997 resultados para 23-226


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抚仙金线鲃(Sinocyclocheilus tingi)是抚仙湖的特有种.2009年3-4月,有4次繁殖试验取得了成功.先后试验了40尾雌鱼和20尾雄鱼,成功催产19尾雌鱼和15尾雄鱼,分别占雌雄鱼的47.5%和75.0%.获得鱼卵25 547粒,并实施干法受精.有16810粒受精,平均受精率为65.8%.孵化出鱼苗约6040尾,平均孵化率为23.6%.经过20目的饲养,仔鱼存活3 056尾,存活率为50.6%.抚仙金线鲃较低的催产率,可能是生殖功能紊乱所致:但也不排除是人工营造的条件离其自然环境需求尚有距离.要使抚仙金线鲃成为鱼鱇<鱼良>白鱼(Anabarilius grahami)之后又一当地特色养殖鱼种,突破其人工繁殖瓶颈,培育高品质鱼苗是必由之路.突破其人工繁殖,还可为研究抚仙金线鲃的生活史和保护该物种免于灭绝奠定良好基础.

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Objectives of the workshop included: presentation of research to stakeholders; briefing of stakeholders on project objectives, contents and activities; to get stakeholder perceptions and suggestions.

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目的:研究异丙酚对大鼠海马CA1区自发性兴奋性突触后电流(sEPSC)的影响。方法:断头法分离Wistar大鼠(13~19 d)海马半脑,用切片机切出400μm厚度的海马脑片,全细胞膜片钳记录CA1区锥体神经元sEPSC。20张脑片分为两组:脂肪乳剂组(n=10)和异丙酚组(n=10)。两组细胞稳定10~15 min后,加入90μl脂肪乳剂或异丙酚(相当于100μmol/L),记录40 min sEPSC。膜钳制电压为-70 mV。结果:100μmol/L异丙酚降低sEPSC的频率达68.1%,降低sEPSC的幅值达29.1%,缩短sEPSC的半衰期达49.3%;另外,异丙酚缩短sEPSC的上升时间达29.1%,减少曲线下面积达74.7%。结论:异丙酚通过影响突触前膜递质释放和突触后膜受体功能两个因素抑制兴奋性突触活动

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在整理华缨鱼属标本时发现,1993年9月在广西壮族自治区天峨县红水河水系地下河采集到的一批 标本为一个未经发表的新种,新种订名为大眼华缨鱼(&加c瑚soc^eiz獬胧gnzDp^f^8h邯)。其下咽齿2行,可与 下咽齿3行的7种华缨鱼相区别,而与属内同样具2行下咽齿的贵州华缨鱼(s.肛妇b淝瑚括)、小口华缨鱼 (Js.m幻M幻,抛£琳)和宽唇华缨鱼(5.z06缸t琳)亲缘关系较近。但:(1)新种胸鳍中点上方无黑斑,背鳍分枝 鳍条7,腹鳍分枝鳍条7,背鳍前鳞15—16,眼大,头长为眼径2.5—3.1倍,眼径为头宽44.7%一57.8%,吻 须后伸至前后鼻孔之间或眼前缘,口角须后伸至眼前缘至眼中之问或眼中至眼后缘之间,体长为尾柄高8.9一 lO.7倍,头长为吻长2.5—3.7倍,可与贵州华缨鱼(胸鳍中点上方有一明显黑斑,背鳍分枝鳍条8,腹鳍分枝 鳍条8,背鳍前鳞12—14,头长为眼径4.O一5.0倍,眼径为头宽16.6%一20.7%,吻须后伸不达后鼻孔后缘, 口角须后伸至眼前缘,体长为尾柄高7.2—8.2倍,头长为吻长1.9—2.2倍)相区别;(2)新种背鳍前鳞15— 16,侧线鳞39~40,侧线上鳞4.5—5.5,背鳍分枝鳍条7,鳃耙13,腹鳍末端伸达肛门,眼径为头宽44.7%一 57.8%,可与宽唇华缨鱼(背鳍前鳞22,侧线鳞42—45,侧线上鳞6.5,背鳍分枝鳍条8,鳃耙10,腹鳍末端 不达肛门,眼径为头宽23.3%一30.O%)相区别;(3)新种与同水系的小口华缨鱼在鳍条数、侧线鳞、体色、 斑纹等方面最为相似,但新种围尾柄鳞14/16,眼大,头长为眼径2.5—3.1倍,腹鳍末端伸达肛门,口角须后 伸至眼前缘至眼中之间或眼中至眼后缘之间,吻皮边缘深裂成小穗,背鳍起点距吻端较距尾鳍基为近,背鳍长 大于头长,体长为尾柄长4.8—5.9倍,头长为吻长2.5—3.7倍,尾柄长为尾柄高1.6—2.1倍,可与之(围尾 柄鳞12,眼小,头为眼径4.4—4.6倍,腹鳍末端不达肛门,口角须伸达眼下方,吻皮边缘不开裂或开裂不明 显,背鳍起点距吻端等于距尾鳍基,背鳍条约等于头长,体长为尾柄长6.1—6.4倍,头长为吻长2,1—2.4倍, 尾柄长为尾柄高1.4—1.5倍)相区别。

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石林盲高原鳅T. Shilinensis Chen et Yang, sp. nov.是在我国发现的第 四种洞穴条鳅鱼 类。描述了其形态特征。在溶洞间的地理隔离作用下, 形成了 与环境相适应的各自形态特点, 最终分别演化成为目前的石林盲高原鳅和个旧盲 高原鳅。标本模式存作者单位。图2表1参6

