟾属物种空间分布,是监测、管理、保护齿突蟾属物种的基础。横断山区可能是齿突蟾属的起源中心和分化中心,但齿突蟾属在横断山区的地理分布格局尚不明确。利用优化后Maxent模型,首次预测西藏齿突蟾Scutiger boulengeri、刺胸齿突蟾Scutiger mammatus、胸腺齿突蟾Scutiger glandulatus、圆疣齿突蟾Scutiger tuberculatus、贡山齿突蟾Scutiger gongshanensis 5种高海拔齿突蟾属物种在横断山南生物多样性保护优先区域的潜在地理分布,并分析其与环境因子的关系。结果显示,5种齿突蟾属物种在横断山南的潜在地理分布格局存在差异,西藏齿突蟾主要分布在横断山南的北部,圆疣齿突蟾主要分布在横断山南东北部的四川省境内,贡山齿突蟾主要分布在横断山南的西南部,刺胸齿突蟾和胸腺齿突蟾的潜在分布格局较为相似,在横断山南的中部、西北部地区都有较多分布,但胸腺齿突蟾潜在分布区更为碎片化。另外,横断山南北部地区的齿突蟾属丰富度明显高于南部地区。环境变量贡献率和刀切法结果显示温度因子和降水因子是决定横断山南齿突蟾属潜在分布的主要因素,最冷季降水量对西藏齿突蟾、贡山齿突蟾、圆疣齿突蟾潜在分布有重要影响,但它们对最冷季降水量的偏好存在差异。此外,研究也显示,通过评估潜在的Maxent参数组合,选择最佳的Maxent模型是有效且必要的。     

亚洲高海拔锄足蟾的属间亲缘关系、分化及其与青藏高原形成的关系

本文在研究高海拔锄足蟾的属间分类及分布规律的基础上,对所属的齿蟾属Oreolalax、齿突蟾属Scutiger的齿突蟾亚属Scutiger,(Scutiger)和猫眼蟾亚属Scutiger(Aelurophryne)的成体外形和骨骼、蝌蚪的形态以及核型等24个性状进行综合分析,同时探讨了属间亲缘关系。结果表明:齿蟾属较原始,齿突蟾属较特化,它们可能起源于共同的祖先——原始齿蟾。在齿突蟾属中猫眼蟾亚属比齿突蟾亚属更为特化,后者与齿蟾属的亲缘关系相对较近。它们的分化与青藏高原的抬开有密切关系。     

亚洲高海拔锄足蟾的地理分布特点,起源与演化,分化中心的探讨

本文在探讨亚洲高海拔锄足蟾的属间分类的基础上,进一步对其齿蟾属Oreolalax和齿突蟾属Scutiger所隶的齿突蟾亚属Scutiger(Scutiger)、猫眼蟾亚属Scutiger(Aelurophryne),共计29种的地理分布及其特点作了概括性的综述;并探讨了他们的起源和演化途径;横断山系地区可能是它们的主要分化中心和物种形成中心。     

我国齿突蟾属(两栖纲：无尾目)资源现状及保护对策

齿突蟾属物种已知19种左右,中国分布有16种。该属大多数物种为珍贵、稀有濒危物种。主要生活在高寒山区及高原地区,卵产于高寒缓流的山溪中。本文梳理了分布于我国齿突蟾物种的资源现状,分析了导致其种群下降的原因。并在此基础上提出了相应的保护对策,以期能对该属物种保护和资源利用起到参考作用。     