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笼养大紫胸鹦鹉取食活动占观察时间的14.51%,是其主要行为活动之一。日取食活动呈现早(7:00#approx#10:00)、晚(15:00#approx#19:00)2个明显的高峰。每日取食(32.12+ -14.28)次,累计日取食时间(153.23+ -73.11)min。每次取食的时间平均为(5.29+ -1.06)min。两性和成幼间以及不同时期的取食活动有一定的差异。在整个取食过程中,除拾取(45.47%)和咀嚼(46.49%)两种取食行为外,还有身体护理(2.51%)、运动(3.59%)、静栖(1.72%)、攻击(0.12%)、求偶(0.1%)等活动出现。逐步回归分析表明:影响大紫胸鹦鹉成鸟取食活动的主要因素是生物学因素;5月龄以前幼鸟的取食行为除受生物学因素的影响外,还与温度有一定的关系。

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通过对采自云南程海和珠江、闽江、长江、辽河、松花江等水系蛇ju标本的形态、度量特征进行仔细分析和比较,认为蛇ju程海种群是蛇ju的1个新亚种,命名为程海蛇ju(Saurogobio dabryi chenghaiensis)。程海蛇ju的特征为:吻皮发达,盖过上唇;上下唇布满发达的乳突;体及尾柄极细长,体高为体长的12.7%-15.0%,尾柄高为体长的5.5%-6.1%、为尾柄长的31.8%-39.1%;沿体侧中轴自鳃孔上方至尾鳍基具一浅色暗纹,其上布有6-11个大型棒状黑斑(黑斑长为宽的2-4倍);肛门位于腹鳍长度的中点之后;尾鳍最长鳍条为其最短鳍条的2倍以上;仅分布于云南程海。

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作者在云南省盈江县采到鱼类标本44号,经鉴定为我国鱼类区系中科、属、种的首次记录--印度囊鳃鲇(Heteropneustes fossilis)。

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基于外部形态特征和内部骨骼特征对鲤科鲤属中鲤亚属进行了分支系统学分析。内群包括中鲤亚属的全部5种和鲤亚属的2种鱼类,外群采用乌原鲤。在鲤属鱼类和外群间共有48个性状存在变化。系统发育分析采用PAUP~(*)软件的Parsimony和Bootstrap两种方式的Branch-and-Bound算法。排除不能极化的特征和特有离征之后,还有28个特征可用,由这28个特征可得到唯一的系统树,树长69,一致性系数0.7246,排除无用特征的一致性系数0.6122,保留系数0.6346。由5种中鲤组成的中鲤亚属明显不构成一个单系群。结果表明:中鲤亚属是一个复系群,该类元应该被撤销。

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Fishes of the genus Barbodes in Yunnan have been reviewed and 2 new species are described on the basis of specimens deposited in Kunming institute of Zoology, Chinese Academy of Sciences. Counts and measurements follow Chu and Chen (1989). Barbodes heterostomus is distinguished by its terminal mouth, with gape being horizontal in the male, and acclivitous in the female, last unbranched dorsal ray smooth with upper 1/3 articulated; dorsal fin origin anterior to pelvic fin origin; no dark lateral band on sides of body; gill rakers 13-19; lateral line scales 24-29; longest caudal ray length about 2 times that of shortest. It is distributed in Longchuanjiang and Dayingjiang (upper Irrawaddy). Barbodes baoshanensis is distinguished by its smooth last unbranched dorsal ray with upper 1/3-1/2 articulated; dorsal fin origin anterior to pelvic fin origin; sides of body with a dark longitudinal band; gill rakers 13-14; lateral line scales 23-28. It occurs in Nujiang (upper Salween) and Longchuanjiang. A key to the species of Barbodes in Yunnan is provided.

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The loach genus Oreonectes is reviewed in this study. Six valid species are recognized, including two new species. Oreonectes polystigmus sp. nov., and Oreonectes microphthalmus sp. nov. are described from the Guangxi Zhuang Autonomous Region, China. Amon

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The identity of Schizothorax griseus Pellegrin, 1931, is clarified and the species redescribed. Three new species previously identified as S. griseus are described: S. nudiventris, from the Lancang Jiang, China; S. heterophysallidos, from the Nanpan Jiang

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A new species of the genus Glyptothorax, Glyptothorax obliquimaculatus sp. nov. is described from the Xiaohei River, a tributary of the Nanting River, Salween drainage, in southwestern Yunnan province, China. This new species can be distinguished from its congeners by the following combination of characteristics: unculiferous ridges of the thoracic adhesive apparatus extending anteriorly onto the gular region; body with irregular dark blotches scattered along lateral surface (blotches mostly oblique); skin smooth on head and body; dorsal spine smooth without serrations on its posterior margin; lips smooth; posterior margin of pectoral spine with 7-8 serrations; dorsal-fin base 11.0-13.2% SL; pectoral-fin length 15.6-19.6% SL; depth of caudal peduncle 8.6-9.8% SL; head width 19.1-24.0% SL; nasal barbel length 23.3-33.3% HL.

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核纤层是细胞核内极其重要的结构,近年来有关核纤蛋白及其基因的研究取得了较大进展,文中就国际上有关该领域研究的新进展并结合作者所在实验室近年来的有关研究结果,从核纤层蛋白成分及功能,核纤层蛋白基因及其起源分化等方面进行了较系统的介绍和探讨,并提出了一些值得深入研究的新问题。