四川省康定市两栖动物多样性及其时空分布格局

为了全面掌握四川省康定市两栖动物多样性现状及其时空分布格局, 本研究系统选取61个10 km × 10 km调查网格, 每个网格设置至少3条样线, 分别于2016年9月、2017年5月和7月进行实地调查。所有调查网格中, 有11个网格未调查到两栖动物, 有1个网格调查到的两栖动物物种数最多达到了10种。调查共发现两栖类动物2,639只, 隶属于2目5科7属14种, 其中优势度最高的是中华蟾蜍(Bufo gargarizans), 其次是倭蛙(Nanorana pleskei)和高原林蛙(Rana kukunoris), 优势度最低的是九龙齿突蟾(Scutiger jiulongensis)。不同月份两栖动物物种数和个体数调查结果显示: 5月份调查到的个体数最多, 共发现966只; 9月份调查到的物种数最多, 有13种。不同月份间两栖动物的物种相对多度结果显示: 5月和7月调查到的优势物种均为中华蟾蜍, 9月份为倭蛙。大部分两栖动物分布在海拔3,000-4,000 m之间; 四川湍蛙(Amolops mantzorum)和中华蟾蜍的海拔分布跨度较大, 分布范围在海拔1,300-3,600 m之间; 刺胸齿突蟾(Scutiger mammatus)和九龙齿突蟾等物种海拔分布范围较窄, 刺胸齿突蟾分布在海拔3,200-3,300 m之间; 九龙齿突蟾仅在海拔3,600 m左右。比较影响物种丰富度分布格局的5项环境因子发现, 年均降水量和植被类型数与物种丰富度显著相关, 其次是平均海拔, 而年均温和植被覆盖指数相关性相对较弱。本研究摸清了康定市两栖动物的多样性及其分布格局, 为康定市生物多样性保护提供基础数据。     

齿突蟾属四个物种皮肤的组织学观察

观察了齿突蟾属Scutiger 2亚属、4物种[西藏齿突蟾S.(Scutiger) boulengeri、刺胸猫眼蟾S.(Aelurophryne) mammatus、木里猫眼蟾S.(A.) muliensis和胸腺猫眼蟾S.(A.) glandulatus]的体背、体腹皮肤及其腺体的组织形态学结构,结果表明:4个物种...     

中国五种高山锄足蟾的核型、Ag-NORs和C-带的研究

作者用核型、Ag-NORs和C-带,对分布于川、滇两省的二属(齿突蟾、齿蟾)五种(胸腺齿突蟾、圆疣齿突蟾、凉北齿蟾、秉志齿蟾、疣刺齿蟾)锄足蟾作了属间和种间关系的比较分析,并讨论了它们的核型演化机制。结果表明:(1)齿突蟾和齿蟾两属间在核型和带型上都有明显的差异,演化途径主要的可能是含有重复DNA染色体片段的相互易位或臂间倒位;(2)属内不同种之间带型无显著差异,但某些对应染色体对间,其相对长度和臂比值差异明显,十分可能是常染色质片段的易位和臂间倒位所致;(3)凉北齿蟾有染色体数目变异多态现象;(4)五种锄足蟾均未发现异形性染色体。     

亚洲高海拔锄足蟾属间分类研究(Amphibia:Pelobatidae)

本文比较研究了高海拔锄足蟾类29种成体和蝌蚪的外形,25种的骨骼,8种的核型和带型,9种的眼晶体薄层凝胶等电聚焦电泳图谱等性状,并结合地理分布、生态环境及习性等因素综合而较全面地对中国锄足蟾科Pelobatidae的齿突蟾属Scutiger,猫眼蟾属Aelurophryne和齿蟾属Oreo-lalax三个类群的属间分类问题进行了探讨。研究表明:齿蟾属Oreolalax应为有效属,不宜作为齿突蟾属Scutiger的亚属;猫眼蟾属Aelurophryne与齿突蟾属Scutiger应同归一属,前者应为后者之亚属。     

四川省两栖类新记录——毕节掌突蟾

2020年4月在四川泸州画稿溪国家级自然保护区进行动物资源调查时,于水尾镇何家沟(105.583 382°E,28.288 271°N,海拔660 m)采到4号角蟾科Megophryidae掌突蟾属Leptobrachella物种标本(标本号:HGX2020022～HGX2020025),通过形态学比较、基于线粒体16S r DNA的贝叶斯法和最大似然法分子系统关系重建研究,确定4号标本为毕节掌突蟾Leptobrachella bijie,为四川省两栖类新记录。目前,我国有掌突蟾属物种共28种,其中20种为近10年内描述的新物种,四川仅分布有峨山掌突蟾L.oshanensis一种。此次在四川泸州发现毕节掌突蟾不仅为四川省两栖类增添了新成员,更表明掌突蟾属的物种多样性被低估,亟待深入研究。     

贵州高原6种掌突蟾形态特征差异分析

本文通过形态指标测量,比较了分布于贵州高原的6种掌突蟾属(Leptobrachella)物种的形态特征差异.结果 显示,头体长比较,6种掌突蟾的头体长从大到小依次为赤水掌突蟾(L.chishuiensis)、绥阳掌突蟾(L.suiyangensis)、金沙掌突蟾(L.jinshaensis)、毕节掌突蟾(L.bijie...     

六种藓类植物茎的比较解剖学研究

通过对6种藓类植物,即褶叶青藓(Brachythecium salebrosum(Web.et Mohr.)B.S.G.)、湿地匐灯藓(Plagiomnium acutum(Lindb.)Kop.)、侧枝匐灯藓(Plagiomnium maximoviczii(Lindb.)Kop.)、大凤尾藓(Fissidensnobilis Griff.)、大羽藓(Thuidium cymbifolium(Doz.et Molk.)B.S.G.)和大灰藓(Hypnum plumaeforme Wils.)嫩茎和老茎的石蜡切片和显微观察发现,同一藓类植株的嫩茎和老茎,茎结构稳定,不同种藓类植物茎横切面具有不同特征.植物体茎横切面形状、表层细胞的层数、细胞大小和细胞壁厚薄、皮层细胞大小和形状、中轴的有无以及比例等特征可以作为藓类植物的分科分类依据之一.     

Photoregulation of seed germination of wild-type and of an aurea-mutant of tomato

Seed germination of an aurea mutant of tomato ( Lycopersicon esculentum Mill.) is promoted by continuous irradiation with red, far-red or long-wavelength far-red (758 nm) light as well as by cyclic irradiations (5 min red or 5 min far-red/25 min darkness). Far-red light applied immediately after each red does not change the germination behaviour. Seed germination of the isogenic wild-type, cv. UC-105, is promoted by continuous and cyclic red light while it is inhibited by continuous and cyclic far-red light and by continious 758 nm irradiation. Far-red irradiation reverses almost completely the promoting effect of red light. The promoting effect (in the aurea mutant) and the inhibitory effect (in the wild-type) of continuous far-red light do not show photon fluence rate dependency above 20 nmol m⁻² s⁻¹. It is concluded that phytochrome controls tomato seed germination throgh low energy responses in both the wild type and the au mutant. The promoting effect of continuous and cyclic far-red light in the au mutant can be attributed to a greater sensitivity to P_fr.     

Interconnection of parameters of regulation system of lipid peroxidation and of morphophysiological parameters of mouse liver

A complex analysis of seasonal fluctuations of the mean group parameters of the system of regulation of lipid peroxidation has been performed in liver of Balb/c mice. Association of lipid characteristics and morphophysiological parameters is studied in the Balb/c mouse liver. An inter-connection is revealed between the liver index and the amount of lysoforms of phospholipids, the scale and character of the interconnection differing essentially depending on proportion of phos-phatidylcholine in mouse liver phospholipids.     

Cause of Senescence of Nine Sorts of Flowers

The levels of endogenous phytohormones and respiratory rate in nine sorts of flowers such as Cymbidium faberi Rolfe, Nopalxochia ackermannii Kunth and others were investigated both at full bloom and senescence and meanwhile the effect of exogenous phytohormones on prolonging the blossoms and promoting ethylene production were tested. There is a high content of endogenous ethylene in all the long-lived flowere, about 3–16 folds higer than the short-lived ones. There is a high level of ABA at full blooming flowers of short-lived flowers, in which there is no or only some cytokinins in it, but the ratio of CTK (6BA+zeatin)/ABA is smaller(l.7). The endogenous ABA reached a much higher level at senescence in all nine sorts of flowers, so it is reasonable to consider that it is ABA which plays an important role of regulation in controlling flower's senescence. There is a much higher level of GA3 and zeatin in the long-lived flowers which is not demonstrated in the shortlived ones. The respiratory rate is one of the factors controtling the longevity of flowers, but it does not play a decided role. Application of 6BA and zeatin prolongs distinctly orchid’s longevity, however exogenous IAA through the promotive action on ethylene production, evidently extends the longevity of the flowers of the Nopalxochia ackermannii Kunth.     

真菌类遗传学分析的知识结构教学

本文以认知结构理论为指导,讨论了真菌类遗传分析与高等动植物遗传分析的内在联系,认为利用这种内在联系进行教学可收到好的效果并说明了作者的具体教学过程。 Abstract:In the paper, the relationship between genetic analysis of Fungi and genetic analysis of high animal and plant was discussed.A good results were obtained when we adopted this method in the teaching.     

Physiological characteristics of various species of strains of carboxydobacteria

Seven strains of aerobic carbon monoxide-oxidizing bacteria (carboxydebacteria) when growing on CO as sole source of carbon and energy had doubling times which ranged from 12–42 h. The activity profiles obtained after discontinuous sucrose density gradient centrifugation indicated that the CO-oxidizing enzymes are soluble and the hydrogenases are membrane-bound in all strains examined. The CO-oxidizing enzymes of Pseudomonas carboxydohydrogena, Pseudomonas carboxydoflava, Comamonas compransoris, and the so far unidentified strains OM2, OM3, and OM4 had a molecular weight of 230,000; that of Achromobacter carboxydus amounted to 170,000. The molecular weights of the CO-oxidizing and H₂-oxidizing enzymes turned out to be identical. The cell sonicates were shown to catalyze the oxidation of both CO and H₂ with methylene blue, thionine, phenazine methosulfate, toluylene blue, dichlorophenolindophenol, cytochrome c or ferricyanide as electron acceptors. Methyl viologen, benzyl viologen, FAD⁺, FMN⁺, and NAD(P)⁺ were not reduced. The spectrum of electron acceptors was identical for all strains tested. Neither free formate, hydrogen nor oxygen gas were involved in the CO-oxidation reaction. Methylene blue was reduced by CO at a 1:1 molar ratio. The results indicate that CO-oxidation by carboxydobacteria is catalyzed by identical or similar enzymes and that the reaction obeys the equation CO+H₂OCO₂+2H⁺+2e^- as previously shown for Pseudomonas carboxydovorans.Dedicated to Otto Kandler remembering almost three decades of enjoyable cooperation     

Modulation of allostery of pyruvate kinase by shifting of an ensemble of microstates

Since the introduction of the concepts of allostery about four decades ago, much advancement has been made in elucidating the structure-function correlation in allostery. However, there are still a number of issues that remain unresolved. In this review we used mammalian pyruvate kinase (PK) as a model system to understand the role of protein dynamics in modulating cooperativity. PK has a triosephosphate isomerase (TIM)(α/β)₈ barrel structural motif. PK is an ideal system to address basic questions regarding regulatory mechanisms about this common (α/β)₈ structural motif. The simplest model accounting for all of the solution thermodynamic and kinetic data on ligand-enzyme interactions involves two conformational states, inactive E^T and active E^R. These conformational states are represented by domain movements. Further studies provide the first evidence for a differential effect of ligand binding on the dynamics of the structural elements, not major secondary structural changes. These data are consistent with our model that allosteric regulation of PK is the consequence of perturbation of the distribution of an ensemble of states in which the inactive E^T and active E^R represent the two extreme end states. Sequence differences and ligands can modulate the distribution of states leading to alterations of functions. The future work includes: defining the network of functionally connected residues; elucidating the chemical principles governing the sequence differences which affect functions; and probing the nature of mutations on the stability of the secondary structural elements, which in turn modulate allostery.     

（鱼句）亚科花（鱼骨）型鱼类骨骼系统的比较

对我国花型Hemibarbuspattern鱼类作了骨骼系统比较,结果表明,此类型鱼类脑颅较长,副蝶骨平直或稍弯曲,眶蝶骨腹纵嵴发达(铜鱼Coreius septentrionalis例外),下颞窝和咽突中等大,基枕骨后突发达;脑颅中的上筛骨的后突、侧筛骨的外筛突,蝶耳骨的外突、上耳骨的后突、围眶骨和后颞窝等均有明显的差异;咽颅中的舌颌骨、尾舌骨、鳃盖骨和下咽齿的列数等又有显著的区别;附肢骨骼中的腰带骨、脊椎骨中的复合神经骨和第4椎骨腹侧的悬器等也有不同之处。据此,这些差异和区别可作为属间或种间的分类依据。